Articoli di riviste: "FILM THICKNESS SIMULATION"

1

Markov, A. B., A. V. Solovyov, E. V. Yakovlev, E. A. Pesterev, V. I. Petrov e M. S. Slobodyan. "Computer simulation of temperature fields in the Cr (film)-Zr (substrate) system during pulsed electron-beam irradiation". Journal of Physics: Conference Series 2064, n. 1 (1 novembre 2021): 012058. http://dx.doi.org/10.1088/1742-6596/2064/1/012058.

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Abstract The paper presents the results of numerical simulation of the distribution of thermal fields during the formation of Cr-Zr surface alloy using a pulsed low-energy high-current electron beam (LEHCEB). The melting thresholds of the Cr-Zr system for different thicknesses of Cr films were calculated. The melting threshold of the Cr-Zr system increases linearly with increasing Cr film thickness. A linear regression dependency model of the melting threshold on the film thickness is proposed. Evaporation thresholds of the Cr-Zr system for different thicknesses of Cr films were calculated. The evaporation threshold of the Cr-Zr system increases linearly with increasing Cr film thickness. A linear regression dependency model of the evaporation threshold on the film thickness is proposed. The value of the LEHCEB energy density at which the lifetime of the film and substrate are equal is calculated. This value is a maximum value for the effective formation of Cr-Zr. A model of the LEHCEB energy density, at which the lifetime of the film and the substrate are equal, in the form of a third-degree polynomial is proposed.

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Grigoriev, Fedor V., Vladimir B. Sulimov e Alexander V. Tikhonravov. "Atomistic Simulation of Stresses in Growing Silicon Dioxide Films". Coatings 10, n. 3 (29 febbraio 2020): 220. http://dx.doi.org/10.3390/coatings10030220.

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Dependence of stress values in silicon dioxide films on its thickness in the initial stage of film growth was investigated using atomistic molecular dynamics simulation. It was shown that the stress in normally deposited films was compressive and varied slightly with growth of film thickness. The stress in the glancing angle deposited films was several times lower than the stress in the normally deposited films, and varied from compressive stress to tensile stress with increasing film thickness. An essential anisotropy of stress tensor components was revealed for the case of glancing angle deposition. The calculated stress values were in the interval of experimental data.

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Du, Run, Anying Zhang, Zhihua Du e Xiaoyu Zhang. "Molecular Dynamics Simulation on Thin-Film Lubrication of a Mixture of Three Alkanes". Materials 13, n. 17 (20 agosto 2020): 3689. http://dx.doi.org/10.3390/ma13173689.

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We used the COMPASS forcefield to perform molecular dynamics (MD) simulation of a mixture composed of three alkanes as the lubricant for the thin-film lubrication. The viscosity of the lubrication film in the non-working state, the final film thickness, and density distribution were investigated. The results reveal that the viscosity error among different initial film thicknesses in the non-working state is within 5%, which confirms the applicability of the model and the forcefield. The viscosity decreases oscillating as temperature increases. Whatever the initial film thickness is, the film thickness change rate with respect to pressure load is almost the same. When pressure increases, the density peaks increase. As the initial film thickness increases, the normalized thicknesses of adsorption and ordered layers decrease. In nanoscale, the density predicted by the MD simulation is higher than the prediction of the Tait equation, even if the adsorption layers is excluded.

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Wang, Ben, Xiuhua Fu, Shigeng Song, Hin Chu, Desmond Gibson, Cheng Li, Yongjing Shi e Zhentao Wu. "Simulation and Optimization of Film Thickness Uniformity in Physical Vapor Deposition". Coatings 8, n. 9 (16 settembre 2018): 325. http://dx.doi.org/10.3390/coatings8090325.

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Optimization of thin film uniformity is an important aspect for large-area coatings, particularly for optical coatings where error tolerances can be of the order of nanometers. Physical vapor deposition is a widely used technique for producing thin films. Applications include anti-reflection coatings, photovoltaics etc. This paper reviews the methods and simulations used for improving thin film uniformity in physical vapor deposition (both evaporation and sputtering), covering characteristic aspects of emission from material sources, projection/mask effects on film thickness distribution, as well as geometric and rotational influences from apparatus configurations. Following the review, a new program for modelling and simulating thin film uniformity for physical vapor deposition was developed using MathCAD. Results from the program were then compared with both known theoretical analytical equations of thickness distribution and experimental data, and found to be in good agreement. A mask for optimizing thin film thickness distribution designed using the program was shown to improve thickness uniformity from ±4% to ±0.56%.

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Yan, Ying, Jiarun Li, Qiuyu Liu e Ping Zhou. "Evaporation Effect on Thickness Distribution for Spin-Coated Films on Rectangular and Circular Substrates". Coatings 11, n. 11 (29 ottobre 2021): 1322. http://dx.doi.org/10.3390/coatings11111322.

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Spin-coating is widely applied in the field of thin-film fabrication due to its simplicity and high film uniformity. To prepare thin films on rectangular substrates by spin-coating, the simulation and experimental methods were used to study the characteristics of the film thickness in this work. The two-phase flow simulations of spin-coating on a rectangular substrate and circular substrate were carried out with the volume of fluid (VOF) method. The simulation results showed that the airflow field and the substrate geometry had little effect on the evolution of spin-coated film thickness. However, in the experimental results, there was a significant difference in the thickness of the spin-coated film on the rectangular substrate and the circular substrate. According to further study, the solvent evaporation that was neglected in the simulation was the dominant factor of the differences. In addition, it was concluded that the non-uniform evaporation caused by the surface tension and edge accumulation in the later spin-coating stage was the main reason for the film accumulation of the windward area on the rectangular substrate. This work is useful to obtain a deeper understanding of the thin-film formation mechanism of spin-coating.

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Wang, Kaijie, Yongzhi Cao, Yaowen Cui, Aiying Ye, Shaofan Yi e Zhenjiang Hu. "Study on Parameter Correlation of Thickness and Performance of Anodizing Film on 6061 Aluminum Alloy Frame in High Energy Laser System". Coatings 12, n. 12 (16 dicembre 2022): 1978. http://dx.doi.org/10.3390/coatings12121978.

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As stray laser light is difficult to avoid in high-energy laser systems, it is of great significance to improve the laser damage resistance of the aluminum alloy frame anodizing film system. In this paper, the effects of anodic oxidation parameters on the thickness and performance of 6061 aluminium alloy anodic oxide composite film systems are investigated combining experiments and simulations. The thickness of the oxide film is calculated theoretically, and the simulation model is established. Then the effects of anodizing parameters and the reasons are analyzed. After characterizing the surface quality and laser damage resistance of the oxide film, the influence of anodizing parameters is summarized. This paper enables advance calculations of film thickness within a certain range, combined with the film properties, to provide a reference for the laboratory preparation of 6061 anodizing films and the preparation of structure-specific composite film systems based on the film.

