Degree Type

Dissertation

Date of Award

1982

Degree Name

Doctor of Philosophy

Department

Physics and Astronomy

Abstract

Proton magnetic resonance and electron paramagnetic resonance measurement results are presented for several reactively sputtered amorphous silicon-hydrogen alloys and for a few amorphous silicon-hydrogen-deuterium alloys. Proton NMR absorption measurements made on a series of samples with controlled and varied amounts of hydrogen have been interpreted as evidence for significant inhomogeneity in the local hydrogen density: there is a phase of the material, in which the hydrogen bonded to Si is randomly distributed with average local density 3.39 x 10('21) cm('-3); there is a hydrogen cluster defect with average local hydrogen density 4.34 x 10('22) cm('-3); in the lower hydrogen samples there is a third phase of the material which has no H;Proton NMR spin-lattice relaxation measurements as a function of both temperature and H concentration have been interpreted, consistent with the above conclusions. The mechanism of spin-lattice relaxation in both cases involves spin diffusion to relaxation centers. In the low H concentration samples the relaxation centers are dangling bond electrons, while the centers in the high H samples appear to be three-center Si-H-Si bonds;EPR measurements on the dangling bond electrons are consistent with all of the above conclusions. Furthermore, a new very broad ((TURN).1 Tesla) resonance has been detected in all of the samples. It is tentatively interpreted in support of the existence of three-center bonds;The implications these results may have for the electronic device properties of this material are discussed.

DOI

https://doi.org/10.31274/rtd-180813-6000

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Mark E. Lowry

Language

en

Proquest ID

AAI8224230

File Format

application/pdf

File Size

227 pages

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