Effect of poly-Si Thickness and Firing Temperature on Metal Induced Recombination and Contact Resistivity of TOPCon Solar Cells

Sang Hee Lee; Hee Jun Yang; Uk Chul Lee; Joon Sung Lee; Hee-eun Song; Min Gu Kang; Jae Ho Yoon; Sungeun Park

doi:10.21218/CPR.2021.9.4.128

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Effect of poly-Si Thickness and Firing Temperature on Metal Induced Recombination and Contact Resistivity of TOPCon Solar Cells Poly-Si 두께와 인쇄전극 소성 온도가 TOPCon 태양전지의 금속 재결합과 접촉비저항에 미치는 영향

31 December 2021. pp. 128-132

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Abstract

Advances in screen printing technology have been led to development of high efficiency silicon solar cells. As a post PERx structure, an n-type wafer-based rear side TOPCon structure has been actively researched for further open-circuit voltage (Voc) improvement. In the case of the metal contact of the TOPCon structure, the poly-Si thickness is very important because the passivation of the substrate will be degraded when the metal paste penetrates until substrate. However, the thin poly-Si layer has advantages in terms of current density due to reduction of parasitic absorption. Therefore, poly-Si thickness and firing temperature must be considered to optimize the metal contact of the TOPCon structure. In this paper, we varied poly-Si thickness and firing peak temperature to evaluate metal induced recombination (Jom) and contact resistivity. Jom was evaluated by using PL imaging technique which does not require both side metal contact. As a results, we realized that the SiN_x deposition conditions can affect the metal contact of the TOPCon structure.

Keywords

TOPCon

Screen printed metal contact

Metal induced recombination

Photoluminescence imaging

Contact resistivity

References

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Information

Publisher :Korea Photovoltaic Society
Publisher(Ko) :한국태양광발전학회
Journal Title :Current Photovoltaic Research
Volume : 9
No :4
Pages :128-132
Received Date : 2021-09-16
Revised Date : 2021-10-19
Accepted Date : 2021-10-29
DOI :https://doi.org/10.21218/CPR.2021.9.4.128

Current Photovoltaic Research ISSN:2288-3274(Print) 2508-125X(Online)

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