Download or read book Deposition of Device Quality Low Hydrogen Content Hydrogenated Amorphous Silicon at High Deposition Rates with Increased Stability Using the Hot Wire Filament Technique written by and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deposition of Device Quality Low Hydrogen Content Hydrogenated Amorphous Silicon at High Deposition Rates with Increased Stability Using the Hot Wire Filament Technique written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A method or producing hydrogenated amorphous silicon on a substrate, comprising the steps of: positioning the substrate in a deposition chamber at a distance of about 0.5 to 3.0 cm from a heatable filament in the deposition chamber; maintaining a pressure in said deposition chamber in the range of about 10 to 100 millitorr and pressure times substrate-filament spacing in the range of about 10 to 100 millitorr-cm, heating the filament to a temperature in the range of about 1,500 to 2,000.degree. C., and heating the substrate to a surface temperature in the range of about 280 to 475.degree. C.; and flowing silicohydride gas into the deposition chamber with said heated filament, decomposing said silicohydride gas into silicon and hydrogen atomic species and allowing products of gas reactions between said atomic species and the silicohydride gas to migrate to and deposit on said substrate while adjusting and maintaining said pressure times substrate-filament spacing in said deposition chamber at a value in said 10 to 100 millitorr range to produce statistically about 3 to 50 atomic collisions between the silicon and hydrogen atomic species migrating to said substrate and undecomposed molecules of the silane or other silicohydride gas in the deposition chamber.
Download or read book Official Gazette of the United States Patent and Trademark Office written by United States. Patent and Trademark Office and published by . This book was released on 2000 with total page 1148 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deposition of Device Quality Low Hydrogen Content Hydrogenated Amorphous Silicon at High Deposition Rates written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Amorphous Silicon Technology 1996 Volume 420 written by Michael Hack and published by . This book was released on 1996-12-31 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book from the highly successful series on amorphous-silicon science and devices reflects the increasing range of applications for a-Si technology. Advances in solar cells incorporating microcrystalline silicon absorber layers are discussed, and a new manufacturing facility for amorphous-silicon-based tandem solar cells is highlighted. Progress towards realizing both higher resolution and improved visibility in active-matrix liquid crystal displays is featured. And while work on raising the deposition rate for amorphous-silicon transistors is also outlined, it is expected that advances in devices and manufacturing will be accelerated when several fundamental puzzles regarding amorphous silicon's structure and optoelectronic properties are resolved. Topics include: solar cells; thin-film transistors and flat-panel displays; sensors, detectors and novel devices; device physics; deposition technologies; studies of growth processes; hydrogen and structure a-Si:H; defects and equilibration in a-Si:H; fundamental issues in defect processes; transport and recombination processes; thin films for photovoltaic and related device applications.
Download or read book Amorphous Silicon Technology written by and published by . This book was released on 1996 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deposition of Device Quality Low H Content Amorphous Silicon Films written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A high quality, low hydrogen content, hydrogenated amorphous silicon (a-Si:H) film is deposited by passing a stream of silane gas (SiH.sub. 4) over a high temperature, 2000.degree. C., tungsten (W) filament in the proximity of a high temperature, 400.degree. C., substrate within a low pressure, 8 mTorr, deposition chamber. The silane gas is decomposed into atomic hydrogen and silicon, which in turn collides preferably not more than 20-30 times before being deposited on the hot substrate. The hydrogenated amorphous silicon films thus produced have only about one atomic percent hydrogen, yet have device quality electrical, chemical, and structural properties, despite this lowered hydrogen content.
