SBIR Phase II: Microdisplays Based on III-Nitride Wide Band Gap Semiconductors

该SBIR第二阶段项目的目标是将已演示的氮化镓(GaN)微显示技术推向工业成熟和最终商业化水平。该项目的目标将在第一阶段取得的示范成果的基础上，通过进一步优化微显示器件的结构设计和制造工艺来实现。基于高效半导体微发光二极管(MicroLED)阵列技术的GaN微显示器是首个基于半导体LED的微显示器。具体地说，通过倒装芯片键合将GaN微LED阵列与Si CMOS驱动电路混合集成，有源矩阵可寻址GaN微显示器将具有紧凑的尺寸，并将能够支持更多的信息内容和电影显示，因为它们具有高的像素填充因子、均匀性、亮度和功率效率。GaN微LED独特的固有特性--高亮度(直径18微米的微LED输出功率为10微瓦)、宽视角(~160度)、快速响应时间(1 Ns)以及高耐热和抗振动性能，使GaN微显示器成为现代车辆和飞机上的平视显示器(HUD)、消防员和其他救援人员的头盔显示器(HMD)以及野外应用的手持微型投影仪等对环境要求苛刻的应用的完美解决方案。微显示器尺寸小(通常不到1英寸)，分辨率从低端到XVGA格式以上。它们被光学放大以形成放大的虚拟或投影图像以供用户观看。微型显示器可用于各种设备，如头戴式显示器、视频耳机、便携式取景器、投影电视、平视显示器等，并具有许多商业应用。与其他微显示技术相比，GaN微显示器具有优越的性能，特别适合于要求高亮度、高可靠性和宽工作温度范围的环境要求高的应用。本文研制的GaN微发光二极管阵列只需对材料成分稍作改动，就可以实现发射波长从绿光到紫外光的变化，非常适合用于新型化学生物试剂探测器阵列或DNA/蛋白质微芯片的荧光分析。GaN微LED阵列还具有光学链路和并行计算等应用的潜力。其他应用还包括生物、医疗和保健系统的空间分辨光学研究。这项研究还将丰富宽禁带半导体微纳光子学的一般知识。

The goal of this SBIR Phase II project is to bring the demonstrated Gallium Nitride (GaN) microdisplay technology to industrial maturity and to final commercialization levels. The project's goal will be accomplished by further optimizing the microdisplay device structural design and fabrication process based on the demonstrative results obtained in Phase I. Based on high-efficiency semiconductor micro-light-emitting diode (microLED) array technology, the GaN microdisplay is the first of its kind based on semiconductor LEDs. Specifically, by the hybrid integration of GaN microLED arrays with Si CMOS driver circuits through flip-chip bonding, active matrix addressable GaN microdisplays will have a compact size and will be able to support more information content and movie display due to their high pixel filling factor, uniformity, luminance, and power efficiency. The unique intrinsic properties of GaN microLEDs - high brightness ( 10 microwatt optical output power for microLEDs of 18 micrometer in diameter), wide viewing angle (~ 160 degrees), fast response time ( 1 ns), and high thermal and vibrational resistance, make GaN microdisplays a perfect solution for environmentally demanding applications such as head-up displays (HUD) in modern vehicles and aircrafts, head-mounted displays (HMD) for firefighters and other rescue operatives, and hand-held mini-projectors for field applications.Microdisplays have a small size (typically less than 1 inch diagonal) with a resolution from low end to above XVGA format. They are magnified by optics to form enlarged virtual or projected images for viewing by a user. Microdisplays can be used in a variety of devices such as head-mounted displays, video headsets, camcorder viewfinders, projection TV, head-up displays, etc. and have many commercial applications. GaN microdisplay, with its superior performance over other microdisplay technologies, is especially suitable for environmentally demanding applications that require high brightness, high reliability, and wide operating temperature range. With a slight modification of the material composition, GaN microLED arrays developed here can vary the emitted wavelength from the green to the ultraviolet range, which is very suitable for fluorescence analysis used in new type chemical-biology agent detector array or DNA/protein microchips. The GaN microLED array also has the potential for applications such as optical links and parallel computing. Other applications also include spatially resolved optical studies of biological, medical, and health care systems. The research will also enrich the general knowledge of wide bandgap semiconductor micro- and nano-photonics.