期刊
2D MATERIALS
卷 5, 期 4, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.1088/2053-1583/aad1b7
关键词
molybdenum disulfide; gallium nitride; 2D/3D heterojunctions; TEM; Schottky barrier; contacts to 2D; p-GaN
资金
- US Army Research Laboratory (ARL) Director's Strategic Initiative (DSI) program
- DOD High Performance Computing Modernization Program at the US Air Force Research Laboratory
- US Army Engineer Research and Development Center DoD Supercomputing Resource Centers
- National Science Foundation [DMR-1453924]
- DOD High Performance Computing Modernization Program at the US Army Engineer Research and Development Center DoD Supercomputing Resource Centers
- Material Genome Initiative
A promising approach for high speed and high power electronics is to integrate two-dimensional (2D) materials with conventional electronic components such as bulk (3D) semiconductors and metals. In this study we explore a basic integration step of inserting a single monolayer MoS2 (1L-MoS2) inside a Au/p-GaN junction and elucidate how it impacts the structural and electrical properties of the junction. Epitaxial 1L-MoS2 in the form of 1-2 mu m triangle domains are grown by powder vaporization on a p-doped GaN substrate, and the Au capping layer is deposited by evaporation. Transmission electron microscopy (TEM) of the van der Waals interface indicates that 1L-MoS2 remained distinct and intact between the Au and GaN and that the Au is epitaxial to GaN only when the 1L-MoS2 is present. Quantitative TEM analyses of the van der Waals interfaces are performed and yielded the atomic plane spacings in the heterojunction. Electrical characterization of the all-epitaxial, vertical Au/1L-MoS2/p-GaN heterojunctions enables the derivations of Schottky barrier heights (SBH) and drawing of the band alignment diagram. Notably, 1L-MoS2 appears to be electronically semi-transparent, and thus can be considered as a modifier to the Au contact rather than an independent semiconductor component forming a pn-junction. The I-V analysis and our first principles calculation indicated Fermi level pinning and substantial band bending in GaN at the interface. Lastly, we illustrate how the depletion regions are formed in a bipolar junction with an ultrathin monolayer component using the calculated distribution of the charge density across the Au/1L-MoS2/GaN junction.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据