Determination of the Optical Properties of ZnSe Thin Films Using the Transfer Matrix Method

The transfer matrix method (TMM) is presented as a highly effective alternative in the treatment of problems of electromagnetic wave propagation through stratified media. This method allows to determine the transmission and reflection coefficients of the system. In this paper the TMM is applied to simulate the experimental transmittance spectra of ZnSe thin films prepared with high vacuum evaporation. From the simulation the spectral variation of the refractive index, the absorption coefficient and material gap of the ZnSe were obtained. The TMM was applied to a series of samples prepared at substrate temperatures between (200 and 350)°C. Absorption coefficients values in the order of 10⁻³ cm⁻¹ were found in the high absorption region while the refractive index was around 2.7 at λ = 600 nm. The material gap found for all the samples was about 2.65 eV