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

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 نشر من قبل Hiromichi Ohta
 تاريخ النشر 2010
  مجال البحث فيزياء
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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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