Electrical and optical properties of n-type InSb thin films

Abstract

The n-type indium antimonide thin films of the thickness 900 nm have been fabricated by electron beam evaporation technique on ultrasonically cleaned glass substrates at different temperatures (298 K–473 K) using optimized source material. The electrical and optical properties of these films have been studied and optimized the film deposition temperature. The electrical resistivity decreases (1.50-0.25)×10^-3 ohm.cm with increase of temperature up to 398 K. The Hall Effect measurement indicates that the films are n-type semiconductor having carrier concentration (0.100.040)×10¹⁸ cm^-3 and mobility (3.03-53.20)×10⁴ cm²/Vs. The type of semiconductivity has also been confirmed by TEP measurement. The direct band gap has been calculated by Fourier Transform Infrared (FTIR) transmission spectra recorded at room temperature. The direct band decreases from 0.195 to 0.180 eV with increase of substrate temperatures (298 K-473 K). The carrier concentration 0.040×10¹⁸ cm^-3_, Hall mobility 53.20×10⁴ cm²/Vs, electrical resistivity 0.25 ×10^-3 ohm.cm and direct band gap 0.18 eV have been observed for n-InSb film of 900 nm thick deposited at 398 K.