On the passivation performance of SiNx, SiOxNy and their stack on c-Si wafers for solar cell applications: Correlation with optical, chemical and interface properties

Canar H. H., Bektaş G., Turan R.

SOLAR ENERGY MATERIALS AND SOLAR CELLS, cilt.256, 2023 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 256
  • Basım Tarihi: 2023
  • Doi Numarası: 10.1016/j.solmat.2023.112356
  • Dergi Adı: SOLAR ENERGY MATERIALS AND SOLAR CELLS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Environment Index, Greenfile, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Fixed charge density, Hydrogen, Interface state density, Silicon nitride, Silicon oxynitride, Surface passivation
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

SiNx and SiOxNy layers deposited by the PECVD method are commonly used in silicon solar cells for their excellent thin film properties. In this study, we perform an experimental analysis of the optical, chemical and electrical properties of these films prepared under different process conditions. The C-V measurements for the interface analysis reveal that SiOxNy layers for any refractive index have lower interface state density and fixed charge density than SiNx layers. Additionally, our calculations on the FTIR spectra indicate that SiNx, when compared with SiOxNy, has a significantly higher hydrogen amount which is important in reducing the interface traps. Furthermore, we explain the passivation results obtained from PCD measurement for single SiNx, single SiOxNy and their stack layers on p-type and n-type Si wafers by C-V and FTIR measurements. Our results suggest that depositing a very thin SiOxNy having low Dit beneath SiNx having high Qf and H amount provides superior passivation on p and n-type Si wafers, which is improved further by a subsequent fast-firing process.