Location sensitive photodetectors based on strained 2D materials

应变半导体通常被认为是改善未来器件电子性能的手段。例如，应变硅可以表现出更高的迁移率，并且已经被强调为CMOS持续小型化的关键特征。与块状材料相反，在块状材料中，应变是由预定的晶格不匹配生长产生的，并且限制在低应变范围内，原子薄材料可以维持明显更高的应变水平，因为它们的面积与厚度长宽比大，使得它们的电子特性的变化更加明显。这个项目的目的是双重的。首先，它试图在应变TMDCs中产生电荷载流子动力学的理解。特别地，研究了TMDC薄片内以及边缘和界面附近电荷的捕获和发射特性。第二个目标是开发一种基于应变的大面积TMDC薄膜的改进电阻抗的传感平台。该项目将使用扫描探针测量的组合来量化载流子浓度、陷阱态浓度及其能量分布。根据在这些实验中收集到的知识，设想将出现一个完整的材料静电图，该图将用于制作位置敏感光电探测器的原型。

Strained semiconductors are often regarded as means to improving the electronic properties of future devices. For example, strained silicon can exhibit increased mobility and has been highlighted as a key feature in continued miniaturisation of CMOS. In contrast to bulk materials, where strain is produced by lattice-mismatched growth that is predetermined and limited to low strains, atomically-thin materials can sustain significantly higher strain levels, due to their large area-to-thickness aspect ratio, making the changes to their electronic properties more pronounced. The aim of this project is twofold. First, it seeks to generate an understanding of charge carrier dynamics within strained TMDCs. In particular, the capture and emission properties of charges within TMDC flakes and in the vicinity of edges and interfaces. The second aim is to develop a sensing platform that is based on the modified electrical impedance of strained, large area TMDC films. The project will use a combination of scanning probe measurements to quantify the carrier concentration, the concentration of trap states and their energy distribution. It is envisaged that a full electrostatic map of the materials will emerge which will be utilised to prototype a location sensitive photodetector based on the knowledge gathered in these experiments.