Title :
Buried pn homojunction in Cu(InGa)Se2 solar cells formed by intentional Zn doping
Author :
Yamada, Akira ; Sugiyama, Takeshi ; Chaisitsak, Sutichai ; Konagai, Makoto ; Kudriavtsev, Yuriy ; Godines, Antonio ; Villegas, Antonio ; Asomoza, Rene
Author_Institution :
Dept. of Electr. & Electron. Eng., Tokyo Inst. of Technol., Japan
Abstract :
In this study, we tried intentional doping and fabrication of a pn homojunction at the surface of the Cu(InGa)Se2 (CIGS) solar cell by Zn evaporation. For Zn doping of the CIGS layer, Zn was evaporated after CIGS formation and we successfully demonstrated a potential improvement in cell performance by this technique. Furthermore, Zn diffusion into the CIGS film was investigated by secondary ion mass spectroscopy (SIMS). A conductivity-type conversion from p-type to n-type was studied by the measurement of the cross-sectional electron beam-induced current (junction EBIC: JEBIC) and the spectral response of solar cells. A conversion efficiency of 11.5 % has been achieved using the Zn-doped CIGS layer without a buffer layer and by the formation of a pn homojunction in the CIGS absorber
Keywords :
EBIC; copper compounds; diffusion; evaporation; gallium compounds; indium compounds; p-n junctions; secondary ion mass spectroscopy; semiconductor doping; solar cells; ternary semiconductors; zinc; 11.5 percent; Cu(InGa)Se2; Cu(InGa)Se2 solar cells; JEBIC; Zn; Zn diffusion; Zn evaporation; Zn-doped CIGS layer; buried pn homojunction; cell performance; conversion efficiency; cross-sectional electron beam-induced current; intentional Zn doping; junction EBIC; secondary ion mass spectroscopy; spectral response; Buffer layers; Conductivity; Doping; Electrons; Fabrication; Mass spectroscopy; Molecular beam epitaxial growth; Photovoltaic cells; Sputtering; Zinc oxide;
Conference_Titel :
Photovoltaic Specialists Conference, 2000. Conference Record of the Twenty-Eighth IEEE
Conference_Location :
Anchorage, AK
Print_ISBN :
0-7803-5772-8
DOI :
10.1109/PVSC.2000.915871
