Title :
Electrical and compositional characterization of gallium grading in Cu(In,Ga)Se2 solar cells
Author :
West, Bradley ; Guthrey, Harvey ; Lei Chen ; Jeffries, A. ; Bernardini, S. ; Lai, Binghua ; Maser, Jorg ; Shafarman, William ; Al-Jasim, Mowafak ; Bertoni, M.
Author_Institution :
Ira A. Fulton Schools of Eng., Arizona State Univ., Tempe, AZ, USA
Abstract :
Cu(In,Ga)Se2 (CIGS) solar cells were characterized in cross section using electron beam induced current (EBIC) and synchrotron based x-ray fluorescence (XRF) measurements. Samples with varying gallium ratios and growth methods were compared. A correlation was observed between the compositional gallium grading profile from XRF and carrier activity seen in EBIC through the thickness of the CIGS layer. Samples with steep back grading showed carrier activity isolated near the CIGS/CdS interface, whereas a more uniform grading resulted in carrier activity seen throughout the absorber layer. `Notch´ grading showed only slight variation in EBIC profile compared to a back graded sample with similar gallium ratios.
Keywords :
EBIC; III-VI semiconductors; X-ray fluorescence analysis; cadmium compounds; copper compounds; gallium compounds; indium compounds; solar cells; synchrotrons; ternary semiconductors; CIGS solar cells; Cu(InGa)Se2-CdS; EBIC; XRF measurements; compositional characterization; electrical characterization; electron beam induced current; gallium grading; notch grading; synchrotron based X-ray fluorescence; Correlation; Energy resolution; Gallium; Indexes; Market research; RNA; Weight measurement; CIGS; EBIC; band gap grading; chalcopyrite; synchrotron; thin film; x-ray fluorescence;
Conference_Titel :
Photovoltaic Specialist Conference (PVSC), 2014 IEEE 40th
Conference_Location :
Denver, CO
DOI :
10.1109/PVSC.2014.6925254