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P, Ramesh, e James Gunasekaran E. "Numerical Simulation of Film Thickness Formation in a PFI Engine Under Motoring Conditions". Bonfring International Journal of Industrial Engineering and Management Science 9, n. 3 (30 settembre 2019): 11–15. http://dx.doi.org/10.9756/bijiems.9032.

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HU, ZHAN-NING, e V. C. LO. "THICKNESS DEPENDENCE OF THE COERCIVE FIELD IN FERROELECTRIC THIN FILMS". International Journal of Modern Physics B 20, n. 22 (10 settembre 2006): 3223–31. http://dx.doi.org/10.1142/s0217979206035424.

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By considering the effects of the space charges and domain boundaries in ferroelectric thin films, the thickness dependence of coercive field (Ec) is numerically simulated based on the four-state Potts model with the nearest-neighbor interactions between dipole moments. For large thickness, experimental results where Ec decreases with thickness can be produced from our Monte-Carlo simulation. On the other hand, when the thickness is very small, our simulation gets that Ec increases with thickness by the study of the polarization switching in the film. This gives an explanation of the experimental result by Zhu et al. in J. Appl. Phys.83, 1 (1998) for SBT-BTN film, and a similar report by Bune et al. in Nature391, 874 (1998) for the crystalline film. The critical temperature of the thin film is also discussed.

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Khaneft, Alexander V., Vadim A. Dolgachev e Svyatoslav A. Rybin. "The Effect of Metal Film Thickness on Ignition of Organic Explosives with a Laser Pulse". Molecules 24, n. 24 (16 dicembre 2019): 4600. http://dx.doi.org/10.3390/molecules24244600.

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The results of numerical ignition simulation of pentaerythritol tetranitrate (PETN), cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) by aluminium (Al) and molybdenum (Mo) films heated by nanosecond laser pulses in a three-layer system: glass–metal–explosive material (EM) are presented. Influence of metal film thickness on the time of EM ignition delay was considered. A non-linier dependence of time of delay of ignition of EM from thickness of a metal film is shown. The greatest critical thicknesses of Al and Mo metallic films at which ignition of EM is still possible were determined. It was established that the greater the thickness of the metal film and heat resistance of EM, the greater the heat reserve needed in EM ignition film. It was established that the ignition delay time of EM increases in the sequence of PETN, RDX, HMX and TATB.

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Xiong, Min, Chuanxin Teng, Ming Chen, Yu Cheng, Shijie Deng, Fuwang Li, Hongchang Deng, Houquan Liu e Libo Yuan. "Simulation Study of High Sensitivity Fiber SPR Temperature Sensor with Liquid Filling". Sensors 22, n. 15 (30 luglio 2022): 5713. http://dx.doi.org/10.3390/s22155713.

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In this paper, a high sensitivity fiber temperature sensor based on surface plasmon resonance is designed and studied. In the simulation, the single mode fiber is polished to remove most of the cladding, and then gold and silver films are added. Finally, it is embedded in the heat shrinkable tube filled with a thermo-optic coefficient liquid for curing. The numerical simulation results show that the sensing characteristics are sensitive to the remaining cladding thickness of the fiber, the thickness of the gold film and the thickness of the silver film. When the thermo-optic coefficient of the filling liquid is −2.8 × 10−4/°C, the thickness of the gold film, the thickness of the silver film and the thickness of the remaining cladding of the fiber are 30 nm, 20 nm and 1 μm, respectively. The sensitivity of the sensor designed in this paper can reach −6 nm/°C; this result is slightly higher than that of similar research in recent years. It will have a promising application prospect in flexible wearable temperature sensors, smart cities and other fields.

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Chen, Hui, Wei Yu Chen, Yun Fei Chen e Ke Dong Bi. "Out-of-Plane Thermal Conductivity of Silicon Thin Film Doped with Germanium". Advanced Materials Research 1082 (dicembre 2014): 459–62. http://dx.doi.org/10.4028/www.scientific.net/amr.1082.459.

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The out-of-plane thermal conductivity of silicon thin film doped with germanium is calculated by non-equilibrium molecular dynamics simulation using the Stillinger-Weber potential model. The silicon thin film is doped with germanium atoms in a random doping pattern with a doping density of 5% and 50% respectively. The effect of silicon thin film thickness on its thermal conductivity is investigated. The simulated thicknesses of silicon thin film doped with germanium range from 2.2 to 10.9 nm at an average temperature 300K. The simulation results indicate that the out-of-plane thermal conductivity of the silicon thin film doped with germanium decreases linearly with the decreasing film thickness. As for the film thickness of 9.8nm and the average temperature ranging from 250 to 1000 K, the investigation shows that the temperature dependence of the film thermal conductivity is not sensitive.

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Mousa, Hana Mohammed. "Simulation of An Asymmetric TM Metamaterial Waveguide Absorber". JOURNAL OF ADVANCES IN PHYSICS 4, n. 3 (26 giugno 2014): 585–94. http://dx.doi.org/10.24297/jap.v4i3.2013.

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This paper tackles the simulation of an asymmetric Â TM mode absorption Â in a lossy metamaterial (left-handed) slab (LHM) sandwiched between a lossy substrate and coverd by a losseless dielectric cladding. The asymmetry solutions of the eigen value equation describeÂ lossy â€“guided modes with complex â€“valued propagation constants .Â The dispersion relations , normalized field and the longitudinal attenuationÂ were numerically solved for a given set of parameters: frequency range; filmâ€™s thicknesses; and TM mode order. I found out that high order modes which are guided in thinner films are generally have more loss of power than low-order modes since the mode attenuation along z-axis increases to negative values by the mode's order increase and the film thickness decrease . Moreover, Â LHM , atÂ incident wavelength =1.9, refractive index=andÂ at thickness , Â Â guides the power betterÂ thanÂ RHMÂ or metal one. This LHMÂ Â is appropriate for solar cell applications. For arbitrary LHM, at frequency band of wavelengt(600, 700 to 1200 )nm, Â the best absorption is attained at longer wavelengths and for lower order modes at wider films.

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13

Zhou, Qing Xiao, Chao Yang Wang, Zhi Bing Fu e Yong Jian Tang. "Numerical Simulation of Film Thickness Uniformity Deposited by Planar Circular Magnetron Sputtering System". Advanced Materials Research 887-888 (febbraio 2014): 743–48. http://dx.doi.org/10.4028/www.scientific.net/amr.887-888.743.

