Dataset Information

Transport Properties and Finite Size Effects in ?-Ga2O3 Thin Films.

ABSTRACT: Thin films of the wide band gap semiconductor ?-Ga2O3 have a high potential for applications in transparent electronics and high power devices. However, the role of interfaces remains to be explored. Here, we report on fundamental limits of transport properties in thin films. The conductivities, Hall densities and mobilities in thin homoepitaxially MOVPE grown (100)-orientated ?-Ga2O3 films were measured as a function of temperature and film thickness. At room temperature, the electron mobilities ((115?±?10)?cm2/Vs) in thicker films (>150?nm) are comparable to the best of bulk. However, the mobility is strongly reduced by more than two orders of magnitude with decreasing film thickness ((5.5?±?0.5)?cm2/Vs for a 28?nm thin film). We find that the commonly applied classical Fuchs-Sondheimer model does not explain sufficiently the contribution of electron scattering at the film surfaces. Instead, by applying an electron wave model by Bergmann, a contribution to the mobility suppression due to the large de Broglie wavelength in ?-Ga2O3 is proposed as a limiting quantum mechanical size effect.

SUBMITTER: Ahrling R

PROVIDER: S-EPMC6739305 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Transport Properties and Finite Size Effects in β-Ga2O3 Thin Films.

Ahrling Robin R Boy Johannes J Handwerg Martin M Chiatti Olivio O Mitdank Rüdiger R Wagner Günter G Galazka Zbigniew Z Fischer Saskia F SF

Scientific reports 20190911 1

Thin films of the wide band gap semiconductor β-Ga2O3 have a high potential for applications in transparent electronics and high power devices. However, the role of interfaces remains to be explored. Here, we report on fundamental limits of transport properties in thin films. The conductivities, Hall densities and mobilities in thin homoepitaxially MOVPE grown (100)-orientated β-Ga2O3 films were measured as a function of temperature and film thickness. ...[more]

PMID: 31511538

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Dataset Information

Transport Properties and Finite Size Effects in ?-Ga2O3 Thin Films.

Publications

Transport Properties and Finite Size Effects in β-Ga<sub>2</sub>O<sub>3</sub> Thin Films.

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