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arXiv · 1009.0400

Experimental characterization of the electronic structure of anatase TiO2: Thermopower modulation

Yuki Nagao·Akira Yoshikawa·Kunihito Koumoto·Takeharu Kato·Yuichi Ikuhara·Hiromichi Ohta
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Abstract

Thermopower (S) for anatase TiO2 epitaxial films (n3D: 1E17-1E21 /cm3) and the gate voltage (Vg) dependence of S for thin film transistors (TFTs) based on TiO2 films were investigated to clarify the electronic density of states (DOS) around the conduction band bottom. The slope of the |S|-log n3D plots was -20 μV/K, which is an order magnitude smaller than that of semiconductors (-198 μV/K), and the |S| values for the TFTs increased with Vg in the low Vg region, suggesting that the extra tail states are hybridized with the original conduction band bottom.

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Yuki Nagao, Akira Yoshikawa, Kunihito Koumoto, Takeharu Kato, Yuichi Ikuhara, Hiromichi Ohta. 2010-09-02. Experimental characterization of the electronic structure of anatase TiO2: Thermopower modulation. https://doi.org/10.1063/1.3507898

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