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There exist angular offset and eccentricity between target and substrate in most practical multi-target magnetron sputtering systems, which should be seriously considered when we calculate the film distribution. This simulation results suggested that excellent thickness uniformity can be obtained when increased the substrate-target distance, angular offset, and eccentricity, but decreased the film thickness simultaneously. However, superior uniformity films without reducing the thickness remarkably can also obtained when the geometry configuration are proper configured.

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Humaidan, Raed M., Ashwaq T. Dahham e Zuheer N. Majeed. "Designed and Simulation of AlGaAs: GaAs Thin Film Solar Cell Using PC1D Program". NeuroQuantology 20, n. 3 (18 maggio 2022): 265–70. http://dx.doi.org/10.14704/nq.2022.20.3.nq22254.

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Obtained the highest competence and finding the best combination of thickness and concentricity of multilayer solar cells is one the most prominent problems in the field of photovoltaic energy. In this research AlGaAs/GaAs solar cell with four layers of window layer, emitter layer, absorber layer and back surface layer. Is modeled in PC1D emulation software. The performance of the solar cell was studied by changeful the thickness and doping concentration of the window layer from the range (0-1)μm, (1015-1020) respectively. Where the best efficiency was 31.2% at thickness and doping 1015cm-3. Where changing the thickness and doping concentricity of the absorber layer from the range (0-5)μm, (1015-1020) respectively. The highest efficiency was 31.4581% at thickness 3.67μm and doping is 1015cm-3. The results of the final solar cell parameters were Isc, Voc, F.F and η has been observed as 31.8mA, 1.109 V, 89.32% and 31.4581% respectively.

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Hu, Y.-Z., H. Wang, Y. Guo e L.-Q. Zheng. "Molecular dynamics simulation of ultra-thin lubricating films". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 212, n. 3 (1 marzo 1998): 165–70. http://dx.doi.org/10.1243/1350650981541976.

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Molecular dynamics simulation has been performed in the present study for a Lennard-Jones (LJ) fluid in Poiseuille flow to examine the Theological behaviour of ultra-thin lubricating films. The results show that as two solid walls continuously approach each other, the effective viscosity of the confined fluid increases and goes towards divergence; the critical pressure of the phase transition declines as the film thickness reduces; when the separation exceeds ten molecular layers, however, the pressure curve slopes gently and tends to an asymptotic value-the bulk transition pressure of the lubricant; and an in-plane ordering structure will develop in the film, which originates from the wall-fluid interface and grows towards the middle of the film as the system pressure increases. It is concluded that the rheological performance of the lubricant may become film thickness dependent and a solid-liquid transition may be induced when the film is molecularly thin.

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Susila, Anggara Budi, Erfan Handoko, Esmar Budi e Agus Setyo Budi. "Influence of thickness on heat treatment from 300 to 1100 K of aluminum thin film". Journal of Physics: Conference Series 2193, n. 1 (1 febbraio 2022): 012028. http://dx.doi.org/10.1088/1742-6596/2193/1/012028.

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Abstract We investigated the influence of Aluminum thin film thickness during heat treatment. The films with thickness of 5 nm, 10 nm and 15 nm were heated from room temperature up to above melting point with same heating rate. Molecular Dynamics (MD) simulation is employed to study the behaviour of the thin film where the atoms were followed based on its trajectories. Thin film thickness gives significance contribution to the mechanism of the melting. Smaller thickness suffered strong pressure oscillation while the thin film temperature is increases. Local crystal structure confirmed the transformation of the system from crystalline state to melting state.

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Maksimova, O. G., A. V. Maksimov e O. S. Baruzdina. "Computer simulation of the structural phase transitions in thin ferroelectric films". Journal of Advanced Dielectrics 07, n. 01 (febbraio 2017): 1750004. http://dx.doi.org/10.1142/s2010135x17500047.

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The influence of free surface and depolarizing field on structural phase transitions in thin ferroelectric films from an ordered state to a disordered one is investigated. The dependences of the order parameter on the distance from the free film surface are calculated. It is shown that with the presence of the depolarizing field and in its absence, the effective thickness of the surface layer depends on the temperature. Nearby the phase transition point, the thickness increases indefinitely. Calculations considering depolarizing field showed that the phase transition points for the bulk ferroelectrics and the film under given boundary conditions coincide. Also shown that in the absence of depolarizing field with mixed boundary conditions, the film thickness does not affect the order parameter, and in presence of the field, this influence is observed.

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Chu, Li-Ming, Jaw-Ren Lin, Hsiang-Chen Hsu e Yuh-Ping Chang. "EFFECTS OF SURFACE FORCES ON SQUEEZE EHL MOTION BETWEEN ELASTIC BALL AND ELASTIC COATED SURFACE". Transactions of the Canadian Society for Mechanical Engineering 40, n. 5 (dicembre 2016): 821–33. http://dx.doi.org/10.1139/tcsme-2016-0067.

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The effects of surface forces (SF) and coated layers (CL) on pure squeeze elastohydrodynamic lubrication (EHL) motion of circular contacts are explored under constant load condition by using the finite difference method (FDM) and the Gauss–Seidel iteration method. The transient pressure profiles, surface force, film shapes, and elastic deformation during the pure squeeze process under various operating conditions in the TFEHL regime are discussed. The simulation results reveal that the difference between SFEHL model and EHL model is apparent as the film thickness is thinner than 5 nm. The oscillation phenomena in pressure and film thickness come mainly from the action of solvation forces. At contact region, the greater elastic modulus and smaller coating thicknesses, the greater pressure distribution, and the smaller film thickness. The film thicknesses are found reverse at outside the contact zone. At the exit region, i.e. the minimum film thickness region, it is valid that the greater the elastic modulus and the smaller the coating thicknesses, the greater the solvation pressure distribution. The effects of surface forces become significant as the film thickness becomes thinner.

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Zhang, Hua Li, Ji Cai Kuai e Fei Hu Zhang. "Modeling of Thickness of the Oxide Film in ELID Grinding". Advanced Materials Research 135 (ottobre 2010): 376–81. http://dx.doi.org/10.4028/www.scientific.net/amr.135.376.

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The properties of oxide films are very important for improving the mass of ELID grinding surface. In this paper, a novel calculation model of thickness of oxide films was proposed; the theoretical calculation and simulation analysis were developed, and were compared with the corresponding experimental results. The results proved that the theoretical calculation and simulation results of the thickness of the oxide films had good agreement with the experimental results. This model could predict precisely the change of thickness of oxide film, the instinct of non-linear electrolysis was explained from a novel aspect of ability of pulsed electrolysis. This model could be used in the on-line control of electrolytic state during practical ELID grinding process.

