Carbon- and oxygen-free Cu(InGa)(SSe)₂ solar cell with a 4.63% conversion efficiency by electrostatic spray deposition.
We have demonstrated the first example of carbon- and oxygen-free Cu(In,Ga)(SSe)2 (CIGSSe) absorber layers prepared by electrospraying a CuInGa (CIG) precursor followed by annealing, sulfurization, and selenization at elevated temperature. X-ray diffraction and scanning electron microscopy showed that the amorphous as-deposited (CIG) precursor film was converted into polycrystalline CIGSSe with a flat-grained morphology after post-treatment. The optimal post-treatment temperature was 300 °C for annealing and 500 °C for both sulfurization and selenization, with a ramp rate of 5 °C/min. The carbon impurities in the precursor film were removed by air annealing, and oxide that was formed during annealing was removed by sulfurization. The fabricated CIGSSe solar cell showed a conversion efficiency of 4.63% for a 0.44 cm(2) area, with Voc = 0.4 V, Jsc = 21 mA/cm(2), and FF = 0.53.
School of Mechanical Engineering, Korea University , Anam-Dong, Seongbuk-Gu, Seoul 136-713, Korea.
Hyun
H
Yoon
Seung Heon
SH
Na
Jae Young
JY
Choi
Min Woo
MW
Kim
Hayong
H
Kim
Hee Sang
HS
An
Byoung Koun
BK
Min
SeJin
S
Ahn
Jae Ho
JH
Yun
Jihye
J
Gwak
KyungHoon
K
Yoon
Sanjay S
SS
Kolekar
Maikel F A M
MF
van Hest
Salem S
SS
Al-Deyab
Mark T
MT
Swihart
Sam S
SS
Yoon