Tesis: "Micro-embossing"

1

Firko, Megan (Megan Rose). "Hot micro-embossing of thermoplastic elastomers". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/54461.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, September 2008.
"June 2008." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 69-71).
Microfluidic devices have been a rapidly increasing area of study since the mid 1990s. Such devices are useful for a wide variety of biological applications and offer the possibility for large scale integration of fluidic chips, similar to that of electrical circuits. With this in mind, the future market for microfluidic devices will certainly thrive, and a means of mass production will be necessary. However PDMS, the current material used to fabricate the flexible active elements central to many microfluidic chips, imposes a limit to the production rate due to the curing process used to fabricate devices. Thermoplastic elastomers (TPEs) provide a potential alternative to PDMS. Soft and rubbery at room temperature, TPEs become molten when heated and can be processed using traditional thermoplastic fabrication techniques such as injection molding or casting. One promising fabrication technique for TPEs is hot micro-embossing (HME) in which a material is heated above its glass transition temperature and imprinted with a micromachined tool, replicating the negative of the tools features. Thus far, little research has been conducted on the topic of hot embossing TPEs, and investigations seeking to determine ideal processing conditions are non-existent. This investigation concerns the selection of a promising TPE for fabrication of flexible active elements, and the characterization of the processing window for hot embossing this TPE using a tool designed to form long winding channels, with feature heights of 66Cpm and widths of 80jpm. Ideal processing conditions for the tool were found to be pressures in the range of 1MPa-1.5MPa and temperatures above 1400.
(cont.) The best replication occurred at 1500 C and 1.5 MPa, and at these conditions channel depth was within 5% of the tool, and width was within 10%. For some processing conditions a smearing effect due to bulk material flow was observed. No upper limit on temperature was found, suggesting that fabrication processes in which the material is fully melted may also be suitable for fabrication of devices from TPEs.
by Megan Firko.
S.B.

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2

Zhao, Jie. "Hot embossing of polymeric tubular micro-components". Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27561.

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Technical and market demands of tubular micro-components have led to the development of a hot embossing process and corresponding machine for shaping polymeric micro-tubes. The targeted tubular micro-components are of an initial outer diameter of 1.6mm or below, and have reduced inner feature in the micron meter ranges. The proposed process feasibility study was supported by: 1) FE simulations using data obtained from material characterisation tests and 2) forming experiments and quality assessment of the formed components. Formability of more than ten types of polymeric micro-tubes were determined and their failure forms discussed. Furthermore, three forming mechanisms, namely plastic deformation, material flow and fusion bonding were identified and studied in detail. These studies allowed a fully functional machine to be developed, which has proved to be able to reliably produce 20 pieces parts per-minute when used with a continuous tube feeding system. The machine enabled a detailed process parameters study to be conducted in order to establish the factors influencing the final forming result. These consisted of two categories: the first category was Geometry Factors, which include the die-cavity geometry and tube inner/outer diameter ratio; the second category was Process Parameters, which include the forming temperature, maximum applied force, embossing velocity and dwelling time. The samples obtained were then evaluated through morphology examination, size measurement, microstructure and material flow analysis. The PTFE-a (outer diameter 1.2mm and inner diameter 0.6mm) and PP-a (outer diameter 1.3mm and inner diameter 0.6mm) micro-tubes have been successfully fabricated with desired features at temperatures of 200°C and 100°C respectively. The Polypropylene (PP) is considered as the most preferable material for hot embossing of tubular micro-components, due to its good ductility, low melting temperature and low viscosity. The results suggest that the proposed design can produce good performance with the correct combination of process parameters, tools and machine. The main outcomes from this research are: a novel micro-manufacturing process, material characterisation of polymeric micro-tubes, identification of the key hot embossing process parameters and their effects on the quality of the formed parts (especially the micro-scale features), a mass production solution, and a prototype desktop machine for industrial applications.

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3

Ganesan, Balamurugan 1976. "Process control for micro embossing : initial variability study". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/17925.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.
"June 2004."
Includes bibliographical references (leaves 178-182).
The objective of this research is to study the dimensional variations in micro embossed parts. By measuring multiple parts produced with a fixed set of control inputs, it could be determined if the process is in statistical control, if the parts produced have any noticeable trends and if there are any other forms of deterministic or assignable disturbances that were overlooked. The experiment resulted in 50 sets of data consisting of 10 runs, resulting in 50 control charts. By using both classic SPC rules for and by observation it was determined that about 42/50 control charts show traits of a process that is stationary and in-control. In the remaining 8 charts, some distinct trends were observable. These trends were postulated to be produced by unintentional disturbances caused by the experimental procedure. There were some distinct observable trends in the results from the experiment. The first is the location and frequency of the occurrence of the 8 distinctive run charts mentioned above and 4 run charts that were also observed to have marginally trend-like characteristic though it seems more data points are required to make a more sound judgment. Out of these 12 run charts, 9 of them are from the left side of the part. Out of this 9, 5 of them are from the 3rd feature scale. This trend leads to a conclusion that the disturbance responsible for this behavior is localized to a graphic region of that part. The second observable trend is the strong correlation between feature scale size and the mean of the die-part difference. As the feature size increases, the mean difference between the die and part measurement increases. This can be because bigger features involve a larger volume of polymer material to form the shape and as the material
(cont.) shrinks after being embossing and cooled, the reduction in relative dimension is greater. The third observable trend is the strong correlation between the feature scale size and the standard deviation of the die-part difference. The variance in this dimension is larger as the feature size increases. As larger features produce a larger mean die-part difference, this might also produce an opportunity for a larger variation in this measurement.
by Balamurugan Ganesan.
S.M.

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4

Shoji, Grant T. (Grant Tatsuo). "Modeling and control of a hot micro-embossing machine". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35621.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
"June 2006."
Includes bibliographical references (p. 268-273).
As the market for polymer micro- and nano-devices expands there is an ever-present need for a manufacturing standard to mass produce these parts. A number of techniques for fabricating these devices are soft lithography, micro-injection molding, and micro-embossing. Micro-embossing shows great promise in terms of versatility in creating various structures, but its shortcoming is a relatively long cycle time. Therefore, it is imperative to find efficient ways of heating and cooling in addition to having good control of critical processing parameters. This thesis will address the modeling and control of a hot micro-embossing system which utilizes oil as the heating and cooling medium. There were three thermal requirements addressed for the system: steady state temperatures within 1 C, fast as possible heating and cooling cycles, and being robust to various embossing and de-embossing processing temperatures. A model of the major thermal components in the system was developed and correlated well with experimental data. It was confirmed with simulation and experimentation that a lower flow rate achieved faster heating and a higher flow rate produced faster cooling. In order to address the steady state temperature requirement a variable gain PI controller was implemented.
(cont.) During heating the feedback signal was the platen temperature and during cooling the feedback signal was the mixing valve fluid outlet temperature. This variable gain PI controller in combination with the variable flow rates produced steady state temperatures for both platens from 55 to 120 °C within 1 C in 138 seconds. Cooling for both platens from 120 to 55 °C was achieved in 190 seconds. This controller worked for a variety of processing temperatures. A Labview interface was developed to automate this process for temperature step changes. Polymer microfluidic channels were successfully fabricated using this hot micro-embossing system with automated thermal control in a short cycle time.
by Grant T. Shoji.
S.M.

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5

Wang, Qi S. M. Massachusetts Institute of Technology. "Process window and variation characterization of the micro embossing process". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35651.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
"June 2006."
Includes bibliographical references.
The micro embossing process on polymethylmethacrylate (PMMA) is demonstrated experimentally to be a useful process to produce micro fluidic and optical devices. Because this process is a one step thermoplastic deformation process, it is possible to reach high production rates and low cost in manufacturing compared to the standard clean room processes. Currently, the research about this process is still on the feasibility level, with not a quantitative work to optimize the process parameters and assure product quality. In this thesis, an experimental study on process window and variation of Micro Embossing is presented. This study includes the design and manufacturing of an embossing die, the development of an embossing product quality assessment protocol, the process window characterization and the process variation identification. The research results based on the experimental set up in this thesis show that we should apply constant 800N embossing force at an embossing velocity of 1000N/min in order to obtain well formed parts to maintain low process cycle time.
(cont.) An embossing temperature of 120°C and de-embossing temperature of 55°C are shown to be the optimal embossing condition to yield good replication and repeatability. These embossing parameters operating window can change with the variation of working piece material, die material and die design.
by Qi Wang.
S.M.