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Zhang, Qiushu, Bei Peng, Jintao Xu e Mengqi Chu. "Origin of Magnetically Induced Optical Transmission of Magnetic Nanocomposite Films". Polymers 12, n. 11 (29 ottobre 2020): 2533. http://dx.doi.org/10.3390/polym12112533.

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Herein, we present an investigation on the origin of the magnetically induced optical transmission of composite films comprised of polydimethylsiloxane and magnetic nanofillers via experiment and simulation. Structured and unstructured films were used in the study, which were fabricated with and without magnetic fields, respectively. Altered optical transmittance was observed from both types of films when they were subjected to an external magnetic field. Numerical analyses were performed to investigate the effect of the particle movement under magnetic field and the film magnetostriction on the film optical transmittance. The simulation results show that the changed light transmission under magnetic field is mainly due to a variation in the film thickness resulting from the film magnetostriction. The ellipsometric analysis results confirm the altered film thickness in response to the external magnetic field, and the measurements of the film magnetostrictive stresses validate that there is magnetostriction in the magnetic composite films. Additionally, it is indicated that there might be some relationship between the magnetically induced optical transmission and the film magnetostrictive stress under certain conditions.

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Carey, V. P., e A. P. Wemhoff. "Disjoining Pressure Effects in Ultra-Thin Liquid Films in Micropassages—Comparison of Thermodynamic Theory With Predictions of Molecular Dynamics Simulations". Journal of Heat Transfer 128, n. 12 (1 marzo 2006): 1276–84. http://dx.doi.org/10.1115/1.2349504.

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The concept of disjoining pressure, developed from thermodynamic and hydrodynamic analysis, has been widely used as a means of modeling the liquid-solid molecular force interactions in an ultra-thin liquid film on a solid surface. In particular, this approach has been extensively used in models of thin film transport in passages in micro evaporators and micro heat pipes. In this investigation, hybrid μPT molecular dynamics (MD) simulations were used to predict the pressure field and film thermophysics for an argon film on a metal surface. The results of the simulations are compared with predictions of the classic thermodynamic disjoining pressure model and the Born-Green-Yvon (BGY) equation. The thermodynamic model provides only a prediction of the relation between vapor pressure and film thickness for a specified temperature. The MD simulations provide a detailed prediction of the density and pressure variation in the liquid film, as well as a prediction of the variation of the equilibrium vapor pressure variation with temperature and film thickness. Comparisons indicate that the predicted variations of vapor pressure with thickness for the three models are in close agreement. In addition, the density profile layering predicted by the MD simulations is in qualitative agreement with BGY results, however the exact density profile is dependent upon simulation parameters. Furthermore, the disjoining pressure effect predicted by MD simulations is strongly influenced by the allowable propagation time of injected molecules through the vapor region in the simulation domain. A modified thermodynamic model is developed that suggests that presence of a wall-affected layer tends to enhance the reduction of the equilibrium vapor pressure. However, the MD simulation results imply that presence of a wall layer has little effect on the vapor pressure. Implications of the MD simulation predictions for thin film transport in micro evaporators and heat pipes are also discussed.

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Guangxiang, Jin, Li Jianlin, Xu Li e Wu Ziqin. "Monte-Carlo simulation of intensity ratio Is/Ic from substrate and film to determine the film thickness". Proceedings, annual meeting, Electron Microscopy Society of America 46 (1988): 972–73. http://dx.doi.org/10.1017/s0424820100106922.

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The methods of thickness of film on substrate by electron probe have been published in literatures. It may be carried out simply by constructing a calibration curve from x-ray intensity measurments made on a series of films with known thickness on substrate.Sweeney et al. obtained a calibration curve based on a calcula- tied x-ray Ø(p z). As the calculation of Ø(p z) is difficult, Cockett and Davis, proposed using the experimental Ø(p z) of Castaing and Descamps. Bishop and Poole utilised Ø(p z) established by Monte-Carlo calculation for calibration curve.Huchings' method took into account the different electron scattering and absorption in the film on substrate and the bulk standard.Reuter et al., constructing a curve of Ic/Ib (Ic, intensity of the film on substrate; Ib, intensity of bulk standard) versus electron accelerating voltage E, exterpolate the curve so that Ic/Ib equals to 1, the excited x-ray depth obtained is just equal to the thickness of the film. The thickness of the film can be obtained by the use of an appropiate equation of excited x-ray depth.

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Wu, Ping Ping, e Bing Rui Xing. "Phase Field Simulation on the Surface Morphology of Cu/Ti Nano Thin Film". Materials Science Forum 1035 (22 giugno 2021): 712–17. http://dx.doi.org/10.4028/www.scientific.net/msf.1035.712.

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Cu/Ti binary thin film system has many applications for micro-/nano- electro mechanical systems (MEMS/NEMS), micro-electronics and optoelectronics. In nanoscale, the quality and many physical properties of nano thin films are strongly depended on its surface morphology. In the present paper the development of surface morphology of double layered Cu/Ti thin film heterostructure with different composition and thickness has been studied by using the phase field method. The developed method is based on solving Cahn-Hilliard equations of multi-order parameters with considering the interfacial energy and elastic energy. The simulation results show that the thickness of Ti layer and Cu layer in the double-layer thin film structure can affect the surface roughness. For the heterostructures with the Cu layer thickness was fixed at 20 nm, the surface roughness was found to vary from 0.608 nm to 0.712 nm, when the Ti layer thickness increased from 10 nm to 30 nm. The calculated surface morphology and roughness was similar to the experimentally measured values. It is believed that this simulation method is useful in designing multi-layered thin film structure for practical applications.

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Wang, Jin Xin, Ya Ping Han, Xue Lian Gao, Ming Hai Luo e Shao Ze Wang. "Simulation and Experimental of Magnetron Sputtering Film Thickness Distribution". Advanced Materials Research 399-401 (novembre 2011): 1741–45. http://dx.doi.org/10.4028/www.scientific.net/amr.399-401.1741.

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A physical model of magnetron sputtering process was built, the distribution of film thickness on the substrate was deduced, and the data were analysised by using the Mathematica and Matlab. The results show that the distribution of the film thickness on the substrate is uneven and it is also influenced by the radius as well as the distance between the target and substrate. The results of experiment correspond fairly well with the theory. The relational expression provides a theoretical basis for evaluation and estimation of the film thickness.

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Han, Ya Ping, Jing Yan Feng, Qiang Fu, Fan Da Zeng e Guan Wang. "Experimental and Simulation Study of Magnetron Sputtering MgO Film Thickness Distribution". Advanced Materials Research 900 (febbraio 2014): 401–4. http://dx.doi.org/10.4028/www.scientific.net/amr.900.401.

