Vertical Cavity Blue and Ultraviolet Light Emitters

垂直腔蓝光和紫外光发射器

• 批准号: 0070887
• 负责人: Arto Nurmikko
• 金额: $ 24万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2004-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0070887&HistoricalAwards=false
• 关键词: Vertical; Cavity; Blue; Ultraviolet; Light

0070887NurmikkoIn this project, Nurmikko, his graduate students, and collaborators aim to study, design, and develop optoelectronic device and optical physics concepts that will lead to the realization of blue and ultraviolet vertical cavity light emitters, based on wide band gap nitride semiconductor heterostructures. In particular, the specific goals of the three year program are the demonstration and fabrication of (a) a resonant cavity light emitting diode (RCLED), and (b) a vertical cavity surface emitting laser (VCSEL). Although closely interconnected, the technical challenges facing the development of these new, compact short wavelength devices can be logistically grouped into into two broad areas: (i) the approach and implementation of the optical microresonator structure and (ii) the design and realization of a pn-junction based injector structure. To achieve high Q-factor vertical cavities for InGaN and AlGaN heterostructures, Nurmikko and co-workers aim is to create processing techniques that will create optical structures reaching Q-factors in the 1000-2000 range for reducing the laser threshold requirements. The approach is based on monolithic integration of two dielectric DBRs and also focus on "hybrid" structures with one dielectric and one as-grown DBR. Study of the optical gain spectra of the VCSEL structures forms another key project area, to detail the gain spectra of the InGaN and AlGaN active media for optimizing these for low threshold VCSELS. Nurmikko and co-workers will study fundamental microcavity physics to enhance light emission from InGaN and AlGaN VCSELs and RCLEDS. Excitonic enhancement to oscillator strength can concentrate optical gain so as to significantly reduce a nitride VCSEL threshold. Similarly, spontaneous emission properties for an RCLED are expected to be dramatically enhanced.For achieving a diode vertical cavity emitter, Nurmikko and co-workers will study lateral p-injection in two types of experiments: (i) the use of near field imaging techniques to study lateral diffusion, and (ii) the design of LED microstructures where current spreading can be obtained from electroluminescence spatial imaging. For the blue and NUV VCSEL work they will also concentrate on the incorporation of p-GaN/AlGaN modulation doped heterostructures for enhancing the p-side conductivity. One of the specific features that they will address concerns the tailoring of the electronic structure so that interface scattering can be reduced (hence the hole mobility enhanced). They propose to use the very large built-in piezoelectric and spontaneous dielectric polarization effects to electrostatically design the heterojunction confinement profile. They will also study the use of epitaxial lateral overgrowth (ELOG) to facilitate both the incorporation of "buried" DBR mirrors as well as to define current apertures for channeling hole transport to the active device region (as defined by the vertical resonator).A specific characteristic of the ongoing research is a close collaboration with Hewlett-Packard (both HP Labs and the Optoelectronic Division, now renamed Agilent Technologies), as well as Sandia National Laboratories. This industry/government laboratory connection will be an integral part of the project work.***

0070887Nurmikko 在这个项目中，Nurmikko、他的研究生和合作者旨在研究、设计和开发光电器件和光学物理概念，从而实现基于宽带隙氮化物半导体异质结构的蓝色和紫外垂直腔光发射器。 特别是，这个为期三年的计划的具体目标是演示和制造（a）谐振腔发光二极管（RCLED）和（b）垂直腔表面发射激光器（VCSEL）。 尽管紧密相连，但开发这些新型紧凑型短波长器件所面临的技术挑战可分为两大领域：(i) 光学微谐振器结构的方法和实现，以及 (ii) 基于 pn 结的注入器结构的设计和实现。 为了实现 InGaN 和 AlGaN 异质结构的高 Q 因子垂直腔，Nurmikko 及其同事的目标是创建加工技术，创建 Q 因子达到 1000-2000 范围内的光学结构，从而降低激光阈值要求。 该方法基于两个电介质 DBR 的单片集成，并且还重点关注具有一种电介质和一个原生 DBR 的“混合”结构。 VCSEL 结构的光学增益光谱研究构成了另一个关键项目领域，详细介绍了 InGaN 和 AlGaN 活性介质的增益光谱，以优化低阈值 VCSELS。 Nurmikko 和同事将研究基础微腔物理学，以增强 InGaN 和 AlGaN VCSEL 和 RCLED 的发光能力。 激子增强振荡器强度可以集中光学增益，从而显着降低氮化物VCSEL阈值。 同样，RCLED 的自发发射特性预计将显着增强。为了实现二极管垂直腔发射器，Nurmikko 和同事将在两种类型的实验中研究横向 p 注入：(i) 使用近场成像技术来研究横向扩散，以及 (ii) LED 微结构的设计，其中电流扩散可以从电致发光空间获得 成像。 对于蓝色和 NUV VCSEL 工作，他们还将集中精力结合 p-GaN/AlGaN 调制掺杂异质结构以增强 p 侧电导率。 他们将解决的具体特征之一涉及电子结构的定制，以便减少界面散射（从而增强空穴迁移率）。 他们建议使用非常大的内置压电和自发介电极化效应来静电设计异质结限制轮廓。 他们还将研究使用外延横向过度生长 (ELOG) 来促进“埋入式”DBR 反射镜的结合，以及定义用于将空穴传输引导到有源器件区域（由垂直谐振器定义）的电流孔径。正在进行的研究的一个具体特点是与惠普（惠普实验室和光电部门，现更名为安捷伦）的密切合作。 技术）以及桑迪亚国家实验室。 这种行业/政府实验室连接将成为项目工作的一个组成部分。***