Optical characteristics of Bi12SiO20 single crystals by spectroscopic ellipsometry

Isik M., Delice S., Nasser H., HASANLI N., Darvishov N. H., Bagiev V. E.

MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING, vol.120, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 120
  • Publication Date: 2020
  • Doi Number: 10.1016/j.mssp.2020.105286
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex
  • Keywords: Sillenites, Ellipsometry, Optical properties, Critical points, BI12TIO20, GROWTH, BSO
  • Middle East Technical University Affiliated: Yes


Structural and optical characteristics of Bi12SiO20 single crystal grown by the Czochralski method were investigated by virtue of X-ray diffraction (XRD) and spectroscopic ellipsometry measurements. XRD analysis indicated that the studied crystal possesses cubic structure with lattice parameters of a = 1.0107 nm. Spectral dependencies of several optical parameters like complex dielectric constant, refractive index, extinction and absorption coefficients were determined using ellipsometry experiments performed in the energy region of 1.2-6.2 eV. The energy band gap of Bi12SiO20 crystals was found to be 3.25 eV by utilizing absorption coefficient analysis. Moreover, critical point energies were calculated as 3.54, 4.02, 4.82 and 5.58 eV from analyses of the second energy derivative spectra of the complex dielectric constant.