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

Yonkil Jeong; Chae-Woong Kim; Dong-Won Park; Seung Chul Jung; Jongjin Lee; Hee-Sang Shim

doi:10.1186/1556-276X-6-581

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

Nanoscale Res Lett. 2011 Nov 7;6(1):581. doi: 10.1186/1556-276X-6-581.

Authors

Yonkil Jeong¹, Chae-Woong Kim, Dong-Won Park, Seung Chul Jung, Jongjin Lee, Hee-Sang Shim

Affiliation

¹ Research Institute for Solar and Sustainable Energies (RISE), Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712, South Korea. thanks21@gist.ac.kr.

Abstract

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.