Moderate bandgap and high carrier mobility simultaneously realized in bilayer silicene by oxidation

Department of Applied Physics, Nanjing University of Science and Technology - Nanjing 210094, China

^(a) qianyan@njust.edu.cn (corresponding author)
^(b) mrhpwu@njust.edu.cn (corresponding author)

Received: 18 May 2020
Accepted: 24 July 2020

Abstract

Semiconductors simultaneously possessing high carrier mobility, moderate bandgap, and ambient environment stability are so important to modern industry, and Si-based semiconducting materials can match well with the previous silicon-based electronic components. Thus, searching for such Si-based semiconductors has been one hot project due to the lack of them nowadays. Here, with the help of density functional theory, we found that the full-oxidized bilayer silicene exhibits high carrier mobility with a moderate direct bandgap of 1.02 eV. The high carrier mobility is derived from the remaining of big π bond, and the moderate bandgap is opened by the saturation of dangling Si 3p bonds. Originated from the formation of strong Si-O and Si-Si bonds, the sample exhibits strong thermodynamic and dynamical stabilities. Our work indicates that the full-oxidized bilayer silicene has many potential applications in modern electronic fields.