垂直有序GaN基纳米LED阵列制备及其光机电耦合特性研究

Wurtzite GaN-based nanomaterials have excellent optoelectronic, piezoelectric and mechanical performances. Accordingly, research and utilization of optical-mechanical-electronic coupling characteristics will be beneficial to development and applications of GaN-based nanomaterials and nanodevices. In this program, we adopt both top-down nanopatterning template and bottom-up MOCVD selective area epitaxy to fabricate controllable InxGa1-xN nanodisk embeded nanoLED ordered arrays, including shape, size, density, alignment and In content. At first, we emphatically analyze effects of defects, etching damage and passivation,nanostructures on optical, electrical, mechanical properties of multicolor GaN-based nanoLEDs. In addition, we investigate modulation behaviors of mechanical pressure/deformation on carrier transpot and photoelectric recombination processes of GaN-based nanoLEDs. Through the establishment of piezoelectric potential model of GaN-based nanoLEDs, the optical-mechanical-electronic coupling characteristics and mechanisms of vertically ordered GaN-based nanoLEDs will be fully clarified. Finally, high-quality and highly-ordered GaN-based nanoLED array device will be sucessfully developed. And it can be used to achieve the high-resolution electroluminescent imaging of pressure distribution. Therefore, the program implementation will promote the potential applications in micro/nano optical microelectromechanical systems, human-machine interface, consumer electronics, high-density information communications, environmental monitoring, self-power sensing and so on.

纤锌矿GaN基纳米材料具有优异的光电、压电和机械特性，针对其新颖的光机电多场耦合特性的研究与利用，将有利于促进GaN基纳米光电材料及其新型传感器件的开发和应用。本项目将采用自上而下的纳米图形化刻蚀和自下而上的MOCVD选区外延生长相结合方法，来制备形状、尺寸、密度、取向和组分可控的InxGa1-xN纳米盘嵌入式纳米LED阵列材料，深入分析材料缺陷、刻蚀损伤及钝化修复、纳米结构参数对GaN基纳米LED的光学、电学和力学特性的影响，探究外界压力/形变对GaN基纳米LED中载流子输运和光电复合过程的调控机制，并通过GaN基纳米LED压电势理论模型的建立，揭示并阐明GaN基纳米LED中的光机电多场耦合特性，最终研制出高质量、高有序的GaN基纳米LED阵列发光器件，并实现压力分布的高分辨传感成像，这将有助于促进微纳光机电系统、人机交互、消费电子、高密度信息通信、环境监测、自驱动传感等领域的应用。

结合其压电和半导体双重物理性质，纤锌矿型GaN基纳米材料和结构展现出新颖的光机电多场耦合特性。本项目利用微纳精细加工和选区外延生长技术的互补优势，制备得到了垂直有序的InxGa1-xN纳米盘嵌入式纳米LED阵列材料，实现了其形状、尺寸、密度和极性取向的精确可控。并研究了基于三维GaN基纳米LED结构的光学、电学和力学特性规律，实验观察得到了外界压力/形变对其载流子输运和光电复合过程的调控机制，获得了GaN基纳米LED中的光机电多场耦合特性。并将压电-光电耦合效应应用于压力成像中，构建出GaN基纳米LED压力传感阵列器件原型，并成功实现了高分辨压力传感成像。本项目提出的空间压力可视化成像技术串扰小、误码率低、分辨率逼近光学衍射极限，且具有快速实时、均匀可靠的成像特点，其研究成果将为空间应力/应变分布提供全方位分析途径。通过本项目的支持和实施，研究团队共发表研究论文8篇，申请国家发明专利6项，培养出站博士后1名，培养毕业博士研究生1名，硕士生5名。主要取得了以下成果：.（1）开发完成大面积微纳尺寸的有序阵列制作关键工艺；.（2）完成GaN基微纳结构阵列成像器件研制；.（3）综合表征GaN基微纳结构单元的电学、光学和力学性能；.（4）研究力-电-光耦合作用下应力/应变调控光致发光特性及其调控原理；.（5）并行多像素实时高分辨率应力/应变分布成像；.（6）拓展GaN基体系光-机-电多场耦合应用，如柔性可穿戴光电开关和光开关等.总之，本项目团队通过团结协作和努力，圆满完成了研究目标。