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

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.