상세정보
학술지
Double-Layered Ag-Al Back Reflector on Stainless Steel Substrate for a-Si:H Thin Film Solar Cells
- 발행일
- 201602
- 출처
- Solar Energy Materials & Solar Cells, v.145 no.3, pp.368-374
- ISSN
- 0927-0248
- 출판사
- Elsevier
- 협약과제
- 13VB6200, 25%급 광대역 흡수 실리콘 양자점 태양전지 개발, 윤선진
- 초록
- An effective light trapping method for substrate-type hydrogenated amorphous silicon (a-Si:H) thin film solar cells is the use of a back reflector (BR) of high roughness, e.g., 'hot silver', which is deposited at temperatures higher than 450 °C. In this work, textured silver-aluminum (Ag-Al) BR films were fabricated by depositing Ag on Al film at Ag-deposition temperatures (TAg) ranging from 25 to 350 °C. The surface morphology and roughness of Ag-Al films were strongly affected by TAg. The Al and Ag films were formed entirely of Ag2Al alloy at TAg of 330 °C or higher, while the Ag-Al films maintained a double-layered structure at 290 °C or below. Although the films did not undergo alloying at TAg of 290 °C, the Ag-Al films have a well-developed surface structure with high diffuse-reflectance, compared to Ag films deposited at the same temperature. The conversion efficiency of an a-Si:H thin film solar cell on a flexible stainless steel substrate increased from 7.63% to 8.44% as TAg was increased from 25 to 290 °C, as a result of more effective light scattering by Ag-Al BRs, producing increased short-circuit current. However, at higher TAg, Ag2Al alloy films with sharp crystallite edges were formed, and were not appropriate as BRs. The present work clearly shows that double-layered Ag-Al films fabricated at temperatures as low as 290 °C could be useful back reflectors for substrate-type thin film solar cells.
- KSP 제안 키워드
- Ag film, Ag-Al, Al alloy films, Al film, As 2, Back reflector, Conversion efficiency(C.E.), Double layered, Layered structure, Short-Circuit Current, Stainless steel(SUS316)