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arXiv · 1011.3681

Field-induced water electrolysis switches an oxide semiconductor from an insulator to a metal

Hiromichi Ohta·Yukio Sato·Takeharu Kato·SungWng Kim·Kenji Nomura·Yuichi Ikuhara·Hideo Hosono
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Abstract

Here we demonstrate that water-infiltrated nanoporous glass electrically switches an oxide semiconductor from an insulator to metal. We fabricated the field effect transistor structure on an oxide semiconductor, SrTiO3, using 100%-water-infiltrated nanoporous glass - amorphous 12CaO*7Al2O3 - as the gate insulator. For positive gate voltage, electron accumulation, water electrolysis and electrochemical reduction occur successively on the SrTiO3 surface at room temperature, leading to the formation of a thin (~3 nm) metal layer with an extremely high electron concentration of 10^15-10^16 cm^-2, which exhibits exotic thermoelectric behaviour.

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Hiromichi Ohta, Yukio Sato, Takeharu Kato, SungWng Kim, Kenji Nomura, Yuichi Ikuhara, Hideo Hosono. 2010-11-16. Field-induced water electrolysis switches an oxide semiconductor from an insulator to a metal. https://doi.org/10.1038/ncomms1112

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