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2021 Vol.9, Issue 3 Preview Page
Characterization of an In2Se3 Passivation Layer for CIGS Solar Cells with Cd-free Zn-containing Atomic-layer-deposited Buffers
Suncheul Kim12
,
Ho Jin Lee1
,
Byung Tae Ahn1*
,
Dong Hyeop Shin3
,
Kihwan Kim3
,
Jae Ho Yun3**
1Department of Material Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea
2Metal Process Technology Team, Memory Division, Samsung Electronics, Gyunggi 18448, Korea
3Photovoltaic Team, Korea Institute of Energy Research, Daejeon 34129, Korea
*Corresponding Author
**Corresponding Author
30 September 2021. pp. 96-105
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Abstract

Even though above 22% efficiencies have been reported in Cd-free Cu(In,Ga)Se2 (CIGS) solar cell with Zn-containing buffers, the efficiencies with Zn-containing buffers, in general, are well below 20%. One of the reasons is Zn diffusion from the Zn-containing buffer layer to CIGS film during buffer growth. To avoid the degradation, it is necessary to prevent the diffusion of Zn atoms from Zn-containing buffer to CIGS film. For the purpose, we characterized an In2Se3 film as a possible diffusion barrier layer because In2Se3 has no Zn component. It was found that an In2Se3 layer grown at 300°C was very effective in preventing Zn diffusion from a Zn-containing buffer. Also, the In2Se3 had a large potential barrier in the valence band at the In2Se3/CIGS interface. Therefore, In2Se3 passivation has the potential to achieve a super-high efficiency in CIGS solar cells that employ Cd-free ALD processed buffers containing Zn.

Keywords
Cu(In,Ga)Se2 solar cells
In2Se3 passivation layer
Zn diffusion
hole blocking
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 9
  • No :3
  • Pages :96-105
  • Received Date : 2021-07-26
  • Revised Date : 2021-09-06
  • Accepted Date : 2021-09-09
  • DOI :https://doi.org/10.21218/CPR.2021.9.3.096
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