Download or read book Structure of Amorphous Silicon and Germanium Alloy Films written by and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of the research is to improve the understanding at the microscopic level of amorphous silicon and germanium film structures deposited under various methods. The work is to correlate and theoretically analyze, nuclear magnetic resonance, NMR, ESR, electron spin resonance, and other measurements. The alloys of concern include those obtained by adding dopants to hydrogenated silicon and germanium. The work has been directed to continue deuteron magnetic resonance DMR studies and to pay particulate attention to those structural features which may correlate with the photoelectronic properties of the material. The 1990 (DMR) accomplishments have included correlation of inhomogeneous nuclear spin relaxation with photovoltaic quality. In a second project, a structural rearrangement of atoms has been demonstrated to be associated with the light-induced metastability in a-Si:D, H films. A third approach has employed proton-deuteron coupled spin dynamics to examine hydrogen and deuterium motions in quality films of a-Si:H; a-Si:P, H; and a-Si:D, H. The B- P-doped films show a significantly enhanced hydrogen mobility above 200 K. We also have performed a number of detailed calculations on the effects coordination and strain on the deep electronic states rising from B and P dopants in a-Si as well as the band tail states in the gap of a-Si arising from strained bonds. This work gives a rather complete picture of the effects on the gap states of strain and dopants in the absence of H and for a given configuration of the a-Si network. We conclude that the methods that we have developed over the past three years are capable of describing many of the effects of strained bonds, especially their effect on dopants. 25 refs., 11 figs., 3 tabs.
Download or read book Structure of Amorphous Silicon and Germanium Alloy Films written by R. E. Norberg and published by . This book was released on 1991 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure of Amorphous Silicon and Germanium Alloy Films written by R. E. Norberg and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure of Amorphous Silicon and Germanium Alloy Films written by and published by . This book was released on 1991 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary objective of the research is to improve the understanding at the microscopic level of amorphous silicon and germanium film structures deposited under various methods. The work is to correlate and theoretically analyze, nuclear magnetic resonance, NMR, ESR, electron spin resonance, and other measurements. The alloys of concern include those obtained by adding dopants to hydrogenated silicon and germanium. The work has been directed to continue deuteron magnetic resonance DMR studies and to pay particulate attention to those structural features which may correlate with the photoelectronic properties of the material. The 1990 (DMR) accomplishments have included correlation of inhomogeneous nuclear spin relaxation with photovoltaic quality. In a second project, a structural rearrangement of atoms has been demonstrated to be associated with the light-induced metastability in a-Si:D, H films. A third approach has employed proton-deuteron coupled spin dynamics to examine hydrogen and deuterium motions in quality films of a-Si:H; a-Si:P, H; and a-Si:D, H. The B- P-doped films show a significantly enhanced hydrogen mobility above 200 K. We also have performed a number of detailed calculations on the effects coordination and strain on the deep electronic states rising from B and P dopants in a-Si as well as the band tail states in the gap of a-Si arising from strained bonds. This work gives a rather complete picture of the effects on the gap states of strain and dopants in the absence of H and for a given configuration of the a-Si network. We conclude that the methods that we have developed over the past three years are capable of describing many of the effects of strained bonds, especially their effect on dopants. 25 refs., 11 figs., 3 tabs.
Download or read book Electron Drift Mobilities in Amorphous Silicon germanium Alloy Films written by Jorge Luis Garcia-Colevatti and published by . This book was released on 1982 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure of Amorphous Silicon Alloy Films written by R. E. Norberg and published by . This book was released on 1988 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth Mechanisms and Characterization of Hydrogenated Amorphous silicon alloy Films Annual Subcontract Report 14 February 1992 13 February 1993 written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes work performed to better understand the atomic-scale structure of glow-discharge-produced a-Si:H, a Ge:H, and a-Si:Ge:H films; its effect on film quality; and its dependence on deposition discharge conditions. Hydrogenated a- Si films are deposited from a silane rf discharge onto atomically flat crystal Si and GaAs substrates. The substrates are then transferred in vacuum to a scanning tunneling microscope, where the atomic-scale surface morphology is measured. The films were deposited at T[sub s] = 30[degree]C and 250[degree]C from a silane rf glow discharge using device-quality deposition conditions of 2.66 Pa (0.5 Torr) silane pressure, 1.7 [Angstrom]/s deposition rate, and small power/flow; IR absorption, [sigma][sub L], and [sigma][sub D] indicate high-quality intrinsic films. From the thickness dependence of the surface morphology, we determined that the films initially conform smoothly to an atomically flat Si or GaAs substrate, but as the thickness increases the roughness steadily increases to approximately 10% of the length of the scanned region. The surface of 100-400-nm-thick films is highly inhomogeneous, with steep hills and canyons in some areas and large atomically smooth regions in others. These unexpectedly large surface irregularities indicate severe and often connected void structures in the growing film, as well as relatively limited-range surface diffusion of the incorporating SiH[sub 3] radicals. On the other hand, large areas of atomically flat surface were occasionally found, indicating the possibility of growing a homogeneous and compact amorphous film if appropriate growth conditions could be discovered.
Download or read book Structure of Amorphous Silicon Alloy Films written by R. E. Norberg and published by . This book was released on 1989 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advanced Transmission Electron Microscopy written by Francis Leonard Deepak and published by Springer. This book was released on 2015-06-05 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book highlights the current understanding of materials in the context of new and continuously emerging techniques in the field of electron microscopy. The authors present applications of electron microscopic techniques in characterizing various well-known & new nanomaterials. The applications described include both inorganic nanomaterials as well as organic nanomaterials.
Download or read book Amorphous Hydrogenated Silicon germanium Alloy Thin Film written by Ronald Alan Rudder and published by . This book was released on 1985 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Growth Mechanisms and Characterization of Hydrogenated Amorphous silicon alloy Films Final Subcontract Report 15 February 1991 14 April 1994 written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes work performed to better understand the atomic-scale structure of glow-discharge-produced a-Si:H, a-Ge:H, and a-Si:Ge:H films; its effect on film quality; and its dependence on deposition discharge conditions. Hydrogenated a-Si films are from a silane rf discharge onto atomically flat crystal Si and GaAs substrates. The substrates are then transferred in a scanning tunneling microscope, where the atomic-scale surface morphology is measured. The films were deposited using device-quality deposition conditions; IR absorption, [sigma][sub L], and [sigma][sub D] indicate high-quality intrinsic films. From the thickness dependence of the surface morphology, we determined that the films initially conform smoothly to an atomically flat Si or GaAs substrate, but as the thickness increases the roughness steadily increases to approximately 10% of the length of the scanned region. The surface of 100--400-nm-thick films is highly inhomogeneous, with steep hills and canyons in some areas and large atomically smooth regions in others. These unexpectedly large surface irregularities indicate severe and often connected void structures in the growing film, as well as relatively limited-range surface diffusion of the incorporating SiH[sub 3] radicals. On the other hand, large atomically flat surface were occasionally found, indicating the possibility of growing a homogeneous and compact amorphous film if appropriate growth conditions could be discovered.
Download or read book Structure of Amorphous Silicon Alloy Films written by R. E. Norberg and published by . This book was released on 1988 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Hydrogenated Amorphous Silicon I written by J.D. Joannopoulos and published by Springer. This book was released on 1984 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by numerous experts
Download or read book Structure of Amorphous Silicon Alloy Films written by R. E. Norberg and published by . This book was released on 1989 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book SERI Photovoltaic Advanced Research and Development Bibliography 1982 1985 written by and published by . This book was released on 1986 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1995 with total page 782 pages. Available in PDF, EPUB and Kindle. Book excerpt:
