Global Strain-Free III-Nitride Heterostructures: Growth, Structure and Near-Infrared Optical Properties

摘要技术描述：本项目的主要目的是建立晶格匹配和应变平衡的AlInN/(In)GaN多量子阱结构的生长、原子结构和光学性质之间的关系。为了将生长模式与微观结构和近红外光学性能联系起来，利用等离子体辅助分子束外延（MBE）在极高质量的准块状GaN衬底上生长出AlInN/(In)GaN异质结构，利用高分辨率x射线衍射和透射电子显微镜对半导体材料的原子结构进行了详细表征。利用傅里叶变换红外光谱对材料的近红外光学特性进行了实验研究。该项目促进了对复杂红外光电器件中无应变iii -氮化物材料MBE生长的理解。详细研究和比较了极性和非极性氮化镓衬底上材料生长的基本机制，如附原子动力学和杂质掺入。目标是充分了解和控制生长过程，由此产生的微观结构和红外光学特性，以实现该材料体系的理论潜力。确定了复杂氮化物异质结构的MBE生长，特别是金属调制外延的基本和实际限制。非技术描述：该项目研究了一类用于红外光源和探测器的新型半导体材料，这些材料有可能实现新的实际应用（红外光谱、红外成像和电信），对社会有广泛的好处。这项研究还通过将跨学科研究与更广泛的物理和工程教育和培训相结合，增加了所有年龄段学生在传统课堂内外的学习机会。特别是，参与该项目的学生有机会获得最新材料制造和表征工具和技术的实践经验。通过与学术界、工业界和国家实验室的几个研究小组合作，将科学发现的兴奋传递给学生。与工业界和联邦资助实验室的科学家的互动为学生提供了对科学追求的不同看法，以及对他们的职业选择的更好理解。pi和学生还将参加在校内或当地学校组织的推广活动，通过普渡大学，增加K-12学生和公众对物理学、材料科学和工程学之间的现代科学主题的接触。这是一个非常受欢迎的“路上的物理”项目。

AbstractTechnical description: The main objective of this project is to establish the relationship between growth, atomic structure and optical properties of lattice-matched and strain-balanced AlInN/(In)GaN multi-quantum well structures. In order to correlate the growth modes with microstructure and near-infrared optical properties, AlInN/(In)GaN heterostructures are grown by plasma-assisted Molecular Beam Epitaxy (MBE) on extremely high quality quasi-bulk GaN substrates, the atomic structure of the semiconductor materials is characterized in detail using high-resolution x-ray diffraction and transmission electron microscopy, while the near-infrared optical properties of the materials are examined experimentally using Fourier transform infrared spectroscopy. This project advances the understanding of MBE growth of strain-free III-nitride materials for complex infrared optoelectronic devices. Basic mechanisms of material growth such as adatom kinetics and impurity incorporation on polar and non-polar GaN substrates are studied in detail and compared. The goal is to achieve adequate understanding and control of the growth process, resulting microstructure and infrared optical properties in order to realize the theoretical potential of this material system. The fundamental and practical limitations for MBE growth, in particular for metal-modulated epitaxy, of complex nitride heterostructures are established. Non-technical description: This project investigates a new class of semiconductor materials for infrared light sources and detectors that has the potential to enable new practical applications (infrared spectroscopy, infrared imaging, and telecommunications) with broad benefits to society. This research also increases the learning opportunities for students of all ages, inside and outside the traditional classroom by integrating interdisciplinary research with broader physics and engineering education and training. In particular, the students involved in this project have the opportunity to acquire hands-on experience with the latest materials fabrication and characterization tools and techniques. The excitement of scientific discovery is conveyed to students through collaborations with several research groups in academia, industry, and national laboratories. The interaction with scientists in industry and a federally funded laboratory offers the students a different view of the scientific pursuit, as well as a better understanding of their career options. The PIs and students also will participate in outreach activities organized either in-house or at local schools to increase exposure of K-12 students and the general public to modern scientific topics at the border between physics, material science, and engineering through Purdue?s highly popular Physics on the Road Project.