Title :
Metastable changes of the electrical transport properties of Cu(In,Ga)Se2
Author :
Meyer, Th. ; Schmidt, M. ; Harney, R. ; Engelhardt, F. ; Seifert, O. ; Parisi, J. ; Schmitt, M. ; Rau, U.
Author_Institution :
Fac. of Phys., Oldenburg Univ., Germany
fDate :
29 Sep-3 Oct 1997
Abstract :
The authors investigate the electrical transport properties of Cu(In,Ga)Se2 polycrystalline thin films and solar cells during and after illumination or forward bias in the dark (the latter only for the cells). For the thin films, they find persistent photoconductivity. In the solar cells, they observed relaxation of the open circuit voltage and a metastable increase of the voltage under constant forward current in the dark. Both phenomena are accompanied by an increase in the sample capacitance. They present a model that explains all the observed metastable phenomena as a consequence of trapping of minority carriers in the bulk of the Cu(In,Ga)Se2 material
Keywords :
copper compounds; gallium compounds; indium compounds; metastable states; minority carriers; photoconductivity; semiconductor device models; semiconductor device testing; semiconductor thin films; solar cells; Cu(In,Ga)Se2 polycrystalline thin film solar cells; Cu(InGa)Se2; constant forward current; electrical transport properties; forward bias; illumination; metastable changes; metastable phenomena model; minority carriers trapping; open circuit voltage; photoconductivity; sample capacitance; Admittance measurement; Capacitance; Current measurement; Electron traps; Lighting; Metastasis; Photoconductivity; Photovoltaic cells; Thin film circuits; Voltage;
Conference_Titel :
Photovoltaic Specialists Conference, 1997., Conference Record of the Twenty-Sixth IEEE
Conference_Location :
Anaheim, CA
Print_ISBN :
0-7803-3767-0
DOI :
10.1109/PVSC.1997.654105
