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arXiv · 1009.5548

Electric field modulation of thermopower for transparent amorphous oxide thin film transistors

Hirotaka Koide·Yuki Nagao·Kunihito Koumoto·Yuka Takasaki·Tomonari Umemura·Takeharu Kato·Yuichi Ikuhara·Hiromichi Ohta
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Abstract

To clarify the electronic density of states (DOS) around the conduction band bottom for state of the art transparent amorphous oxide semiconductors (TAOSs), InGaZnO4 and In2MgO4, we fabricated TAOS-based transparent thin film transistors (TTFTs) and measured their gate voltage dependence of thermopower (S). TAOS-based TTFTs exhibit an unusual S behavior. The |S|-value abruptly increases, but then gradually decreases as Vg increases, clearly suggesting the anti-parabolic shaped DOS is hybridized with the original parabolic shaped DOS around the conduction band bottom.

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Hirotaka Koide, Yuki Nagao, Kunihito Koumoto, Yuka Takasaki, Tomonari Umemura, Takeharu Kato, Yuichi Ikuhara, Hiromichi Ohta. 2010-09-28. Electric field modulation of thermopower for transparent amorphous oxide thin film transistors. https://doi.org/10.1063/1.3512870

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