Journal articles: 'Plasma Enhanced Physical Vapor Deposition (PEPVD)'

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Bhushan, Bharat, Andrew J. Kellock, Nam-Hee Cho, and Joel W. Ager. "Characterization of chemical bonding and physical characteristics of diamond-like amorphous carbon and diamond films." Journal of Materials Research 7, no. 2 (February 1992): 404–10. http://dx.doi.org/10.1557/jmr.1992.0404.

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Diamond-like (amorphous) carbon (DLC) films were prepared by dc magnetron sputtering and plasma enhanced chemical vapor deposition (PECVD) and diamond films were prepared by microwave plasma enhanced chemical vapor deposition (MPECVD). For the first time, chemical and mechanical characterization of the films from each category are carried out systematically and a comparison of the chemical and physical properties is provided. We find that DLC coatings produced by PECVD are superior in microhardness and modulus of elasticity to those produced by sputtering. PECVD films contain a larger fraction of sp3-bonding than the sputtered hydrogenated carbon films. Chemical and physical properties of the diamond films appear to be close to those of bulk diamond.

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SAMPATH KUMAR, T., A. VINOTH JEBARAJ, K. SIVAKUMAR, E. SHANKAR, and N. TAMILOLI. "CHARACTERIZATION OF TiCN COATING SYNTHESIZED BY THE PLASMA ENHANCED PHYSICAL VAPOUR DEPOSITION PROCESS ON A CEMENTED CARBIDE TOOL." Surface Review and Letters 25, no. 08 (December 2018): 1950028. http://dx.doi.org/10.1142/s0218625x19500288.

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In the present investigation, Titanium Carbonitride (TiCN) coating was deposited on a cemented carbide substrate, by means of Plasma Enhanced Physical Vapour Deposition (PEPVD) process. The microstructure of the deposited film was characterized using the Scanning Electron Microscope (SEM). Highly dense, less porous and uniformly distributed TiCN coating was observed on the coated surface. X-Ray diffraction analysis was carried out to access the phases present in the coated layer. The scratch resistance and hardness were measured using the scratch tester and Nanoindenter, respectively. The TiCN coating gives higher hardness and superior scratch resistance when compared to the substrate. The surface morphology of the coated film was characterized using the Atomic Force Microscope (AFM) and was found that the surface roughness was lesser for TiCN coating when compared to cemented carbide substrate. The intensified TiCN coating on the substrate will be useful in improving the surface behavior of cemented carbide cutting tool.

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Lee, Won Jun, Min Ho Chun, Kwang Su Cheong, Kwang Chol Park, Chong Ook Park, Guo Zhong Cao, and Sa Kyun Rha. "Characteristics of SiO₂ Film Grown by Atomic Layer Deposition as the Gate Insulator of Low-Temperature Polysilicon Thin-Film Transistors." Solid State Phenomena 124-126 (June 2007): 247–50. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.247.

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SiO2 films were prepared by atomic layer deposition (ALD) technique, and their physical and electrical properties were characterized for being applied as a gate insulator of low-temperature polysilicon thin-film transistors. ALD SiO2 films were deposited at 350–400 oC using alternating exposures of SiH2Cl2 and O3/O2, and the characteristics of the deposited films were improved with increasing deposition temperature. The ALD films deposited at 400 oC exhibited integrity, surface roughness and leakage current better than those of the conventional plasma-enhanced chemical vapor deposition (PECVD) films.

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Wang, Zhi Jian, and Xiao Feng Shang. "The Simulation of Polycrystalline Silicon Thin Film Deposition in PECVD System." Advanced Materials Research 189-193 (February 2011): 2032–36. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.2032.

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Taking Silicon tetrachloride (SiCl4) and hydrogen (H2) as the reaction gas, by the method of plasma-enhanced chemical vapor deposition (PECVD), this paper simulates the deposition process of polycrystalline silicon thin film on the glass substrates in the software FLUENT. Three dimensional physical model and mathematics model of the simulated area are established. The reaction mechanism including main reaction equation and several side equations is given during the simulation process. The simulation results predict the velocity field, temperature distribution, and concentration profiles in the PECVD reactor. The simulation results show that the deposition rate of silicon distribution is even along the circumference direction, and gradually reduced along the radius direction. The deposition rate is about 0.005kg/(m2•s) at the center. The simulated result is basically consistent with the practical one. It means that numerical simulation method to predict deposition process is feasible and the results are reliable in PECVD system.

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Liu, Bangwu, Sihua Zhong, Jinhu Liu, Yang Xia, and Chaobo Li. "Silicon Nitride Film by Inline PECVD for Black Silicon Solar Cells." International Journal of Photoenergy 2012 (2012): 1–5. http://dx.doi.org/10.1155/2012/971093.

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The passivation process is of significant importance to produce high-efficiency black silicon solar cell due to its unique microstructure. The black silicon has been produced by plasma immersion ion implantation (PIII) process. And the Silicon nitride films were deposited by inline plasma-enhanced chemical vapor deposition (PECVD) to be used as the passivation layer for black silicon solar cell. The microstructure and physical properties of silicon nitride films were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), spectroscopic ellipsometry, and the microwave photoconductance decay (μ-PCD) method. With optimizing the PECVD parameters, the conversion efficiency of black silicon solar cell can reach as high as 16.25%.

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Kluska, Stanisława, Elżbieta Pamuła, Stanisława Jonas, and Zbigniew Grzesik. "Surface Modification of Polyetheretherketone by Helium/nitrogen and Nitrous Oxide Plasma Enhanced Chemical Vapour Deposition." High Temperature Materials and Processes 33, no. 2 (April 1, 2014): 147–53. http://dx.doi.org/10.1515/htmp-2013-0022.

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AbstractThe surface of the polyetheretherketone (PEEK) samples was modified by the plasma enhanced chemical vapor deposition (PECVD) in the mixture of He and N2 as well as in the N2O atmosphere. Morphological characterization of the PEEK as well as its surface roughness, chemical structure, and surface free energy were investigated by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and sessile drop technique, respectively. The highest increase in the polar component of the total surface energy was observed for PEEK modified by He+N2 plasma, which correlated with significant increase in the concentration of oxygen and nitrogen-containing chemical functionalities as revealed by XPS. For PEEK submitted to N2O plasma treatment significant changes in surface topography and increase in roughness were observed, but changes in surface chemistry and surface free energy were mild.

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Jürgensen, Lasse, Michael Frank, David Graf, Isabel Gessner, Thomas Fischer, Katharina Welter, Wolfram Jägermann, and Sanjay Mathur. "Nanostructured IrOx Coatings for Efficient Oxygen Evolution Reactions in PV-EC Setup." Zeitschrift für Physikalische Chemie 234, no. 5 (May 26, 2020): 911–24. http://dx.doi.org/10.1515/zpch-2019-1450.

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AbstractNew heteroleptic iridium compounds exhibiting high volatility and defined thermal decomposition behavior were developed and tested in plasma-enhanced chemical vapor deposition (PECVD). The iridium precursor [(COD)Ir(TFB-TFEA)] (COD = 1,5-cyclooctadiene; TFB-TFEA = N-(4,4,4-Trifluorobut-1-en-3-on)-6,6,6-trifluoroethylamin) unifies both reactivity and sufficient stability through its heteroleptic constitution to offer a step-by-step elimination of ligands to provide high compositional purity in CVD deposits. The substitution of neutral COD ligands against CO groups further increased the volatility of the precursor. PECVD experiments with unambiguously characterized Ir compounds (single crystal X-ray diffraction analysis) demonstrated their suitability for an atom-efficient (high molecule-to-precursor yield) gas phase deposition of amorphous iridium oxide (IrOx) phases. Thin films of IrOx were well suited as electrocatalyst in oxygen evolution reaction so that an efficient coupled system in combination with solar cells is viable to perform water-splitting reaction without external bias.