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A physical model of magnetron sputtering process was built, the distribution of MgO film thickness on the substrate was deduced, and the data were analyzed by using the Matlab. nanosized MgO thin film was prepared on Si substrate by magnetron sputtering. SGC-10 was used to measure the thickness of MgO thin film. The results of experiment correspond fairly well with the theory. Both experiment and the theory show that the distribution of the film thickness on the substrate is uneven and it is also influenced by the radius as well as the distance between the target and substrate. The physical model provides a theoretical basis for evaluation and estimation of the film thickness.

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Yang, Mengyuan, e Jingfu Wang. "Numerical simulation analysis of rotary cup centrifugal blast furnace slag". MATEC Web of Conferences 355 (2022): 02011. http://dx.doi.org/10.1051/matecconf/202235502011.

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In the process of centrifugal dry granulation of blast furnace slag, the thickness of the liquid film at the outlet of the rotor will have a significant impact on the degree of crushing of the slag after leaving the rotor and the size of the solid particles formed. Therefore, this paper uses the VOF method to analyse the flow of molten slag inside the cup. The results have shown that the slag flow has a significant effect on the thickness of the liquid film and the linear relationship is obvious; the thickness of the liquid film decreases with the increase of the diameter of the rotary cup and the rotation speed, and the negative correlation with the diameter of the cup is more obvious; Secondly, as the depth of the cup increases, the thickness of the liquid film decreases first and then increases. The inclination angle of the cup wall has little effect on the thickness of the liquid film.

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Patrykiejew, A., e S. Sokolowski. "On the Melting and Disordering of Thin Epitaxial Films". Adsorption Science & Technology 25, n. 7 (settembre 2007): 451–61. http://dx.doi.org/10.1260/0263-6174.25.7.451.

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The disordering of thin films formed on the (100) plane of the face centred cubic (fcc) crystal was studied by the Monte Carlo simulation method. It was shown that the adsorbed films, which order into the (1 × 1) structure in each layer at low temperatures, disorder in a layer-by-layer mode, at least for films with thicknesses of up to 12 layers. It was also demonstrated that, with increasing film thickness, the temperature at which the film disorders depended on the strain resulting from the mismatch between the sizes of the adsorbate atoms and the surface lattice.

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28

Huang, Jen Ching, Fu Jen Cheng e Chun Song Yang. "The Study on Young's Modulus of Multilayered Cu/Ni Multilayered Nano Thin Films by Molecular Dynamics Simulation". Applied Mechanics and Materials 513-517 (febbraio 2014): 113–16. http://dx.doi.org/10.4028/www.scientific.net/amm.513-517.113.

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The Youngs modulus of multilayered nanothin films is an important property. This paper focused to investigate the Youngs Modulus of Multilayered Ni/Cu Multilayered nanoThin Films under different condition by Molecular Dynamics Simulation. The NVT ensemble and COMPASS potential function were employed in the simulation. The multilayered nanothin film contained the Ni and Cu thin films in sequence. From simulation results, it is found that the Youngs modulus of Cu/Ni multilayered nanothin film is different at different lattice orientations, temperatures and strain rate. After experiments, it can be found that the Youngs modulus of multilayered nanothin film in the plane (100) is highest. As thickness of the thin film and system temperature rises, Youngs modulus of multilayered nanothin film is reduced instead. And, the strain rate increases, the Youngs modulus of Cu/Ni multilayered nanothin film will also increase.

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29

Palermo, Mattia Felice, Luca Muccioli e Claudio Zannoni. "Molecular organization in freely suspended nano-thick 8CB smectic films. An atomistic simulation". Physical Chemistry Chemical Physics 17, n. 39 (2015): 26149–59. http://dx.doi.org/10.1039/c5cp04213e.

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30

Fan, Jiang Wei, Qin Lei Sun e Mei Quan Liu. "Improved Optical Model for SiO₂/Si Ultra-Thin Film Thickness Determination by Spectroscopic Ellipsometry". Advanced Materials Research 915-916 (aprile 2014): 803–7. http://dx.doi.org/10.4028/www.scientific.net/amr.915-916.803.

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Different optical models were adopted to fit theoretical simulation curves of a SiO2 ultra-thin film with a density of 2.2 g/cm3 and a thickness of 6nm grown on Si wafer. The results indicate that thickness obtained from fitting decrease linearly with increase of film density. An improved optical model (density of thin film of 2.4g/cm3, roughness of surface of 0.4nm, roughness of surface of 0.3nm) was obtained according to the above analysis and the GIXRR results of our previous work. The improved model could give more accurate thickness value of ultrathin film with thickness less than 10nm. It was employed in the thickness fitting for thermal oxidized SiO2/Si thin film with nominal thicknesses of 2, 4, 6, 8 and 10nm. The results were 2.61, 4.07, 6.02, 7.41 and 9.43nm, decreased by 13.8%10.3%8.1%7.3% and 6.6%, respectively, compared with the results calculated from the traditional model.

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31

Yanbei, Yang, Tian Chunhui e Liu Shuang. "Research on Properties of X-Ray Detection Film Based on Thallium Doped Cesium Iodide". E3S Web of Conferences 252 (2021): 02072. http://dx.doi.org/10.1051/e3sconf/202125202072.

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As X-ray detection imaging has a wide range of applications in medicine, industry, public safety, etc., it is of great significance to study its imaging mechanism and improve its imaging performance. Based on the process of X-ray luminescence in the scintillator material, this paper established a simulation model using a microcrystalline column structure to investigate the relationship between the thickness of the detection film and the light conversion efficiency. With the help of the simulation tool MATLAB, the Monte Carlo method was used to simulate the light conversion process of X-ray in the film, and the results were obtained as follows. Under the condition of other parameters unchanged, the luminous efficiency reached the peak value with the increase of the film thickness, and then gradually decreased with the increase of film thickness. The reason why the conversion efficiency in the early stage increases with the increase of the film thickness is that the film is in a saturated state, and increasing the thickness can cause more X-ray particles to be converted. As the film thickness increases, more fluorescent photons are absorbed as they propagate in the film, resulting in a gradual decrease in conversion efficiency. Therefore, an appropriate film thickness can be selected based on the simulation results to obtain the ideal light conversion efficiency.

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32

Zhang, Jian Jun, Cheng Long Liu e Feng Guo. "Numerical Simulation on Variable Load EHL Problems with Single Asperities". Key Engineering Materials 642 (aprile 2015): 89–93. http://dx.doi.org/10.4028/www.scientific.net/kem.642.89.

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A model of the problem of variable load line contact EHL with single asperities is established. The influences of the single asperities and variable load on the pressure and film thickness are investigated. Numerical results reveal that the existence of single asperities can lead to pressure change drastically and film thickness become thin in the vicinity of asperities. The effects of the variable load on the pressure and film thickness are discussed. The comparison of the variable load and steady load is given.

