CAREER: Micromachining of Gallium Nitride and Related Materials for Microwave and Optoelectronic Applications

职业：用于微波和光电应用的氮化镓及相关材料的微加工

• 批准号: 9875600
• 负责人: Patrick Fay
• 金额: $ 20万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2004-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9875600&HistoricalAwards=false
• 关键词: CAREER; Micromachining; Gallium; Nitride; Related

9875600FayAn integrated plan for career development based on research on micromachining of GaN and related materials (e.g. A1GaN, InGaN, InA1N) is proposed. Three micromachined devices for microwave and optoelectronic applications that can only be realized using micromachining approaches are proposed to demonstrate the technology: an inline transmissive microwave power sensor, a piezoelectrically assisted microwave micromechanical switch, and an arbitrary curvilin-ear mirror surface for the realization of surface emitting blue heterostructure diodes. The re-search work proposed includes development of the necessary micromachining fabrication pro-cesses, including the development and implementation of a computerized submersible angle-controlled stage for generating arbitrarily-shaped etch sidewalls using photoelectrochemical wet etching. In addition, a full characterization of the etch reaction kinetics will be performed, and a process model developed for inclusion into the control software for the angle-controlled stage in order to etch curved as well as arbitrarily angled surfaces. The thermal conductivity and thermo-electric properties of GaN and A1GaN as a function of A1 mole fraction will also be investigated experimentally both in order to optimize the material selection for the inline transmissive power sensor, as well as to provide additional experimental insight into the electronic band structure of this nascent material system. The development and demonstration of a viable micromachining technology in this material system will have wide-ranging impact on the fields of high-power and high-temperature microwave electronics as well as short-wavelength optoelectronics. The inline transmissive power sensor is designed to be integrable with high-power GaN-based HEMTs, providing for the ability to directly measure amplifier output power over very wide bandwidths without the need for large coupling structures. The piezoelectrically-assisted micro-wave micromechanical switch is expected to provide the same benefits as micro-electro-me-chanical switches in Si and other III-V materials, but with the added benefit of lower activation voltage due to the piezoelectric properties of GaN and integrability with high-speed, high-power GaN HEMTs. Finally, the arbitrary curvilinear mirror surface technology will allow the imple-mentation of surface-emitting heterostructure diodes to greatly ease the difficulty in packaging these devices for high-density optical storage and display applications. In addition to providing a more easily packaged surface-emitting structure rather than an edge-emitting diode structure, the ability to tailor the curvature of the mirror surface through the use of the angle-controlled etching stage also permits the control of the stigmation of the far-field intensity pattern of the emitter, eliminating the need for bulky and difficult-to-align external optical components to circularize the light beam.The educational programs that are included within the scope of activities of this research project include numerous opportunities for undergraduate students to participate directly in research activities. These opportunities include participation in the development of micromachining fabrication processes, device fabrication and verification, and microwave and optoelectronic testing of the finished devices. The research results originating from this work will also be incorporated into undergraduate course work; the Integrated Optoelectronics, Wire-less Communications and Microwave Measurements, and Electronic Circuits courses taught by Prof. Fay will all benefit directly through inclusion of results from this work. Students will also be given the opportunity to be involved in this project through the senior design capstone course in the department; the numerous opportunities for fabrication process design as well as imple-mentation of the computerized angle-controlled etching stage are well-suited for year-long undergraduate design projects. An additional program to be supported by this program is the expansion of Prof. Fay's Electronics Hobby Evenings program to include more students from other departments and colleges across the university as well as to include interested high school students and community members.***

9875600 Fay提出了基于GaN及其相关材料（如A1 GaN、InGaN、InA 1 N）微加工研究的职业发展综合计划。三个微加工设备的微波和光电应用，只能实现使用微加工方法，提出了演示技术：一个内联透射微波功率传感器，压电辅助微波微机械开关，和任意curvilin-ear镜面实现表面发射蓝色异质结二极管。建议的研究工作包括开发必要的微加工制造工艺，包括开发和实施一个计算机化的潜水角度控制阶段，用于使用光电化学湿法蚀刻产生任意形状的蚀刻侧壁。此外，将进行蚀刻反应动力学的完整表征，并开发工艺模型以纳入角度控制阶段的控制软件中，以便蚀刻弯曲和任意角度的表面。GaN和A1 GaN的热导率和热电性能作为A1摩尔分数的函数也将进行实验研究，以优化内联透射式功率传感器的材料选择，以及提供额外的实验洞察这个新生材料系统的电子能带结构。在这种材料系统中开发和展示可行的微机械加工技术将对高功率和高温微波电子学以及短波长光电子学领域产生广泛的影响。内联透射式功率传感器被设计为可与高功率GaN基HEMT集成，从而提供在非常宽的带宽上直接测量放大器输出功率的能力，而不需要大的耦合结构。压电辅助的微波微机械开关有望提供与Si和其他III-V族材料中的微机电开关相同的益处，但由于GaN的压电性质以及与高速、高功率GaN HEMT的可集成性而具有较低激活电压的附加益处。最后，任意曲面镜面技术将使表面发射异质结二极管的实现大大减轻了高密度光存储和显示应用中封装这些器件的困难。除了提供比边缘发射二极管结构更容易封装的表面发射结构之外，通过使用角度受控的蚀刻阶段来调整镜面的曲率的能力还允许控制发射器的远场强度图案的像散，消除了对笨重且难以-对准外部光学元件，使光束呈圆形。本研究项目活动范围内的教育项目包括为本科生提供许多直接参与研究活动机会。这些机会包括参与微加工制造工艺的开发，器件制造和验证，以及成品器件的微波和光电测试。源于这项工作的研究成果也将被纳入本科课程工作;集成光电子学，无线通信和微波测量，以及Fay教授教授的电子电路课程都将直接受益于这项工作的结果。学生还将有机会通过该部门的高级设计顶点课程参与该项目;制造工艺设计以及计算机化角度控制蚀刻阶段的实施的众多机会非常适合长达一年的本科设计项目。该计划支持的另一个计划是扩大Fay教授的电子爱好晚会计划，以包括来自大学其他部门和学院的更多学生，以及包括感兴趣的高中学生和社区成员。