Accession Number : ADA192277

Title :   Defects and Disorder in Amorphous and Damaged Silicon.

Descriptive Note : Final rept. May 84-Jun 87,

Corporate Author : OXFORD UNIV (ENGLAND) DEPT OF THEORETICAL PHYSICS

Personal Author(s) : Elliott, Roger J

PDF Url : ADA192277

Report Date : Dec 1987

Pagination or Media Count : 13

Abstract : This study of defects and disorder in Si has focussed on models of excitation near defects in the crystal, in structurally disordered amorphous material, and at interfaces between crystal and amorphous material. The first section deals with the vibrations of Si slabs with (111) faces subject to varying boundary conditions. In particular slabs with free boundaries, with dangling bonds saturated by hydrogen, and slabs embedded in amorphous material were considered. The shift and broadening of the Raman peak was calculated and it was shown how this could be used to obtain estimates of crystallyte size in disordered material. The main work related to a model of electron states at an interface between crystalline Si and amorphous SiO2. The latter material was modelled using a Bethe lattice. The final component of the work was a study of various aspects of electronic energy levels in quantum wells. The detailed form of the hole band structure including the anomalous dispersion of the sub-bands was examined in detail, as was the non-parabolicity of the conduction sub-bands. The effect of these changes on the exciton binding energy was examined in some detail for several systems.

Descriptors :   *DEFECTS(MATERIALS), *SILICON, *SEMICONDUCTORS, AMORPHOUS MATERIALS, BONDED JOINTS, ELECTRON ENERGY, ELECTRONIC STATES, ENERGY LEVELS, EXCITONS, ORDER DISORDER TRANSFORMATIONS, QUANTUM ELECTRONICS, RAMAN SPECTRA, VIBRATION, SILICON DIOXIDE, CRYSTAL LATTICES, GALLIUM ARSENIDES

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE