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Formation of Two-dimensional Electron Gas at Amorphous/Crystalline Oxide Interfaces.

ABSTRACT: Experimentally, we found the percentage of low valence cations, the ionization energy of cations in film, and the band gap of substrates to be decisive for the formation of two-dimensional electron gas at the interface of amorphous/crystalline oxide (a-2DEG). Considering these findings, we inferred that the charge transfer from the film to the interface should be the main mechanism of a-2DEG formation. This charge transfer is induced by oxygen defects in film and can be eliminated by the electron-absorbing process of cations in the film. Based on this, we propose a simple dipole model that successfully explains the origin of a-2DEG, our experimental findings, and some important properties of a-2DEG.

SUBMITTER: Li C

PROVIDER: S-EPMC5762893 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Formation of Two-dimensional Electron Gas at Amorphous/Crystalline Oxide Interfaces.

Li ChengJian C Hong YanPeng Y Xue HongXia H Wang XinXin X Li Yongchun Y Liu Kejian K Jiang Weimin W Liu Mingrui M He Lin L Dou RuiFen R Xiong ChangMin C Nie JiaCai J

Scientific reports 20180110 1

Experimentally, we found the percentage of low valence cations, the ionization energy of cations in film, and the band gap of substrates to be decisive for the formation of two-dimensional electron gas at the interface of amorphous/crystalline oxide (a-2DEG). Considering these findings, we inferred that the charge transfer from the film to the interface should be the main mechanism of a-2DEG formation. This charge transfer is induced by oxygen defects in film and can be eliminated by the electro ...[more]

PMID: 29321497

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