Impact of Growth and Process Parameters in Growth of Strain Reduced III-Nitride Layers on Ion Implanted AlN/Si Substrates

技术：本项目致力于发展对硅上过度生长的氮化镓(GaN)层应变降低机制的基本了解。其核心思想是通过AlN缓冲层使用离子注入在硅衬底中的AlN缓冲层和硅衬底之间的界面附近产生高度缺陷层。由于缺陷层的形成而产生的应变的减少有望大大减少GaN薄膜的断裂以及穿线位错缺陷的形成。初步结果表明，使用这种方法可以大幅降低GaN中的应变。然而，对这种改进负责的基本机制尚不清楚。在这个项目中，将使用各种非原位和原位材料表征技术来阐明离子注入条件与外延生长的AlN缓冲层的形态和厚度以及在外延生长的GaN层中观察到的位错和薄膜断裂的类型和密度之间的关系。非技术性：本项目解决了材料科学中具有高度技术相关性的热门领域的基础研究问题。该项目的成功将有助于在Si(111)和Si(100)衬底上大面积位错还原Ⅲ-氮化物上开发高性能的光电子器件。该项目培养研究生的领导力，同时为本科生提供机会，通过在合作环境中从研究生和教职员工那里获得指导，学习科学研究和解决问题的技能。该项目涉及奥尔巴尼州立大学纳米科学与工程学院和宾夕法尼亚州立大学材料科学与工程系的教职员工和学生。此外，预计每年将有1000多个家庭和他们的孩子在一个有趣和非正式的环境中接触到科学技术，这是一个公共外展项目-购物中心的科学和技术展览。

Technical: This project focuses on the development of a fundamental understanding of strain reduction mechanisms in overgrown gallium nitride (GaN) layers on silicon. The central idea is to use ion implantation through an AlN buffer layer to create a highly defective layer in silicon substrate, in the vicinity of the interface between the AlN buffer and silicon substrate. Reduction in strain due to the formation of the defected layer is expected to greatly reduce GaN film fracturing as well as the formation of threading dislocation defects. Preliminary results suggest that a large reduction in strain in GaN is possible using this approach. However, the fundamental mechanism responsible for such improvements is not yet understood. In this project, various ex-situ and in-situ materials characterization techniques will be used for the formulation of an understanding of the relationship between ion implantation conditions and the morphology and thickness of the epitaxially grown AlN buffer layer as well as the type and density of dislocations and film fracturing observed in the overgrown GaN layer.Non-technical: This project addresses basic research issues in a topical area of materials science with high technological relevance. The success of the project would help to the development of high performance optoelectronic devices on large area dislocation reduced III-nitrides on Si(111) and Si(100) substrates. The project cultivate a sense of leadership in graduate students while offering undergraduate students an opportunity to learn scientific research and problem-solving skills via mentoring from graduate students and faculty in a collaborative environment. The project involves faculty and students at the College of Nanoscale Science and Engineering of the University at Albany - State University of New York and at the Department of Materials Science and Engineering at Pennsylvania State University. In addition, a public outreach program, Science and Technology exhibit in the Mall, is expected to expose over 1000 families and their children to science and technology each year in a fun and informal environment.