title: The isotype ZnO/SiC heterojunction prepared by molecular beam epitaxy--A chemical inert interface with significant band discontinuities.
abstract: ZnO/SiC heterojunctions show great potential for various optoelectronic applications (e.g., ultraviolet light emitting diodes, photodetectors, and solar cells). However, the lack of a detailed understanding of the ZnO/SiC interface prevents an efficient and rapid optimization of these devices. Here, intrinsic (but inherently n-type) ZnO were deposited via molecular beam epitaxy on n-type 6H-SiC single crystalline substrates. The chemical and electronic structure of the ZnO/SiC interfaces were characterized by ultraviolet/x-ray photoelectron spectroscopy and x-ray excited Auger electron spectroscopy. In contrast to the ZnO/SiC interface prepared by radio frequency magnetron sputtering, no willemite-like zinc silicate interface species is present at the MBE-ZnO/SiC interface. Furthermore, the valence band offset at the abrupt ZnO/SiC interface is experimentally determined to be (1.2 ± 0.3) eV, suggesting a conduction band offset of approximately 0.8 eV, thus explaining the reported excellent rectifying characteristics of isotype ZnO/SiC heterojunctions. These insights lead to a better comprehension of the ZnO/SiC interface and show that the choice of deposition route might offer a powerful means to tailor the chemical and electronic structures of the ZnO/SiC interface, which can eventually be utilized to optimize related devices.
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Nanying
authors.initials: N
authors.lastname: Lin
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Huiqiong
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Physical Science and Technology, Xiamen University (XMU), Xiamen, China.
authors.forename: Junyong
authors.initials: J
authors.lastname: Kang
authors.affiliation: Renewable Energy, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), Berlin, Germany.|Energy Materials In-Situ Laboratory Berlin (EMIL), Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany.
authors.forename: Regan
authors.initials: R
authors.lastname: Wilks
authors.affiliation: Renewable Energy, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), Berlin, Germany.|Energy Materials In-Situ Laboratory Berlin (EMIL), Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Berlin, Germany.|Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus-Senftenberg, Cottbus, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Bär
authors.affiliation: School of Aerospace Engineering, Xiamen University (XMU), Xiamen, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Mu