SBIR Phase I: Gallium Nitride Photodiode Array for Deep Ultraviolet (DUV) Lithography Dose and Beam Uniformity Measurements

这项第一阶段SBIR建议致力于开发一种标准质量的固态探测器技术，用于测量深紫外线(DUV)辐照度。DUV光刻设备制造商特别需要一种准确而稳定的探测器技术来测量准分子激光(248、193、157 nm)脉冲能量和晶片平面剂量均匀度的总紫外线(UV)曝光量。目前的行业标准是KrF 248 nm准分子激光器。利用193 nm ARF激光的系统现已准备就绪，157 nm F2激光系统将很快成为行业标准。对DUV检测产品的要求是：在强烈紫外线照射下的高耐用性、大面积响应的一致性、低噪声、线性响应和高功率饱和点。现有的紫外光检测技术，即硅或GaAsP的紫外光降解，限制了这些材料在新一代DUV光刻工具(F2准分子激光器)中的应用。一种可用于所有UV波长的单一检测/功率测量技术将最大限度地减少每一代新一代光刻系统所需的新工程工作。宽带隙半导体氮化镓(GaN)被认为是满足当前和未来DUV光刻需求的理想材料体系。由GaN及其铝(AlGaN)三元化合物制成的P-I-N和肖特基势垒光电二极管探测器，对365 nm以下的波长具有高的量子效率响应。它们具有低噪声、几十年的入射功率线性响应和高带宽。最重要的是，对于DUV辐照度测量，该材料系统具有在长时间暴露于高强度UV辐射下抵抗降解的潜力。在这项提案中，提出了评估GaN和AlGaN紫外探测器在强烈、长时间的DUV照射下的稳定性和长期稳定性的计划，并开发了该行业最重要的、目前无法获得的检测产品之一，即用于在晶片平面上测量功率和剂量均匀度的大面积、多元素光电二极管阵列。除了DUV光刻，第三类氮化物技术还有许多其他工业和科学应用，包括UV固化和干燥、印刷电路板制造、杀菌控制、光疗、燃烧监测和太阳辐射测量。

This Phase I SBIR proposal addresses the development of a standards quality, solid state detector technology for measurement of deep ultraviolet (DUV) irradiance. There is a particular need among manufacturers of DUV photolithography equipment for an accurate and stable detector technology to measure excimer laser (248, 193, 157nm) pulse energy and total ultraviolet (UV) exposure for wafer plane dose uniformity. The current industry standard is the KrF 248 nm excimer laser. Systems utilizing the 193 nm ArF laser are ready now and 157 nm F2 laser systems will soon become the industry standard. The requirements for DUV detection products are high durability under intense UV exposure, uniformity of response over large areas, low noise, linear response, and a high power saturation point. The ultraviolet degradation of existing UV detection technologies, i.e. silicon or GaAsP, restricts the utilization of these materials for the new generation (F2 excimer laser) of DUV lithography tools. A single detection/power measurement technology that can be used for all UV wavelengths would minimize the new engineering work necessary for each new generation of photolithography systems. The wide band gap semiconductor gallium nitride (GaN) is proposed as the ideal material system to meet the current and future needs for DUV photolithography. P-I-N and Schottky barrier photodiode detectors made from GaN, and its ternary compounds with aluminum (AlGaN), have high quantum efficiency responsivity for wavelengths shorter than 365 nm. They have low noise, linear response over several decades of incident power, and high bandwidth. Most importantly for DUV irradiance measurements, the material system has the potential to resist degradation under prolonged exposure to high intensity UV radiation. In this proposal, plans are presented to evaluate the robustness and long term stability of GaN and AlGaN UV detectors under intense, prolonged DUV exposure, and also to develop one of the most important, and currently unavailable, detection products for this industry, a large area, multi-element photodiode array for power and dose uniformity measurements at the wafer plane. In addition to DUV lithography, there are many other industrial and scientific applications for group III-nitride technology including UV curing and drying, printed circuit board fabrication, sterilization control, phototherapy, combustion monitoring, and solar irradiance measurement.