Micro-cavity–induced optical resonance for performance enhancement in ultra-thin CdTe photovoltaic devices


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ÇOKDUYGULULAR E.

Scientific Reports, vol.16, no.1, 2026 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 16 Issue: 1
  • Publication Date: 2026
  • Doi Number: 10.1038/s41598-026-35105-4
  • Journal Name: Scientific Reports
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, MEDLINE, Directory of Open Access Journals
  • Keywords: Dielectric–metal–dielectric resonator, Optical micro-cavity, Transfer matrix method, Ultra-thin CdTe solar cell
  • Istanbul University Affiliated: No

Abstract

This study proposes a micro-cavity architecture based on the optical resonance principle to enhance photon harvesting and minimize efficiency losses due to thinning in ultra-thin CdTe-based solar cells. The cavity-free reference structure has been optimized both optically and electrically using the Transfer Matrix Method and SCAPS-1D simulations. The results revealed that a 240 nm CdTe layer provides the optimal balance between high optical absorption and efficient carrier transport. The micro-cavity structure was realized by employing a SnO2/Au/WO3 multilayer system as a dielectric/metal/dielectric resonator at the bottom interface. This configuration strengthened the electromagnetic field within the active CdTe layer, producing distinct resonance modes in the visible and near-infrared regions. As a result, the optical path length of photons increased, the average visible reflectance decreased, and photon harvesting was improved by approximately 9% under resonance conditions. Ultimately, micro-cavity integration enabled the preservation of photovoltaic performance while reducing the CdTe absorber thickness by half. This approach offers an innovative light-management strategy that balances high efficiency and low material consumption in ultra-thin film photovoltaics, establishing a strong roadmap for future semi-transparent and tandem solar cell designs.