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33

Zhang, Xing Li, Zhao Wei Sun e Guo Qiang Wu. "Molecular Dynamics Simulation on the Out-of Plane Thermal Conductivity of Single-Crystal Carbon Thin Films". Advanced Materials Research 60-61 (gennaio 2009): 430–34. http://dx.doi.org/10.4028/www.scientific.net/amr.60-61.430.

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In this article, we select corresponding Tersoff potential energy to build potential energy model and investigate the thermal conductivities of single-crystal carbon thin-film. The equilibrium molecular dynamics (EMD) method is used to calculate the nanometer thin film thermal conductivity of diamond crystal at crystal direction (001), and the non-equilibrium molecular dynamics (NEMD) is used to calculate the nanometer thin film thermal conductivity of diamond crystal at crystal direction (111). The results of calculations demonstrate that the nanometer thin film thermal conductivity of diamond crystal is remarkably lower than the corresponding bulk experimental data and increase with increasing the film thickness, and the nanometer thin film thermal conductivity of diamond crystal relates to film thickness linearly in the simulative range. The nanometer thin film thermal conductivity also demonstrates certain regularity with the change of temperature. This work shows that molecular dynamics, applied under the correct conditions, is a viable tool for calculating the thermal conductivity of nanometer thin films.

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34

Chen, Jiayao, Jing Li, Lirong Xu, Wei Hong, Yuzhao Yang e Xudong Chen. "The Glass-Transition Temperature of Supported PMMA Thin Films with Hydrogen Bond/Plasmonic Interface". Polymers 11, n. 4 (2 aprile 2019): 601. http://dx.doi.org/10.3390/polym11040601.

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The interfacial effect is one of the significant factors in the glass-transition temperature (Tg) of the polymeric thin film system, competing against the free surface effect. Herein, the Tgs of poly (methyl methacrylate) (PMMA) films with different thicknesses and substrates are studied by fluorescence measurements, focusing on the influence of interfacial effects on the Tgs. The strong interaction between PMMA and quartz substrate leads to increased Tgs with the decreased thickness of the film. The plasmonic silver substrate causes enhanced fluorescence intensity near the interface, resulting in the delayed reduction of the Tgs with the increasing film thickness. Moreover, as a proof of the interface-dependent Tgs, hydrogen bonds of PMMA/quartz and molecules orientation of PMMA/silver are explored by the Raman spectroscopy, and the interfacial interaction energy is calculated by the molecular dynamics simulation. In this study, we probe the inter-relationship between the interfacial interactions arising from the different substrates and the Tg behavior of polymer thin films.

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35

Hsu, Chia-Hsun, In-Cha Hsieh, Chia-Chi Tsou e Shui-Yang Lien. "Simulation and Experimental Study of Photogeneration and Recombination in Amorphous-Like Silicon Thin Films Deposited by 27.12 MHz Plasma-Enhanced Chemical Vapor Deposition". International Journal of Photoenergy 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/698026.

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Amorphous-like silicon (a-Si:H-like) thin films are prepared by 27.12 MHz plasma-enhanced chemical vapor deposition technique. The films are applied to p-i-n single junction thin film solar cells with varying i-layer thickness to observe the effects on the short-circuit current density, as well as the open-circuit voltage, fill factor, and conversion efficiency. The most significant experimental result is thatJschas two different behaviors with increasing the i-layer thickness, which can be related to carrier collection efficiency in the long wavelength region. Furthermore, technology computer-aided design simulation software is used to gain better insight into carrier generation and recombination of the solar cells, showing that for the i-layer thickness of 200 to 300 nm the generation dominates the carrier density and thusJsc, whereas for the i-layer thickness of 300 to 400 nm the recombination becomes the leading factor. The simulation results of cell performances are in good agreement with experimental data, indicating that our simulation has great reliability. In addition, the a-Si:H-like solar cells have low light-induced degradation, which in turn can have a great potential to be used for stable and high-efficiency solar cells.

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36

Ma, Lian Xiang, Yuan Zheng Tang e Yan He. "Thermal Conductivity of Solid Argon Nano-Films from Molecular Dynamics Simulations". Advanced Materials Research 221 (marzo 2011): 598–603. http://dx.doi.org/10.4028/www.scientific.net/amr.221.598.

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Thermal conductivity of L-J potential solid argon nano-films is calculated by equilibrium molecular dynamics (EMD) and nonequilibrium molecular dynamics (NEMD) simulations in the temperature range from 30K to 80K. A LAMMPS computer program has been modified based on classical molecular dynamics. It can be directly used to calculate the thermal conductivity of nano-films in the direction perpendicular to the film plane. Thermal conductivity calculated from this program is compared with experimental data. It is found that this computer program is competent to calculate the thermal conductivity of solid nano-films. It is also found that thermal conductivity is dependent on the simulation temperature and film thickness.

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37

Venner, C. H., e A. A. Lubrecht. "Numerical Simulation of a Transverse Ridge in a Circular EHL Contact Under Rolling/Sliding". Journal of Tribology 116, n. 4 (1 ottobre 1994): 751–61. http://dx.doi.org/10.1115/1.2927329.

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This paper investigates the influence of a transverse ridge on the film thickness in a circular EHL contact under rolling/sliding conditions. It is a numerical simulation of the optical EHL work of Kaneta et al. (1992). One of the purposes of this investigation is to check the validity of the algorithm and the Newtonian, isothermal lubricant assumption for film thickness predictions under these conditions (ph = 0.54 GPa). It will be shown that, both quantitatively, the film thickness on the central axis Y = 0, and qualitatively, the film thickness profile through “pseudo interference graphs”, the agreement between experiment and Newtonian isothermal theory is good. This supports the argument that the rheological and the thermal behavior of the fluid only slightly influence the film thickness and pressure distribution of the lightly loaded non-smooth contact case.

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38

Wolf, Marius, Sergey Solovyev e Fatemi Arshia. "Film thickness in elastohydrodynamically lubricated slender elliptic contacts: Part I – numerical studies of central film thickness". Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 236, n. 6 (6 ottobre 2021): 1043–55. http://dx.doi.org/10.1177/13506501211047756.

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In this paper, analytical equations for the central film thickness in slender elliptic contacts are investigated. A comparison of state-of-the-art formulas with simulation results of a multilevel elastohydrodynamic lubrication solver is conducted and shows considerable deviation. Therefore, a new film thickness formula for slender elliptic contacts with variable ellipticity is derived. It incorporates asymptotic solutions, which results in validity over a large parameter domain. It captures the behaviour of increasing film thickness with increasing load for specific very slender contacts. The new formula proves to be significantly more accurate than current equations. Experimental studies and discussions on minimum film thickness will be presented in a subsequent publication.