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6

Dirckx, Matthew E. "Design of a fast cycle time hot micro-embossing machine". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32367.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2005.
"June 2005."
Includes bibliographical references (leaves 163-165).
In the coming years, there will be a huge market for mass-produced polymer micro- devices. These devices include microfluidic "labs on a chip," micro-optical chips, and many others. Several techniques exist for producing micron-scale features in polymer materials. One of the most promising of these techniques is Hot Micro-Embossing (HME). In this process, a thermoplastic polymer workpiece is heated above its glass transition temperature and a micro-patterned die is forced into it. The polymer conforms to the workpiece and the features are replicated. Much of the research to date concerning HME has not addressed fundamental issues that will be central to successful mass production using this process. There is a compelling need to study HME from the perspective of manufacturing process control. In order to conduct such a program, a HME machine is needed that allows the operator to precisely control all the potentially significant process parameters. No existing machine fully meets this requirement. This thesis concerns the conceptual and detailed design of a HME system, including the platen assembly and the temperature control system. A parametric model and finite element analysis were used to guide the design of the platen assembly and to assess its thermal and structural performance. A dynamic thermal model of the temperature control system was developed. This model was used to guide the selection of components and to predict the performance of the system as a whole. The new design will have a short cycle time, will permit the use of full wafer-size embossing tools, and will be able to follow a user- programmed trajectory in displacement, force, and temperature.
by Matthew E. Dirckx.
S.M.

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7

Taylor, Hayden Kingsley. "Modeling and controlling topographical nonuniformity in thermoplastic micro- and nano-embossing". Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54842.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 221-236).
The embossing of thermoplastic polymeric plates is valuable for manufacturing micro- and nanofluidic devices and diffractive optics. Meanwhile, the imprinting of sub-micrometer-thickness thermoplastic layers has emerged as a lithographic technique with exceptional resolution. Yet neither hot micro-embossing nor thermal nanoimprint lithography will be fully adopted without efficient numerical techniques for simulating these processes. This thesis contributes a computationally inexpensive approach to simulating the embossing of feature-rich patterns into thermoplastic polymeric materials. The simulation method employs a linear viscoelastic model for the embossed layer, and computes the distribution of contact pressure between the polymeric surface and an embossing stamp. An approximation to the embossed topography of the polymeric layer is thereby generated as a function of the material being embossed, the stamp's design, and the embossing process's temperature, duration, and applied load. For a stamp design described with an 800 x 800 matrix of topographical heights, simulation can be completed within 30-100 s using a computer with an Intel Pentium 4 processor and 2 GB RAM. This method is sufficiently fast for it to be employed iteratively when designing a pattern to be embossed or when selecting processing parameters. The method is able to build abstracted representations of feature-rich patterns, increasing the simulation speed still further. The viscoelastic properties of three materials - polymethylmethacrylate, polycarbonate, and Zeonor 1060R, a cyclic olefin polymer - have been experimentally calibrated as functions of temperature. For a test-pattern having features with diameters 5 [mu]m to 90 [mu]m, simulated and experimental topographies agree with r.m.s. errors of less than 2 [mu]m across all processing conditions tested, with absolute topographical heights ranging up to 30 [mu]m. In thermal nanoimprint lithography, the key challenge is to minimize spatial variation of the polymeric layer's residual thickness where stamp protrusions press down into the layer. The simulation method is therefore extended to incorporate elastic stamp deflections and their influence on residual layer thickness. Some design-rules are proposed that could help to minimize residual layer thickness variation. A way is also proposed for representing any shear-thinning of the imprinted layer.
by Hayden Kingsley Taylor.
Ph.D.

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8

Thaker, Kunal H. (Kunal Harish). "Design of a micro-Functional Testing System for process characterization of a hot micro-embossing machine". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35647.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
"June 2006."
Includes bibliographical references (p. 279-284).
Growth in industrial, commercial, and medical applications for micro-fluidic devices has fueled heightened research and development into micro-fluidic design, materials, and increasingly manufacturing. Polymers (Poly(methyl methacrylate)-PMMA in particular) are the current material of choice given their low cost, wide range of material properties, and biocompatibility. Given most fabrication processes have focused on hard materials for the semiconductor industry, an alternate set of processes such as hot micro-embossing (HME) have received increased attention as manufacturing processes for high-volume polymer-based micro-fluidic production. An understanding of the equipment, process physics, control strategy, and metrology for part fabrication are required when moving from the lab to production level. An initial statistical analysis of PMMA parts fabricated on the first generation HME system showed the need to: (1) design a new HME system; and (2) establish alternative methods for characterizing micro-fluidic parts.
(cont.) A second generation HME system was constructed with fellow Manufacturing and Process Control Laboratory (MPCL) graduate students and a FTS (Functional Testing System) was developed to test whether HME parts from the new HME system were capable of flowing fluid and establish output metrics for process control based on fluid pressure and flow rate. The new characterization method was shown to have re-registration error as low as + 1.03% (overall RMS uncertainty of ±1.51%). The experimental data from tests run on the FTS fit a fluid model developed to the expected accuracy of --± 10% for all but the lowest aspect ratio micro-channel. Moreover, the FTS results were consistent with optical scans of a series of parts made with varying HME parameters. The FTS was able to detect differences that a few isolated optical scans could not. The FTS provided a bulk quantity to assess the geometry of the channel rather than at a specified location. These results and the deficiencies in existing metrology techniques warrant further exploration into functional-based testing for micro-fluidic devices to parallel well established testing methods in place in the IC industry. Functional testing does not have the capacity to replace traditional metrology; however, it can add an important output metric-a quantitative measure of the output parts fluid flow.
by Kunal H. Thaker.
S.M.

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9

Lu, Chunmeng. "Development of novel micro-embossing methods and microfluidic designs for biomedical applications". Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1156820643.

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10

Nagarajan, Pratapkumar. "Rapid production of polymer microstructures". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26539.

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Thesis (Ph.D)--Polymer, Textile and Fiber Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Dr. Donggang Yao; Committee Member: Dr. John.Muzzy; Committee Member: Dr. Karl Jacob; Committee Member: Dr. Wallace W. Carr; Committee Member: Dr. Youjiang Wang. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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11

Bhatia, Rikki. "Daylighting applications of micro-textured optical surfaces". Thesis, Brunel University, 2001. http://bura.brunel.ac.uk/handle/2438/5146.

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Daylighting is the use of natural light to replace artificial light. In traditional rooms sunlight will only illuminate the area closest to the window due to the high solar angle. The rear of the room appears gloomy and occupants will use electric lighting even though there is sufficient daylight to illuminate the interior. The first section of this thesis reports on the application of micro-prisms to glazing. Such systems could improve the penetration of the light and reduce the energy bill. Fig 1: (Left): A traditional window. (Right) A window with the top third coated in microprisms. The aim of the work is to develop suitable structures than can be easily and cheaply mass produced using an industrial UV embossing process. Whenever possible the requirements of this process dictate the physical characteristics of the microstructures. The development process includes all the stages from design to full-scale testing of the prototypes in an office. Several different mechanical methods are used to produce prismatic arrays that conform to an initial design calculation. Each sample is evaluated in terms of its physical characteristics, its optical properties and finally its ability to improve illumination within a room. The latter aspect is determined, not only by measurement, but also the subjective assessment of occupants. The second micro-textured surface to be examined is the microlens. Three systems are investigated: - A controlled diffuser incorporating cylindrical lenses to improve the distribution of the daylight. - An afocal pair of lenses to improve the penetration of daylight through beam-steering. - An angular filter to exclude direct sunlight while admitting diffuse light. Most of the research is concerned with the third system. On sunny days windows can cause sufficient glare that occupants will pull the venetian blinds. Not only will this exclude the direct sunlight but also the diffuse daylight, cause darkening of the room and leading to the use of artificial light. The angular filter or 'solar shade' uses microlenses to image the direct sunlight which can then be blocked by circular obturations. The diffuse sunlight is not focused and therefore transmitted so the room is not darkened. The research is based on experimentation with small-scale systems and computer modelling to optimise the system. The results show potential improvements over new 'smart' windows although mechanical tolerances are high.

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Ames, Nicoli M. (Nicoli Margret) 1978. "A thermo-mechanical finite deformation theory of plasticity for amorphous polymers : application to micro-hot-embossing of poly(methyl methacrylate)". Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42068.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references.
Amorphous thermoplastic polymers are important engineering materials; however, their nonlinear, strongly temperature- and rate-dependent elastic-visco-plastic behavior has, until now, not been very well understood. The behavior has previously been modeled with mixed success by existing constitutive theories. As a result, there is currently no generally agreed upon theory to model the large-deformation, thermo-mechanically coupled, elasto-visco-plastic response of amorphous polymeric materials spanning their glass transition temperatures. What is needed is a unified constitutive framework that is capable of capturing the transition from a visco-elastic-plastic solidlike response below the glass transition temperature, to a rubbery-viscoelastic response above the glass transition temperature, to a fluid-like response at yet higher temperatures. We have developed a continuum-mechanical constitutive theory aimed to fill this need. The theory has been specialized to represent the salient features of the mechanical response of poly(methyl methacrylate) in a temperature range spanning room temperature to 60C above the glass transition temperature #g 110C of the material, in a strain-rate range of 10-4/s to 10-1/s, and under compressive stress states in which this material does not exhibit crazing. We have implemented our theory in the finite element program ABAQUS/Explicit. The numerical simulation capability of the theory is demonstrated with simulations of the micron-scale hot-embossing process for manufacture of microfluidic devices.
by Nicoli Margaret Ames.
Ph.D.

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13

Zhang, Jie. "Contribution aux développements des technologies de compression polymères chargés pour la réalisation d'inserts métalliques micro-structurés". Thesis, Besançon, 2013. http://www.theses.fr/2013BESA2044/document.

