垂直应变对Graphene/GaN异质结肖特基势垒和光学性质的影响

Effect of Vertical Strain on Schottky Barrier and Optical Properties of Graphene/GaN Heterojunction

半导体中金-半接触时界面处的能带弯曲形成肖特基势垒。为了获取高性能微纳电子或光子器件,必须对接触处势垒高度和接触类型进行调控。文章采用密度泛函理论研究了graphene/GaN异质结的界面行为、金-半接触类型以及光学性质。研究发现,异质结中的graphene和GaN保留了各自的本征电子性质,在界面处形成肖特基接触。通过有效调控层间距、graphene/GaN异质结中肖特基势垒以及肖特基势垒类型,可实现肖特基势垒由p型向n型转变,极大地提高光吸收强度,证实了graphene/GaN异质结中肖特基接触能进行有效调控,为设计高性能微纳电子器件提供参考。

Schottky barriers are formed by energy band bending at the interface during gold-half contacts in semiconductors.To gain high performance nano-electronic or photonic device,the contact barrier height and contact type must be regulated.This paper investigates the interfacial behavior,Au-half contact type and optical properties of graphene/GaN heterojunction by using density functional theory.It is found that graphene and GaN in the heterojunction retain their respective intrinsic electronic properties and form Schottky contacts at the interface.By effectively regulating the layer spacing,the Schottky barrier in graphene/GaN heterojunction and the type of Schottky barrier,the shift of Schottky barrier from p-type to n-type can be realized and the light absorption intensity will be greatly improved,which demonstrates that Schottky contact in graphene/GaN heterojunction can be effectively regulated and provides a reference for the design of high-performance micro-and nanoelectronic devices.