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39

Belim, Sergey V. "Investigation of Phase Transitions in Ferromagnetic Nanofilms on a Non-Magnetic Substrate by Computer Simulation". Materials 15, n. 7 (24 marzo 2022): 2390. http://dx.doi.org/10.3390/ma15072390.

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Magnetic properties of ferromagnetic nanofilms on non-magnetic substrate are examined by computer simulation. The substrate influence is modeled using the two-dimensional Frenkel-Kontorova potential. The film has a cubic crystal lattice. Cases of different ratio for substrate period and ferromagnetic film period are considered. The difference in film and substrate periods results in film deformations. These deformations result in a change in the magnetic properties of the film. The Ising model and the Metropolis algorithm are used for the study of magnetic properties. The dependence of Curie temperature on film thickness and substrate potential parameters is calculated. Cases of different values for the coverage factor are considered. The deformation of the film layers is reduced away from the substrate when it is compressed or stretched. The Curie temperature increases when the substrate is compressed and decreases when the substrate is stretched. This pattern is performed for films with different thicknesses. If the coating coefficient for the film is different from one, periodic structures with an increased or reduced concentration of atoms are formed in the film first layer. These structures are absent in higher layers.

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40

MAL, DIBYENDU, SUPARNA SINHA, TAPATI DUTTA, S. MITRA e SUJATA TARAFDAR. "FRACTAL CRACK PATTERNS IN LAPONITE FILMS AND THEIR SCALING BEHAVIOR". Fractals 14, n. 04 (dicembre 2006): 283–88. http://dx.doi.org/10.1142/s0218348x06003301.

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Abstract (sommario):

We study crack patterns in laponite films of different thickness. The patterns show a self-similarity under coarse-graining, the fractal dimension determined by box-counting has a value around 1.66, independent of film thickness. The cracks on layers of different thickness show a remarkable scaling bahavior. We have measured the cumulative area covered by the cracks versus minimum crack-width resolved. Curves representing crack area for different thickness collapse onto a single curve, when the crack widths are scaled by the film thickness.

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41

Zhikharev, P. V., e N. L. Shwartz. "Effect of mask-film properties on the initial GaAs nanowire growth stages". Journal of Physics: Conference Series 2227, n. 1 (1 marzo 2022): 012015. http://dx.doi.org/10.1088/1742-6596/2227/1/012015.

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Abstract The initial self-catalyze GaAs nanowire (NW) growth stages were studied using Monte Carlo simulation. We analyzed the effect of the mask-film etching rate with liquid gallium for different thicknesses on the initial nanowire formation stages. At a high etching rate NWs do not form on thick mask-films. A high etching rate of a thin film-mask can lead to lateral Ga drop motion over the crystalline substrate surface, which delays the nanowire formation onset. It is shown that, for the NW formation, it is necessary to maintain the correct ratio between the film thickness, etching rate, Ga and As2 flux intensities.

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42

Zhang, Xiao Ning, e Qing Wang. "Shielding Effectiveness Simulation of Brass-Iron Sandwich Films". Solid State Phenomena 124-126 (giugno 2007): 1613–16. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.1613.

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This paper presents a simulation method on shielding effectiveness(SE). The method is completely general and able to optimize shielding materials. We found a sandwich structure that it can efficiently shield plane wave, using this simulation method. The relationship of film thickness and its skin depth was investigated in this study. Two-dimensional curves and three-dimensional graphs were calculated by tri-layer SE formulas. A sandwich structure, which is 3μm iron-brass-iron films, is capable of excellent shielding properties: the SE is between -73dB and -100dB in the frequency range of 1MHz~10MHz. Another sandwich structure with 12μm thickness of brass-iron-brass films can offer -680dB shielding attenuation. Simulation experiments indicate that sandwich films with diamagnetic and ferromagnetic layers have outstanding contribution on SE.

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43

Jun, Sukky, Young Min Lee, Sung Youb Kim e Se Young Im. "Atomistic Simulations of Dislocation-Loop Glidings in Al(111) Nanoindentation". Key Engineering Materials 261-263 (aprile 2004): 735–40. http://dx.doi.org/10.4028/www.scientific.net/kem.261-263.735.

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Molecular dynamics simulation of nanoindentation on Al(111) surface is presented. The simulation is performed using the Ercolessi-Adams glue potential and the Berendsen thermostat. Boundary conditions of 'pseudo' thin film are imposed in order to focus on the dislocation motion in ultra-thin film. Nucleation and development of defects underneath the indenter tip are visualized, and the gliding patterns of dislocation loops are investigated with particular emphasis on the effect of film thickness. Simulation results show that the early emission of dislocation loop is highly dependent on the film thickness.

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44

Lou, Fei Yan, Qian Fa Deng e Ju Long Yuan. "Numerical and Experimental Research of the Slurry Film in Chemical Mechanical Polishing (CMP)". Advanced Materials Research 102-104 (marzo 2010): 669–74. http://dx.doi.org/10.4028/www.scientific.net/amr.102-104.669.

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A three-dimensional hydrodynamic lubrication model for chemical-mechanical polishing is presented based on the Reynolds equation and Reynolds boundary condition. By solving the Reynolds equation, the slurry film pressure distribution has been obtained. The effects of minimum film thickness and the wafer tile angle on the film pressure are analyzed, and the influence of the polishing applied load and rotation speed on slurry film thickness and tilt angle are discussed. At last, by experiment, it is found that the simulation results are similar to experiment results which film thickness is increasing with the increasing of rotation speed, decreasing of the applied load. It is proved that the simulation is reliable.

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45

YANG, ZHENYU, e YA-PU ZHAO. "SIZE-DEPENDENT ELASTIC PROPERTIES OF Ni NANOFILMS BY MOLECULAR DYNAMICS SIMULATION". Surface Review and Letters 14, n. 04 (agosto 2007): 661–65. http://dx.doi.org/10.1142/s0218625x07010032.

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Size-dependent elastic properties of Ni nanofilms are investigated by molecular dynamics (MD) simulations with embedded atom method (EAM). The surface effects are considered by calculating the surface relaxation, surface energy, and surface stress. The Young's modulus and yield stress are obtained as functions of thickness and crystallographic orientation. It is shown that the surface relaxation has important effects on the the elastic properties at nanoscale. When the surface relaxation is outward, the Young's modulus decreases with the film thickness decreasing, and vice versa. The results also show that the yield stresses of the films increase with the films becoming thinner. With the thickness of the nanofilms decreasing, the surface effects on the elastic properties become dominant.

