日盲紫外探测技术是近年来军事和民用领域的研究热点。本项目针对目前发展高Al组分AlGaN日盲雪崩光电探测器（APD）面临的关键科学问题，为了缓解AlGaN日盲APD对于AlGaN材料质量和p型掺杂效率的依赖程度，提出基于渐变组分AlGaN异质结极化诱导调控机制，发展面向日盲单光子探测的AlGaN APD构想。研究内容包括：(1)开展渐变组分AlGaN极化诱导调控异质结设计以及异质结材料质量和极化协同作用规律的研究；(2)阐释异质结中场离化激发二维空穴气的极化诱导调控机制,建立极化和能带工程调控载流子碰撞离化率的物理模型,有效提高p型AlGaN掺杂效率；(3)应用极化诱导调控异质结开展吸收区和倍增区分离的高Al组分AlGaN APD结构设计，掌握低噪音、高增益APD的关键制备技术。项目期望能够实现氮化物半导体日盲单光子探测技术的突破，为氮化物半导体光电探测技术的发展提供良好的技术支撑。

Solar-blind ultraviolet (UV) detection technology has attracted great interests in modern military and civil fields recently. This project is aimed at the key scientific issues in the development of AlGaN solar-blind avalanche photodetectors (APDs) with high-Al-content. In order to alleviate the dependence of AlGaN solar-blind avalanche photodetectors (APD) on the major problems of AlGaN material quality and p-type doping with high-Al-content, we proposed the concept of AlGaN APD for solar blind single photo detection based on the polarization-induced regulation of graded-AlGaN heterostructure. The main research contents include: (1) Carrying out the design of polarization-induced regulation of graded-AlGaN heterostructure and the synergistic effect of material quality and polarization field; (2) Explaining the polarization-induced regulation mechanism of two-dimensional hole gas excited by the field ionization, establishing combination physical model of polarization and energy-band engineering to control carrier impact ionization rate and improve the p-type AlGaN doping efficiency effectively; (3) Applying the polarization-induced graded-AlGaN heterostructure to design the separate absorption and multiplication AlGaN APD. The project finally will realize the breakthrough of nitride semiconductor solar-blind single photon detection, and provide technical support for nitride semiconductor photodetection technology.