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2026 Vol.14, Issue 3
Effect of a Polyethylene Terephthalate Film Buffer Layer on Electrode Interfacial Contact and Output Characteristics in Low-Temperature Integrated Solar Cell Module Packaging

저온 일체화 태양전지 모듈 패키징에서의 PET film 완충층 구조가 전극 계면 접촉 및 출력 특성에 미치는 영향

Sung Jun Cho1
,
Min Gyu Kwak1
,
Yong Joon Kwon1
,
Seong Deok Seo1
,
Sun Woo Yun1
,
Woo Chang Song2
,
Donggun Lim1*
조 성준1
,
곽 민규1
,
권 용준1
,
서 성덕1
,
윤 선우1
,
송 우창2
,
임 동건1*
1Department of Electronic engineering, Korea National University of Transportation, Chungju, 27469, Korea
2Department of Electrical engineering, Kangwon National University, Samcheok, 25913, Korea
1전자공학과, 국립한국교통대학교, 충주, 27469
2전기공학과, 강원대학교, 삼척, 25913
*Corresponding Author
30 September 2026. pp. 97-102
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Abstract

Low-temperature integrated packaging can reduce thermal stress and cell damage caused by conventional high-temperature interconnection. This study compared three wire attachment structures using 60Sn40Pb solder-coated wires and then evaluated 60Sn40Pb and low-melting-point 40.5Sn58Bi1.5Ag solder-coated wires under the same polyethylene terephthalate film buffer-layer structure. Direct attachment to ethylene-vinyl acetate sheets caused wire deformation and lifting from finger electrodes because of thermal shrinkage, increasing interfacial contact resistance. Inserting a polyethylene terephthalate film between the sheet and wires suppressed deformation and enhanced compressive force during lamination. Consequently, module efficiency increased by approximately 10% compared with direct attachment. The 40.5Sn58Bi1.5Ag solder increased open-circuit voltage, short-circuit current, and maximum output power compared with 60Sn40Pb solder. Temperature-dependent analysis showed that sufficient solder melting and increased fill factor produced the highest module efficiency of 19.7% at 170°C. These results demonstrate that the film buffer layer improves interfacial contact stability and module output in low-temperature integrated packaging.

Keywords
PV module
Low-temperature integrated packaging
Busbarless solar cell
Contact resistivity
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 14
  • No :3
  • Pages :97-102
  • Received Date : 2026-08-19
  • Revised Date : 2026-09-09
  • Accepted Date : 2026-09-09
  • DOI :https://doi.org/10.21218/CPR.2026.14.3.097
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