异质外延单晶金刚石的研究进展

Recent progress in hetero-epitaxial growth of the single-crystal diamond

单晶金刚石具有优异的力、声、热、光、电等性质,而异质外延工艺是制备大尺寸单晶金刚石的一种重要手段.本文以CVD工艺所采用的c-BN、Pt、Si、SiC、Ir复合衬底等不同类型异质衬底为主线,以国内外开展该研究的代表性团队所取得主要成果为基础,对该领域多年来的发展历程、最新进展开展评述,主要涉及偏压增强形核技术及晶种处理后高温退火技术等高密度外延金刚石形核工艺及机理,基于台阶流动和向错形成机理的织构生长晶界湮灭过程与工艺调控,横向外延过度生长和离轴衬底生长等用于位错密度降低的工艺等内容,并在最后对该领域的未来发展做出展望.

Single-crystal diamonds have excellent mechanical,thermal,optical,and electrical properties,and heteroepitaxy is a critical method for preparing large-scale single-crystal diamonds.Considering different types of substrates,such as c-BN,Pt,Si,Si C and Ir multilayer substrate used in the CVD process as the mainline and based on the key findings of the main teams at home and abroad,this paper reviews the development course and the latest progress in this field,mainly involving high-density epitaxial diamond nucleation processes and mechanisms,such as bias-enhanced nucleation and high-temperature annealing after seed treatment,grain boundary annihilation and texture growth processes based on step-flow and the disclination formation mechanism,epitaxial lateral overgrowth and off-axis growth for reducing dislocation.Finally,the current status is summarized and future development is proposed.