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Vitiello, J., F. Piallat, and L. Bonnet. "Alternative deposition solution for cost reduction of TSV integration." International Symposium on Microelectronics 2017, no. 1 (October 1, 2017): 000135–39. http://dx.doi.org/10.4071/isom-2017-tp52_034.

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Abstract As one of the key enabler of 3D integration, Through Silicon Via (TSV) was widely investigated but not largely adopted in the advanced packaging industry. At the present time, TSV key films, i.e. isolation, barrier and Cu seed layers, are depending on (Plasma Enhanced) Chemical Vapor Deposition ((PE)CVD) and Physical Vapor Deposition (PVD) systems in high volume manufacturing. Those deposition methods are not able to answer actual TSV needs: thick and conformal layers. They have forced engineers to compensate with other TSV fabrication steps while degrading fabrication cost. The innovative Fast Atomic Sequential Technology (F.A.S.T.®), a unique combination of optimized CVD reactor with Atomic Layer Deposition (ALD) pulsing capability, has been extensively evaluated to answer the thick and conformal layer request of TSV integration scheme while reducing integration cost. Based on commercially available molecules, actual isolation, copper barrier and Cu seed materials can be layered with advantageous conformality in TSV with aspect ratio up to 20:1. Furthermore, extended process window is at reach with the technique, thanks to additional parameters enabling fine tuning of the layer's properties to fit actual needs and future requirements. Assisted by plasma to deposit SiO2 liner, and TiN copper barrier, or combined with reducing gas for Cu seed deposition, highly conformal films compared to PVD or PECVD can be obtained while offering deposition rate much higher than PEALD. Additionally, a unique in-situ cleaning capability was also developed to remove deposition material from the reactor walls in the Cu Seed deposition chamber, thus answering the requirements of high volume manufacturing players.

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Echeverría, Elena, George Peterson, Bin Dong, Simeon Gilbert, Adeola Oyelade, Michael Nastasi, Jeffry A. Kelber, and Peter A. Dowben. "Band Bending at the Gold (Au)/Boron Carbide-Based Semiconductor Interface." Zeitschrift für Physikalische Chemie 232, no. 5-6 (May 24, 2018): 893–905. http://dx.doi.org/10.1515/zpch-2017-1038.

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Abstract We have used X-ray photoemission spectroscopy to study the interaction of gold (Au) with novel boron carbide-based semiconductors grown by plasma-enhanced chemical vapor deposition (PECVD). Both n- and p-type films have been investigated and the PECVD boron carbides are compared to those containing aromatic compounds. In the case of the p-type semiconducting PECVD hydrogenated boron carbide samples, the binding energy of the B(1s) core level shows a shift to higher binding energies as the Au is deposited, an indication of band bending and possibly Schottky barrier formation. In the case of the n-type boron carbide semiconductors the interaction at the interface is more typical of an ohmic contact. Addition of the aromatic compounds increases the change in binding energies on both n-type and p-type PECVD boron carbide semiconductors, and the gold appears to diffuse into the PECVD boron carbides alloyed with aromatic moieties.

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Yan, Bao Jun, Shu Lin Liu, Xiao Wei Liu, and Ting Ting Jiang. "Effect of Hydrogen Dilution Ratio and Substrate Roughness on the Microstructure of Intrinsic Microcrystalline Silicon Thin Films." Advanced Materials Research 936 (June 2014): 202–6. http://dx.doi.org/10.4028/www.scientific.net/amr.936.202.

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Intrinsic microcrystalline silicon (μc-Si:H) thin films were deposited on four kinds of substrates (polished quartz glass: PG, Rough quartz glass: RG, Textured SnO2:F coated glass: TG, Textured ZnO:Al coated glass: ZG) by 13.56 MHz plasma enhanced chemical vapor deposition (PECVD) with different hydrogen dilution ratio (RH=H2/SiH4) under the pressure of 2 Torr. The film thickness, crystalline volume fraction (XC) and substrate surface roughness (Ra) were measured by surface profilometer, Raman spectra and atom force microscopy (AFM), respectively. The results revealed that with the increase of RH, the deposition rate decreased and XC increased monotonously for the films deposited on the same substrate, but the substrate Ra had an obvious impact on the film microstructure. A physical model was proposed to illustrate the growth of the μc-Si:H thin films deposited on substrates with different Ra.

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Polak, Peter Lubomir, Ronaldo Domingues Mansano, Rui Alberto Silva, Igor Proença Silva, and Maria Cristina Ribeiro. "Physical Characterization of Plasma Deposited Polymeric Proton Exchange Membrane Used in Fuel Cells." Materials Science Forum 638-642 (January 2010): 1158–63. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.1158.

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The performance of fuel cells is largely dependent on the properties of the membrane electrode assembly (MEA) which consists of a polymer electrolyte membrane and carbon based electrodes. The aim of this work was to obtain new polymer membranes and carbon thin films (for comparison) by Plasma Enhanced Chemical Vapor Deposition (PECVD) and proceed to their physical characterization in order to be able to choose the best conditions that may lead to outstanding proton exchange membranes. The films were deposited on silicon wafers and were analyzed by Scanning Electron Microscopy and Energy Dispersive Spectroscopy (SEM/EDS), Electron Spectroscopy for Chemical Analysis and X-Ray Photoelectron Spectroscopy (ESCA-XPS), Atomic Force Microscopy (AFM), Fourier Transform Infrared Spectroscopy (FTIR) and Rutherford Backscattering Spectrometry (RBS). SEM/EDS and XPS analysis have shown that the chemical composition of the films varied as a function of the plasma (relative percentages of the reactant gases CH4 and SF6) while variation of the pressure and RF power did not have a marked effect on the topographic quality and composition of the membranes. AFM analysis, as well as SEM, made possible to observe the topography of the membranes showing that the films are very smooth with some localized defects. Futhermore, AFM micrographs have shown that the roughness (root mean square - RMS) of the membranes have peak to valley differences in the order of some nanometers. RBS and Profilometer techniques indicated that the deposition rate of the films is not linearly dependent on the plasma composition while FTIR spectroscopy has shown the presence of the perfluorinated sulphonate groups.

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Jozwiak, Lukasz, Jacek Balcerzak, and Jacek Tyczkowski. "Plasma-Deposited Ru-Based Thin Films for Photoelectrochemical Water Splitting." Catalysts 10, no. 3 (March 1, 2020): 278. http://dx.doi.org/10.3390/catal10030278.

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Plasma-enhanced chemical vapor deposition (PECVD) was used to produce new Ru-based thin catalytic films. The surface molecular structure of the films was examined by X-ray photoelectron spectroscopy (XPS). To determine the electro- and photoelectrochemical properties, the oxygen evolution reaction (OER) process was investigated by linear sweep voltammetry (LSV) at pH = 13.6. It was found that Ru atoms were mainly in the metallic state (Ru0) in the as-deposited films, whereas after the electrochemical stabilization, higher oxidation states, mainly Ru+4 (RuO2), were formed. The stabilized films exhibited high catalytic activity in OER—for the electrochemical process, the onset and η10 overpotentials were approx. 220 and 350 mV, respectively, while for the photoelectrochemical process, the pure photocurrent density of about 160 mA/cm2 mg was achieved at 1.6 V (vs. reversible hydrogen electrode (RHE)). The plasma-deposited RuOX catalyst appears to be an interesting candidate for photoanode material for photoelectrochemical (PEC) water splitting.

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Yoo, Woo Sik, Richard Swope, Barbara Sparks, and David Mordo. "Comparison of C2F6 and FASi-4 as fluorine dopant sources in plasma enhanced chemical vapor deposited fluorinated silica glass films." Journal of Materials Research 12, no. 1 (January 1997): 70–74. http://dx.doi.org/10.1557/jmr.1997.0012.

