GaN-Based Vertical Cavity Surface Emitting Lasers and Resonant Cavity Light Emitting Diodes

ECCS-0725506 Morkoc，HadisVirginia Commonwealth UniversityIntellectual Merits更明亮和更高效的光源可能基于垂直腔技术，对于完全成功的固态照明和电信来说是必不可少的。拟议的研究采用新的外延膜生长/制造技术的高量子效率GaN基微腔发光二极管和电注入垂直腔面发射激光器在紫绿色光谱区。短波长GaN基垂直腔激光器将很可能为高密度光数据存储和高速光通信以及照明提供基础。非相干微腔发射器由于其方向性、光谱纯度和增加的光子提取效率而超过其常规对应物，使其成为具有高显色指数和显示器的固态照明的理想选择。原位和非原位外延横向过生长技术都将用于降低GaN材料中的缺陷密度。垂直腔结构将被制作在横向过度生长的GaN的几乎无缺陷的翼区上，以避免由扩展和点缺陷引起的非辐射中心。独特的外延横向过生长技术将允许底部金属和/或电介质反射器叠层也用作生长掩模。通过引入第二个横向过生长步骤，电流传导将只允许通过器件的无缺陷有源区，促进有效的空穴注入。更广泛的影响拟议的研究可能会产生高亮度的光源，一般照明与节能和减少碳足迹，显示器，和垂直激光器的光存储/网络。因为，对光存储的需求正在增长，密集集成的蓝色垂直腔激光器的发展可以满足更快的读出和写入的需求。考虑到所提出的设备结构的新奇，预计将进行激烈的工业合作。该提案将为学生和实习生提供跨学科学习的机会，与集团和其他地方的国际科学家进行互动，发展工业网络，以及实现新技术对市场和环境的影响。

ECCS- 0725506Morkoc, HadisVirginia Commonwealth UniversityIntellectual MeritsBrighter and higher efficiency light sources possibly based on vertical cavity technology are imperative for fully successful solid-state lighting and telecommunications. The proposed research employs novel epitaxial film growth/fabrication techniques for high quantum efficiency GaN-based microcavity light emitting diodes and electrically injected vertical cavity surface emitting lasers in the violet-green spectral region. Short wavelength GaN-based vertical cavity lasers will very likely provide the foundation for high-density optical data storage and high-speed optical communication, and lighting. The incoherent microcavity emitters also surpass their conventional counterparts due to their directionality, spectral purity, and increased photon extraction efficiency, making them ideal for solid-state lighting with high color rendering index and displays. Both in situ and ex situ epitaxial lateral overgrowth techniques will be used to reduce defect densities in the GaN material. Vertical cavity structures will be fabricated on the nearly defect-free wing regions of the laterally overgrown GaN to avoid nonradiative centers caused by extended and point defects. A unique epitaxial lateral overgrowth technique will allow the bottom metal and/or dielectric reflector stacks, to be used also as the growth masks. By introducing a second lateral overgrowth step, the current conduction will be allowed only through the defect-free active region of the device, promoting efficient hole injection.Broader ImpactsThe proposed research can potentially produce high brightness light sources for general lighting with energy savings and reduced carbon footprint, displays, and vertical lasers for optical storage/networks. Because, the demand for optical storage is growing, development of densely integrated blue vertical cavity lasers can meet the need for faster read-out and writing. Considering the novelty of the proposed device structures intense industrial collaborations are anticipated. This proposal will provide the students and interns with opportunities for cross-disciplinary learning, interactions with international scientists in the group and elsewhere, development of industrial networking, and for realization of the impact of new technologies on the marketplace and environment.