Short Wavelength UV LEDs Based on Bulk Nitride Substrates

描述(申请人提供)：现代生物医学仪器依靠紫外线(UV)光源来实施广泛的检测技术。这项拟议工作的长期目标是开发固态紫外光发光二极管(UV LED)，作为现有波长小于360 nm的灯源的替代品，在这种情况下，商业固态设备不存在。提出的方法是基于最近开发的块体单晶氮化铝(AIM)衬底上在AlGaN(AlGaN)材料系统中制备UV LED的基础上。这种AIM基板的独特性能，包括它与AlGaN合金的紧密晶格匹配和极低的缺陷密度，使其能够制造出比其他基板材料更短、更高效率、更高亮度和更长寿命的LED。第一阶段的计划是设计和演示发射波长为340 nm的紫外光LED。将在AIGaN系统中设计、建模、生长和表征一种新的外延结构。然后，器件将被制造和测试。在波长为340 nm或更短的情况下，这种UV LED将提供比现有灯具更高的效率、紧凑性、可靠性和成本，增强生物医学研究工具的性能和实用性，并可能促进新一代紧凑型微流体仪器的发展。最终，这将使人们能够更好地了解构成人类健康基础的生物机制，发现新的治疗方法和诊断方法，并更精确地控制药品制造过程和药品质量。

DESCRIPTION (provided by applicant): Modern biomedical instrumentation relies on ultraviolet (UV) light sources to implement a broad range of detection techniques. The long-term goal of the proposed effort is the development of solid-state UV light emitting diodes (UV LEDs) as a replacement for existing lamp sources at wavelengths shorter than 360 nm, where commercial solid-state devices do not exist. The proposed approach is based on the fabrication of UV LEDs in the aluminum gallium nitride (AIGaN) material system on a recently-developed bulk single-crystal aluminum nitride (AIM) substrate. The unique properties of this AIM substrate, including its close lattice- match to AIGaN alloys and its exceedingly low defect density, enable the manufacture of LEDs with shorter wavelength, higher efficiency, higher brightness, and longer lifetime than those fabricated on alternative substrate materials. The Phase I program is to design and demonstrate a UV LED with emission at 340 nm. A novel epitaxial structure in the AIGaN system will be designed, modeled, grown and characterized. Then devices will be fabricated and tested. At the 340 nm wavelength and shorter, such UV LEDs will offer improved efficiency, compactness, reliability, and cost relative to existing lamps, enhancing the performance and utility of biomedical research tools and perhaps fostering a new generation of compact microfluidic instruments. Ultimately, this will enable a greater understanding of the biological mechanisms that underlie human health, the discovery of new therapies and diagnostics, and more precise control of pharmaceutical manufacturing processes and drug quality.