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Fluorine doping of silicon dioxide films in tetraethylorthosilicate (TEOS)-based plasma enhanced chemical vapor deposition (PECVD) processes was investigated using two fluorine dopant sources, C2F6 and 1,2 bis[methyldifluorosilyl]ethane (FASi-4). Much as TEOS-based undoped silica glass (USG) films display improved step coverage over silane-based USG films, it was suspected that fluorinated silica glass (FSG) films deposited using the relatively new TEOS-based fluorine source FASi-4 might have improved gap fill capabilities as compared to FSG films deposited using gas-based C2F6 fluorine sources. The physical properties and intermetal gap filling capabilities of FSG films deposited using FASi-4 as a fluorine dopant source were compared with the properties of FSG films deposited using C2F6 as a fluorine source. Fluorine dopant levels in the films were found to be linear functions of C2F6TEOS and FASi-4yTEOS ratios. The RI, film stress, and gap fill capability were found to be strongly dependent on the Si–F content in the film regardless of dopant source reagents. Improved gap fill characteristics were observed in films doped with FASi-4 at a given Si–F/Si–O% as compared to C2F6-based FSG films. Dopant source dependence of doping characteristics, physical properties, and gap filling capability of FSG films is reported.

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Chiou, W. A., M. S. Wong, F. R. Chen, D. X. Li, R. P. H. Chang, and M. Meshii. "Techniques in preparing TEM specimens of diamond thin films." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 716–17. http://dx.doi.org/10.1017/s0424820100155554.

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Diamond, with its unique combination of optical, physical, mechanical, and electrical properties, has provided a superior potential for industrial and military applications. It has caught the attention of a growing number of researchers over the past decade. The recent development of low-pressure vapor deposition of diamond film has greatly increased the prospects for the practical utilization of diamond. To use a diamond film, the nature of the interface between diamond film and substrate must be understood. This paper presents three different techniques in preparing diamond thin films specimens for TEM study of the interfacial structure between diamond and substrate as well as the internal structure of diamond crystals.Diamond crystallites and films produced by radio frequency (RF) and microwave (MW) plasma enhanced chemical vapor deposition (PECVD) techniques were deposited on Si (100), polycrystalline Mo, and Cu substrates (925°C) at 40 mbar, with 0.5% methane and 0.2% oxygen in hydrogen gas at a total flow rate of 200 seem for MWPECVD and 2000 seem for RFPECVD. To examine the internal and interfacial structures of the diamond film on different substrates, three techniques were employed: (1) the chemical etching technique, which removes substrates then the substrate-free diamond film was supported on a Cu grid, (2) the conventional epoxy-embedding technique for cross-section study, and (3) the direct deposition of diamond crystallites on metal grids.

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Ricci, M., M. Trinquecoste, F. Auguste, R. Canet, P. Delhaes, C. Guimon, G. Pfister-Guillouzo, B. Nysten, and J. P. Issi. "Relationship between the structural organization and the physical properties of PECVD nitrogenated carbons." Journal of Materials Research 8, no. 3 (March 1993): 480–88. http://dx.doi.org/10.1557/jmr.1993.0480.

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By a Plasma Enhanced Chemical Vapor Deposition process (PECVD), we are able to prepare nitrogenated amorphous carbon materials around room temperature from methane and nitrogen gas as precursors. We have also used chlorine gas as an additive to reduce the hydrogen content of our samples. Starting from the “as-deposited” materials, we have investigated their thermal stability by successive heat treatments up to 1400 °C. These compounds suffer a weight loss mostly due to the hydrogen departure. They become nonfusible and it turns out that nitrogen, chemically bound to sp2 hybridized carbons, induces some changes in the physical properties. In order to understand the relationship between the local structural organization and the physical characteristics, we have investigated different spectroscopic techniques such as Nuclear Magnetic Resonance, IR Absorption, and X-ray Photoelectron Spectroscopy. We have also investigated several transport properties: (i) The dc electrical conductivity shows a kind of metal/insulator transition around 700 °C. The temperature dependence for the conductive samples gives evidence for a pseudogap associated with the presence of localized states, (ii) The thermal conductivity exhibits, for the as-deposited compound, a very low value varying slowly with temperature; its magnitude as well as its temperature dependence, characteristic of noncrystalline materials, are modified by the annealing process. Finally, an electronic band model is proposed, explaining the structural evolution through a kind of Mott–Anderson pseudotransition.

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Grigoriev, Sergey N., Marina A. Volosova, Sergey V. Fedorov, and Mikhail Mosyanov. "Influence of DLC Coatings Deposited by PECVD Technology on the Wear Resistance of Carbide End Mills and Surface Roughness of AlCuMg2 and 41Cr4 Workpieces." Coatings 10, no. 11 (October 28, 2020): 1038. http://dx.doi.org/10.3390/coatings10111038.

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The primary purpose of this work was to study the effectiveness of using diamond-like coatings (DLC) to increase the wear resistance of carbide end mills and improve the surface quality of the processed part when milling aluminum alloy and low-carbon steel. The functional role of forming an adhesive sublayer based on (CrAlSi)N immediately before the application of the external DLC film by plasma-enhanced chemical vapor deposition (PECVD) technology in the composition of a multicomponent gas mixture containing tetramethylsilane was established in the article. The article shows the degree of influence of the adhesive sublayer on important physical, mechanical, and structural characteristics of DLCs (hardness, modulus of elasticity, index of plasticity, and others). A quantitative assessment of the effect of single-layer DLCs and double-layer (CrAlSi)N/DLCs on the wear rate of end mills during operation and the surface roughness of machined parts made of aluminum alloy AlCuMg2 and low-carbon steel 41Cr4 was performed.

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Jiang, Pei-Cheng, Yu-Ting Chow, Chi-Wei Chien, Cheng-Hsun-Tony Chang, and Chii-Ruey Lin. "Silica Layer Used in Sensor Fabrication from a Low-Temperature Silane-Free Procedure." Chemosensors 9, no. 2 (February 4, 2021): 32. http://dx.doi.org/10.3390/chemosensors9020032.

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Silica (SiO2, silicon dioxide—a dielectric layer commonly used in electronic devices) is widely used in many types of sensors, such as gas, molecular, and biogenic polyamines. To form silica films, core shell or an encapsulated layer, silane has been used as a precursor in recent decades. However, there are many hazards caused by using silane, such as its being extremely flammable, the explosive air, and skin and eye pain. To avoid these hazards, it is necessary to spend many resources on industrial safety design. Thus, the silica synthesized without silane gas which can be determined as a silane-free procedure presents a clean and safe solution to manufactures. In this report, we used the radio frequency (rf = 13.56 MHz) plasma-enhanced chemical vapor deposition technique (PECVD) to form a silica layer at room temperature. The silica layer is formed in hydrogen-based plasma at room temperature and silane gas is not used in this process. The substrate temperature dominates the silica formation, but the distance between the substrate and electrode (DSTE) and the methane additive can enhance the formation of a silica layer on the Si wafer. This silane-free procedure, at room temperature, is not only safer and friendlier to the environment but is also useful in the fabrication of many types of sensors.

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Purna Chandra Rao, B., R. Maheswaran, Shivaraman Ramaswamy, Ojas Mahapatra, C. Gopalakrishanan, and D. John Thiruvadigal. "Low Temperature Growth of Carbon Nanostructures by Radio Frequency‐Plasma Enhanced Chemical Vapor Deposition (Low Temperature Growth of Carbon Nanostructures by RF‐PECVD)." Fullerenes, Nanotubes and Carbon Nanostructures 17, no. 6 (December 2009): 625–35. http://dx.doi.org/10.1080/15363830903291408.

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Cheng, Chih-Hsien, and Gong-Ru Lin. "Si-QD Synthesis for Visible Light Emission, Color Conversion, and Optical Switching." Materials 13, no. 16 (August 17, 2020): 3635. http://dx.doi.org/10.3390/ma13163635.

