应变对单层/少层MoS2纳米片及其器件的性能的影响

单层/少层MoS2由于其二维结构和半导体特性在纳米电子和光电器件、太阳能、催化、自旋和量子器件等领域都有巨大潜力。理论研究显示，应变会改变单层/少层MoS2的能带结构和带隙，从而影响其电学和光学特性。但是，目前这方面的实验研究还极少，已有的理论研究也有相互矛盾。本项目致力于研究应变影响单层/少层MoS2及其器件的电学、光学和光电性能的规律；回答能否通过应变提高MoS2晶体管的电学和光电性能的问题；探索MoS2在应变传感器、可变波长可见光和红外探测器方面的潜力；探索新原理、新结构器件。将以可控环境下系统、定量的实验研究为主，结合理论计算。主要研究：单层/少层MoS2的PL谱随片层内单轴应变的变化；基于单层/少层MoS2的场效应晶体管在应变下载流子迁移率和亚阈值斜率等性能的变化规律；基于单层/少层MoS2的纳米器件的光电性能随应变的变化规律；探索利用上述规律构建新原理、新结构的高性能纳米器件。

Due to their 2D structure and semiconducting properties, single- and few-layer MoS2 have great potential in nano electronic and photoelectronic devices, solar cell, catalyse, spin and quantum devices, etc. Theoretical studies propose strain can change the energy band structure and bandgap of single- and few-layer MoS2, therefore can change their electronic and photoelectronic properties. However, so far, experimental study in this field is rare, and theoretical works have inconsistency. This project is aimed to study the influence of strain to the electronic, optical and photoelectronic properties of single- and few-layer MoS2 and their devices. We would like to answer whether strain can enhance the electronic and photoelectronic properties of MoS2 transistors. We will pursue the potential of MoS2 in strain-sensor, as well as in visible and infrared photodetectors. We will also pursue devices based on new mechanism and new structures. Systematic and quantitative experiments in controlled environments will be performed. Theoretical study will also be done. The project will mainly study the following issues. How the PL spectrum of single- and few-layer MoS2 changes with single-axis strain inside the layer. How strain changes the mobility and subthreshold slope of FETs based on single- and few-layer MoS2. How strain changes the photoelectronic properties of single- and few-layer MoS2 nanodevices. How to realize high performance nanodevices based on the above findings.