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book JJAP written by and published by . This book was released on 2006 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Japanese Journal of Applied Physics written by and published by . This book was released on 2007 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flat Panel Display Materials II Volume 424 written by Miltiadis K. Hatalis and published by . This book was released on 1997-02-12 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proceedings of a symposium held April 1996, in San Francisco, California. The field is experiencing a rapid growth which currently is expanding from portable computer applications to include display applications for desktop computers and a wide array of consumer and industrial products. Seventy-six contributions are divided into six sections covering amorphous silicon thin-film transistor materials, polycrystalline silicon thin-film transistor materials, liquid crystal display materials, transparent conducting oxides, field emission display materials, and other emissive display materials. Annotation copyrighted by Book News, Inc., Portland, OR
Download or read book Flat Panel Display Materials written by and published by . This book was released on 1996 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Deposition of Device Quality Low H Content Amorphous Silicon Films written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Photovoltaic Silicon written by Deren Yang and published by Springer. This book was released on 2019-11-28 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The utilization of sun light is one of the hottest topics in sustainable energy research. To efficiently convert sun power into a reliable energy – electricity – for consumption and storage, silicon and its derivatives have been widely studied and applied in solar cell systems. This handbook covers the photovoltaics of silicon materials and devices, providing a comprehensive summary of the state of the art of photovoltaic silicon sciences and technologies. This work is divided into various areas including but not limited to fundamental principles, design methodologies, wafering techniques/fabrications, characterizations, applications, current research trends and challenges. It offers the most updated and self-explanatory reference to all levels of students and acts as a quick reference to the experts from the fields of chemistry, material science, physics, chemical engineering, electrical engineering, solar energy, etc..
Download or read book Optimization of the Reactive Magnetron Sputter Deposition and Studies of Hydrogen Diffusion in Hydrogenated Amorphous Silicon Based Materials written by Yuehai Harry Liang and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The applications of hydrogenated amorphous silicon in photovoltaic devices have been hindered due to two key problems: the light-induced metastable defect creation and poor doping. To improve these properties, I have chosen the reactive magnetron sputtering method for the growth of a-Si:H and its doped alloys. The advantages of this technique are the independent control of hydrogen incorporation via the pressure of H$\sb2$ injected into the plasma, and the energetic nature of the deposition species. The effects of growth parameters on the electrical and microstructural properties have been studied, and the films appear to be optimized. Earlier studies indicated that the mid-gap defect density of high quality a-Si:H increases from 10$\sp{15}$ cm$\sp{-3}$, and saturates at 9 x 10$\rm\sp{16}\ cm\sp{-3}$ after intense light exposure. Using reactive magnetron sputtering, I have achieved a very stable high quality a-Si:H: the saturated defect density reaches the lowest value (2$-$3 x 10$\rm\sp{16} cm\sp{-3}$) reported so far in the literature. This significant improvement of the stability could result in a high stabilized solar cell efficiency. For p$\sp+$ a-Si,C:H, films with much lower thermal activation energy (0.28-0.33 eV) have been obtained, compared with films grown by plasma enhanced chemical vapor deposition (0.4 eV). Microstructural investigation shows that the microvoid contents in these films are much less than that of high quality boron doped a-Si,C:H prepared by plasma enhanced chemical vapor deposition. I attribute the significant improvements of stability and doping efficiency of the sputtered amorphous silicon and its alloys to the better amorphous network. Hydrogen diffusion in a-Si:H has been associated with the metastable defect creation and annealing. A systematic study of hydrogen diffusion kinetics in sputtered a-Si:H is carried out for the first time. The independent control of hydrogen incorporation allows me to study explicitly the effect of hydrogen content on hydrogen diffusion kinetics. I have found that H diffusion coefficient varies strongly with the hydrogen concentration in a-Si:H film. The H diffusion coefficient is thermally activated, with the activation energy decreases from 1.6 to 1.0 eV as the hydrogen concentration increases from 1.2-12 at.%. For film with higher hydrogen content ($\sim$18 at.%), the H diffusion profile shows an exponential decay. This observation indicates that the diffusion process is deep trapping limited. Based on the experimental results, I have proposed a revised H density of states model to account for the strongly concentration dependent diffusion behavior. As the H chemical potential shifts closer to the transport level with the increase of hydrogen content, the diffusion activation energy decreases and the diffusion coefficient increases.
