Use this URL to cite or link to this record in EThOS:
Title: The structure of amorphous semiconductor:metal thin-films
Author: Edwards, Ann M.
ISNI:       0000 0001 3438 5576
Awarding Body: University of Kent
Current Institution: University of Kent
Date of Award: 1989
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
A transition from semiconducting to extend state conduction may be induced in certain amorphous semiconductor:metal alloys by increasing the metal concentration above a critical limit. Descriptions of the processes involved in such a transition have generally been based around investigations on electronic properties. However, without a knowledge of the atomic-scale structure of the alloys, it is difficult to ascribe a mechanism to an observed transition. In order to increase the understanding of such processes in semiconductor:metal systems, thin-film samples of three alloy systems (a-Si:Ni:H, a-Si:Sn:H and a-Ge:Au) have been prepared by rf co-sputtering over pertinent composition ranges, and micro-structural studies have been performed using extended X-ray absorption fine structure spectroscopy and other complementary techniques. For low metal concentrations (<20at.%), both a-Si:Ni:H and a-Ge:Au appear to consist of two separate phases: regions of an amorphous Ni:Si or a partially crystalline Au:Ge alloy being embedded in the remaining, modified amorphous matrix provided by a-Si:H and a-Ge respectively. In contrast, Sn atoms appear to substitute randomly into the a-Si:H network. The implications of these results for the interpretation of electrical conductivity data is discussed.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available
Keywords: QC Physics