Title :
Polycrystalline CuIn1-xGaxSe2 thin film PV solar cells prepared by two-stage selenization process using Se vapor
Author :
Dhere, Neelkanth G. ; Kuttath, Shanker ; Lynn, Kevin W. ; Birkmire, Robert W. ; Shafarman, William N.
Author_Institution :
Florida Solar Energy Center, Cape Canaveral, FL, USA
Abstract :
Novel two-stage Se vapor selenization of magnetron sputtered metallic precursors and Ga incorporation using single Cu-Ga(22 at.%) alloy target have been developed for preparation of well-adherent, large, compact, well-faceted polyhedral grain CuIn1-xGax Se2 thin films having optimum composition Cu:In:Ga:Se of 22.95:25.03:1.40:50.63. Cu-In-Ga precursor homogenization by in situ heat-treatment at ~90°C for 10 minutes prior to first selenization, selenization temperature of 550-560°C, and Se vapor incidence rate of 50 Å sec-1 resulted in improved morphology of completed CuIn1-xGa2Se2 thin films, and solar cells with open circuit voltage Voc 377 mV, short circuit current density Jsc of 34.8 mA, fill factor (FF) of 62.5%, active area efficiency of 8.2% (total area efficiency 5.8% limited by FF 49.1%) and fairly constant spectral response over the spectral range
Keywords :
copper compounds; crystal morphology; heat treatment; indium compounds; semiconductor materials; semiconductor thin films; solar cells; sputtered coatings; ternary semiconductors; 10 min; 34.8 mA; 377 mV; 5.8 percent; 550 to 560 C; 8.2 percent; 90 C; Cu-In-Ga precursor homogenization; CuInGeSe2; Ga incorporation; Se vapor; active area efficiency; constant spectral response; fill factor; in situ heat-treatment; magnetron sputtered metallic precursors; morphology; open circuit voltage; polycrystalline CuIn1-xGaxSe2; polyhedral grain; short circuit current density; thin film solar cells; total area efficiency; two-stage selenization process; Copper; Fabrication; Gallium; Photonic band gap; Photovoltaic cells; Residual stresses; Sputtering; Temperature distribution; Thin film circuits; Transistors;
Conference_Titel :
Photovoltaic Energy Conversion, 1994., Conference Record of the Twenty Fourth. IEEE Photovoltaic Specialists Conference - 1994, 1994 IEEE First World Conference on
Conference_Location :
Waikoloa, HI
Print_ISBN :
0-7803-1460-3
DOI :
10.1109/WCPEC.1994.519840