Download or read book High Growth Rate Deposition of Hydrogenated Amorphous Silicon germanium Films and Devices Using ECR PECVD written by Yong Liu and published by . This book was released on 2002 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogenated amorphous silicon germanium (a-SiGe:H) films and devices have been extensively studied because of the tunable band gap for matching the solar spectrum and mature the fabrication techniques. a-SiGe:H thin film solar cells have great potential for commercial manufacture because of very low cost and adaptability to large scale manufacturing. Although it has been demonstrated that a-SiGe:H thin films and devices with good quality can be produced successfully, some issues regarding growth chemistry have remained yet unexplored, such as the hydrogen and inert gas dilution, bombardment effect, and chemical annealing, to name a few. The alloying of the SiGe introduces above an order-of-magnitude higher defect density, which degrades the performance of the a-SiGe:H thin film solar cells. This degradation becomes worse when high growth-rate deposition is required. The work presented here uses the Electron-Cyclotron-Resonance Plasma-Enhanced Chemical Vapor Deposition (ECR-PECVD) technique to fabricate a-SiGe:H films and devices with high growth rates. Helium gas, together with small amount of H2, was used as the plasma species. Thickness, optical band gap, conductivity, Urbach energy, mobility-lifetime product, and quantum efficiency were characterized during the process of pursuing good materials. High-quality material was successfully fabricated with the ECR-PECVD technique at high growth rates. The device we made with 1.47 eV band gap has a fill factor of 64.5%. With the graded band gap and graded doping techniques, 70% fill factor was achieved when the band gap was graded from 1.75 to 1.47 eV. We also got 68% fill factor with the band gap graded form 1.75 to 1.38 eV.
Download or read book High Growth Rate Deposition of Hydrogenated Amorphous Silicon Germanium Films and Devices Using ECR PECVD written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydrogenated amorphous silicon germanium films (a-SiGe:H) and devices have been extensively studied because of the tunable band gap for matching the solar spectrum and mature the fabrication techniques. a-SiGe:H thin film solar cells have great potential for commercial manufacture because of very low cost and adaptability to large-scale manufacturing. Although it has been demonstrated that a-SiGe:H thin films and devices with good quality can be produced successfully, some issues regarding growth chemistry have remained yet unexplored, such as the hydrogen and inert-gas dilution, bombardment effect, and chemical annealing, to name a few. The alloying of the SiGe introduces above an order-of-magnitude higher defect density, which degrades the performance of the a-SiGe:H thin film solar cells. This degradation becomes worse when high growth-rate deposition is required. Preferential attachment of hydrogen to silicon, clustering of Ge and Si, and columnar structure and buried dihydride radicals make the film intolerably bad. The work presented here uses the Electron-Cyclotron-Resonance Plasma-Enhanced Chemical Vapor Deposition (ECR-PECVD) technique to fabricate a-SiGe:H films and devices with high growth rates. Helium gas, together with a small amount of H[sub 2], was used as the plasma species. Thickness, optical band gap, conductivity, Urbach energy, mobility-lifetime product, I-V curve, and quantum efficiency were characterized during the process of pursuing good materials. The microstructure of the a-(Si, Ge):H material was probed by Fourier-Transform Infrared spectroscopy. They found that the advantages of using helium as the main plasma species are: (1) high growth rate--the energetic helium ions break the reactive gas more efficiently than hydrogen ions; (2) homogeneous growth--heavy helium ions impinging on the surface promote the surface mobility of the reactive radicals, so that heteroepitaxy growth as clustering of Ge and Si, columnar structure are reduced; (3) surface hydrogen removal--heavier and more energetic helium ions break the Si-H much easier than hydrogen ions. The preferential attachment of Si-H to Ge-H is reduced. They also found that with the small amount of hydrogen put into the plasma, the superior properties of a-(Si, Ge):H made from pure hydrogen dilution plasma were still maintained. These hydrogen ions help to remove the subsurface weakly bonded hydrogen and buried hydrogen. They also help to passivate the Ge-dangling bond.
