X‐ray photoelectron spectroscopy characterization of band offsets of MgO/Mg2Si and SiO2/Mg2Si heterojunctions. (16th July 2021)

• Record Type: Journal Article
• Authors: Liao, Yangfang; Xie, Jing; Lv, Bing; Xiao, Qingquan; Xie, Quan
• Is Part Of: Surface and interface analysis. Volume 53:Number 10(2021)
• Page Start: 852
• Page End: 859
• Publication Date: 2021-07-16
• Subjects: band bending -- band offset -- heterojunction -- MgO/Mg2Si -- SiO2/Mg2Si; Surfaces (Physics) -- Periodicals; Surface chemistry -- Periodicals; Thin films -- Periodicals; 541.33
• DOI: 10.1002/sia.6986
• Languages: English
• ISSNs: 0142-2421

Abstract

Abstract : MgO and SiO2 are the natural oxide layer on the surface of Mg2 Si and the excellent gate dielectric layer materials. MgO/Mg2 Si and SiO2 /Mg2 Si heterojunctions were successfully prepared by magnetron sputtering. The valence band offset (VBO) and conduction band offset (CBO) of the two heterojunctions were measured by X‐ray photoelectron spectroscopy (XPS) method, and the values were 2.64 and 3.90 eV for MgO/Mg2 Si and 3.24 and 4.43 eV for SiO2 /Mg2 Si, respectively. Different degree of band bending occurs on the two interfaces. As a result, the band diagrams of the both interfaces are all Type‐I (Straddled) band alignment. Such high VBO and CBO can provide suitable barrier heights for both electrons and holes (>1 eV); therefore, both MgO and SiO2 can be suitable candidates for the preparation of Mg2 Si‐based thin film transistors.