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This paper reviews the developing progress on the synthesis of the silicon quantum dots (Si-QDs) via the different methods including electrochemical porous Si, Si ion implantation, and plasma enhanced chemical vapor deposition (PECVD), and exploring their featured applications for light emitting diode (LED), color-converted phosphors, and waveguide switching devices. The characteristic parameters of Si-QD LED via different syntheses are summarized for discussion. At first, the photoluminescence spectra of Si-QD and accompanied defects are analyzed to distinguish from each other. Next, the synthesis of porous Si and the performances of porous Si LED reported from different previous works are compared in detail. Later on, the Si-QD implantation in silicide (SiX) dielectric films developed to solve the instability of porous Si and their electroluminescent performances are also summarized for realizing the effect of host matrix to increase the emission quantum efficiency. As the Si-ion implantation still generates numerous defects in host matrix owing to physical bombardment, the PECVD method has emerged as the main-stream methodology for synthesizing Si-QD in SiX semiconductor or dielectric layer. This method effectively suppresses the structural matrix imperfection so as to enhance the external quantum efficiency of the Si-QD LED. With mature synthesis technology, Si-QD has been comprehensively utilized not only for visible light emission but also for color conversion and optical switching applications in future academia and industry.

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Zaghloul, Usama, George J. Papaioannou, Bharat Bhushan, Fabio Coccetti, Patrick Pons, and Robert Plana. "New insights into reliability of electrostatic capacitive RF MEMS switches." International Journal of Microwave and Wireless Technologies 3, no. 5 (September 1, 2011): 571–86. http://dx.doi.org/10.1017/s1759078711000766.

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Among other reliability concerns, the dielectric charging is considered the major failure mechanism which hinders the commercialization of electrostatic capacitive radio frequency micro-electro-mechanical systems (RF MEMS) switches. In this study, Kelvin probe force microscopy (KPFM) surface potential measurements have been employed to study this phenomenon. Several novel KPFM-based characterization methods have been proposed to investigate the charging in bare dielectric films, metal–insulator–metal (MIM) capacitors, and MEMS switches, and the results from these methods have been correlated. The used dielectric material is plasma-enhanced chemical vapor deposition (PECVD) silicon nitride. The SiNx films have been charged by using a biased atomic force microscope (AFM) tip or by electrically stressing MIM capacitors and MEMS switches. The influence of several parameters on the dielectric charging has been studied: dielectric film thickness, deposition conditions, and under layers. Fourier transform infra-red (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) material characterization techniques have been used to determine the chemical bonds and compositions, respectively, of the SiNx films. The data from the physical material characterization have been correlated to the KPFM results. The study provides an accurate understanding of the charging/discharging processes in dielectric films implemented in electrostatic MEMS devices.

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Chen, Jiang, Chen, Feng, and Wu. "Preparation, Characterization, and Performance Control of Nanographitic Films." Nanomaterials 9, no. 4 (April 17, 2019): 628. http://dx.doi.org/10.3390/nano9040628.

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Using methane as a carbon source, low-dimensional carbon nanomaterials were obtained in this work. The films were deposited directly on glass substrates by radio frequency plasma-enhanced chemical vapor deposition (RF-PECVD). The configuration and compositions of this nanographite films were identified by X-ray photoelectron spectroscopy (XPS) as carbon in sp2 bonding form. Raman spectral characterization verified the configuration of the films to be hexatomic ring of carbon atoms. As a result, they were found to be nanographite films (NGFs). Also, the atomic force microscopy (AFM) topography and Raman spectra of different areas demonstrated the diversity of the films at the nano scale. The high light-transmitting and electron mobility indicated that the NGFs possessed excellent optic-electronic properties and could be used as good photoelectrical function materials. Furthermore, the physical and chemical growth mechanism of NGFs were analyzed by PECVD. NGFs could be obtained in a controlled process by modulating the growth conditions. In this work, the complicated transfer process commonly used for optoelectronic devices could be avoided. Also, by growing the films directly on a glass substrate, the quality degradation of the film was not a problem. This work can further promote the development of next-generation electronic or optoelectronic function materials, especially for their application in transparent conductive electrode fields.

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Kierzkowska-Pawlak, Hanna, Małgorzata Ryba, Maciej Fronczak, Ryszard Kapica, Jan Sielski, Maciej Sitarz, Patryk Zając, Klaudia Łyszczarz, and Jacek Tyczkowski. "Enhancing CO2 Conversion to CO over Plasma-Deposited Composites Based on Mixed Co and Fe Oxides." Catalysts 11, no. 8 (July 22, 2021): 883. http://dx.doi.org/10.3390/catal11080883.

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The hydrogenation of CO2 to produce CO and H2O, known as reverse-water-gas shift reaction (RWGS) is considered to be an important CO2 valorization pathway. This work is aimed at proposing the thin-film catalysts based on iron and cobalt oxides for this purpose. A series of Fe–Co nanocomposites were prepared by the plasma-enhanced chemical vapor deposition (PECVD) from organic cobalt and iron precursors on a wire-mesh support. The catalysts were characterized by SEM/EDX, XPS, XRD, and Raman spectroscopy and studied for hydrogenation of CO2 in a tubular reactor operating in the temperature range of 250–400 °C and atmospheric pressure. The Co-based catalyst, containing crystalline CoO phase, exhibited high activity toward CH4, while the Fe-based catalyst, containing crystalline Fe2O3/Fe3O4 phases, was less active and converted CO2 mainly into CO. Regarding the Fe–Co nanocomposites (incl. Fe2O3/Fe3O4 and CoO), even a small fraction of iron dramatically inhibited the production of methane. With increasing the atomic fraction of iron in the Fe–Co systems, the efficiency of the RWGS reaction at 400 °C increased up to 95% selectivity to CO and 30% conversion of CO2, which significantly exceeded the conversion for pure iron–based films (approx. 9%). The superior performance of the Fe–Co nanocomposites compared to “pure” Co and Fe–based films was proposed to be explained by assuming changes in the electronic structure of the catalyst resulting from the formation of p–n junctions between nanoparticles of cobalt and iron oxides.

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Jašek, Ondřej, Petr Synek, Lenka Zajíčková, Marek Eliáš, and Vít Kudrle. "Synthesis of Carbon Nanostructures by Plasma Enhanced Chemical Vapour Deposition at Atmospheric Pressure." Journal of Electrical Engineering 61, no. 5 (September 1, 2010): 311–13. http://dx.doi.org/10.2478/v10187-011-0049-9.

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Synthesis of Carbon Nanostructures by Plasma Enhanced Chemical Vapour Deposition at Atmospheric PressureCarbon nanostructures present the leading field in nanotechnology research. A wide range of chemical and physical methods was used for carbon nanostructures synthesis including arc discharges, laser ablation and chemical vapour deposition. Plasma enhanced chemical vapour deposition (PECVD) with its application in modern microelectronics industry became soon target of research in carbon nanostructures synthesis. Selection of the ideal growth process depends on the application. Most of PECVD techniques work at low pressure requiring vacuum systems. However for industrial applications it would be desirable to work at atmospheric pressure. In this article carbon nanostructures synthesis by plasma discharges working at atmospheric pressure will be reviewed.

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24

Suhr, H., A. Etsp�ler, E. Feurer, and S. Kraus. "Alloys prepared by plasma-enhanced chemical vapor deposition (PECVD)." Plasma Chemistry and Plasma Processing 9, no. 2 (June 1989): 217–23. http://dx.doi.org/10.1007/bf01054282.

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25

Blain, S., J. E. Klemberg-Sapieha, M. R. Wertheimer, and S. C. Gujrathi. "Silicon oxynitride from microwave plasma: fabrication and characterization." Canadian Journal of Physics 67, no. 4 (April 1, 1989): 190–94. http://dx.doi.org/10.1139/p89-033.

