Files in this item



application/pdf1984_askew.pdf (5MB)Restricted to U of Illinois


Title:Microwave studies of amorphous silicon
Author(s):Askew, Thomas Rendall
Doctoral Committee Chair(s):Stapleton, H.J.
Department / Program:Physics
Subject(s):amorphous silicon
electron paramagnetic resonance
electron spin relaxation
Abstract:Electron paramagnetic resonance and electron spin relaxation rates of the intrinsic paramagnetic center (g=2.0055) in amorphous silicon have been studied in the 0.3 -1.2 K temperature range. Various sample preparation techniques were used, including ion implantation, sputtering, arid vacuum evaporation. The temperature dependence of the spin lattice relaxation rates depends somewhat on sample preparation but is always very close to simple T power laws. The n values observed in this study fall into two ranges: 2.09 -2.36 and 3.26 -3.47. Comparison of measurements at 9.3 GHz and 16.5 GHz indicates that the observed rates are independent or very nearly independent of microwave frequency and applied magnetic field. Conventional one and two phonon spin lattice relaxation mechanisms cannot account for the observed temperature dependences. A theory involving spin lattice relaxation by coupling to a distribution of two level systems (TLS) is presented. The theory is adjusted so that it can be applied in the relevant temperature range and its predictions are compared to the experimental results. An attempt is made to identify the TLS and the TLS-spin coupling using electron-nuclear double rescnance (ENDOR), microwave frequency dielectric absorption, and magn
Issue Date:1984
Genre:Dissertation / Thesis
Rights Information:1984 Thomas Rendall Askew
Date Available in IDEALS:2011-06-07
Identifier in Online Catalog:826531

This item appears in the following Collection(s)

Item Statistics