Theoretical study of defect impact on two-dimensional MoS_2  

作　　者：Anna V.Krivosheeva Victor L.Shaposhnikov Victor E.Borisenko Jean-Louis Lazzari Chow Waileong Julia Gusakova Beng Kang Tay 

机构地区：[1]Belarusian State University of Informatics and Radioelectronics [2]CNRS, Aix-Marseille Université [3]NOVITAS, Nanoelectronics Centre of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University [4]CINTRA CNRS,NTU,THALES, Nanyang Technological University

出　　处：《Journal of Semiconductors》2015年第12期18-23,共6页半导体学报（英文版）

基　　金：supported by the Joint BRFFR-CNRS Project (No. F15F-003);the Visby Program: scholarships for PhD studies and postdoctoral research in Sweden

摘　　要：Our theoretical findings demonstrate for the first time a possibility of band-gap engineering of monolayer MoS2 crystals by oxygen and the presence of vacancies. Oxygen atoms are revealed to substitute sulfur ones, forming stable MoS2-xOx ternary compounds, or adsorb on top of the sulfur atoms. The substituting oxygen provides a decrease of the band gap from 1.86 to 1.64 eV and transforms the material from a direct-gap to an indirect-gap semiconductor. The surface adsorbed oxygen atoms decrease the band gap up to 0.98 eV depending on their location tending to the metallic character of the electron energy bands at a high concentration of the adsorbed atoms. Oxygen plasma processing is proposed as an effective technology for such band-gap modifications.Our theoretical findings demonstrate for the first time a possibility of band-gap engineering of monolayer MoS2 crystals by oxygen and the presence of vacancies. Oxygen atoms are revealed to substitute sulfur ones, forming stable MoS2-xOx ternary compounds, or adsorb on top of the sulfur atoms. The substituting oxygen provides a decrease of the band gap from 1.86 to 1.64 eV and transforms the material from a direct-gap to an indirect-gap semiconductor. The surface adsorbed oxygen atoms decrease the band gap up to 0.98 eV depending on their location tending to the metallic character of the electron energy bands at a high concentration of the adsorbed atoms. Oxygen plasma processing is proposed as an effective technology for such band-gap modifications.

关 键 词：two-dimensional crystal molybdenum disulfide band gap VACANCY OXYGEN 

分 类 号：TN304.2[电子电信—物理电子学]