SiC单晶是第三代宽禁带半导体材料。如何降低SiC单晶的生产成本和提高其质量是目前国内外研究的焦点。助溶剂法能在低温下生长高质量的SiC单晶，有希望降低SiC单晶的成本，但如何提高其生长速度是需解决的关键问题。本项目采用新型助溶剂RE（稀土金属Pr、La或Nd）进行低温（≤1823 K）高速（接近PVT法）生长高质量（晶体缺陷少）SiC单晶的研究。通过硅热还原稀土氧化物制备Si-RE合金作为提高C溶解度的助溶成分；通过热力学研究确定Si-RE-C熔体生长SiC单晶的前提条件（低温生长条件），从理论上得到适合低温高速生长SiC单晶的最佳熔体；用该最佳熔体进行SiC单晶生长的动力学机理研究，揭示SiC单晶生长的限制性环节（高速生长条件）；将得到的SiC晶体进行缺陷分析，结合热力学和动力学研究，揭示缺陷产生的机理（高质量晶体生长条件）。本项目研究成果将为助溶剂法生长SiC单晶补充重要的理论依据。

SiC single crystal is a wide band-gap semiconductor material. Recently, How to reduce its cost and improve the quality attracts researchers’ attention. Solution growth is a method that can grow high-quality SiC single crystal at low temperature, which can reduce the cost of SiC single crystal. However, how to enhance its growth rate is one of the difficulties that have to break through. This research project will study on rapid growth (growth rate is close to that of PVT method) of high-quality SiC crystal (less defects) at low temperature (≤1823 K) using RE (rare earth metals, Pr, La or Nd) containing solvents. The Si-RE alloys, which are employed as solvents to enhance the solubility of C, will be prepared by reducing rare earth oxides with silicon. Thereafter, thermodynamic study will be carried out to determine the preconditions for SiC growth at low temperature using Si-RE-C solvents (low-temperature growth conditions), and chose the optimal solvent for rapid growth of SiC at low temperature theoretically. Then, the selected optimal solvent will be employed to investigate the dynamic mechanism for growth of SiC, and the restrictive link (high-speed growth conditions) for rapid growth of SiC will be revealed. Finally, the mechanism of defects formation in the obtained SiC single crystals will be discovered (high-quality growth conditions) by combining the thermodynamic and dynamic studies. The results of this project will enrich the important theory for growth of SiC single crystal using solvents.