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Plasma silicon nitride (P-SiN), oxynitride (P-SiON), and silicon dioxide (P-SiO2) films have been prepared from SiH4–NH3–N2O mixtures in a large volume microwave plasma (LMPR, 2.45 GHz) apparatus at TS = 280 °C. Film compositions, determined by X-ray photoelectron spectroscopy and nuclear elastic recoil detection analysis, reveal about 15 at.% hydrogen in P-SiN, <2% in P-SiO2, and intermediate values in P-SiON. Various physicochemical and electrical properties (density, refractive index, intrinsic stress, permittivity, and conductivity) vary systematically with film composition, O/(O + N), determined from the above analyses. The present microwave plasma enhanced chemical vapour deposition (PECVD) films compare favorably with the best PECVD and low pressure chemical vapour deposition (LPCVD) materials reported in the literature.

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Cheng, Jifang, Catherine Jimenez, Jacob P. Bell, Ingrid E. Anderson, Chito Kendrick, Yongan Yang, Reuben T. Collins, and S. Kim R. Williams. "Passivation, Separation and Characterization of Plasma Synthesized Silicon Nanoparticles." MRS Proceedings 1493 (2013): 117–19. http://dx.doi.org/10.1557/opl.2013.404.

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ABSTRACTSilicon nanoparticles (Si NPs) were synthesized by plasma enhanced chemical vapor deposition (PECVD) using silane as a silicon source. Allylamine was used as passivation ligands to form water-soluble Si NPs. Finally, aqueous asymmetric flow field-flow fractionation was used to successfully separate the polydisperse Si NPs into monodisperse Si NP fractions.

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27

Prikryl, Radek, Pavel Otrisal, Vladimir Obsel, Lubomír Svorc, Radovan Karkalic, and Jan Buk. "Protective Properties of a Microstructure Composed of Barrier Nanostructured Organics and SiOx Layers Deposited on a Polymer Matrix." Nanomaterials 8, no. 9 (August 31, 2018): 679. http://dx.doi.org/10.3390/nano8090679.

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The SiOx barrier nanocoatings have been prepared on selected polymer matrices to increase their resistance against permeation of toxic substances. The aim has been to find out whether the method of vacuum plasma deposition of SiOx barrier nanocoatings on a polyethylene terephthalate (PET) foil used by Aluminium Company of Canada (ALCAN) company (ALCAN Packaging Kreuzlingen AG (SA/Ltd., Kreuzlingen, Switzerland) within the production of CERAMIS® packaging materials with barrier properties can also be used to increase the resistance of foils from other polymers against the permeation of organic solvents and other toxic liquids. The scanning electron microscopy (SEM) microstructure of SiOx nanocoatings prepared by thermal deposition from SiO in vacuum by the Plasma Assisted Physical Vapour Deposition (PA-PVD) method or vacuum deposition of hexamethyldisiloxane (HMDSO) by the Plasma-enhanced chemical vapour deposition (PECVD) method have been studied. The microstructure and behavior of samples when exposed to a liquid test substance in relation to the barrier properties is described.

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MANN, M., K. B. K. TEO, W. I. MILNE, and T. TESSNER. "DIRECT GROWTH OF MULTI-WALLED CARBON NANOTUBES ON SHARP TIPS FOR ELECTRON MICROSCOPY." Nano 01, no. 01 (July 2006): 35–39. http://dx.doi.org/10.1142/s1793292006000094.

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The favorable electron optical properties of carbon nanotubes (CNTs) have been studied in detail, but the application to electron sources has been limited by the complexity of the fabrication process. We report the use of Plasma Enhanced Chemical Vapor Deposition (PECVD) for the direct deposition of multi-walled CNTs onto the apex of sharply etched tungsten tips, aligned to the vertical axis of the tips. We show that these emitters have excellent stability.

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LEI, QING-SONG, ZHI-MENG WU, JIAN-PING XI, XIN-HUA GENG, YING ZHAO, and JIAN SUN. "DEVELOPMENT OF HIGHLY CONDUCTIVE BORON-DOPED MICROCRYSTALLINE SILICON FILMS FOR APPLICATION IN SOLAR CELLS." International Journal of Modern Physics B 20, no. 03 (January 30, 2006): 303–14. http://dx.doi.org/10.1142/s0217979206033292.

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We have examined the deposition of highly conductive boron-doped microcrystalline silicon (μc- Si:H ) films for application in solar cells. Depositions were conducted in a very high frequency plasma enhanced chemical vapor deposition (VHF PECVD) chamber. In the deposition processes, various substrate temperatures (TS) were applied. Highly conductive p-type microcrystalline silicon films were obtained at substrate temperature lower than 210°C. The factors that affect the conductivity of the films were investigated. Results suggest that the dark conductivity, which was determined by the Hall mobility and carrier concentration, is influenced by the structure. The properties of the films are strongly dependent on the substrate temperature. With TS increasing, the dark conductivity (σd) increases initially; reach the maximum values at certain TS and then decrease. Also, we applied the boron-doped μc- Si:H as p-layers to the solar cells. An efficiency of about 8.5% for a solar cell with μc- Si:H p-layer was obtained.

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30

BERDINSKY, A. S., P. S. ALEGAONKAR, H. C. LEE, J. S. JUNG, J. H. HAN, J. B. YOO, D. FINK, and L. T. CHADDERTON. "GROWTH OF CARBON NANOTUBES IN ETCHED ION TRACKS IN SILICON OXIDE ON SILICON." Nano 02, no. 01 (February 2007): 59–67. http://dx.doi.org/10.1142/s1793292007000386.

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Carbon nanotubes (CNTs) were selectively grown in etched ion tracks in SiO 2 layers on Si . For this sake, Ni -catalyst nanocrystals were initially deposited within the ion tracks by galvanic deposition. The characteristics of plasma-enhanced chemical vapor deposition (PECVD)- and thermal chemical vapor deposition (TCVD)-grown CNTs, such as structural details and length distribution, were investigated. In addition, field emission properties were studied. The analysis revealed that the emerging PECVD-grown CNTs were of cylindrical and/or conical shape and usually had diameters as large as the etched tracks. The exponential length distribution of these CNTs can be well understood by applying a simple defect-growth model. For contrast, many narrow and curled CNTs were found to cluster in spots well separated from each other, after applying TCVD instead of PECVD. The Raman investigations of PECVD-grown CNTs showed that Si – O – C and Si – C phases had formed during the growth of the CNTs. These ion-track-correlated PECVD-grown CNTs open the way for the production of novel 3D nanoelectronic devices based on the TEMPOS concept. These structures are also excellent candidates for experiments on channeling in CNTs. Application as field emitting devices, however, appears unfavorable due to poor mean-field enhancement factors and insufficient stability.

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31

Grootoonk, B., J. Woerdenweber, A. Gordijn, O. Gabriel, and M. Meier. "Monitoring of powder formation via optical emission spectroscopy and self-bias-voltage measurements for high depletion μc-Si:H deposition regimes." Canadian Journal of Physics 92, no. 7/8 (July 2014): 736–39. http://dx.doi.org/10.1139/cjp-2013-0604.

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Microcrystalline silicon fabricated by plasma-enhanced chemical vapour deposition (PECVD) is commonly used as an absorber material in thin-film tandem solar cells. The source gases used in the μc-Si:H PECVD process are silane and hydrogen. One way to further increase the production efficiency of solar modules is to increase the gas utilization during deposition of the silicon absorber layer. In this work this is achieved by reducing the hydrogen flow. These deposition conditions are known to promote powder formation in the plasma, which can be detrimental for the solar cell’s conversion efficiency as well as for the maintenance of the system. Therefore, an easily applicable approach to determine powder formation in-situ during the PECVD process is presented. Both the self-bias-voltage and the ratio of the optical emissions from SiH* to Hβ as function of the gas residence time in the plasma is used to determine the onset of powder formation. Furthermore, a clear link between the precursor gas residence time in the plasma to the onset of powder formation is shown independent of the chosen pressure.

