非金属元素(F,S, Se,Te)掺杂对ZnO/graphene肖特基界面电荷及肖特基调控的理论研究

本文基于第一性原理系统研究了非金属元素F、S、Se、Te掺杂对ZnO/graphene异质结界面相互作用及其电子结构的影响。结果表明,ZnO/graphene异质结层间以范德瓦耳斯力结合形成了稳定的异质结,并且形成了n型肖特基势垒。差分电荷密度图表明graphene层的电子向ZnO层转移,使得graphene层表面带正电,ZnO层表面带负电,在界面处形成了内建电场。当掺入F原子时,异质结呈现欧姆接触;当掺入S、Se、Te原子时,异质结肖特基的接触类型均由n型转变为p型,且有效降低了肖特基势垒的高度,特别是Te原子掺入后,p型肖特基势垒高度降低至0.48 eV,提升了电子的注入效率。本文的研究结果将对相关的场效应晶体管的设计和制造提供一定的参考。

Theoretical Study on Schottky Interfacial Charge and Schottky Regulation of ZnO/Graphene by Doping of Nonmetallic Elements (F,S, Se,Te)

In this paper, the effects of F, S, Se and Te doping on the interfacial interaction and electronic structure of ZnO/graphene heterojunctions were systematically studied based on first-principles. The results show that the ZnO/graphene heterojunction layers are bonded by van der Waals force to form a stable heterojunction and an n-type Schottky barrier. The differential charge density diagram shows that the electrons of the graphene layer transfer to the ZnO layer, making the surface of the graphene layer positively charged and the surface of the ZnO layer negatively charged, forming a built-in electric field at the interface. When F atoms are added, the heterojunction presents ohmic contact. When S, Se and Te atoms are added, the contact types of the heterojunction Schottky change from n type to p type, and the height of the Schottky barrier effectively reduces, especially after Te atom is added, the height of the p type Schottky barrier reduces to 0.48 eV, which improves the electron injection efficiency. The research results of this paper will provide reference for the design and manufacture of related FET.