title: An Effective Approach to Improving Cadmium Telluride (111)A Surface by Molecular-Beam-Epitaxy Growth of Tellurium Monolayer.
abstract: The surface cleansing treatment of non-natural cleavage planes of semiconductors is usually performed in vacuum using ion sputtering and subsequent annealing. In this Research Article, we report on the evolution of surface atomic structure caused by different ways of surface treatment as monitored by in situ core-level photoemission measurements of Cd-4d and Te-4d atomic levels and reflection high-energy electron diffraction (RHEED). Sputtering of surface increases the density of the dangling bonds by 50%. This feature and the less than ideal ordering can be detrimental to device applications. An effective approach is employed to improve the quality of this surface. One monolayer (ML) of Te grown by the method of molecular beam epitaxy (MBE) on the target surface with heating at 300 °C effectively improves the surface quality as evidenced by the improved sharpness of RHEED pattern and a reduced diffuse background in the spectra measured by high-resolution ultraviolet photoemission spectroscopy (HRUPS). Calculations have been performed for various atomic geometries by employing first-principles geometry optimization. In conjunction with an analysis of the core level component intensities in terms the layer-attenuation model, we propose a "vacancy site" model of the modified 1 ML-Te/CdTe(111)A (2 × 2) surface.
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.|Department of Physics, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801-3080, United States.
authors.forename: Jie
authors.initials: J
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Li
authors.initials: L
authors.lastname: Fu
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: Guang
authors.initials: G
authors.lastname: Bian
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Su
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Physics, University of California , Berkeley, California 94720, United States.
authors.forename: Saavanth
authors.initials: S
authors.lastname: Velury
authors.affiliation: Institute for Solid State Physics, University of Tokyo , Kashiwanoha, Chiba 277-8581, Japan.
authors.forename: Ryu
authors.initials: R
authors.lastname: Yukawa
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801-3080, United States.
authors.forename: Longxiang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Gangqiang
authors.initials: G
authors.lastname: Zha
authors.affiliation: State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University , Xi'an 710072, China.
authors.forename: Rongrong
authors.initials: R
authors.lastname: Guo
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801-3080, United States.
authors.forename: Tom
authors.initials: T
authors.lastname: Miller
authors.affiliation: Joseph Henry Laboratory and Department of Physics, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: M Zahid
authors.initials: MZ
authors.lastname: Hasan
authors.affiliation: Department of Physics, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801-3080, United States.
authors.forename: Tai-Chang
authors.initials: TC
authors.lastname: Chiang
keywords: 1 ML-Te/CdTe(111)A (2 × 2) surface; adlayer; atomic geometry; dangling bonds; layer-attenuation model; surface reconstruction