利用高质量AlN构建真空紫外探测单元和线阵器件

Vacuum-Ultraviolet (VUV) light (10-200nm) detector, a required key device for national defense and economy construction, is promising for applications in the fields of space defense and geospace sciences. Currently, the mature VUV detection mostly draws support from satellite systems consisted of the Rowland spectrograph with microchannel plate detector. Such instruments, however, requiring thousands of operating voltage, are huge and ponderous, thus not only increasing the working load of satellite but also running up the cost of launching. Therefore, to overcome these obstacles and improve existing applications of VUV detection, a diminutive, convenient, and low power-consumption VUV sensor needs to be developed. Ultra-wide band gap semiconductor AlN (Eg=6.2eV, ca. 200nm), is an ideal material and is expected to be assembled into the required VUV sensor. However, the lack of high quality bulk materials or thin films of AlN results in reported AlN-based VUV photodetector with slow response speed. As well know as, compared with thin-film and bulk structures, micro/nanostructures are usually defect-free, making them have high crystalline quality. In addition, their low-dimensional conductive channel could confine the active area of charge carrier and shorten the transit time. In this research plan, we propose a linear array detector for vacuum-ultraviolet light based on AlN microwire single crystal, whose key lies in growing high crystalline and uniform size AlN microwires by improved PVT method and then preparaing linear array VUV detector using microfluidic technology. The core meaning of this research is explore new method and path to construct toutility devices using micro-/ nano-materials.

真空紫外(10-200nm)探测器在太空防御和空间科学领域具有重要应用需要，是国防建设和宇宙探索急需的器件。目前真空紫外探测主要依赖基于微通道板的罗兰色谱仪，该系统笨重、工作电压高，给其在卫星应用带来困难。因此，亟需研制轻便低功耗且具有成像功能的半导体基线/面阵探测器。AlN具有合适的带隙6.2eV是制备半导体基真空紫外探测器的首选材料。然而，目前高结晶质量AlN单晶很难获得，无法实现高的真空紫外探性能，更无法实现线阵或面阵探测。本申请提出：利用AlN微米线单晶(容易实现高结晶质量，另外高比表面积和低维有效导电通道能大幅提光电探测性能)制备具有成像功能的真空紫外线阵探测器。研究内容是使用改进的PVT生长方法大量合成高质量、尺寸均一的AlN微米线，并使用微流控技术将其构建出规则的线阵列。该申请的核心意义在于探索将微/纳米材料构建成可实用器件的新方法和路径。

自2017年起，申请人自主搭建了国内首个涵盖真空紫外光电材料表征和器件检测的测试平台，包含了真空紫外显微荧光测试系统(190-600 nm)，真空紫外自由光路荧光测试系统(160-900 nm)，真空紫外阴极荧光测试系统(50-400 nm)，真空紫外瞬态荧光寿命测试系统(120-980 nm, 皮秒到秒)，真空紫外光谱响应测试系统(120-400 nm)，真空紫外脉冲光电响应测试系统(157 nm, 193 nm, 纳秒脉冲)；在平台基础上，申请人从生长高质量AlN晶态材料出发，发明了首个光伏型真空紫外探测器，在此基础上，申请人进一步实现了硅集成的真空紫外成像线列器件；同时，在细致的器件测试分析过程中，我们发现了真空紫外器件中存在的正温度效应（提升温度可以协同提升真空紫外光伏器件的开关时间和光电流的转换量子效率），准费米能级劈裂增强效应（实现了当前单结最高的开路电压2.45伏的输出），和近真空紫外非周期振荡发射（来源于AlN在260 nm波长一下的强色散关系）等新的实验现象。围绕上述研究，以第一作者或通信作者发表22篇期刊论文，包括iScience、 Advanced Materials、Advanced Functional Materials、ACS Nano、Advanced Optical Materials、Advanced Electronic Materials、ACS Photonics等。其中一篇第一作论文入选ESI热点论文(前1 ‰)，两篇第一作者论文入选ESI高被引论文(前1 %)。做会议特邀报告2次，授权发明专利1项。