极化增强的AlGaN日盲雪崩光电探测器研究

项目名称： 极化增强的AlGaN日盲雪崩光电探测器研究

项目编号： No.61474060

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 陈敦军

作者单位： 南京大学

项目金额： 84万元

中文摘要： 日盲紫外探测技术无论是在军事还是民用领域都有着极其重要的应用。本申请项目将重点针对目前发展AlGaN日盲紫外探测器存在的关键问题，挖掘材料的固有禀性，提出极化增强的雪崩光电探测器构想，以期通过利用氮化物半导体异质结构强极化特性，设计和制备出具有极化增强效应的雪崩探测器结构，缓解器件对高晶体质量的高Al组份AlGaN材料制备和p型掺杂两大难题的依赖程度，并依此深入研究基于AlGaN模板上的AlGaN异质结构外延过程中应力的调控作用，应力-位错-极化的物理关系模型，极化效应对异质界面能带带阶的调制和对载流子碰撞离化率的影响，实现雪崩光电探测器中应力和极化的综合调控，达到提高探测器雪崩增益和降低器件暗电流等目的。建立起器件性能与器件结构、材料、工艺等参数之间的关联模型，形成一套基于极化和应力调控的具有高雪崩增益的AlGaN基日盲紫外雪崩探测器设计理论。

中文关键词： 铝镓氮半导体；雪崩光电探测；日盲；极化

英文摘要： Solid-state avalanche photodiodes (APDs) based on AlGaN are intrinsically solar-blind, in which no additional filters are needed, and could be a viable alternative to current bulky and fragile photomultiplier tubes.AlGaN APDs have outstanding advantages such as lower operation voltages, lower power consumption, smaller sizes, and no need for cooling, which are suitable for integration into space shuttles, satellites, and some military vehicles.This project proposes a new AlGaN APD structure with polarization enhanced characteristic in order to alleviate the difficulties of the state-of-the-art growth and p-type doping of high-Al-composition AlGaN alloys.This ideal can be realized by adjusting Al composition discrepancy in different AlGaN layers and hence introducing a polarization electric field with the same direction as applied reverse-bias electric field in multiplication region of APDs.We will focus our interests on how to control synergistically lattice mismatch stress and polarization field when fabricating different AlGaN heterostructures and how to build the physical model of stress-dislocation-polarization.Meanwhile, the effects of polarization on the energy band structure and carrier impacting inonization of AlGaN device structure will be also investigated.Based on these research results, we will design and fabricate optimally the polarization enhanced AlGaN solar-blind APDs and study their performances and device physics systemically.

英文关键词： AlGaN semiconductor;alvalanche photodiodes;solar-blind;polarization