Collaborative Research: Fundamental Studies of the Properties of B-III-N Wide-Bandgap Semiconductor Alloys

非技术描述：该合作研究项目研究了一种未被探索的半导体材料系统，该系统涉及BAlGaN四元素合金中的硼结合。这些材料是新一代的III-V合金系统相比，已开发的AlInGaN合金，以提供高效率的照明。基于AlInGaN合金的固态照明和照明技术在汽车、液晶显示器后面板、移动的通信和标志照明中得到了广泛的实际应用，并将很快在普通照明中占据主导地位。 然而，对于AlInGaN合金材料仍然存在重要的限制。该研究项目探讨了将硼掺入这些合金中的优势，最终目标是在异质结构中实现更好的应变匹配，在新合金系统中实现更高的效率和潜在的p型掺杂。该研究与教育活动相结合，包括研究生和本科生在这些新材料的生长，表征和处理方面的研究培训，以及格鲁吉亚理工学院和亚利桑那州立大学的各种推广计划。技术描述：该研究项目的主要重点是研究物理，化学，和电子性能的高品质薄膜的含硼III-氮化物半导体三元和四元合金在技术上重要的组成范围，并发展基础材料科学的深入了解，以改善光电器件的设计。该研究团队使用先进的金属有机化学气相沉积（MOCVD）外延薄膜生长系统，并对生长条件，衬底材料，衬底取向和掺杂的影响进行了深入研究。使用最先进的纳米级表征工具的材料性能进行了详细研究：使用原子分辨率像差校正的透射电子显微镜的晶体结构进行了研究;电子能带结构由电子全息确定;和光学性能测量阴极射线发光与高空间和时间分辨率。探索成分均匀性，相分离和压电场的影响也包括在研究中。的微观结构特性与光电性能，以了解生长参数对整体器件性能的作用。

Non-technical Description: This collaborative research project studies an underexplored semiconductor materials system that involves boron incorporation in the four-element alloys of BAlGaN. These materials are a new generation of III-V alloy system compared to the AlInGaN alloys that have been developed to provide high-efficiency lighting. The solid-state illumination and lighting technology, based upon AlInGaN alloys, has found wide practical applications in automotive, liquid-crystal-display back panel, mobile communications and signage illumination, and will soon dominate in general lighting. However, there are still important limitations for AlInGaN alloy materials. This research project explores the advantages of incorporation of boron into these alloys with the ultimate goal to achieve better strain matching in heterostructures, higher efficiency and potentially p-type doping in the new alloy system. The research is integrated with the educational activities including research training for graduate and undergraduate students in the growth, characterization, and processing of these novel materials, and various outreach programs at both Georgia Institute of Technology and Arizona State University.Technical Description: The primary focus of this research project is to study the physical, chemical, and electronic properties of high-quality thin films of boron-containing III-nitride semiconductor ternary and quaternary alloys in the technologically important range of compositions and to develop an in-depth understanding of fundamental materials science for improved optoelectronic device designs. The research team uses advanced metalorganic chemical vapor deposition (MOCVD) epitaxial film growth systems, and performs in-depth studies of the effects of growth conditions, substrate materials, substrate orientation, and doping. The materials properties are studied in detail using state-of-the-art nanoscale characterization tools: the crystal structure is studied using atomic-resolution aberration-corrected transmission electron microscopy; the electronic band structure is determined by electron holography; and the optical properties are measured by cathodoluminescence with high spatial- and temporal-resolution. Exploring the effects of compositional homogeneity, phase separation, and piezoelectric fields is also included in the research. The microstructural properties are correlated with the optoelectronic properties to understand the role of growth parameters on overall device performance.