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Les travaux menés dans le cadre de cette thèse sont focalisés sur les procédés deréplication permettant la transformation des mélanges en composants par les technologiesen séquentiel ou bien en continu, selon les applications visées. Les développementsconcernent la mise en place et l’hybridation de différents procédés de micro-réplication(estampage à chaud de polymère thermoplastique et par laminage circulaire entre deuxrouleaux). Ces deux procédés sont développés et optimisés pour l’élaboration decomposants micro-structurés ou de microcomposants possédant des propriétésfonctionnelles mécaniques ou thermo-physiques requises à partir de différents mélangeschargés en poudres métalliques ou en nanotubes de carbone. Des exemples de réalisationde composants structurés, à base d’un système micro-fluidique possédant plusieurs canauxde 200 microns par 200 microns et des réservoirs de diamètre de 2 mm, sont prises commeexemple tout au long de ces travaux de cette thèse. Différents travaux de caractérisationsont été entrepris pour optimiser les procédés de micro-réplication par estampage à chaud etpar laminage circulaire entre deux rouleaux
The Ph.D subject concerns the study of two micro-replication processes by hotembossing and roll to roll processes for thermoplastic polymers and loaded polymers withpowders or carbon nanotubes. The micro-replication processes, realized in sequential orcontinuous ways, use some different elaborated loaded feedstocks in order to obtainstructural components or micro-component with high aspect ratio and mechanical orthermo-physical properties.A chain combining hot embossing and roll embossing and powder metallurgy have beendeveloped in our lab and investigated. The different micro mould die cavities have beenrealized with different micro-manufacturing process, elastomeric mould has been obtainedby casting process. Finally, a metallic structured die cavity has been obtained by combininghot embossing and debinding and sintering stages. The second topic is the comparison ofmetallic die cavity mould obtained by roll embossing or rolls embossing. Two demonstratorshave been developed during the preparation of this Ph.D period: first a metallic micro-fluidicsystem with micro-structuration with diameter of 1 mm for the reservoir and 200 microns by200 microns for the channel have been realized and characterized by different methods.Secondly, some functional micro-component has been obtained with carbon nanotube andsome specific properties in terms of mechanic and thermo-physical properties have beencharacterized

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14

Shu, Cheng-Gang. "Modélisation physique, simulation numérique et investigation expérimentale de l'estampage à chaud des polymères thermoplastiques amorphes". Thesis, Besançon, 2014. http://www.theses.fr/2014BESA2004/document.

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Le procédé d’estampage à chaud est considéré comme l'un des procédés les plus prometteurs de micro-Réplication pour l'élaboration des micro-Composants ou nano-Composants avec des matériaux polymériques dans différents domaines d'application . La mémoire consiste à caractériser les propriétés physiques des polymères thermoplastiques amorphes (PS, PMMA et PC) sur une large plage de température, ainsi que la modélisation physique, la simulation numérique et vérification expérimentale du procédé d’estampage à chaud.[...]Les propriétés visco élastiques des polymères retenus ont été caractérisées avec les essais décompression dynamiques. Le module de conservation, le module de perte et le facteur d'amortissement de polymère PMMA à partir de la température ambiante jusqu'à légèrement au-Dessus de Tg ont été obtenues. Le comportement visco élastique des polymères a été décrit par un modèle de Maxwell Généralisé et un bon accord a été observé. La simulation numérique des étapes du remplissage de procédé d’estampage à chaud a été réalisée enprenant compte des propriétés visco élastiques de polymère. Les effets de la température et dela pression de compression sur l'exactitude de réplication dans le procédé d’estampage à chaud ont été étudiés.[...]Un nouveau moule de compression complet, y compris le système de chauffage, le système de refroidissement et le système de vide a été développé dans notre groupe de recherche. Les dispositifs micro fluidiques avec la dimension de la cavité : environ 200 μm, 100 μm et 50 μmen PS, PMMA et PC plaque (épaisseur de 2 mm) ont été élaborés par le procédé d’estampage à chaud. Les effets des paramètres du procédé, tels que l’entrefer imposé, la température décompression, la matière compressée et la dimension de micro cavité, sur l’exactitude de réplication du procédé d’estampage à chaud ont été étudiés
Hot embossing process is considered as one of the most promising micro replication processes for the elaboration of micro or nano components with polymeric materials invarious application fields. The thesis consists to characterize the physical properties of widelyused amorphous thermoplastic polymers (PS, PMMA and PC) over a large temperature range,along with the physical modelling, numerical simulation and experimental verification of thehot embossing process.[...] The polymers’ viscoelastic properties have been characterized with the dynamical compression tests. The storage modulus, loss modulus and damping factor of PMMA polymerfrom ambient temperature to lightly above Tg have been obtained. The viscoelastic behaviourof polymer has been described by a proposed Generalized Maxwell model and a good agreement has been observed. The numerical simulation of filling stage of hot embossing process has been achieved by taking into account of polymer’s viscoelastic properties. Theeffect of compression temperature and pressure on the replication accuracy in hot embossing process has been investigated in the simulation.[...] A new complete micro compression mould tools, including heating system, cooling system and vacuum system have been developed in our research group. The microfluidic devices with the cavity dimension eq. to about 200 μm, 100 μm and 50 μm in PS, PMMA and PC plate(thickness eq. to 2 mm) have been elaborated by the hot embossing process. The effects of the processing parameters, such as the compressive gap imposed, compression temperature, embossed material and die cavity dimensions, on the replication accuracy of hot embossing process have been investigated

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15

Thieme, Michael, Christa Blank, de Oliveira Aline Pereira, Hartmut Worch, Ralf Frenzel, Susanne Höhne, Frank Simon, Lewis Hilton G. Pryce y Aleksandr J. White. "Superhydrophobic Aluminum Surfaces: Preparation Routes, Properties and Artificial Weathering Impact". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-107085.

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Among the materials that can be treated in order to impart superhydrophobic properties are many originally hydrophilic metals. For this, they must undergo a sequential treatment, including roughening and hydrophobic coating. This contribution presents various preparation routes along with various characterization methods, such as dynamic contact angle (DCA) measurements, scanning electron microscopy (SEM) and spectroscopic techniques (FT–IRRAS, XPS, EIS). Micro-rough surfaces of pure and alloyed aluminum were generated most easily by using a modifie Sulfuric Acid Anodization under Intensifie conditions (SAAi). This produces a micro-mountain-like oxide morphology with peak-to-valley heights of 2 μm and sub-μm roughness components. Additionally, micro-embossed and micro-blasted surfaces were investigated. These micro-roughened initial states were chemically modifie with a solution of a hydrophobic compound, such as the reactive f uoroalkylsilane PFATES, the reactive alkyl group containing polymer POMA, or the polymer Teflo ® AF. Alternatively, the chemical modificatio was made by a Hot Filament Chemical Vapor Deposition (HFCVD) of a PTFE layer. The latter can form a considerably higher thickness than the wet-deposited coatings, without detrimental leveling effects being observed in comparison with the original micro-rough surface. The inherent and controllable morphology of the PTFE layers represents an important feature. The impacts of a standardized artificia weathering (WTH) on the wetting behavior and the surface-chemical properties were studied and discussed in terms of possible damage mechanisms. A very high stability of the superhydrophobicity was observed for the f uorinated wet-deposited PFATES and Teflo ® AF coatings as well as for some of the PTFE layer variants, all on SAAi-pretreated substrates. Very good results were also obtained for specimens produced by appropriate mechanical roughening and PTFE coating.

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16

Thieme, Michael, Christa Blank, de Oliveira Aline Pereira, Hartmut Worch, Ralf Frenzel, Susanne Höhne, Frank Simon, Lewis Hilton G. Pryce y Aleksandr J. White. "Superhydrophobic Aluminum Surfaces: Preparation Routes, Properties and Artificial Weathering Impact". Technische Universität Dresden, 2009. https://tud.qucosa.de/id/qucosa%3A26716.

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Among the materials that can be treated in order to impart superhydrophobic properties are many originally hydrophilic metals. For this, they must undergo a sequential treatment, including roughening and hydrophobic coating. This contribution presents various preparation routes along with various characterization methods, such as dynamic contact angle (DCA) measurements, scanning electron microscopy (SEM) and spectroscopic techniques (FT–IRRAS, XPS, EIS). Micro-rough surfaces of pure and alloyed aluminum were generated most easily by using a modifie Sulfuric Acid Anodization under Intensifie conditions (SAAi). This produces a micro-mountain-like oxide morphology with peak-to-valley heights of 2 μm and sub-μm roughness components. Additionally, micro-embossed and micro-blasted surfaces were investigated. These micro-roughened initial states were chemically modifie with a solution of a hydrophobic compound, such as the reactive f uoroalkylsilane PFATES, the reactive alkyl group containing polymer POMA, or the polymer Teflo ® AF. Alternatively, the chemical modificatio was made by a Hot Filament Chemical Vapor Deposition (HFCVD) of a PTFE layer. The latter can form a considerably higher thickness than the wet-deposited coatings, without detrimental leveling effects being observed in comparison with the original micro-rough surface. The inherent and controllable morphology of the PTFE layers represents an important feature. The impacts of a standardized artificia weathering (WTH) on the wetting behavior and the surface-chemical properties were studied and discussed in terms of possible damage mechanisms. A very high stability of the superhydrophobicity was observed for the f uorinated wet-deposited PFATES and Teflo ® AF coatings as well as for some of the PTFE layer variants, all on SAAi-pretreated substrates. Very good results were also obtained for specimens produced by appropriate mechanical roughening and PTFE coating.

