Download or read book The Time Evolution of the Density of States in Tritiated Hydrogenated Amorphous Silicon written by Stefan Dan Costea and published by . This book was released on 2007 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Density of States in Hydrogenated and Tritiated Amorphous Silicon Thin Films Obtained Using the Constant Photocurrent Method microform written by Simone Pisana and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2004 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: The constant photocurrent method (CPM) was implemented to determine the density of states in amorphous silicon below the Fermi level. Hydrogenated (a-Si:H) and tritiated (a-Si:H:T) amorphous silicon thin films, grown using the DC saddle-field deposition system, where analyzed with CPM. Tritium incorporated in amorphous silicon samples increases the defect state density over time. The results showed an exponential valence band tail and a peak of doubly occupied dangling bonds (D- ) positioned 1.24 eV below the conduction band. The defects in a-Si:H:T were monitored in time showing an increase of defect concentration of about two orders of magnitude. This trend evolved following the theoretical decay of tritium. The a-Si:H samples featured a valence band tail and a peak of singly occupied dangling bonds (D0). A halogen lamp was used to age the samples inducing the Staebler-Wronski effect. Upon illumination the defect density increased by one order of magnitude before saturating.
Download or read book Diffusion and Defect Data written by and published by . This book was released on 2000 with total page 962 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Density of Gap States in Hydrogenated Amorphous Silicon written by Eddy Yahya and published by . This book was released on 1984 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Density of Gap States in Hydrogenated Sputtered Amorphous Silicon written by Ian Gordon Gibb and published by . This book was released on 1983 with total page 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 Measurements of the Density of Localized States in Hydrogenated Amorphous Silicon by Capacitance and Conductance Methods written by David Charles Cousins and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 924 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of the Implantation of Oxygen Nitrogen and Carbon Impurities on the Density of States in the Mobility Gap of Hydrogenated Amorphous Silicon written by Carol Elizabeth Michelson and published by . This book was released on 1988 with total page 216 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 1986 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Hydrogenated Amorphous Silicon II written by J.D. Joannopoulos and published by Springer. This book was released on 1984-03-01 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: With contributions by numerous experts
Download or read book The Use of the Space charge limited Current Method to Measure the Density of States of Hydrogenated Amorphous Silicon written by Reza Meh and published by . This book was released on 1991 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The physics of hydrogenated amorphous silicon written by John D. Joannopoulos and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Physics of Hydrogenated Amorphous Silicon II written by and published by . This book was released on 1983 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Specific Heat of Pure and Hydrogenated Amorphous Silicon written by Daniel Robert Queen and published by . This book was released on 2011 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: At low temperature, amorphous materials have low energy excitations that result in a heat capacity that is in excess of the Debye heat capacity calculated from the sound velocity. These excitations are ubiquitous to the glassy state and occur with roughly the same density for all glasses. The specific heat has a linear temperature dependence below 1K that has been described by the phenomenological two-level systems (TLS) model in addition to a T3 temperature dependence which is in excess of the T3 Debye specific heat. It is still unknown what exact mechanism gives rise to the TLS but it is assumed that groups of atoms have configurations that are close in energy and, at low temperature, these atoms can change configurations by tunneling through the energy barrier separating them. It has been an open question as to whether tetrahedrally bonded materials, like amorphous silicon, can support TLS due to the over-constrained nature of their bonding. It is shown in this work that amorphous silicon (a-Si) and hydrogenated amorphous silicon (a-Si:H) have specific heat CP in excess of the Debye specific heat which depends on the details of the growth process. There is a linear term that is due to TLS in addition to an excess T3 contribution. We find that the TLS density depends on number density of atoms in the a-Si film and that the presence of hydrogen in a-Si:H increases CP further. We suggest that regions of low density are sufficiently under-constrained to support tunneling between structural configurations at low temperature as described by the TLS model. The presence of H further lowers the energy barriers for the tunneling process resulting in an increase in TLS density in a-Si:H. The presence of H in a-Si:H network is found to be metastable. Annealing causes H to diffuse away from clustered regions which reduces the density of TLS. A low temperature anomaly is found in the a-Si:H films in their as prepared state that is of unknown origin but appears to take the form of a broadened Schottky anomaly. This feature is removed upon annealing. We find that there is a clear link between density of TLS and the excess T3 heat capacity. This correlation is not currently addressed by models of the glassy state. Additionally, a reversible increase in the heat capacity is found upon light soaking in both a-Si and a-Si:H. This increase occurs over the entire measured temperature range 2-300K and can be removed by annealing at 200°C. The light soaked heat capacity at low temperatures has the form of the low energy excitations that are found in glasses. We suggest that the dangling bond defects responsible for the Staebler-Wronski effect are a consequence of the photo-induced structural states.
Download or read book The Physics of Hydrogenated Amorphous Silicon written by John D. Joannopoulos and published by . This book was released on 1984 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gap States in Hydrogenated Amorphous Silicon written by Kazuo Morigaki and published by . This book was released on 1984 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
