二维InSe的电子和光学性质、界面工程和器件性能

A high-quality two dimensional (2D) InSe field effect transistor (FET) was first reported at the end of 2016, and the father of graphene Prof. Geim is one of the participants of this work. 2D InSe is a wide-band-gap semiconductor with high carrier mobilities at room temperature, which makes it extremely promising in the high-speed electronic and optoelectronic applications. We plan to investigate the basic electronical and optical properties of monolayer and multilayer InSe, such as quasiparticle band structure, optical absorption spectrum and exciton binding energy with inclusion of the electron-hole interaction, and then modulate their properties by strain, electric filed, and defect engineering. Metal electrode contacts in 2D material devices affect the device performance significantly. We plan to study the interfacial properties of 2D InSe contacted with different traditional bulk metals and calculate their Schottky barrier heights (SBHs) by using ab initio electronic calculations and quantum transport simulations. Subsequently, substantial efforts such as using 2D material as a buffer layer or high (or low) work function 2D metals as electrodes will be devoted to decrease or even demolish the Schottky barrier in 2D InSe devices. We will simulate sub-10 nm 2D InSe Schottky barrier FETs with different metal electrodes (3D metals, 2D metals, and 3D-2D hybrid contacts) and metal-oxide-semiconductor FETs (MOSFETs). We will compare their performances with those of Si Fin, carbon nanotube and other 2D material FETs, and find whether 2D InSe could compete with them and whether the upper performance limit of 2D InSe devices can meet the International Technology Roadmap for Semiconductors (ITRS) in the next 10 years. And we will evaluate the different electrode contacts through the performance and contact resistance of their corresponding Schottky barrier FETs.

2016年底厚度低至单层的二维InSe晶体管被制备出来。二维InSe是能隙随层数可调的半导体，具有较高的室温迁移率，在高速电子器件和光电器件上十分具有应用前景。我们计划研究二维InSe的基本电子和光学性质，如准粒子能隙、考虑激子效应的光吸收谱、激子束缚能，以及应力、电场和缺陷工程下其性质的响应规律。二维材料器件中金属电极接触的质量对器件性能的影响起着决定性的作用。拟研究二维InSe与常见传统块材金属的界面性质，利用能带分析和量子输运模拟得到半导体-金属界面处的肖特基势垒高度。接下来希望通过二维材料插层或二维金属直接与InSe接触来降低肖特基势垒高度。最后，我们拟研究亚10 nm二维InSe采用不同金属电极时肖特基势垒晶体管和金属氧化物半导体场效应管的性能表现，并与鳍状硅、碳纳米管和其他二维材料器件进行对比，看其能否与它们竞争，以及能否满足国际半导体线路图未来10年的需求。

2016年底，高品质的原子级厚度InSe晶体管被成功制备出来。二维InSe室温迁移率达103 cm2 V-1s-1，因此，在高速电子器件和光电器件上十分具有应用前景。本项目启动时，关于二维InSe的研究仍处于非常初始的阶段。我们从第一性原理方法出发，研究了二维InSe的基本电子和光学性质，模拟了亚10 nm二维InSe MOSFET器件的性能，并和国际半导体线路图进行了比较。我们研究了锂在层状InSe上的吸收和扩散性质。我们采用第一性原理方法，结合双界面模型和输运理论，系统地研究了单层和双层InSe场效应晶体管中不同电极的接触性质。我们关于低维材料接触性质的研究成果受到国际同行的认可，在国际知名综述杂志Reports on Progress in Physics上撰写了相关的综述文章“Schottky barrier heights in two-dimensional field-effect transistors: from theory to experiment”，该论文已经通过初审。我们还研究了其他二维材料如黑砷磷、BiN、砷烯、锑烯、GeSe等和异质结构在电子和光电器件上的应用和电极设计。由于在新型器件方面的积累，受邀为自然电子杂志Nature Electronics撰写评论文章“Repairable integrated circuits for space”。