Title :
ZnGeAs2 thin films properties: A potentially useful semiconductor for photovoltaic applications
Author :
Peshek, T.J. ; Tang, Z. ; Zhang, L. ; Singh, R.K. ; To, B. ; Gessert, T.A. ; Coutts, T.J. ; Newman, N. ; Van Schilfgaarde, M.
Author_Institution :
Sch. of Mater., Arizona State Univ., Tempe, AZ, USA
Abstract :
We have studied the chalcopyrite compound ZnGeAs2 to access its potential as a novel photovoltaic material. Thin films of ZnGeAs2 have been produced by pulsed laser deposition.The films are deposited at 315°C and are amorphous. They crystallize above 450°C and improve in crystallinity up to and including 600°C. At that temperature the Hall mobility is 55 ± 2 cm2/Vs, which is within uncertainty to the highest mobility ever reported for this material. We find a rather high carrier concentration, of order 1018 - 1019 for the annealed films, presumably due to the presence of Zn vacancies. The material is an effective light absorber, with an absorption coefficient of order 104 1/cm at 1.2 eV. These properties suggest ZnGeAs2 may be used to produce cost effective and efficient solar cells.
Keywords :
Hall mobility; absorption coefficients; annealing; crystallisation; germanium compounds; pulsed laser deposition; semiconductor thin films; solar cells; ternary semiconductors; vacancies (crystal); zinc compounds; Hall mobility; ZnGeAs2; absorption coefficient; amorphous films; annealed films; chalcopyrite compound; crystallinity; crystallization; light absorber; photovoltaic applications; pulsed laser deposition; semiconductor thin films; solar cells; temperature 315 degC; vacancies; Amorphous materials; Crystalline materials; Crystallization; Optical materials; Optical pulses; Photovoltaic systems; Pulsed laser deposition; Solar power generation; Sputtering; Temperature;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2009 34th IEEE
Conference_Location :
Philadelphia, PA
Print_ISBN :
978-1-4244-2949-3
Electronic_ISBN :
0160-8371
DOI :
10.1109/PVSC.2009.5411281
