Accurate Determination of the Temperature Dependence of the Refractive Index of 4H-SiC at the Wavelength of 632 nm

Abstract:

The growing interest for the use of 4H-SiC in photonics is triggering the interest for more accurate characterizations of this semiconductor from the optical and opto-electronic point of view. In this work we report about new measurements run on an undoped 4H-SiC substrate, finalized at determining the precise dependence of its refractive index on temperature in the visible spectrum, and precisely at the wavelength of λ=632.8 nm, in a temperature range from room temperature (RT) to 400K. Measurements are performed by exploiting the properties of a Fabry-Perot cavity interrogated with a laser beam. It is known that the transmitted radiation intensity shows fringes that shift with temperature and the refractive index. By precisely monitoring the transmitted signal, the thermo-optic coefficient dn/dT can be determined with a resolution that approaches 10^-6 K^-1.

• Periodical: Materials Science Forum (Volume 1089)
• Pages: 81-85
• DOI: https://doi.org/10.4028/p-9j6d42
• Online since: May 2023
• Authors: Elisa Demetra Mallemace*, Sandro Rao, Maurizio Casalino, Mario Iodice, Giuliana Faggio, Giacomo Messina, Francesco Giuseppe Della Corte
• Keywords: Refractive Index, Temperature Dependence, Thermo-Optic Coefficient

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