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17

Aor, Bruno. "Engineering microchannels for vascularization in bone tissue engineering". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0430/document.

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In vitro, la formation de structures de type tubulaire avec des cellules endothéliales de veine ombilicale humaine (HUVEC) a été étudiée en combinant la fonctionnalisation de la chimie des matériaux et le développement de la géométrie tridimensionnelle. Le polycarbonate (PC) a été utilisé comme modèle pour le développement de l'échafaud. Le film de polysaccharide naturel, basé sur un dépôt alternatif couche par couche (LbL) d’acide hyaluronique (HA) et de chitosane (CHI), a d’abord été appliqué sur une surface PC et caractérisé en termes de croissance d’épaisseur microscopie à balayage lascar (CLSM). Cette première fonctionnalisation se traduit par un revêtement complet de la couche PC. Une biofonctionnalisation supplémentaire avec un peptide adhésif (RGD) et deux peptides angiogénétiques (SVV et QK) a été étudiée, immobilisant ces peptides sur le groupe carboxylique de HA précédemment déposé, en utilisant la chimie bien connue du carbodiimide. La version marquée de chaque peptide a été utilisée pour caractériser l’immobilisation et la pénétration des peptides dans les couches de polyélectrolytes, aboutissant à une greffe réussie avec une pénétration complète dans toute l’épaisseur du LbL. Des tests in vitro ont été effectués à l'aide de cellules HUVEC pour évaluer leur efficacité d'adhésion et leur activité métabolique sur la LbL avec et sans immobilisation de peptides, ce qui a permis d'améliorer l'activité préliminaire lorsque des combinaisons de peptides sont utilisées. Enfin, les micro-canaux PC (μCh) ont été développés et caractérisés pour la première fois, et les autres expériences ont été réalisées sur un micromètre de 25 μm de largeur, fonctionnalisé avec une architecture (HA / CHI) 12,5 (PC-LbL) avec des peptides RGD et QK -RGD + QK) ou avec des peptides RGD et SVV (PC-RGD + SVV). Notre première expérience de tubulogénèse a montré de manière surprenante la formation de structures de type tubulaire déjà après 2h d'incubation en utilisant la combinaison double-peptides, mais uniquement avec PC-RGD + QK. Les tubes étaient également présents après 3 et 4 heures de culture. L'expérience de co-culture avec des péricytes humains dérivés du placenta (hPC-PL) montre comment la stabilisation des tubes a été améliorée après 3 et 4 heures également pour l'échantillon de PC-RGD + SVV. Globalement, notre matériel bio-fonctionnel avec les peptides PC-RGD + QK et PC-RGD + SVV permet la formation d'une structure de type tubulaire à la fois dans une expérience de monoculture et de co-culture
In vitro, tubular-like structures formation with human umbilical vein endothelial cells (HUVECs) was investigated by combining material chemistry functionalization and three-dimensional geometry development. Polycarbonate (PC) was used as a template for the development of the scaffold. Natural polysaccharide’s film based on alternate layer-by-layer (LbL) deposition of hyaluronic acid (HA) and chitosan (CHI), was first applied to PC surface and characterized in terms of thickness growth both, in dry conditions using ellipsometry, and confocal lascar scanning microscopy (CLSM). This first functionalization results in a complete coating of the PC layer. Further biofunctionalization with one adhesive peptide (RGD) and two angiogenetic peptides (SVV and QK) was investigated, immobilizing those peptides on the carboxylic group of HA previously deposited, using the well-known carbodiimide chemistry. The labeled version of each peptide was used to characterize the peptides’ immobilization and penetration into the polyelectrolytes layers, resulting in a successful grafting with complete penetration through the entire thickness of the LbL. In vitro tests were performed using HUVECs to assess their adhesion efficiency and their metabolic activity on the LbL with and without peptide immobilization, resulting in a preliminary improved activity when peptide-combinations is used. Finally, PC micro-channels (μCh) were first developed and characterized, and the rest of the experiments were performed on μCh of 25μm width, functionalized with (HA/CHI)12.5 architecture (PC-LbL) with RGD and QK peptides (PC-RGD+QK) or with RGD and SVV peptides (PC-RGD+SVV). Our first tubulogenesis experiment surprisingly showed the formation of tubular-like structures already after 2h of incubation using the double-peptides combination but only using PC-RGD+QK the tubes were present also after 3 and 4 hours of culture. The co-culture experiment with human pericytes derived from placenta (hPC-PL) demonstrates how the stabilization of the tubes was improved after 3 and 4 hours also for the PC-RGD+SVV sample. Globally our bio-functional material with PC-RGD+QK and PC-RGD+SVV peptides allow the formation of tubular-like structure in both mono and co-culture experiment

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18

Hardt, David E., Bala Ganesan, Matthew Dirckx, Grant Shoji, Kunal Thaker y Wang Qi. "Process Variability in Micro-Embossing". 2004. http://hdl.handle.net/1721.1/7463.

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A promising technique for the large-scale manufacture of micro-fluidic devices and photonic devices is hot embossing of polymers such as PMMA. Micro-embossing is a deformation process where the workpiece material is heated to permit easier material flow and then forced over a planar patterned tool. While there has been considerable, attention paid to process feasibility very little effort has been put into production issues such as process capability and eventual process control. In this paper, we present initial studies aimed at identifying the origins and magnitude of variability for embossing features at the micron scale in PMMA. Test parts with features ranging from 3.5- 630 µm wide and 0.9 µm deep were formed. Measurements at this scale proved very difficult, and only atomic force microscopy was able to provide resolution sufficient to identify process variations. It was found that standard deviations of widths at the 3-4 µm scale were on the order of 0.5 µm leading to a coefficient of variation as high as 13%. Clearly, the transition from test to manufacturing for this process will require understanding the causes of this variation and devising control methods to minimize its magnitude over all types of parts.
Singapore-MIT Alliance (SMA)

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19

shje, Jeng-Luen y 謝正倫. "Development of Rolling Micro-Embossing Process". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/27574332350020514061.

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碩士
國立臺灣大學
機械工程學研究所
93
This thesis is devoted to the development of rolling micro-embossing process.Conventional rolling embossing can fast transform micro-structure on substrate, it is only limited to flexible substrate at present. In order to solve present shortcoming and restriction, one innovative method of rolling micro-embossing process was developed. The process is a carried out by applying a constant force over the roller stamp, forcing it to contact the resin-coated glass substrate and applying UV light from bottom of substrate. Three different kinds of pattern have been transferred completely on the photoresist :(i) 30×80μm dimension、40μm deep grating structure(ii)100μm diameter、21μm deep microlens array and (iii) 58μm wide、6μm deep micro U-groove features. Non-uniform pressure distribution is a problem when only nickel mould is wrapping around the 56mm diameter,160mm long steel roller. The nickel mold size is 40×40 mm and 150μm thick. By wrapping cushion pad around steel roller before attaching the nickel mold to uniform imprinting pressure throughout the whole area can be achieved. In order to reduce the sticking problem between the resist and mold, the mold was pretreated with a mold release agent Teflon. In this study, it is found that the platform speed is the most important processing parameter since curing time is critical. The micro-structure can be replicated when platform speed is between 0.5~2.1mm/s. The embossing pressure should be above 1.2kgf/cm2 to achieve uniform pressure.

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20

Emadinia, Omid. "Micro hot embossing of metallic reinforced powders". Tese, 2018. https://repositorio-aberto.up.pt/handle/10216/116390.

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21

Emadinia, Omid. "Micro hot embossing of metallic reinforced powders". Doctoral thesis, 2018. https://repositorio-aberto.up.pt/handle/10216/116390.

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22

Ciou, Jyun-Kai y 邱俊凱. "Development of CO2 gas-assisted micro embossing process". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/36277507860391907741.

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碩士
臺灣大學
機械工程學研究所
95
In conventional hot embossing, the polymer substrate is first heated to a temperature higher than its glass transition temperature(Tg); the substrate and the stamp are then brought into contact and are compressed directly by the hot plates. The accuracy and area of replication are limited due to the inherent non-uniform pressure distribution of the hot-plate compression. Besides, materials such as Si-wafers and glass are too brittle to be used as the embossing molds in the conventional hot embossing operation. This paper reports the development of a CO2–assisted embossing process. Since CO2 is a good solvent for polymers such as PMMA, it can serve as the plasticizing agent to soften the substrate; the embossing temperature can be operated below Tg, even at room temperature. Furthermore, CO2 is used as the pressing medium. The distribution of gas pressure is uniform, the process is advantageous to large-area imprinting. The Si and glass-based materials can be used as embossing mold. The results show that patterns can be transferred onto the surface of polymer substracts with low pressure at a temperature below Tg. The low-temperature and low-pressure imprinting can reduce residual stress and shrinkage of the embossed substrates. The sub-micron patterns can even be transferred onto the surface of polymer substracts at room temperature﹗ For replicating microstructure with deeper patterns, higher temperature and absorption pressure are needed. In this study, the CO2-assisted embossing method has been successfully employed to fabricate optical components including brightness enhancement film, light guiding plate, VCD micro-patterns, micro lens arrays, and Fresnel lens. CO2-assisted micro-embossing has been proven to be an effective and efficient process for replicating microstructured-parts with low residual stress at low-temperature and with low-pressure.

