A THEORETICAL-STUDY OF STOICHIOMETRIC AND AS-RICH AMORPHOUS GAAS

XANTHAKIS, JP; KATSOULAKOS, P; GEORGIAKOS, D

dc.contributor.author	XANTHAKIS, JP	en
dc.contributor.author	KATSOULAKOS, P	en
dc.contributor.author	GEORGIAKOS, D	en
dc.date.accessioned	2014-03-01T01:42:02Z
dc.date.available	2014-03-01T01:42:02Z
dc.date.issued	1993	en
dc.identifier.issn	0953-8984	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/23685
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	ELECTRONIC-STRUCTURE	en
dc.subject.other	OPTICAL-PROPERTIES	en
dc.subject.other	III-V	en
dc.subject.other	DISORDER	en
dc.subject.other	ALLOYS	en
dc.subject.other	GAP	en
dc.subject.other	SEMICONDUCTORS	en
dc.subject.other	DEFECTS	en
dc.subject.other	SYSTEM	en
dc.title	A THEORETICAL-STUDY OF STOICHIOMETRIC AND AS-RICH AMORPHOUS GAAS	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	1993	en
heal.abstract	We have investigated the electronic and atomistic structure of stoichiometric and As-rich GaAs by treating this material as a ternary alloy of fourfold-coordinated As4+, Ga3+ and threefold-coordinated As3+. Using the configurational averaging technique of Verges we have calculated the density of states (DOS) of this material, not only in terms of the stoichiometric index x and proportion of As3+ atoms alpha, but also in terms of the short-range order (SRO) parameters. By correlating with experiment we obtain valuable information about the SRO. In particular, we have shown that compensation occurs at a value of alpha that is a function of x only. Using this value of alpha and assuming that less than 1% of As4+-As4+ bonds occur (all other As-As bonds being allowed) we were able to (i) reproduce the EXAFS data and the variation of the optical gap with x and (ii) account for the observed shoulder in the lowest peak of the valence band and the subsidiary shell of As neighbours of Ga. Finally, at other values of the SRO parameters, we find features in the Dos that could explain some experiments on other amorphous III-V semiconductors.	en
heal.publisher	IOP PUBLISHING LTD	en
heal.journalName	JOURNAL OF PHYSICS-CONDENSED MATTER	en
dc.identifier.isi	ISI:A1993MH24900007	en
dc.identifier.volume	5	en
dc.identifier.issue	46	en
dc.identifier.spage	8677	en
dc.identifier.epage	8688	en