Field modulation in Na-incorporated Cu(In,Ga)Se2 (CIGS) polycrystalline films influenced by alloy-hardening and pair-annihilation probabilities

Nanoscale Research Letters - Tập 6 - Trang 1-6 - 2011
Yonkil Jeong1, Chae-Woong Kim2, Dong-Won Park1, Seung Chul Jung2, Jongjin Lee1, Hee-Sang Shim1
1Research Institute for Solar and Sustainable Energies (RISE), Gwangju Institute of Science and Technology (GIST), Buk-gu, Gwangju, South Korea
2Korea Institute of Industrial Technology, Buk-gu, Gwangju, South Korea

Tóm tắt

The influence of Na on Cu(In,Ga)Se2 (CIGS) solar cells was investigated. A gradient profile of the Na in the CIGS absorber layer can induce an electric field modulation and significantly strengthen the back surface field effect. This field modulation originates from a grain growth model introduced by a combination of alloy-hardening and pair-annihilation probabilities, wherein the Cu supply and Na diffusion together screen the driving force of the grain boundary motion (GBM) by alloy hardening, which indicates a specific GBM pinning by Cu and Na. The pair annihilation between the ubiquitously evolving GBMs has a coincident probability with the alloy-hardening event. PACS: 88. 40. H-, 81. 10. Aj, 81. 40. Cd,

Tài liệu tham khảo

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