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23

Liao, chien-ting y 廖健廷. "Replication of Micro-structures by Soft-Mold Embossing". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/82138339164013139958.

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碩士
長庚大學
機械工程研究所
96
Abstract Following the technical evolution of the Micro-Electro-Mechanical System (MEMS), manufacturing technics has continuously been innovating and microlizating, but the expensive equipment and complicated manufacturing process have always been very high threshold. The Soft-Lithography is a kind of developed nano replicated technics from MEMS. Using the Soft-mold methodology to replicate a soft graphic mold, and using the mold to print the graph. The whole process use a simple, quick and non-expensive equipment, and with very convenience. In this paper, it is combining the Roller and Soft-mold as a tool to develop a roller soft-mold printing machine with multiple printing function and drawknife system. Using the UV resin the to print the micro structure based on UV-curing principle, trying to measure and record the printing structure, and study several parameters which may impact the printing micro structure to improve the printing process. In the research process, we can find the UV resin with high viscosity has better replication, but it may has the defect of bubbles, and the lower viscous UV resin has the contrarily effect. Using the soft-mold printing to fill the material into the formed mold cave structure could provide a kind of brand new filling manufacturing process to apply in manufacturing the optical elements.

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24

Chang, Ya-Ping y 張亞平. "Effect of laser and embossing condition on the superstructure of micro-embossing molded product of polymer". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/17652722394803217122.

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碩士
國立交通大學
機械工程系所
97
The superstructure of the polymer materials will be different with different process. The hot embossing mold usually use pressure and temperature to control, but this is not enough to produce the functional materials. In recent years, the researches show that added energy field on the structure of polymer materials in forming stage,it had changed the material property. We can use it to manufacture the different superstructure, so the effect of the extra energy field is very important for the functional materials. In this study, we observed the effect of laser and hot embossing condition on the superstructure of micro-embossing molded product of polymer. In the result of the experiment, we can find that the inside of the product will be divided into three layers without shear force. Three layers are formed from the lateral surface to the interior: the surface layer, the middle layer, and the core layer. The proportion of each thickness of these three types of layers in a cross section is about 1:1.2:13.6. The superstructure of the layers would be changed with changing embossing pressure and cooling rate. In high temperature and slow cooling rate, the materials shrinkage of the irradiated department and the degree of crystallization would be decreased by laser beam irradiation.

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25

JHANG, JIA-MING y 張家銘. "A Study of Micro Embossing Process on Aluminum 1100". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/28537568474594665335.

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碩士
國立臺灣科技大學
機械工程系
101
Due to the trend of miniaturization, the need of small metallic components has been being tremendously increased. Among the micro manufacturing processes, microforming is the most cost effective process to fabricate micro metallic parts in mass production. In this thesis, micro embossing process was investigated through a series of experiments in which the MTS Criterion Series 43 machine was used as a forming press, and the annealed aluminum sheets (1mm) were deformed into micro channels by three micro-channel dies (1.0mm, 0.8mm and 0.6mm channel widths) under different compressive forces. In order to study the influence of the size effects on micro embossing process, the aluminum sheets were annealed at five different temperatures (600oC, 550oC, 500oC, 450oC, and 400oC) for obtaining different grain sizes such that different sheet thickness to average grain diameter ratios（T/D ratios）can be obtained. T/D ratio can be used as a parameter to model size effects. The physical meaning of T/D ratio is the total number of the grains throughout the material thickness. The experimental parameters for this study include T/D ratio, compressive force and channel width. It was found that the compressive force is the most critical parameter for forming aluminum micro channels by using micro embossing process. In addition, under the same forming conditions, the deformed channel depth increases with increasing channel width of the die, but it reduces with increasing T/D ratio. Finally, an optimal combination of these parameters was obtained.

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26

Tsai, Ming-Yen y 蔡明諺. "Development of curved PVDF diaphragm devices with micro embossing method". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/80150012819693604652.

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碩士
國立中正大學
機械系
99
In this paper, the main contents of we talk about is the piezoelectric polymer film “Polyvinylidene fluoride, PVDF”. Because the PVDF film has high flexibility and impact resistance, micro-embossing is proceeded from the mold that using the photo-lithography technology to fabricate. Then the PVDF film can be transformed from a flat surface into a wavy structure. With the wavy structure of PVDF film, we can develop two applications: 1. Acoustic Emission Sensor: By using the developed micro-embossing fabrication method, the multi-layer piezoelectric polymer (PVDF) thin films can be structured as a wavy shaped sensing core element. Also, we have successfully developed the AE sensor, and used the device for a number of experimental test. In steel ball test, we found the device have better signal to noise ratio (5.9 > 1.2) and wide bandwidth (50 ~ 1400 KHz > 100 ~ 900 KHz) and cheap than the commercially available AE sensors. Finally, in the bearing wear experimental, the wavy shaped sensors can distinguish between different degrees of bearing wear. 2. Piezoelectric Generators: When the PVDF piezoelectric film after embossing, we coat PDMS from the unit piezoelectric generator elements. We test the unit using a home-made road-simulation system. Through different vibration level caused by the bumps on the route. The unit can generate electrical power via mechanical energy conversion. With stacking 6 elements layer-by-layer, a 1.7V LED will be light up. Therefore, the generator function is proved. And, it have maximum power (4.487μW) when the loading is 3.9 MΩ, to provide a new direction for the clean energy collection.

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27

Gao, Jiang-Hao y 高疆濠. "The Study of Virtual assisted micro hot embossing learning platform". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/96734356457361872739.

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碩士
龍華科技大學
機械系碩士班
94
Micro hot embossing is a newly developed technology for accuracy production. It has been applied for the production of optics component with high precision and products with micro features. Due to the extremely high cost for an embossing machine, it is practically not suitable for new uses to occupy the machine to be familiar with the operation procedures and parameter settings. This research developed a virtual machine and environment for hot embossing for the purpose of unconfined use of such machines for training. This virtual platform was built by the virtual reality technology on PC. 3D max was used to construct the scene and 3-D objects. Software for virtual reality, EON, imports the virtual scene and objects to arrange the object movements and response in the virtual environment. A computer code written in Visual Basic is used as user interface and the logic controller. This platform contains four parts, namely fundamental introduction to the machine, theory introduction of, operation procedure training, and parameter setting. Figure-reminder, voice reminder and text-reminder are used in the learning platform to help the users in their learning. Through the using of this platform, users become experienced operators of the machines. This platform is also tested and proved for its effectiveness in learning. The feedback from the user shows that this learning system is very effective in helping un-experienced person in the adept learning of the embossing system.

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28

王計堯. "Development of Graphene Rapid Heating TechnologyApplied to Micro hot embossing". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/bmyssn.

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碩士
國立高雄應用科技大學
模具工程系
106
Thin plastic microlens array component have been widely used in various fields in recent years, such as: LED lighting systems, flat panel displays, optical projectors, optoelectronic communication devices and high-efficiency solar panels, while micro-thermal forming processes are producing these One of the key technologies for thin plastic micro-array array components is because of its low equipment cost and simple process steps, which is very suitable for mass production of thin and large-area plastic microstructure array components. However, the traditional micro-hot press forming technology has the disadvantages of slow lifting temperature and time-consuming process cycle, so it often seriously affects the production efficiency of the product. In view of this, this study intends to develop graphene rapid heating technology to improve the lack of traditional micro-heat press process, and hope to successfully improve the production efficiency of micro-hot press forming. The specific measure of this study is to directly apply the liquid graphene conductive ink to the high temperature resistant PI film. After proper baking and electronic packaging, the graphene film heating with excellent electrothermal and thermal conductivity can be obtained. In this study, we will plan experiments to produce graphene film heaters with different film thicknesses and areas, and then control the temperature rise and temperature of the DC power supply through the modulation of the voltage and current of the DC power supply. Finally, this study verified the use of graphene thin film heaters by using the micro-hole array mold and the micro-thermoforming process of the plastic substrate. The micro-thermal pressure test results confirmed that the technology can produce plastic microlens array elements in a short time. The optical components are tested for optical properties, and the microlens has excellent focusing and imaging functions, thereby successfully verifying the feasibility of the rapid heating of graphene for micro-compression molding.

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29

Peng, Wei-Long y 彭偉隆. "Research of optical micro lens array by hot embossing technique". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/07069555564219333476.

