Tuning of structural, morphological, optical and electrical properties of SnO 2 by indium inclusion

A complete range of indium-doped (In:SnO 2 ) thin films prepared by spray-pyrolysis technique have been studied and characterized by different techniques to get information about structure, surface and electrical properties. The influence of indium filler concentration (i.e., 0–15 wt%) on the properties of SnO 2 has been explored. Structural study reveals that the inclusion of indium after a certain optimum value leads structural distortion which causes the films’ expansion along c-axis direction. The extract of electrical study helps to understand that what should be the optimum value to switch from n- to p-type, which is further confirmed by Hall measurement. A deep analysis of electrical data confirms that the solid solution of indium into SnO 2 should not be completely excluded and its range should not be >12 wt% as we got saturation in the electrical behaviour after it. Variable range hopping mechanism has been found to be best fitted for low temperature range and comes out with valuable information that increase in density of states near Fermi level are responsible for decrease in resistivity in case of higher doping and also confirms that 6 wt% is the optimum value to switch from n- to p-type conductivity.