高温溶液法生长SiC单晶的研究进展

碳化硅(SiC)作为第三代半导体材料,不仅禁带宽度较大,还兼具热导率高、饱和电子漂移速率高、抗辐射性能强、热稳定性和化学稳定性好等优良特性,在高温、高频、高功率电力电子器件和射频器件中有很好的应用潜力。高质量、大尺寸、低成本SiC单晶衬底的制备是实现SiC器件大规模应用的前提。受技术与工艺水平限制,目前SiC单晶衬底供应仍面临缺陷密度高、成品率低和成本高等问题。高温溶液生长(high temperature solution growth, HTSG)法生长SiC单晶具有晶体结晶质量高、易扩径、易实现p型掺杂等独特的优势,有望成为大规模量产SiC单晶的主要方法之一,目前该方法的主流技术模式是顶部籽晶溶液生长(top seeded solution growth, TSSG)法。本文首先回顾总结了TSSG法生长SiC单晶的发展历程,接着介绍和分析了该方法的基本原理和生长过程,然后从晶体生长热力学和动力学两方面总结了该方法的研究进展,并归纳了该方法的优势,最后分析了TSSG法生长SiC单晶技术在未来的研究重点和发展方向。

Research Progress on the Growth of SiC Single Crystal via High Temperature Solution Growth Method

As a third-generation semiconductor material,silicon carbide(SiC)has excellent properties such as wide bandgap,high thermal conductivity,high saturation electron drift velocity,strong radiation resistance,good thermal and chemical stability,et al.It has great application potential in high temperature,high power,high frequency power electronic devices and radio frequency devices.The production of high-quality,large-size,and low-cost SiC single crystal substrates is a prerequisite for large-scale applications of SiC devices.However,the supply of SiC single crystal substrates still faces some challenges,such as high defect density,low yield and high cost.High temperature solution growth(HTSG)technique,with top seeded solution growth(TSSG)as the main technical model at present,has advantages of fabrication of SiC with low defects density,easy to enlarge diameter,and easy to obtain p-type doping.In the future,it is expected to become one of the mainstream technologies to mass produce SiC single crystals.In this paper,the development of SiC single crystal grown by TSSG is reviewed firstly.Then the principle and growth process of SiC single crystal growth by TSSG are introduced and analyzed.The research progress of TSSG for SiC single crystal growth is summarized from crystal growth thermodynamics and kinetics.The unique advantages of this technology are summarized.Finally,the future research direction and challenges of this method are given.