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46

Ortiz, E., L. Martínez-Gómez, J. F. Valdés-Galicia, R. García, M. Anzorena e L. Martínez de la Escalera. "Skin protection against UV radiation using thin films of cerium oxide". Radioprotection 54, n. 1 (gennaio 2019): 67–70. http://dx.doi.org/10.1051/radiopro/2019002.

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In this work, we evaluated the efficiency of cerium oxide as sunscreen using titanium oxide as standard comparison material. Geant4 software was used to perform numerical simulation, we calculated the radiation dose that ultraviolet radiation deposits in a skin sample as a function of thin film thickness of the sunscreens. We found that in the interval between 5 and 15 nm of the thin film thickness and for wavelengths between 160 and 400 nm, cerium oxide has the potential to reduce the radiation dose more than 10% with respect to the same thickness band of titanium oxide. Using thin films of cerium oxide and titanium oxide with same thicknesses and greater than 45 nm, the difference in the attenuation of the radiation dose for both materials is less than 1%. The results lead us to propose cerium oxide as an alternative material to titanium oxide for the manufacture of sunscreens.

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47

Zhang, Yanqin, Zhiquan Zhang, Xiangbin Kong, Rui Li e Hui Jiang. "Application of dynamic mesh technology in the oil film flow simulation for hydrostatic bearing". Industrial Lubrication and Tribology 71, n. 1 (14 gennaio 2019): 146–53. http://dx.doi.org/10.1108/ilt-08-2017-0222.

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Abstract (sommario):

Purpose The purpose of this paper was to obtain the lubrication characteristics of heavy hydrostatic bearing in heavy equipment manufacturing industry through theoretical analysis and numerical simulation. Design/methodology/approach This paper discusses the influence of oil film thickness variation on velocity field, outlet-L and outlet-R flow velocity under the hydrostatic bearing running in no-load 0 N, load 400 KN, full load 1,500 KN and rotating speeds of 10 r/min, 20 r/min, 30 r/min, 40 r/min, 50 r/min and 60 r/min, by using dynamic mesh technology and FLUENT software. Findings When the working table rotates clockwise, in the change process of oil film thickness, the fluid flow pattern of the lubricating oil at the edge of the sealing oil is the rule of laminar flow, and the oil cavity has a vortex. The outlet-R flow velocity becomes higher and higher by increasing the bearing load and working table speed, and the flow velocity increases with the decrease in oil film thickness; the outlet-L flow velocity increases with the decrease in oil film thickness under low rotating speed (less than 10 r/min) condition and decreases with the decrease of oil film thickness under high rotating speed (more than 60 r/min) condition. Originality/value The influence of the oil film thickness on the flow state distribution of the oil film was analyzed under different working conditions, and the influence rules of oil film thickness on the flow velocity of hydrostatic bearing oil pad was obtained by using dynamic mesh technology.

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48

Liao, Ming-Jun, e Li-Qiang Duan. "Effect of the Hybrid Hydrophobic-Hydrophilic Nanostructured Surface on Explosive Boiling". Coatings 11, n. 2 (11 febbraio 2021): 212. http://dx.doi.org/10.3390/coatings11020212.

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Abstract (sommario):

The influence of different wettability on explosive boiling exhibits a significant distinction, where the hydrophobic surface is beneficial for bubble nucleation and the hydrophilic surface enhances the critical heat flux. Therefore, to receive a more suitable surface for the explosive boiling, in this paper a hybrid hydrophobic–hydrophilic nanostructured surface was built by the method of molecular dynamics simulation. The onset temperatures of explosive boiling with various coating thickness, pillar width, and film thicknesses were investigated. The simulation results show that the hybrid nanostructure can decrease the onset temperature compared to the pure hydrophilic surface. It is attributed to the effect of hydrophobic coating, which promotes the formation of bubbles and causes a quicker liquid film break. Furthermore, with the increase of the hydrophobic coating thickness, the onset temperature of explosive boiling decreases. This is because the process of heat transfer between the liquid film and the hybrid nanostructured surface is inevitably enhanced. In addition, the onset temperature of explosive boiling on the hybrid wetting surface decreases with the increase of pillar width and liquid film thickness.

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Hassan, M. A., M. B. Elfiky, Y. Nukman e Reza Mahmoodian. "Monte Carlo Simulation Model for Magnetron Sputtering Deposition". Advanced Materials Research 1105 (maggio 2015): 69–73. http://dx.doi.org/10.4028/www.scientific.net/amr.1105.69.

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Thin Film layers of metal are often prepared by magnetron sputtering technique for electronic, optical and micro/nanoelectromechanical systems. Usually, experimental work is a common way to find out the optimum deposition conditions and correlate between the thin film properties and the deposition parameters. However, experimental methods are very exhaustive, time and cost-consuming. A good simulation model which can provide the optimum operating conditions to avoid exhaustive experiments and reduce time and cost is highly recommended. Therefore, the present paper is focusing on the development of a computer simulation model of the deposition process in the magnetron sputtering system since such type of models is not well established yet. Monte Carlo (MC) simulation model has been developed to study the effects of deposition parameters on the deposition rate and thin film thickness uniformity. Titanium (Ti) samples were used as the target whereas argon (Ar) was the ambient inert gas. MC simulation has successfully predicted the optimum deposition rate and thickness of Ti thin films on the plastic substrate. The model also depicted the performance of magnetron deposition due to change of processing parameters. Comparison between the simulation and experimental results proved the validity of the proposed model.

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Николаенко, Ю. М., Н. Б. Эфрос e А. Н. Артемов. "Диффузия кислорода в La-=SUB=-0.8-=/SUB=-Sr-=SUB=-0.2-=/SUB=-MnO-=SUB=-3-delta-=/SUB=- пленках разной толщины на NdGaO-=SUB=-3-=/SUB=--подложках". Журнал технической физики 91, n. 12 (2021): 1957. http://dx.doi.org/10.21883/jtf.2021.12.51760.120-21.

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Abstract (sommario):

The results of investigation by the indirect method of step-by-step varying the oxygen content in the series of epitaxial La0.8Sr0.2Mn3- films on single-crystal NdGaO3 substrates are presented. Using numerical simulation we have revealed that the oxygen diffusion coefficient significantly decreases along the film thickness in the direction from the outer surface to the film-substrate interface under conditions of "compressive" mechanical stresses caused by the mismatch of the in-plane crystalline parameters of the film and substrate materials. In films of d≈12—75 nm thickness, the effect is manifested in the fact that the value of the diffusion coefficient in the vicinity of the outer surface of the films also decreases significantly as the thickness of the films decreases. The questions of the applicability of the indirect method for evaluating the oxygen content in thin epitaxial films, as well as other manifestations of effects caused by mechanical stresses are discussed.

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