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碩士
國立交通大學
工學院半導體材料與製程設備學程
100
This study uses ultra-precision machining production of micro-lens array structure in the absence of electroless nickel materials. The size of the microlens array is 8.7μm deep, 180μm wide, and the spacing between the lens are 320μm. And choice 1 mm thick of Poly methyl-methacrylate (Commonly known as PMMA) sheet as a micro hot embossing material. This study for different conditions on the microlens array, including the lens length, width and depth of 3D laser confocal microscopy measured the conclusion that the best process parameters. We found that hot embossing temperature and force are the key parameters of the components transcription rate. When the temperature of 160℃, the microlens array and transcription rate increased with hot embossing forces increase and reach the saturation value of 1.0 kN. Finally, the hot embossing temperature under 160℃,force 1.0kN complete height 8.512μm、transcription rate 98.27% of the microlens array.

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30

Huang, Zhong-yue y 黃仲岳. "Study of the Micro Hot-embossing Process for Microlens Fabrication". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/49893160134641369134.

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碩士
國立高雄第一科技大學
機械與自動化工程所
95
This paper investigates microlens fabrication using micro hot-embossing process.Under the scaling law effect, both the height and radius of curvature of the microlens produced by micro hot-embossing are in connection with surface tension.When surface tension increases, the microlens height increases but the radius of curvature decreases.In order to understand the effect of surface tension,simulations of hot-embossing microlens are conducted using Marc simulation softwares are performed, and to fabricate a microlens with designated specifications(ie,height,radius of curvature and focal length),Marc simulations adopting the Taguchi method are carried out to obtain the optimal micro hot-embossing parameters and the experimental verification is then provided.In such away,the development time for microlesns fabrication can by highly reduced.

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31

Wang, Ying-Chieh y 王膺傑. "Study on Hot Embossing Characteristics in Micro-channel for Biochip". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/41967592006585293232.

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碩士
中原大學
機械工程研究所
94
Polymers have a great potential to be used for BioMEMS applications because many polymers are low cost, can be processed easily, and possess a broad range of physical and chemical properties. In this study, the micro-channel array with 30μm in depth, 100μm in width and 50μm in pitch had designed. And another pattern with different aspect ratio had also designed. The UV light was used to transfer the pattern on SU-8 photoresist, and the Ni-Co based stamp was made by electroforming. PMMA and PC sheet of 70 ㎜ and 45㎜in diameter and 1 mm in thickness was utilized as molding substrate. 3D laser microscope was used to measure the width, depth and sidewall draft angle of the micro-channels. The processing conditions studied include embossing force, embossing temperature, and embossing time. It was found that embossing force and embossing temperature are two key parameters affecting the molding accuracy significantly. Increasing embossing temperature will make the melt more soften and lower the viscosity of melt to reach good accuracy of imprint depth and width, but the cycle time also increased. All the accuracies of the imprint depth, width and draft angle increase with the applied embossing force until the associated dimensions reach saturated values. Increase of embossing time would increase the replication accuracy. Different aspect ratio micro-channels molding experimental shows that small channel is easily molding. From this study, it will lead to a better understanding on the molding characteristics of hot embossing for the fabrication of micro-channels within a polymer substrate. The study also provides research worker a molding guideline for molded biochip devices.

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32

Lou, J. D. y 羅金德. "Ultrasonic Vibration Heated Hot Embossing of Plastic Plates with Micro-features". Thesis, 2002. http://ndltd.ncl.edu.tw/handle/94297310867898770439.

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碩士
國立臺灣大學
機械工程學研究所
90
Hot embossing has excellent performance in replicating precise micro-feature into large plastic plates. It has become a popular process after the microstructure in master mold can be easily made with the LIGA and MEMS technology. Before embossing, the plastic plates must be heated above glass transition temperature. The heating is usually done with hot plates. It is time-consuming, and the core of the plates is unnecessarily softened. This study attempts to use the Ultrasonic vibration as heat generator in hot embossing. The method has been used in conventional ultrasonic welding. This paper has two objectives: (1) To measure the temperature distribution and evolution at different depth of the ultrasonic-heated plastic plates, with comparison to those heated with hot plate; (2) To study the microstructure replication capacity of the ultrasonic-heating embossing of amorphous and semi-crystalline plastic plates. Temperature measurement reveals that Ultrasonic heating provides very rapid heating of surface layer. For the system used (15kHz,28μm amplitude),the temperature reached and the time taken to reach such temperature depends on the vibration time. For the same peak temperature, Ultrasonic heating takes less than 10 seconds, while conventional hot-plate heating takes more than 120 seconds. The cooling is also faster in the plastic plates heated with ultrasound than those heated with hot plates. It is proven to be an effective heating/cooling system for hot embossing operation. The replication capacity of microstructures using ultrasonic heating is not as good as those using hot plates. But it may be due to the other processing such as pressure and vibration amplitude etc. The operation windows, defined as the range of processing on the plane of vibration time and holding pressure, for amorphous plastics are much large than those for semi-crystalline ones.

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33

Li, Meng-Ke y 李孟科. "Infrared Radiation Heated Hot Embossing of Plastic Plates with Micro-features". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/39557219617554689360.

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碩士
長庚大學
機械工程研究所
95
This paper reports a rapid fabrication of polymeric micro-block arrays using an IR heated hot embossing process. A pneumatically actuated embossing facility with IR heating capacity has been designed, constructed and tested in our laboratory. To mold micro-blocks onto the plastic plates, a silicon mold with an array of micro-block cavities is fabricated by photolithography and deep reactive ion etching. During the embossing process, a PMMA plate was first placed above the mold. A ceramic IR heater was placed above the PMMA plate to heat the mold. During heating, the IR passed through the transparent PMMA to reach and heat up the mold surface. After the retrieve of the IR heater, the pneumatically actuated embossing facility pressed the plastic plate against the hot master mold. A micro-block array is obtained. The effect of various processing parameters on the replicability of the micro-blocks was investigated. Under the proper processing conditions, the 50x37 arrays of polymeric micro-blocks, with a dimension of 200 m x 80 m x 40m can be successfully fabricated. The experimental results in this study suggest that IR heated embossing could provide an effective way of fabricating microstructures onto plastic plates. This would provide significant advantages in terms of a shorter cycle time as well as improved product quality.

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34

Dung, Yu-Tsai y 董毓才. "Ultrasonic Vibration Hot Embossing of Micro-Structured Parts：Effect of Processing Parameter". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/01652053787293522114.

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碩士
長庚大學
機械工程研究所
92
Hot embossing achieves excellent performance in replicating precise micro-features onto large plastic plates. It has become a popular approach because microstructures in master molds can now be easily made using LIGA and MEMS technologies. However, there are still some problems that confound the overall success of this technology. Long cycle time caused by the conventional electric heatig or hot oil heating is one of them. Before embossing, the plastic plates must be heated to above the glass transition temperature. The heating is usually done with hot plates. It is a time-consuming, and the cores of the plates are unnecessarily softened. This study attempted to use ultrasonic vibration as a heat generator for hot embossing. This heating method has been widely used in ultrasonic welding.This study had two objectives: (1) to study the microstructure replication capacity of ultrasonic-heating embossing of amorphous and semi-crystalline plastic plate; (2) to study the effects of various ultrasonic vibration parameters on the contour of micro-structure, and (3) to identify the relative significance of all these parameters on molded part quality. The experimental results in this study suggested that ultrasonic vibrated hot embossing can provide an effective way of molding microstructures onto polymeric parts. This will provide significant advantages in terms of a shorter cycle time and an improved product quality.

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35

Wang, Ying-Chieh y 王盈傑. "Development of a Micro–Hot Embossing Mold with High Replication Fidelity". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/89039351472794697162.

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碩士
明志科技大學
機械工程系機械與機電工程碩士班
102
In this study the Rapid Tooling (RT) technology is used to fabricate the mold for making Fresnel lens. However, the release agent must be used during the fabrication process, leading to the reduction of the replication fidelity and surface finish of epoxy resin mold. Therefore, for enhancing transcription rate and improving surface roughness, the low pressure plasma system is used in this study for surface modification of silicone such that the use of release agent can be avoided during RT process to develop the micro RT fabrication technology. 　　The results of this study indicate that, by using surface modification and rapid tooling for fabricating the hot embossing mold for Fresnel lens. The total depth and width transcription rates of epoxy resin mold fabricated by the integration of surface engineering are around 97.9 % and 97.7 %, which are improved by 1.2 % and 0.6% from the 96.7 % and 97.1 % of the total depth and width transcription rates of traditional epoxy resin. The use of optimal parameters of surface modification for testing will lead to a surface roughness of epoxy resin at 47.5 nm and a surface roughness improvement rate of 39.4 %.The oxygen atom radicals reacting with the surface of silicone will lead to oxidation at the material surface and the change of structure, and the silicone contact angle after oxygen plasma treatment is 87°. As a result, the advantages of micro-rapid tooling mold proposed in this study include simple fabrication method, reduced surface roughness, and enhanced transcription rate.

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36

Chang, Jer-Haur y 張哲豪. "Development of Fluid-Based Heatingand Pressing Systems for Micro Hot Embossing". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/54253211045394024426.

