Premium
Flexible Cu(In,Ga)Se 2 solar cell on stainless steel substrate deposited by multi‐layer precursor method: its photovoltaic performance and deep‐level defects
Author(s) -
Chantana Jakapan,
Hironiwa Daisuke,
Watanabe Taichi,
Teraji Seiki,
Minemoto Takashi
Publication year - 2016
Publication title -
progress in photovoltaics: research and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.286
H-Index - 131
eISSN - 1099-159X
pISSN - 1062-7995
DOI - 10.1002/pip.2748
Subject(s) - copper indium gallium selenide solar cells , materials science , solar cell , substrate (aquarium) , analytical chemistry (journal) , deep level transient spectroscopy , layer (electronics) , energy conversion efficiency , atom (system on chip) , optoelectronics , silicon , nanotechnology , chemistry , oceanography , chromatography , geology , computer science , embedded system
Cu(In,Ga)Se 2 (CIGS) films on soda‐lime glass and stainless steel (SUS) substrates with several [Ga]/([Ga] + [In]), GGI, and Fe concentrations are fabricated by so‐called “multi‐layer precursor method”. From optical deep‐level transient spectroscopy, deep‐level defect located at 0.8 eV from valence band maximum ( E V ) is observed. This defect becomes recombination center when GGI is over 0.4, thereby decreasing cell performances. Fe‐related deep‐level defect is moreover detected in CIGS film on SUS substrate situated at 0.45 eV from E V . Its density is consistent with Fe concentration in CIGS films. According to SCAPS simulation and experimental results, Fe concentration of above threshold (1.0 × 10 16 atom/cm 3 ) decreases carrier lifetime and carrier density and has more harmful influence on cell performances with GGI of above 0.4. On the other hand, Fe concentration of below threshold (1.0 × 10 16 atom/cm 3 ) has no detrimental impact on cell performances. Namely, conversion efficiency ( η ) is slightly changed by below 2%. CIGS solar cell on SUS substrate with η of 17.5% is fabricated by decreasing Fe concentration to approximately 5.2 × 10 16 atom/cm 3 although higher than the threshold value. Copyright © 2016 John Wiley & Sons, Ltd.