STTR Phase I: Growth of 3C-SiC Substrates using High-Temperature Chemical Vapor Deposition

这个小型企业技术转移（STTR）第一期项目旨在开发新的材料生长技术，用于制造高功率、高频、高温和高辐射硬度军事、太空和商业应用的立方3C-SiC多型半导体衬底。SiC外延生长的新工艺利用了气相和表面反应的新机制。这些机制是通过使用卤碳生长化学取代传统的基于丙烷的体系来提供的。应用于4H-SiC多型的同外延生长，新生长方法在低至1350℃的温度下获得了无缺陷的脱毛层，这远远低于高质量生长的可能温度。与此同时，在常规的4HsiC生长温度下，与基于丙烷的生长相比，生长速率急剧增加。halo-碳生长有望解决阻碍3C-SiC商业化的关键问题，如不利的均相反应导致的形态退化、晶格失配相关缺陷的产生以及硅蒸气冷凝导致的生长速率降低。目前还没有3C-SiC多型晶圆的商业供应。加大开发和商业化的努力。-日本和欧洲的碳化硅技术可能会使美国的宽带隙产业在碳化硅电子产品的成本效益方面大大落后。这种新颖的制造方法提供了强大的竞争优势的可能性。工艺规模化的潜力使得在不到3年的时间内实现大直径3C晶圆成为可能。与4H和6H-SiC晶圆相比，使用Si衬底进行3C种子生长将确保成本与直径比的估计数量级优势。克服现有SiC技术的价格和晶圆尺寸限制将大大加快高功率和高频SiC器件的商业接受度。

This Small Business Technology Transfer (STTR) Phase I project aims at developing new material growth technology for manufacturing semiconductor substrates of cubic 3C-SiC polytype for high-power, high-frequency, high-temperature, and high-radiation hardness military, space, and commercial applications. The new process for SiC epitaxial growth utilizes novel mechanisms of gas phase and surface reactions. These mechanisms are provided by using halo-carbon growth chemistry replacing the traditional propane-based system. Applied to homoepitaxial growth of the 4H-SiC polytype, the new growth method resulted in defect-free epilayers at temperatures as low as 1350C, which is much lower than what was considered possible for high-quality growth. Simultaneously, a drastic increase of the growth rate in comparison to the propane-based growth was achieved at regular for 4HsiC growth temperatures. The halo-carbon growth promises to resolve critical problems impeding 3C-SiC commercialization such as morphology degradation by unfavorable homogeneous reactions, lattice mismatch-related defect generation, and growth rate reduction by silicon vapor condensation. Commercial supply of wafers of 3C-SiC polytype is not available today. Growing efforts to develop and commercialize 3?-SiC technology in Japan and Europe may put the wide band gap industry in the US significantly behind in cost-efficiency of SiC electronics. This novel fabrication method offers a possibility of a strong competitive advantage. The potential for process scaling makes it possible to achieve large-diameter 3C wafers in less than 3 years. Use of Si substrates for 3C seed growth will ensure an estimated order of magnitude advantage in cost-to-diameter ratio in comparison to 4H and 6H-SiC wafers. Overcoming the price and wafer size limitations of the existing SiC technologies will significantly speed up commercial acceptance of high-power and high frequencySiC devices.