Free-electronlike diffusive thermopower of indium tin oxide thin films

Abstract

We report our measurements of thermopower, S (T), on a series of indium tin oxide thin films from 300 down to 5 K to extract the carrier concentration n. The temperature behavior of S (T) below 300 K can be essentially described by a prevailing linear diffusive contribution. In this wide temperature interval, the phonon-drag thermopower is negligible relative to the diffusive thermopower. Therefore, the free-electronlike characteristic is clearly addressed. It should be stressed that linearity in S(d) from liquid-helium temperatures all the way up to room temperatures is seldom seen even in simple metals. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3524522]