Ga2Se3 층을 Cu-In-Ga 전구체 위에 적용하여 제조된 Cu(In,Ga)Se2 박막의 Ga 분포 변화 연구

정광선; 신영민; 조양휘; 윤재호; 안병태; Gwang Sun Jung; Young Min Shin; Yang Hwi Cho; Jae Ho Yun; Byung Tae Ahn

Korean Journal of Materials Research, Vol.20, No.8, 434-438, August, 2010

DOI10.3740/MRSK.2010.20.8.434 Export Citation

Ga2Se3 층을 Cu-In-Ga 전구체 위에 적용하여 제조된 Cu(In,Ga)Se2 박막의 Ga 분포 변화 연구

Ga Distribution in Cu(In,Ga)Se2 Thin Film Prepared by Selenization of Co-Sputtered Cu-In-Ga Precursor with Ga2Se3 Layer

정광선, 신영민, 조양휘, 윤재호¹, 안병태^†

한국과학기술원 신소재공학과
¹한국에너지기술연구원

Gwang Sun Jung, Young Min Shin, Yang Hwi Cho, Jae Ho Yun¹, and Byung Tae Ahn^†

Department of Materials Science and Engineering, KAIST, Daejeon 305-701, Korea
¹Korea Institute of Energy and Research, Daejeon 305-343, Korea

E-mail:

The selenization process has been a promising method for low-cost and large-scale production of high quality CIGS film. However, there is the problem that most Ga in the CIGS film segregates near the Mo back contact. So the solar cell behaves like a CuInSe2 and lacks the increased open-circuit voltage. In this study we investigated the Ga distribution in CIGS films by using the Ga2Se3 layer. The Ga2Se3 layer was applied on the Cu-In-Ga metal layer to increase Ga content at the surface of CIGS films and to restrict Ga diffusion to the CIGS/Mo interface with Ga and Se bonding. The layer made by thermal evaporation was showed to an amorphous Ga2Se3 layer in the result of AES depth profile, XPS and XRD measurement. As thethickness of Ga2Se3 layer increased, a small-grained CIGS film was developed and phase seperation was showed using SEM and XRD respectively. Ga distributions in CIGS films were investigated by means of AES depth profile. As a result, the [Ga]/[In+Ga] ratio was 0.2 at the surface and 0.5 near the CIGS/Mo interface when the Ga2Se3 thickness was 220 nm, suggesting that the Ga2Se3 layer on the top of metal layer is one of the possible methods for Ga redistribution and open circuit voltage increase.

Keywords:Ga distribution;Cu(In,Ga)Se2;thin-films;selenization

[References]

Park TJ, Shin DH, Ahn BT, Yun JH, Korean J. Mater. Res., 19(8), 452 (2009)
Romeo A, Terheggen M, Abou-Ras D, Batzner DL, Haug FJ, Kalin M, Rudmann D, Tiwari AN, Prog. Photovoltaics, 12, 93 (2004)
Alberts V, Semicond. Sci. Tech., 19, 65 (2004)
Hanket GM, Shafarman WN, McCandless BE, Birkmire RW, J. Appl. Phys., 102, 074922 (2007)
Marudachalam M, Birkmire RW, Hichri H, Schultz JM, Swartzlander A, Al-Jassim MM, J. Appl. Phys., 82, 2896 (1997)
Kim MS, Chalapathy RBV, Yoon KH, Ahn BT, J. Electrochem. Soc., 157(1), B154 (2010)
Kim MS, Lee JC, Yun JH, Ahn BT, in proceedings of International Conference on Microelectronics and Plasma Technology (Jeju, Korea, Aug 2008) p. 224. (2008)

[1] Park TJ, Shin DH, Ahn BT, Yun JH, Korean J. Mater. Res., 19(8), 452 (2009)

[2] Romeo A, Terheggen M, Abou-Ras D, Batzner DL, Haug FJ, Kalin M, Rudmann D, Tiwari AN, Prog. Photovoltaics, 12, 93 (2004)

[3] Alberts V, Semicond. Sci. Tech., 19, 65 (2004)

[4] Hanket GM, Shafarman WN, McCandless BE, Birkmire RW, J. Appl. Phys., 102, 074922 (2007)

[5] Marudachalam M, Birkmire RW, Hichri H, Schultz JM, Swartzlander A, Al-Jassim MM, J. Appl. Phys., 82, 2896 (1997)

[6] Kim MS, Chalapathy RBV, Yoon KH, Ahn BT, J. Electrochem. Soc., 157(1), B154 (2010)

[7] Kim MS, Lee JC, Yun JH, Ahn BT, in proceedings of International Conference on Microelectronics and Plasma Technology (Jeju, Korea, Aug 2008) p. 224. (2008)