Thin Solid Films, 08/2015, Vol.589, C, pp.369-375
To access, purchase, authenticate, or subscribe to the full-text of this article, please visit this link: http://dx.doi.org/10.1016/j.tsf.2015.05.036 Byline: Y.G. Fedorenko (a,1), M.A. Hughes (a), J.L. Colaux (a), C. Jeynes (a), R.M. Gwilliam (a), K. Homewood (a), B. Gholipour (b), J. Yao (b), D.W. Hewak (b), T.-H. Lee (c), S.R. Elliott (c), R.J. Curry (a) Keywords Amorphous chalcogenide; Doping; Ion implantation Highlights * Electron conductivity is observed in Bi-implanted GeTe films. * Higher conductivity in Bi-implanted films stems from increased density of electrically active defects. * Bi implanted in amorphous chalcogenides may promote formation of a more chemically ordered alloy. Abstract The impact of Bi implantation on the conductivity and the thermopower of GeTe, Ge--Sb--Te, and Ga--La--S films is investigated. The enhanced conductivity appears to be notably sensitive to a dose of an implant. Incorporation of Bi in amorphous chalcogenide films at doses up to 1 x 10.sup.15 cm.sup.- 2 is seen not to change the majority carrier type and activation energy for the conduction process. Higher implantation doses may reverse the majority carrier type in the studied films. Electron conductivity was observed in GeTe films implanted with Bi at a dose of 2 x 10.sup.16 cm.sup.- 2. These studies indicate that native coordination defects present in amorphous chalcogenide semiconductors can be deactivated by means of ion implantation. A substantial density of implantation-induced traps in the studied films and their interfaces with silicon is inferred from analysis of the space-charge-limited current and capacitance-voltage characteristics taken on Au/amorphous chalcogenide/Si structures. Author Affiliation: (a) Advanced Technology Institute, Department of Electronic Engineering, University of Surrey, Guildford, GU2 7XH, United Kingdom (b) Optoelectronics Research Centre, University of Southampton, Southampton SO17 1BJ, United Kingdom (c) Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom Article History: Received 4 July 2014; Revised 15 March 2015; Accepted 20 May 2015 (footnote)1 Present address: Stephenson Institute for Renewable Energy, University of Liverpool, Chadwick Building, Peach St., Liverpool L69 7ZF, United Kingdom.
Semiconductors (Materials) – Analysis ; Semiconductors (Materials) – Electric Properties ; Activation Energy – Analysis ; Activation Energy – Electric Properties ; Silicon – Analysis ; Silicon – Electric Properties;