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博士
國立臺灣大學
機械工程學研究所
92
This thesis is devoted to the development new system and process for large-area hot embossing. First, a series of hot embossing experiments were conducted to transcript the micro U-groove features in a stamper onto large thin thermoplastic films with traditional hot press. Film embossing is found different from plate embossing in applying slight pressure during heating and backing the stamps with cushion pads. The formability of amorphous PC films was found to be much larger than that of the semi-crystalline PET films. During conventional hot embossing, the substrate and the stamp are brought into contact and are compressed directly by the hot plates of the machine. The accuracy and area of replication are limited due to the inherent non-uniform pressure distribution. Si-wafers are too brittle to be used as embossing tools with the conventional hot embossing operation. In this study, three innovative methods of rapid heating and uniform pressing for micro hot embossing were developed. Fluids were used as heating and pressing media. With these three systems, the temperature of substrate rises rapidly and uniform pressure is exerted over the whole substrate. The working fluids used in this experiment included steam, gas, and oil. In addition, rapid heating through far infrared radiation (FIR) was also implemented with a gas pressurized hot embossing process. It was found that a 0.2 millimeter-thick PVC substrate can be heated from 25oC to 130oC in 30 seconds using steam heating, in only 25 seconds using FIR heating, and in 3.5 minutes using oil heating. The heating speeds of all three methods are much faster than those using conventional hot-plate heating, which takes more than 10 minutes. Successful replications of micro-features onto 4-inch and 12-inch substrates have been achieved. The simulations of heat transfer in these new processes are also carried out with finite element software of ANSYS. Heat transfer analysis proves helpful in predicting temperature response and in the design of process.

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37

Lin, Cheng-Wei y 林政緯. "Development of Micro/Nano-Structures on Optical Glass by Roller Hot Embossing". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/32434304980255533993.

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碩士
國立臺灣大學
機械工程學研究所
100
Glass substrate with micro/nano structures on the surface have many applications and become popular recently. There are many properties such as hydrophobicity and anti-reflection associated with glasses with micro/nano structures on the surface. Traditional fabrication method such as laser machining, wet/dry etching are time consuming and expensive. Replica molding methods can fabricate surface micro/nano stuctures with fast speed. Among them, micro hot embossing is the most commonly used method. However, the long heating/cooling cycle and the batch-mode production prevent it from being used in mass production. In this research, a novel roller imprinting method is proposed to fabricate micro/nano structures on the surface of glass substrates. During the roller imprinting process, heating and cooling were preformed separately and the fabrication of micro/nano structures were carried out continuously. In this research, a roller imprinting facility, with induction and infrared heaters, is designed and implemented to fabricate micro/nano structures on the surface of glass substrates. Methods to increase transcription rate was investigated in this research. Nano pillars are fabricated on the surface of soda-lime glass substrate with the mold of anodic aluminum oxide. The optical performance of anti-reflection are measured. Reflection rate was reduced from 8~25% to 0.8~2.5% in the range of wavelength between 300~800 nm. It proved that glass substrate with nano pillars on the surface have anti-reflective effect. Finally, by intergrated procedure; both micro and nano structures were fabricated on the surface of soda-lime glass and hybrid micro/nano structures were fabricated successfully. The contact angle of the surface with micro/nano structures was 114°, much higher than 20° in bare glass. This study demonstrated the potential of fabricating micro/nano structures using roller hot embossing.

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38

Lai, Mei-Chun y 賴美君. "Micro- and nano- structures formation on cycloolefin copolymer through hot embossing imprint". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/hbvsm8.

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碩士
國立臺北科技大學
有機高分子研究所
96
The research investigates the flow properties of cycloolefins copolymer(COC) substrate in the cavity with nano-and micro- structure by hot embossing imprint. There are two COC materials with similar glass transition temperatures (Tgs) and different melting mobility used in the research . The nano-cavity of a template with pillar pattern is 200nm diameter and the micro-cavity with prism pattern has a width of 50nm and a height of 25um .The filling heights and shapes are studied by different imprint conditions such as imprint temperature ,imprint force and imprint time. The theories of viscoelastic fluid are applied to study the filling height of polymer substrate in nano-and micro-cavity. The result of nano-cavity show that when the imprint temperature is 30℃ hiegher than Tg , the mobility of two mCOC resins increase substantially. The filling heights of mCOC-1 are different with different imprint temperatures and imprint forces. However, the filling heights of mCOC-2 are little influenced by the imprinting forces when the imprint temperatures are heigh. The capillary theory are derived for the filling heights of mCOC-1 and mCOC-2 at the imprinting time 1 minutes in nano cavity. The results of micro-structure indicate that when the imprint temperature are 15℃~20℃ higher than Tgs of mCOC resins , imprinting temperature is the key factor to determine the imprinting force and imprinting time.

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39

許旭昌. "The Simulation of Temperature and Stress on the Micro Hot-Embossing Process". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/42905264226372993131.

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40

Khuntontong, Puttachat [Verfasser]. "Fabrication of polymer micro devices by ultrasonic hot embossing / vorgelegt von Puttachat Khuntontong". 2008. http://d-nb.info/991283651/34.

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41

Chen, Po-Lin y 陳柏霖. "Development of Micro/Nano Hybrid Structures on Optical Glass by Roller Hot Embossing". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/20721950709874584400.

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碩士
國立臺灣大學
機械工程學研究所
101
Glass is the preferred material for quality optical devices due to its high refractive index and low color aberration. Glass also possesses high mechanical strength and chemical resistance. Surface sub-wavelength nanostructures are known as antireflective and water repellent structures. By fabricating these sub-wavelength nanostructures on surface of micro optical components made of glass, premium optical device with low surface reflection and self-cleaning properties can be realized. As the demand of fabricating micro/nano structures on glass, the need for low-cost, simple and fast fabrication method has increased. Currently, most micro or nano structures on glass are manufactured by direct-machining such as e-beam lithography and laser machining techniques which are expensive and time-consuming. Mold replicating process such as micro/nano hot embossing has disadvantages of discontinuous process and long cycle time. In this research, for continuous and fast production, hot rolling method is developed. There are three major parts in this research. In the first part, a novel method was invented by combining embossing and anodic aluminum oxide method to create AAO mold with hybrid micro/nano structures to fabricate quality microlens arrays on optical glass with low surface reflection by hot rolling. Nano pillar arrays on the surface of microlens can reduce surface reflection from 7.60% to 0.54% at 550 nm wavelength. The overall nano/micro hybrid microlens can increase contact angle from 67.15∘ to 120.70∘. In the second part, eletro-formed nickel mold was used to prevent mold sticking and enhance rolling performance. The AAO mold was replicated by gas-assisted hot embossing followed by electroforming to reduce cycle time. In the last part, nano pillars array was hot rolled on Gorilla tempered glass by using anodic aluminum oxide mold to reduce surface reflection of glass and to increase self-cleaning ability. Nano pillars array on Gorilla glass can reduce up to 90% of broadband surface reflection. Meanwhile, the contact angle increased from 39.20∘ to 88.75∘. By combining the glass with Fresnel lens microstructure, this composite optical component can increase up to three time of energy efficiency on solar panels.

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42

Chang, Chih-Sheng y 張志聖. "A study of fast hot embossing processes for micro and nano structure fabrication". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/89212827375138131669.

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碩士
國立臺灣科技大學
機械工程系
98
Hot embossing is one of the micro/nano imprint techniques and an alternative candidate for the next generation patterning technology. However, the process needs a long cycle from heating, pressing to cooling. It has to be improved in order to become an efficient mass-production method. In this study, we applied a synchronous method with a special designed mold to reduce the cycle time of hot embossing process. In our experiment hot embossing process was split into three parts. Which are heating, imprinting and cooling. These three parts were able to be synchronous and therefore the cycle time of hot embossing was reduced. The synchronous method was successfully to replicate microstructure and nanostructure with high transfer rate. Furthermore, a study of anti-adhesive layer by atmospheric plasma was carried out. Operating parameter, temperature effect, durability and lifetime were evaluated by measuring the variation of contact angle in different experimental conditions. The establishment of a new technology applied on ant-adhesive process of mold. It will be used in fast hot embossing processes.

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43

Tsai, Tsan-Hung y 蔡璨鴻. "A study of hot embossing process on polylactic acid polymer micro/nano structure fabrication". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/33915040135751735327.

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碩士
國立臺灣科技大學
機械工程系
100
Polylactide (PLA) is a widely used polymer for biomedical devices which has received much attention because of its originating from renewable resources and its potential biodegradability. The primary objective of this study was to measure the material and forming properties of PLA at hot embossing process. The properties of the PLA material have been investigated with different imprint temperature and imprint time by micro hardness tester, material test machine, gel permeation chromatograph (GPC), differential scanning calorimeter (DSC) and X-ray diffraction (XRD). As the results shown, if the imprint temperature or imprint time increases more, the mechanical properties may change significantly. The results show that this phenomenon mainly occurs due to the crystallization. However, the results show that if we control the imprint temperature between 70oC to 110 oC, imprint time within 3 minute, a good elongation at break will be obtained. In addition, the forming characters of PLA micro/nano structure with nanoimprint technology are studied by Taguchi method. According to experimental results the transfer rate has been improved from 79.9% to 96.3% with process parameters of demolding temperature 40oC, imprint temperature 110oC, imprint pressure 9MPa and imprint time 60s. The results show that this process can reduce the experiment and manufacturing time. This study will contribute to the biomedical devices fabrication with biodegradable polymers by hot embossing process.