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32

Stradins, Paul, Oliver Kunz, David L. Young, Yanfa Yan, Kim M. Jones, Yueqin Xu, Robert C. Reedy, Howard M. Branz, Armin G. Aberle, and Qi Wang. "Comparative Study of Solid-Phase Crystallization of Amorphous Silicon Deposited by Hot-wire CVD, Plasma-Enhanced CVD, and Electron-Beam Evaporation." MRS Proceedings 989 (2007). http://dx.doi.org/10.1557/proc-0989-a16-04.

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AbstractSolid-phase crystallization (SPC) rates are compared in amorphous silicon films prepared by three different methods: hot-wire chemical vapor deposition (HWCVD), plasma-enhanced chemical vapor deposition (PECVD), and electron-beam physical vapor deposition (e-beam). Random SPC proceeds approximately 5 and 13 times slower in PECVD and e-beam films, respectively, as compared to HWCVD films. Doping accelerates random SPC in e-beam films but has little effect on the SPC rate of HWCVD films. In contrast, the crystalline growth front in solid-phase epitaxy experiments propagates at similar speed in HWCVD, PECVD, and e-beam amorphous Si films. This strongly suggests that the observed large differences in random SPC rates originate from different nucleation rates in these materials while the grain growth rates are relatively similar. The larger grain sizes observed for films that exhibit slower random SPC support this suggestion.

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33

Batey, J., E. Tierney, T. N. Nguyen, J. W. Stasiak, and J. Li. "Low Temperature Plasma Enhanced CVD of ‘Device Quality’ Silicon Dioxide." MRS Proceedings 105 (1987). http://dx.doi.org/10.1557/proc-105-71.

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AbstractAs silicon-based technologies move towards submicron dimensions, vertical and three dimensional structures, the need for reduced thermal processing becomes more evident than ever. Currently, insulator (usually SiO2) growth and deposition contribute significantly to the total thermal budget, and it is clear that this will have to be reduced in future processes. In addition, many other applications require the deposition of high quality dielectrics at very low substrate temperatures, typically ≳ 350°C. Plasma-enhanced chemical vapor deposition (PECVD) is a technique which can be used to deposit insulators at suitably low temperatures, although it tends to produce SiO2 which exhibits poor electrical and physical properties and which forms poor interfaces with semiconductor substrates. Direct exposure to the high energy environment of the plasma is generally thought to be the main reason for this.

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34

Periasamy, Sangeetha, Sasirekha Venkidusamy, Ragavendran Venkatesan, Jeyanthinath Mayandi, Joshua Pearce, Josefine Helene Selj, and Ramakrishnan Veerabahu. "Micro-Raman Scattering of Nanoscale Silicon in Amorphous and Porous Silicon." Zeitschrift für Physikalische Chemie 231, no. 9 (January 1, 2017). http://dx.doi.org/10.1515/zpch-2016-0961.

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Abstract:The size effect of nanoscale silicon in both amorphous and porous silicon was investigated with micro-Raman spectroscopy. Silicon nanostructures in amorphous silicon were deposited on quartz substrates by plasma enhanced chemical vapor deposition (PECVD) with deposition powers of 15, 30 and 50 W. Micro-Raman spectra of the nanostructured silicon show the T

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35

Buršíková, Vilma, Lenka Zajíčková, Pavel Dvořák, Miroslav Valtr, Jiří Buršík, Olga Bláhová, Vratislav Peřina, and Jan Janča. "Influence of Silicon, Oxygen and Nitrogen Admixtures Upon the Properties of Plasma Deposited Amorphous Diamond-Like Carbon Coatings." Journal of Advanced Oxidation Technologies 9, no. 2 (January 1, 2006). http://dx.doi.org/10.1515/jaots-2006-0223.

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AbstractAmorphous diamond-like carbon films (DLC) with various silicon, oxygen and nitrogen content were deposited by plasma enhanced chemical vapor deposition (PECVD) technique. The films were prepared from the mixture of methane and hexamethyldisiloxane (HMDSO) in r.f. capacitively coupled discharges (13.56 MHz). The reactive plasma was investigated by optical emission spectroscopy and capacitive coupled planar probe. A combination of RBS, ERDA, FTIR and XPS methods was used to study the films’ chemical composition and structure. The mechanical properties were studied using a depth sensing indentation technique. The films were mainly composed of C-C, C-H and C-Si bonds. The optimum deposition conditions for the preparation of DLC films, with enhanced thermo-mechanical stability, were determined.

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36

Miri, A. M., S. G. Chamberlain, and A. Nathan. "Effects of Deposition Power and Temperature on the Properties of Heavily Doped Microcrystalline Silicon Films." MRS Proceedings 420 (1996). http://dx.doi.org/10.1557/proc-420-307.

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AbstractWe studied the effect of RF deposition power and temperature on the electrical and structural properties of plasma enhanced chemical vapor deposited (PECVD), heavily doped microcrystalline silicon films (n+μC-Si:H). The film growth process was found to be CVDlike at low powers and PVD-like (Physical Vapor Deposition) at high powers. We show that the film properties strongly depend on the nature of the growth process. We observed that at low temperatures the microcrystalline formation is mainly governed by the presence of hydrogen. This can be improved by increasing the substrate temperature. However, a further increase in substrate temperature tends to reduce hydrogen incorporation into the film and hence decreases the role of hydrogen in the formation of microcrystallites. Resistivities as low as 0.1 Ω.cm were achieved for 500Å thin layers deposited at a relatively low temperature of 220°C and power density of 40mW/cm2.

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37

Devine, R. A. B., and R. L. Pfeffer. "Evidence for Strongly Enhanced Paramagnetic Defect Creation in Low Temperature Pecvd SiO2 Films." MRS Proceedings 165 (1989). http://dx.doi.org/10.1557/proc-165-119.

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AbstractAmorphous SiO2 films have been deposited by plasma enhanced chemical vapor deposition (N2O:SiH4 flow rate ratio of 40:1) then 60Co gamma irradiated. We observe paramagnetic defects similar to oxygen vacancy centers which are created at least 100 times more efficiently in as-deposited oxide than in the same oxide annealed for 1 hr in Ar at 950°C. Positive fixed oxide charge creation in samples irradiated in the unbiased mode has a fractional yield of 0.018 defects per electron-hole pair. No enhancement of the positive fixed oxide charge creation is observed when comparing as-deposited and annealed films suggesting that the paramagnetic and electric defects do not have the same physical origin. Comments are made about the potential hazards of using such deposited oxide near a semiconductor surface where surface inversion may occur.

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38

Collins, R. W., Sangbo Kim, Joohyun Koh, J. S. Burnham, Lihong Jiao, Ing-Shin Chen, and C. R. Wronski. "Advances in the Characterization of Compositionally-graded Layers in Amorphous Semiconductor Solar Cells by Real Time Spectroellipsometry." MRS Proceedings 420 (1996). http://dx.doi.org/10.1557/proc-420-443.

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AbstractWe have developed a real time spectroellipsometry data analysis procedure that allows us to characterize compositionally- graded amorphous semiconductor alloy thin films prepared by plasma-enhanced chemical vapor deposition (PECVD). As an example, we have applied the analysis to obtain the depth-profile of the optical gap and alloy composition with ≤15 Å resolution for a hydrogenated amorphous silicon-carbon alloy (a-Si1−xCx:H) film prepared by continuously varying the gas flow ratio z=[CH4]/{[CH4]+[SiH4]} in the PECVD process. The graded layer has been incorporated at the p/i interface of widegap a-Si1−xCx:H (x∼0.05) p-i-n solar cells, and consistent improvements in open-circuit voltage have been demonstrated. The importance of the graded-layer characterization is the ability to relate improvements in device performance directly to the physical properties of the interface layer, rather to the deposition parameters with which they were prepared.

