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2026 Vol.14, Issue 1 Preview Page
Metal Halide Templating Layers for Inverted Wide-Bandgap Perovskite Solar Cells via Dry Vacuum Sublimation

건식 진공 승화법을 이용한 역구조 와이드 밴드갭 페로브스카이트 태양전지용 금속 할로겐 탬플릿 층

Jong Hun Yeo1
,
Seung-Woo Kim1
,
Su Ji Moon1
,
Nam Joong Jeon1*
,
Beom Soo Kim1*
여 종훈1
,
김 승우1
,
문 수지1
,
전 남중1*
,
김 범수1*
1Division of Photoenergy Research Center, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 34114, Korea
1광에너지연구센터, 한국화학연구원, 대전, 대한민국, 34114
*Corresponding Author
31 March 2026. pp. 25-31
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Abstract

The impact of bottom-layer selection on the structual, optical, and photovoltaic properties of vacuum-deposited perovskite films was systematically investigated. Atomic force microscopy (AFM) revealed that films grown on CsI exhibited the lowest root-mean-square(RMS) roughness (16.2 nm) and densely packed, large grains, indicating reduced defect density and suppressed non-radiative recombination, X-ray diffraction (XRD) and UV-Vis spectroscopy showed that CsI effectively showed the alpha-phase while suppressing the delta-phase, resulting in improved crystallinity and enhanced light absorption. Photoluminescence(PL) measurements demonstrated minimal peak shift(25.7 nm) over 15 minutes for CsI-based films, confirming superior phase stability compared to other bottom-layers. Consequently, perovskite solar cells incorporating CsI exhibited enhanced open-circuit voltage(VOC), short-circuit current density(JSC), and fill factor(FF), maintaining 101.1% of the initial efficiency and 99.2% of the maximum efficiency over 12 hours of maximum power point(MPP) tracking under 25℃ and 40% relative humidity without encapsulation. These findings highlight that bottom-layer engineering critically influences perovskite crystal growth, phase stability, and device performance. CsI, in particular, provides a combination of alpha-phase stabilization, high optical absorption, and superior film quality, making it an optimal bottom-layer for high-efficiency and long term stable perovkite solar cells.

Keywords
Vacuum-Deposition
Perovskite Solar Cells
Bottom-Layer Enginering
Enhancing Stability
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Information
  • Publisher :Korea Photovoltaic Society
  • Publisher(Ko) :한국태양광발전학회
  • Journal Title :Current Photovoltaic Research
  • Volume : 14
  • No :1
  • Pages :25-31
  • Received Date : 2025-10-13
  • Revised Date : 2025-11-14
  • Accepted Date : 2025-11-24
  • DOI :https://doi.org/10.21218/CPR.2026.14.1.025
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