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2026 Vol.14, Issue 1 Preview Page
Analysis of the surface passivation characteristics of crystalline silicon solar cells following subsequent heat treatment of Al2O3 thin films

Al2O3 박막의 후속 열처리에 따른 결정질 실리콘 태양전지 표면 패시베이션 특성 분석

Munse Kim12
,
Yunae Cho1
,
Yong-Jin Kim1
,
Unsoo Kim1
,
Hyungwoo Kim1
,
Kyung Taek Jeong1
,
Hae-Seok Lee2
,
Chelwook Kwon12
,
Kyuhyeon Im12
,
Minseo Kim12
,
Hee-eun Song1*
,
Sang Hee Lee1*
김 문세12
,
조 윤애1
,
김 용진1
,
김 언수1
,
김 형우1
,
정 경택1
,
이 해석2
,
권 철욱12
,
임 규현12
,
김 민서12
,
송 희은1*
,
이 상희1*
1Photovoltaics Research Department, Korea Institute of Energy Research, 34129, Daejeon, Republic of Korea
2Graduate School of Energy and Environment (KU-KIST Green School), Korea University, 02841, Seoul, Republic of Korea
1태양광연구단, 한국에너지기술연구원, 대전, 34129
2에너지환경대학원 (KU-KIST Green School), 고려대학교, 서울, 02841
*Corresponding Author
31 March 2026. pp. 32-37
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Abstract

Effective surface passivation is essential for high-efficiency crystalline silicon (c-Si) solar cells. Aluminum oxide (Al2O3) films deposited via atomic layer deposition (ALD) are a leading passivation material due to their high negative fixed charge density (Qf) and low interface trap density (Dit). However, the optimal passivation performance is highly dependent on the post-deposition annealing (PDA) temperature, a relationship that is often reported inconsistently in the literature. This study systematically investigates the integrated passivation mechanism of an ~10 nm amorphous AlOx film on c-Si. By precisely controlling the PDA temperature, we employ combined electrical, chemical, and optoelectronic analyses to link process condition to passivation performance. Our findings reveal that both the magnitude of negative Qf and the overall passivation quality are maximized at a PDA temperature of approximately 450°C. Fourier-transform infrared (FT-IR) spectroscopy confirms that this optimal performance correlates with densification and rearrangement of the Al-O network, which stabilizes negative charge centers near the interface. At higher temperatures (≥ 500°C), a clear decline in passivation is observed, which we attribute to the growth of an interfacial SiO2 layer and hydrogen loss. This study establishes a direct link between PDA temperature, structural changes, and passivation performance, providing quantitative, physically grounded guidelines for optimizing Al2O3-based passivation in high-efficiency c-Si solar cells.

Keywords
Aluminum oxide (Al2O3)
Post-Deposition Annealing (PDA)
Surface passivation
solar cells
Atomic Layer Deposition (ALD)
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 14
  • No :1
  • Pages :32-37
  • Received Date : 2025-09-13
  • Revised Date : 2025-11-11
  • Accepted Date : 2025-11-12
  • DOI :https://doi.org/10.21218/CPR.2026.14.1.032
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