Electronic structure of carbon-rich a-Si1-xCxHy alloys: The role of hydrogen and graphitic carbon

Xanthakis, JP; Orphanides, P; Katsoulakos, P

dc.contributor.author	Xanthakis, JP	en
dc.contributor.author	Orphanides, P	en
dc.contributor.author	Katsoulakos, P	en
dc.date.accessioned	2014-03-01T01:12:51Z
dc.date.available	2014-03-01T01:12:51Z
dc.date.issued	1997	en
dc.identifier.issn	0953-8984	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/12263
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	X-RAY-ABSORPTION	en
dc.subject.other	SILICON-CARBIDE	en
dc.subject.other	OPTICAL-ABSORPTION	en
dc.subject.other	ATOMIC-STRUCTURE	en
dc.subject.other	FINE-STRUCTURE	en
dc.subject.other	SHORT-RANGE	en
dc.subject.other	STATES	en
dc.subject.other	FILMS	en
dc.subject.other	SPECTROSCOPY	en
dc.subject.other	SYSTEM	en
dc.title	Electronic structure of carbon-rich a-Si1-xCxHy alloys: The role of hydrogen and graphitic carbon	en
heal.type	journalArticle	en
heal.identifier.primary	10.1088/0953-8984/9/10/009	en
heal.identifier.secondary	http://dx.doi.org/10.1088/0953-8984/9/10/009	en
heal.language	English	en
heal.publicationDate	1997	en
heal.abstract	We calculated the electronic structure of carbon-rich a-Si1-xCxHy, an alloy for which there is conflicting experimental evidence for the degree of disorder and the fraction of graphitic carbon atoms present. Our calculation takes into account valence disorder due to carbon and hydrogen as well as short-range order effects. We deduce that, if the alloy is heavily hydrogenated, then Si-Si bonds exist in considerable amount up to x = 0.75 at least. Furthermore the fraction of graphitic carbon atoms increases slowly up to the value of x at which a maximum in the band gap occurs and then it increases rapidly as some experiments seem to confirm. Our calculated band gap as a function of x is in reasonable agreement with experiment and our peaks in the density of states (DOS) correlate well with the peaks of the photoemission spectra whose orbital character we can deduce. We note that our conclusion on the presence of Si-Si bonds is independent of our method of calculating the DOS and derives from our matching of atoms to the corresponding bonds. Finally estimates of the fracton of graphitic atoms at each x are made.	en
heal.publisher	IOP PUBLISHING LTD	en
heal.journalName	Journal of Physics Condensed Matter	en
dc.identifier.doi	10.1088/0953-8984/9/10/009	en
dc.identifier.isi	ISI:A1997WP37600009	en
dc.identifier.volume	9	en
dc.identifier.issue	10	en
dc.identifier.spage	2199	en
dc.identifier.epage	2209	en