상세정보
학술지
Unraveling Interface Characteristics of Zn(O,S)/Cu(In,Ga)Se2 at Nanoscale: Enhanced Hole Transport by Tuning Band Offsets
- 발행일
- 202004
- 출처
- Applied Surface Science, v.509, pp.1-6
- ISSN
- 0169-4332
- 출판사
- Elsevier
- 협약과제
- 19JB1900, 무독성 버퍼층을 갖는 다색 플렉서블 박막 태양전지 기술 개발, 정용덕
- 초록
- Environment-friendly Cu(In,Ga)Se2 (CIGS) solar cells requires the replacement of Cd-containing buffers with non-toxic materials. Zn(O,S) buffers have been developed and yielded even better efficiency than CdS-buffered CIGS thin-film solar cells [23.35%, Ref. [6]]. In this work, we studied band offsets of Zn(O,S) and CIGS interfaces. The Cd-free buffer layers were deposited with 1.0%, 1.3%, and 1.6% oxygen (O2) gas partial pressure during the deposition. Effects of the oxygen partial pressure on the structure and electronic properties of the devices were investigated by micro-Raman scattering spectroscopy and Kelvin probe force microscopy, respectively. We achieved depth-profiling of spatial work function mapping across the interface between the absorbers and the buffers. The best efficiency sample, grown using 1.3% of oxygen, showed 80 mV spike-like band offsets. We propose that the efficiency can be improved through tailoring of the band offsets at the interface as well as improving the absorber and the buffer materials.
- KSP 제안 키워드
- Buffer material, Cd-free buffer layer, Depth profiling(DP), Environment-friendly, Function mapping, Hole transport, Interface characteristics, Kelvin Probe force microscopy, Micro-Raman scattering spectroscopy, Raman scattering(SERS), Structure and electronic properties