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arXiv · 0804.0443

Anomalously large measured thermoelectric power factor in Sr$_{1-x}$La$_x$TiO$_3$ thin films due to SrTiO$_3$ substrate reduction

Matthew L. Scullin·Choongho Yu·Mark Huijben·Subroto Mukerjee·Jan Seidel·Qian Zhan·Joel Moore·Arun Majumdar·R. Ramesh
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Abstract

We report the observation that thermoelectric thin-films of La-doped SrTiO3 grown on SrTiO3 substrates yield anomalously high values of thermopower to give extraordinary values of power factor at 300K. Thin-films of Sr0.98La0.02TiO3, grown via pulsed laser deposition at low temperature and low pressure (450C, 10-7Torr), do not yield similarly high values when grown on other substrates. The thin-film growth induces oxygen reduction in the SrTiO3 crystals, doping the substrate n-type. It is found that the backside resistance of the SrTiO3 substrates is as low (~12ohm/square) as it is on the film-side after film growth.

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Matthew L. Scullin, Choongho Yu, Mark Huijben, Subroto Mukerjee, Jan Seidel, Qian Zhan, Joel Moore, Arun Majumdar, R. Ramesh. 2008-04-07. Anomalously large measured thermoelectric power factor in Sr$_{1-x}$La$_x$TiO$_3$ thin films due to SrTiO$_3$ substrate reduction. https://doi.org/10.1063/1.2916690

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