单晶SiC的化学机械抛光及其增效技术研究进展

Research progress of chemical mechanical polishing and its efficiency-enhancement technology for single crystal silicon carbide

摘要:

为了解决传统SiC化学机械抛光(CMP)加工效率低的问题，针对单晶SiC表面抛光质量和材料去除率指标，综述了应用传统碱性抛光液、混合磨粒抛光液及含强氧化剂抛光液对单晶SiC进行化学机械抛光的研究现状；为了提高SiC-CMP的化学和机械两方面作用，对SiC-CMP催化辅助增效技术、SiC电化学机械抛光(ECMP)技术、固结磨料抛光、光催化辅助抛光等增效新技术进行了系统综述；对SiC-CMP及其增效技术进行了分析、讨论，指出了当前的研究难点，展望了进一步提高单晶SiC抛光效率的研究方向.

Abstract:

Chemical mechanical polishing (CMP), now regarded as the only method to obtain whole-wafer planarization and super-smooth surface without sub-surface defects, is usually employed as the final processing method for silicon carbide (SiC) wafer, but the processing efficiency of conventional SiC-CMP is too low to fulfill the current requirement. Aiming at surface quality and material removal rate (MRR) of polished single crystal SiC wafer, the current state of SiC-CMP research is discussed and categorized by CMP using different slurries, e.g. conventional alkaline colloidal silica base slurry, mixed abrasives slurry and slurries with strong oxidizers, respectively. Then from the viewpoint of improving the mechanical role, as well as the chemical one of CMP, the existing efficiency-enhancement methods of SiC-CMP, including the catalyst assisted polishing, electrochemical-mechanical polishing (ECMP), fixed abrasive polishing, and photo-catalyst assisted polishing are extensively reviewed and discussed. Analyses and discussions are conducted from the reviewed researches of SiC-CMP and its related efficiency-enhancement methods, the difficulties and future direction for further improvement on polishing MRR of single crystal SiC are proposed.