SBIR Phase II: A Novel Microwave Technique for Rapid Thermal Processing of Silicon Carbide Wide Bandgap Semiconductor

这个小型企业创新研究（SBIR）第二阶段项目将开发一种独特的固态微波技术，能够达到超高温（高达2150摄氏度）和超快的热处理大宽带隙半导体晶片。广泛地认识到，现有的注入后退火工艺是限制宽带隙半导体器件的性能和可靠性的瓶颈。该技术降低了注入半导体的薄层电阻和表面粗糙度，使得能够以较低的成本制造更高性能、更高功率效率的器件。作为第一阶段研究的一部分，微波退火样品在p型和n型注入SiC中均显示出创纪录的低薄层电阻和表面粗糙度。第二阶段的研究是将基于微波的快速热处理（RTP）扩展到其他宽带隙材料，如GaN，并允许更大尺寸的晶片的RTP。原型系统将从单加热头系统升级为具有多个加热头和多个传感器的阵列的系统。将开发以计算机为基础的自动控制，以调节晶圆温度的均匀性和稳定性。该研究预计将显示基于微波的RTP在商业上用于大型SiC晶片的可行性。该技术改进了注入后退火工艺，以最大限度地减少SiC和GaN的薄层电阻和表面粗糙度，从而降低了器件功耗并降低了热预算。较低的表面粗糙度提高了SiC亚微米器件的可靠性，从而提高了成品率并降低了制造成本。在商业上，这是一项使能技术，将在功率器件、发光二极管（LED）、高温和高频电子器件等领域制造更好、更低成本的化合物半导体器件。这项技术的社会和商业影响可能是巨大的。例如，LED技术可以将美国照明所需的能源比例从22%降低到7%，每年节省170亿美元，减少1.55亿吨二氧化碳排放。LED设备制造商正在寻找诸如RTP之类的使能器技术来实现这一目标。Cree、GE Research和ARL认识到这项研究的技术和商业意义，正在通过提供技术专长、测试晶片、获得设备和其他实物服务来支持这项研究工作。此外，这项技术可以扩展到其他应用，例如用于纳米CMOS器件的超浅结RTP、晶片键合、MEMS以及SiC纳米材料的加工。

This Small Business Innovation Research (SBIR) Phase II project will develop a unique solid-state microwave technique capable of reaching ultra-high temperature (up to2150 deg C) and ultra-fast thermal processing of large wide band gap semiconductor wafers. It is widely recognized that the existing post-implant anneal process is a bottleneck limiting the performance and reliability of wide band gap semiconductor devices. This technique lowers the sheet resistance and surface roughness of the implanted semiconductor, enabling the fabrication of higher performance, more power efficient devices at lower cost. As part of the Phase I research, the microwave annealed samples showed a record low sheet resistance and surface roughness in both p-type and n-type implanted SiC. The Phase II research is to extend microwave-based rapid thermal processing (RTP) to other wide band gap materials such as GaN and to allow for RTP of larger sized wafers. The prototype system will be upgraded from a single-heating-head system to a system with an array of multiple heads and multiple sensors. Computer-based automated control will be developed to regulate wafer temperatures uniformity and stability. The research is anticipated to show feasibility of microwave-based RTP in commercial use for large SiC wafers. The technology improves post-implant anneal process to minimize sheet resistance and surface roughness of SiC and GaN, which consequently reduces the device power consumption and lowers the thermal budget. Lower surface roughness improves SiC sub-micron device reliability, consequently improving yield and reducing manufacturing cost.Commercially, this is an enabler technology that will make better and lower-cost compound semiconductor devices in areas such as power devices, light emitting diodes (LEDs), high temperature and high frequency electronics. The societal and commercial impact of the technology can be enormous. LED technology, for example, can potentially reduce the percentage of energy required for lighting in the U.S. from 22% to 7%, saving $17 billion per year and reduce CO2 emissions by 155 million tons. Manufacturers of LED devices are looking for enabler technologies such as RTP to reach this goal. Recognizing the technological and the commercial significance of the research, Cree, GE Research and ARL are supporting the research effort by providing the technological expertise, test wafers, access to equipment, and other in-kind services.Furthermore, the technology can be extended to other applications such as RTP of ultra-shallow junction for nano-scale CMOS devices, wafer bonding, MEMS as well asprocessing of SiC nano-materials.