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39

Boas, C. R. S. V., B. Focassio, E. Marinho, D. G. Larrude, M. C. Salvadori, C. Rocha Leão, and D. J. dos Santos. "Characterization of nitrogen doped graphene bilayers synthesized by fast, low temperature microwave plasma-enhanced chemical vapour deposition." Scientific Reports 9, no. 1 (September 23, 2019). http://dx.doi.org/10.1038/s41598-019-49900-9.

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Abstract New techniques to manipulate the electronic properties of few layer 2D materials, unveiling new physical phenomena as well as possibilities for new device applications have brought renewed interest to these systems. Therefore, the quest for reproducible methods for the large scale synthesis, as well as the manipulation, characterization and deeper understanding of these structures is a very active field of research. We here report the production of nitrogen doped bilayer graphene in a fast single step (2.5 minutes), at reduced temperatures (760 °C) using microwave plasma-enhanced chemical vapor deposition (MW-PECVD). Raman spectroscopy confirmed that nitrogen-doped bilayer structures were produced by this method. XPS analysis showed that we achieved control of the concentration of nitrogen dopants incorporated into the final samples. We have performed state of the art parameter-free simulations to investigate the cause of an unexpected splitting of the XPS signal as the concentration of nitrogen defects increased. We show that this splitting is due to the formation of interlayer bonds mediated by nitrogen defects on the layers of the material. The occurrence of these bonds may result in very specific electronic and mechanical properties of the bilayer structures.

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40

Mallikarjunan, Anupama, Laura M. Matz, Andrew D. Johnson, Raymond N. Vrtis, Manchao Xiao, Mark O. Neill, and Bing Han. "Precursor design and engineering for low-temperature deposition of gate dielectrics for thin film transistors." MRS Proceedings 1287 (2011). http://dx.doi.org/10.1557/opl.2011.1432.

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ABSTRACTThe electrical and physical quality of gate and passivation dielectrics significantly impacts the device performance of thin film transistors (TFTs). The passivation dielectric also needs to act as a barrier to protect the TFT device. As low temperature TFT processing becomes a requirement for novel applications and plastic substrates, there is a need for materials innovation that enables high quality plasma enhanced chemical vapor deposition (PECVD) gate dielectric deposition. In this context, this paper discusses structure-property relationships and strategies for precursor development in silicon nitride, silicon oxycarbide (SiOC) and silicon oxide films. Experiments with passivation SiOC films demonstrate the benefit of a superior precursor (LkB-500) and standard process optimization to enable lower temperature depositions. For gate SiO2 deposition (that are used with polysilicon TFTs for example), organosilicon precursors containing different types and amounts of Si, C, O and H bonding were experimentally compared to the industry standard TEOS (tetraethoxysilane) at different process conditions and temperatures. Major differences were identified in film quality especially wet etch rate or WER (correlating to film density) and dielectric constant (k) values (correlating to moisture absorption). Gate quality SiO2 films can be deposited by choosing precursors that can minimize residual Si-OH groups and enable higher density stable moisture-free films. For e.g., the optimized precursor AP-LTO® 770 is clearly better than TEOS for low temperature PECVD depositions based on density, WER, k charge density (measured by flatband voltage or Vfb); and leakage and breakdown voltage (Vbd) measurements. The design and development of such novel precursors is a key factor to successfully enable manufacturing of advanced low temperature processed devices.

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Moinpour, Mansour, Ken Mack, Johnny Cham, Farhad Moghadam, and Byron Williams. "Characterization of PECVD SixOyNz:H Films and its Correlation to Device Performance and Reliability." MRS Proceedings 338 (1994). http://dx.doi.org/10.1557/proc-338-75.

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ABSTRACTFor integrated circuits, the integrity and film quality of the final passivation layer plays an important role in the device performance and reliability. Hydrogenated amorphous silicon oxynitride (α-SixNyOz:H) films deposited by plasma enhanced chemical vapor deposition (PECVD) have been extensively used for final device passivation applications. In this paper, a detailed characterization of PECVD oxynitride process for 200 mm Si wafer processing is presented. Silicon oxynitride of various compositions were deposited by changing the amounts of silane, ammonia, nitrogen and nitrous oxide in the reactant gas stream. Ultraviolet/Visible (UV/VIS) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Rutherford backscattering spectrometry (RBS), and refractive index measurements were used to examine the variation in physical, optical and electrical properties. A correlation is observed between the oxynitride film composition, mainly N-H/Si-H ratio, and UV transmissivity (UV %T) which is of particular interest for memory applications. Effects of oxynitride film quality on e-test parameters and device performance are discussed.

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O‘Brien, M. L., S. Pejdo, and R. J. Nemanich. "Morphology Of Silicon Oxides On Silicon Carbide." MRS Proceedings 483 (1997). http://dx.doi.org/10.1557/proc-483-437.

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AbstractThe development of high power devices based on silicon carbide requires a more complete understanding of the oxide formation process and interface characteristics. By using an integrated UHV system, samples were cleaned and oxides deposited in situ. The approach of the oxide formation process was to form the initial insulator, a few angstroms thick, and then deposit an oxide. Various deposition techniques are used in the oxide growth process; both thermal and plasma enhanced chemical vapor deposition were employed with two different precursors (oxygen and nitrous oxide), and the results were compared with thermal oxidation. The morphology of each of the deposited oxides was compared to the bare substrate and the thermal oxide wafers. This study focuses on the morphology of the different deposition processes using AFM. Examination of the morphology of the initial insulator growth process and the oxide deposition process gives insight into the physical characteristics of the silicon dioxide deposited on silicon carbide. The RMS values of the initial insulator formation and the control wafers are 0.93 and 0.95 nm respectively. Meanwhile, the RMS values for PECVD (200–400°C) and thermal CVD (400–600°C for oxygen-silane and 800–1000°C for nitrous oxide-silane) range from 1.43 to 1.93 nm.

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Major, Roman, Maciej Gawlikowski, Hanna Plutecka, Marcin Surmiak, Marcin Kot, Marcin Dyner, Juergen M. Lackner, and Boguslaw Major. "Biocompatibility testing of composite biomaterial designed for a new petal valve construction for pulsatile ventricular assist device." Journal of Materials Science: Materials in Medicine 32, no. 9 (August 30, 2021). http://dx.doi.org/10.1007/s10856-021-06576-w.

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AbstractThis paper presents the results of biocompatibility testing performed on several biomaterial variants for manufacturing a newly designed petal valve intended for use in a pulsatile ventricular assist device or blood pump. Both physical vapor deposition (PVD) and plasma-enhanced chemical vapor deposition (PECVD) were used to coat titanium-based substrates with hydrogenated tetrahedral amorphous carbon (ta-C:H) or amorphous hydrogenated carbon (a-C:H and a-C:H, N). Experiments were carried out using whole human blood under arterial shear stress conditions in a cone-plate analyzer (ap. 1800 1/s). In most cases, tested coatings showed good or very good haemocompatibility. Type a-C:H, N coating proved to be superior in terms of activation, risk of aggregation, and the effects of generating microparticles of apoptotic origin, and also demonstrated excellent mechanical properties. Therefore, a-C:H, N coatings were selected for further in vivo studies. In vivo animal studies were carried out according to the ISO 10993 standard. Intradermal reactivity was assessed in three rabbits and sub-acute toxicity and local effects after implantation were examined in 12 rabbits. Based on postmortem examination, no organ failure or wound tissue damage occurred during the required period of observation. In summary, our investigations demonstrated high biocompatibility of the biomaterials in relation to thrombogenicity, toxicity, and wound healing. Prototypes of the petal valves were manufactured and mounted on the pulsatile ventricular assist device. Hydrodynamic features and impact on red blood cells (hemolysis) as well as coagulation (systemic thrombogenicity) were assessed in whole blood.

