Electrical conduction effects at low temperatures in undoped ZnO thin films grown by Pulsed Laser Deposition on Si substrates

Brilis,; Tsamakis, D; Ali, H; Krishnamoorthy, S; Iliadis, AA

dc.contributor.author	Brilis,	en
dc.contributor.author	Tsamakis, D	en
dc.contributor.author	Ali, H	en
dc.contributor.author	Krishnamoorthy, S	en
dc.contributor.author	Iliadis, AA	en
dc.date.accessioned	2014-03-01T01:28:14Z
dc.date.available	2014-03-01T01:28:14Z
dc.date.issued	2008	en
dc.identifier.issn	0040-6090	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18777
dc.subject	Acceptor band	en
dc.subject	Hopping conductivity	en
dc.subject	Laser ablation	en
dc.subject	Si	en
dc.subject	Zinc-oxide	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.classification	Materials Science, Coatings & Films	en
dc.subject.classification	Physics, Applied	en
dc.subject.classification	Physics, Condensed Matter	en
dc.subject.other	Electric conductivity	en
dc.subject.other	Film growth	en
dc.subject.other	Laser ablation	en
dc.subject.other	Pulsed laser deposition	en
dc.subject.other	Silicon	en
dc.subject.other	Zinc oxide	en
dc.subject.other	Acceptor bands	en
dc.subject.other	Hopping conductivity	en
dc.subject.other	Thin films	en
dc.title	Electrical conduction effects at low temperatures in undoped ZnO thin films grown by Pulsed Laser Deposition on Si substrates	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.tsf.2007.12.137	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.tsf.2007.12.137	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The electrical properties of undoped ZnO films grown by Pulsed Laser Deposition on Si substrates at growth temperatures between 150 and 250 degrees C and low O-2 partial pressures, were studied by resistivity and Hall coefficient measurements in the temperature range of 80 to 350 K. We report acceptor band and hopping conduction effects in these ZnO films, for the first time. P-type conduction is found to be dominant in these films for temperatures higher than approximately 235 K, while at temperatures lower than 235 K the films exhibit a conversion from p- to n-type conductivity. The electrical conductivity studies revealed a conduction mechanism by hopping in the acceptor band in the temperature range between 80 and 270 K. For temperatures higher than 270 K a thermally activated behavior, between the native acceptor band (Zn vacancies) and the valence band is dominant. The acceptor activation energy values extracted from the hip versus T-1 curves were found to be of 0.1 eV The electrical mobility values fall-off rapidly from 90 to 8 cm(2)/V s for temperatures below 270 K, providing evidence that a mobility edge exists between transport in the valence band and transport in the acceptor band. (c) 2008 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE SA	en
heal.journalName	Thin Solid Films	en
dc.identifier.doi	10.1016/j.tsf.2007.12.137	en
dc.identifier.isi	ISI:000255125900082	en
dc.identifier.volume	516	en
dc.identifier.issue	12	en
dc.identifier.spage	4226	en
dc.identifier.epage	4231	en