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Radiative recombination of confined electrons at the MgZnO/ZnO heterojunction interface.

ABSTRACT: We investigate the optical signature of the interface in a single MgZnO/ZnO heterojunction, which exhibits two orders of magnitude lower resistivity and 10 times higher electron mobility compared with the MgZnO/Al2O3 film grown under the same conditions. These impressive transport properties are attributed to increased mobility of electrons at the MgZnO/ZnO heterojunction interface. Depth-resolved cathodoluminescence and photoluminescence studies reveal a 3.2?eV H-band optical emission from the heterointerface, which exhibits excitonic properties and a localization energy of 19.6?meV. The emission is attributed to band-bending due to the polarization discontinuity at the interface, which leads to formation of a triangular quantum well and localized excitons by electrostatic coupling.

SUBMITTER: Choi S

PROVIDER: S-EPMC5547142 | biostudies-other | 2017 Aug

REPOSITORIES: biostudies-other

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Radiative recombination of confined electrons at the MgZnO/ZnO heterojunction interface.

Choi Sumin S Rogers David J DJ Sandana Eric V EV Bove Philippe P Teherani Ferechteh H FH Nenstiel Christian C Hoffmann Axel A McClintock Ryan R Razeghi Manijeh M Look David D Gentle Angus A Phillips Matthew R MR Ton-That Cuong C

Scientific reports 20170807 1

We investigate the optical signature of the interface in a single MgZnO/ZnO heterojunction, which exhibits two orders of magnitude lower resistivity and 10 times higher electron mobility compared with the MgZnO/Al<sub>2</sub>O<sub>3</sub> film grown under the same conditions. These impressive transport properties are attributed to increased mobility of electrons at the MgZnO/ZnO heterojunction interface. Depth-resolved cathodoluminescence and photoluminescence studies reveal a 3.2 eV H-band opti ...[more]

PMID: 28784987

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