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44

Okita, Atsushi, Yoshiyuki Suda, Masayuki Maekawa, Junichi Takayama, Akinori Oda, Hirotake Sugawara, and Yosuke Sakai. "Plasma-enhanced chemical vapor deposition of carbon nanotubes using alcohol vapor." MRS Proceedings 1057 (2007). http://dx.doi.org/10.1557/proc-1057-ii05-10.

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ABSTRACTWe have successfully grown carbon nanotubes (CNTs) by alcohol plasma-enhanced chemical vapor deposition (PECVD). When 0.01 wt% ferrocene was added to alcohol, vertically-aligned CNTs could be grown using RF (= 13.56 MHz) plasma at 650°C. In contrast, no CNTs were obtained by pure alcohol PECVD. To understand the plasma properties for CNT growth, especially plasma species containing a gas phase of alcohol plasma, we analyzed the plasma using optical emission spectroscopy (OES) and quadrupole mass spectrometry (QMS). From the OES measurement, one could identify the emission peaks from the excitation states of CHO, CO, C2, O2, H, CH+, and H2O+, while the QMS measurement also showed the existence of CO, H2O, and CxHy (x≥2, y≥2). It is considered that such plasma species affect CNT growth by changing the oxidation state of the catalyst or by adjusting the amount of precursor species in the plasma. Comparing this PECVD experiment with thermal alcohol CVD (without plasma), only PECVD can be used to grow CNTs under the reported experimental conditions. It is considered that thermal alcohol CVD requires more energy to grow CNTs because 650°C is a little lower than the temperature required for CNT growth. These results indicate that in alcohol plasma, the active species produced by decomposition and recombination reactions have a possibility to promote/suppress CNT growth depending on the process conditions.

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45

Lucovsky, G., D. V. Tsu, and R. J. Markunas. "Deposition of Dielectric Films by Remote Plasma Enhanced CVD." MRS Proceedings 68 (1986). http://dx.doi.org/10.1557/proc-68-323.

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AbstractWe describe a plasma enhanced chemical vapor deposition process (PECVD) developed for the low temperature deposition of thin films of silicon oxides, nitrides and oxynitrides.The process, designated as remote PECVD (RPECVD), differs from conventional PECVD in two ways; (a) not all of the process gases are subjected to plasma excitation; and (b) the deposition is done outside of the plasma region.We include an empirical model of the deposition process chemistry and discuss the use of infrared spectroscopy (IR) and Auger electron spectroscopy (AES) to characterize the local atomic structure of the deposited films.

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46

Ferreira, G. M., A. S. Ferlauto, J. M. Pearce, C. R. Wronski, C. Ross, and R. W. Collins. "Comparison of Phase Diagrams for vhf and rf Plasma-Enhanced Chemical Vapor Deposition of Si:H Films." MRS Proceedings 808 (2004). http://dx.doi.org/10.1557/proc-808-a5.2.

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ABSTRACTDeposition phase diagrams are convenient for categorizing the evolution of the surface microstructure and phase with accumulated thickness for hydrogenated silicon (Si:H) films during plasma-enhanced chemical vapor deposition (PECVD). They can also be used to assess the electronic quality and device suitability of Si:H, based on previous correlations. In this study, phase diagrams have been applied in a comparison of Si:H PECVD using two different plasma excitation frequencies (rf: 13.56 MHz; and vhf: 60 MHz). Smooth crystalline Si (c-Si) wafer substrates have been used to obtain the surface roughness evolution with maximum sensitivity in the amorphous silicon (a-Si:H) growth regime. This study has shown that under all explored conditions of plasma power, frequency, and gas pressure, yielding deposition rates of 0.5-20 Å/s, a-Si:H exhibits improved microstructural characteristics with increasing H2-to-SiH4 flow ratio R right up to the amorphous-to-(mixed-phase microcrystalline) [a→(a+μc)] boundary of the phase diagram. For depositions at R values much lower than the a→(a+μc) transition for a thick film, vhf PECVD can provide a significant improvement in microstructural evolution over rf PECVD, for a given deposition rate. For optimum R just below the a→(a+μc) transition, however, vhf and rf a-Si:H films exhibit remarkably similar structural evolution for a given rate.

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47

Tsu, D. V., G. N. Parsons, G. Lucovsky, and M. W. Watkins. "Control of Bonded SiH in Silicon Oxides Deposited by Remote Plasma Enhanced CVD." MRS Proceedings 105 (1987). http://dx.doi.org/10.1557/proc-105-73.

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AbstractThis paper describes Optical Emission Spectrocopy (OES) and Mass Spectrometry (MS) studies of the plasma region in the Remote Plasma Enhanced Chemical Vapor Deposition (PECVD) of amorphous hydrogenated silicon (a-Si:H) and silicon oxide thin films. In Remote PECVD, only the O2/He mixture is plasma excited, silane is introduced into the deposition chamber well below the plasma region. Deposition of films has been studied over a wide range of relative He and O2flows, between 100% He and 100% O2. The incorporation of SiH in the oxides derives from the same mechanism as the deposition of a-Si:H, i.e., a metastable He induced fragmentation of silane.

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48

Lucovsky, G., P. D. Richard, D. V. Tsu, and R. J. Markunas. "Deposition of Thin Insulating films by Plasma Enhanced CVD." MRS Proceedings 54 (1985). http://dx.doi.org/10.1557/proc-54-529.

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ABSTRACTWe discuss a new low temperature process for the deposition of electronic quality thin films of silicon oxide and nitride. In contrast to conventional plasma enhanced chemical vapor deposition [PECVD], this process involves the remote excitation of one of the gas reactants followed by the extraction of the active species out of the plasma region where they react to generate precursor molecules. The precursors undergo a CVD reaction at a heated substrate to form the desired thin film. The process is called remote PECVD [RPECVD]. Insulators produced in this way show significant reductions in the incorporation of impurity groups such as SiH and SiOH relative to films grown by the PECVD process at the same substrate temperatures.

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Choi, S. W., K. J. Bachmann, and G. Lucovsky. "Deposition of GaN by Remote Plasma-Enhanced Chemical-Vapor Deposition (Remote PECVD)." MRS Proceedings 204 (1990). http://dx.doi.org/10.1557/proc-204-195.

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Abstract:

ABSTRACTFilms of GaN have been grown on silicon by remote plasma-enhanced chemical-vapor deposition using trimethyl gallium and ammonia. The ammonia is rf plasma excited along with He, and the trimethyl gallium is introduced downstream from the plasma generation zone. The activation energy for the growth of GaN is 0.95±0.05 eV. This is tentatively assigned to the activation of NH groups, extracted from the plasma as primary precursors for the surface reaction with trimethyl gallium (TMG), or adsorbed fragments of this molecule. At high He flow rates, an abrupt increase in the growth rate is observed corresponding to a change in the reaction mechanism which is attributed to the formation of atomic nitrogen.

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Hoek, W. G. M. Van Den. "Characterization of Plasma-Enhanced Chemical Vapour Deposition of Silicon-Oxynitride." MRS Proceedings 68 (1986). http://dx.doi.org/10.1557/proc-68-335.

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Abstract:

AbstractThe plasma-enhanced chemical vapour deposition (PECVD) of siliconoxynitride from silane, ammonia and nitrous oxide was studied using an ASM vertical parallel plate reactor.Films varying from PECVD oxide (refractive index no1.50) to PECVD nitride (n=2.00) were analyzed using ellipsometry, UV-visible reflection spectroscopy, Fourier-transform infrared transmission spectroscopy (FTIR), nuclear reaction analysis (NRA), Rutherford backscattering (RBS) and electron spectoscopy for chemical analysis (ESCA).Stress measurements were performed using a Fizeau interferometer.

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Journal articles on the topic 'Plasma Enhanced Physical Vapor Deposition (PEPVD)'

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