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44

Chang, Huang-Chang y 張煌昌. "A study of fabrication micro convex spherical structure in amorphous resin through hot embossing". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/86557870781566098652.

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碩士
國立中央大學
機械工程研究所碩士在職專班
95
The common MEMS processed technology often limits to deposits, lithography etching, laser processing, LIGA etc, So the production cost is expensive. This experiment uses the micro EDM technology, manufacture mold with radius 0.05mm depth 0.02mm micro concave spherical, using the hot embossing machine formation, and processed has material amorphous resin ABS, PMMA, PC, the grain weight approximately is 0.01g~0.016g, then for micro convex spherical structure use hot embossing formation. In recent years the optics industry including: digital camera, traditional camera, photographic equipment, optics part, lens, back light mold, and LCD optics of concave convex, almost uses PMMA, PC transparent material. ABS is auxiliary and matches the resin to mix the compound material. Therefore this experiment by ABS, PMMA and PC three kind of plastic materials discusses the formation’s the temperature, the pressure, and time etc, to forming influence the precision. According to the hot embossing experimental results show that, ABS, PMMA, and PC etc, was high precision material to form , with besides the above parameters, control the cooling temperature , and the micro concave spherical mold quality selects, and grinding polished the system the improvement etc, to product of the micro convex spherical structure, was important influence parameter. The experimental result demonstration suitable processing parameter combination, roughness of the microstructure spherical may reach Ra 0.030μm , its micro shape diameter was approximately 50μm spherical , completes conforms with the general manufacture light guide board of the optics plant request. Although the experimentation method was simple, but its micro shape spherical precision forming was good for industry technology development.

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45

Lin, Yi-Kai y 林倚楷. "Optimization of Applying UV-Curing Plate-to-Plate Roller Embossing on Micro-Channels Fabrication". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/hx642j.

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碩士
國立高雄應用科技大學
模具工程系
103
It includes three parts in improving UV-curing plate-to-plate roller embossing machine. The first part is to better the pressure controlling system by using pneumatic cylinder instead of micrometer caliper to control the pressure. By doing so, it can make the pressure get a more accurate control and make the machine work more stably. The second part is to improve lightproof components. The improvement can precisely control the size of UV light exposure with different UV glues. Thus, UV glue can be solidified accurately after rolling. The third part is to use aluminum-made roller. Therefore, after saving weight, we can enlarge the size of roller. It can let the UV-curing plate-to-plate roller embossing system to be applied to wider areas, to achieve the best value for economic benefit and to make it competitive in the future. Our experiment "UV-Curing Plate-to-Plate Roller Embossing" achieved parameter optimization by using Taguchi’s Method to find out the optimal parameter. We find out the optimal parameter to make the duplication and uniformity of the structure better. It utilizes two micro-channel structures with different shape and different depth to width ratio to make the micro-channel. First, we use UV-curing plate-to-plate roller embossing machine to make the micro-channel. Then we employ PDMS to roll over the micro-channel. After that, we compare the manufacturing process and the depth with the convexity structured micro-channel. Finally, we investigate into the advantages and disadvantages of the two different procedures. The method can replace the current hot compacting prototyping and injection prototyping to make production and develop a different and rapid procedure. At last but not the least, we develop the mixture flow testing of the micro-channel with different-colored food coloring.

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46

李和政. "The study of embossing for the fabrication of micro channel on the glass surface". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/03216428921310652767.

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碩士
中華大學
機械工程學系碩士班
96
Abstract Glass based micro-fluidic chip has many advantages such as chemical stability, benefit to fluorescence analysis and better biocompatibility which have great potential for biomedical application. Currently, it is still not satisfactory for producing the micro-channel on the glass surface by traditional wet or dry etching process. This study aims to fabricate the micro-channel on the glass surface by using the technique of hot embossing. The WC/Co micro-needle was joined on the WC/Co plate as the convex micro-mold. The effects of embossing temperature and pressure on the surface profile and qualities of micro-channels were investigated. It shows that the optimum hot embossing condition for borosilicate glass materials are at a pressing temperature of 660℃ and under a load of 80kg/cm2. At this condition the surface profile of the micro-mold can be replicated to the glass surface effectively. Due to the increase of glass flow resistance, cracks were appeared on the glass surface when the embossing temperature was lower than 660℃. The increase of the embossing temperature favors glass flow and micro-channel formation, but it may result in the glass sticking on the micro-channel surface and influence the glass transparency. A higher pressure is benefit to the replication of micro-channel structure on the glass surface. However, a slow pressing speed is required to prevent cracks on the surface of micro-channel. Keyword: hot embossing、micro channel、viscosity.

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47

Chen, Chin Lung y 陳進龍. "A study on silicon mold Insert fabrication and micro hot embossing of polymer splitter". Thesis, 2003. http://ndltd.ncl.edu.tw/handle/30909393520637916066.

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碩士
國立交通大學
精密與自動化工程學程碩士班
91
This research focuses on the manufacturing of multimode polymer splitter. MEMS fabricating process was first adopted for the fabrication of four inches silicon mold insert and then the micro hot embossing technique was applied on optical class PMMA material to make splitters. Complete thesis is divided into two topics, which include silicon mold insert fabrication and micro hot embossing process. In the design of optimal silicon mold insert mask the BeamPROP software was used. Investigations were then focused on Lithography and non-isotropic etching process, as well as micro channel’s geometry and anti-adhesive thin films treatment on the surface of mold insert. In the topic of micro hot embossing analysis, the factorial experiment and Taguchi method were used to find the most significant control factor and the optimal combination of micro hot embossing parameters. The geometry characteristics and micro defects that can affect the performance of the finished products were also discussed. The above study concluded, 1.Silicon mold insert fabricated by using positive resistance etching stop layer is most suitable, while ICP-RIE is not suitable for mold insert with large area because of the non- uniformity of depth control. 2.The most significant control parameter in the micro hot embossing process is de-molding temperature, followed by the embossing temperature. The optimal combination of process parameters are embossing temperature of 120℃, embossing forces of 32,500N, embossing time of 270sec and de-molding temperature of 70℃。

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48

Sood, Varun. "An experimental study on thermal bonding effects of PMMA based micro-devices using hot embossing". 2007. http://hdl.handle.net/10106/899.

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49

HAO, HUXU XUAN y 許軒豪. "A simple and low cost method to fabricate micro-featured mold for polymer hot embossing". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/84g6jg.

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碩士
國立高雄應用科技大學
模具工程系
105
With the progress of science and technology and the demand for intelligent life, all kinds of light and wear-type optoelectronic products and medical equipment has been gradually commercialization and vigorous development. In addition, polymer microstructure components in these advanced technology products often play a very important role that can effectively provide a variety of mechanical properties and photoelectric functions. Nowadays, many fabrication methods for micro-featured mold have been proposed and developed, such as the high-energy beam processing, ultra-precision machining, silicon-based micro-machining and LIGA-like technology. Then, the polymer replication technology was used to mass production of polymer microstructure components. However, most of the fabrication techniques for micro-featured molds are complex, time consuming and require expensive equipment. To solve these problems, we present an effective and low cost method for the fabrication of various micro-featured molds for the replication of polymer microstructure components. The method involves a small metal wire winding technology and polymer hot embossing process. A micro-featured mold is directly fabricated by small metal wire winding assembly on the surface of metal plate. Then, the metal plate with small metal wire winding pattern can then be used as a mold for the replication of a microstructure component through polymer hot embossing process. Therefore, the objective of the work described here was to demonstrate a low-cost and non-photolithographic method for the fabrication of micro-featured mold with array patterns, to be used for the replication of polymer microstructure components. In this study, the effects of polymer hot embossing processing conditions on the shape and dimension of fabricated micro-pattern on PMMA sheets were investigated. The replicated quality and optical properties of the produced polymer microstructure components were measured and analyzed. Finally, to optimize the quality of polymer microstructure components, the Taguchi experimental method was conducted. The optimized factor levels has been calculated and found.

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50

Yu, Che-Hao y 游哲豪. "Development of Ultrasonic Assisted Micro-hot embossing Process for Rapid Fabrication of Plastic Microlens array". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/80094907909449964013.

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碩士
國立高雄應用科技大學
模具工程系碩士班
102
In recent years, plastic microlens array device has been widely used in various applications such as optical fiber communication, micro-projector system, optical scanner module, LED lighting system and flat panel display. With cost of paramount concern for many new micro-system applications, plastic are becoming one of the most practical materials for mass production. And, micro-injection molding and micro-hot embossing are regarded as the best mass-production methods to fabricate microlens array devices. However, these processes involve high temperature, high pressure and require expensive facilities. They are complicated, time-consμming batch-wise processes. From this perspective, the ultrasonic assisted micro-hot embossing technology for rapid fabricating microlens array devices has been proposed and developed. In this study, the effects of processing conditions on the shape and quality of formed microlens array devices are investigated. Under the proper processing conditions, the perfect plastic microlens array device can be rapidly fabricated.

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