Effect of selenium doping on structural and optical properties of SnS:Se thin films by electron beam evaporation method

¹ Department of Physics, Manonmaniam Sundaranar University, Tirunelveli 627 012, Tamil Nadu, India
² Department of Physics, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu, India
³ CISL, Department of Physics, Annamalai University, Annamalai Nagar 608 002, Tamil Nadu, India

^a e-mail: kmohanraj.msu@gmail.com

Received: 6 September 2012
Revised: 16 November 2012
Accepted: 22 November 2012
Published online: 14 January 2013

Abstract

SnS nanoparticle has been synthesized initially using SnCl₂ · 2H₂O and Na₂S · XH₂O, in the presence of TEA by precipitation method and XRD and FTIR techniques have been used for characterization of the sample. Powder X-ray diffraction studies revealed the particle size to be 48 nm and the pattern represents polycrystalline herzenbergite orthorhombic crystal structure of SnS. The FTIR result also confirmed the SnS at 2354 cm⁻¹. Secondly SnS:Se thin films have been deposited on glass substrates by electron beam evaporation technique and the films were annealed at 100 °C and 200 °C for 1 h. The unannealed films are amorphous in nature and the annealed film shows that a sharp crystalline peak is due to SnS. Also a peak is shown at 2θ = 14.39°, which is due to characteristic peak of SnSe₂, established by their XRD patterns. The band gap energy (E_g) was determined from transmission spectra and an optical band gap of E_g varies from 1.6 eV to 1.79 eV.