Laser-Induced Transformations in Thermally Evaporated Thin TlInSe2 Films Studied by Raman Spectroscopy

Abstract

TlInSe2 films with thickness from 10 to 200 nm were thermally evaporated on silicon and silicate glass substrates. Micro-Raman spectra measured at a moderate excitation (532 nm, 4 kW/cm2) confirm the amorphous character of the films. Narrow features revealed in the spectra at an excitation power density of 40 kW/cm2 show the evidence for the formation of TlInSe2 , TlSe, and In2Se3 crystallites in the laser spot. For thin (10–30 nm) films, the rod-shaped TlInSe2 crystallites are shown to be oriented within the film plane. The crystallite formation is governed by the thermal effect of the tightly focused laser beam.