LBO晶体超光滑表面抛光机理

Mechanism of Super Smooth Surface Polishing for LBO Crystal

胶体SiO2抛光LBO晶体获得无损伤的超光滑表面,结合前人对抛光机理的认识,探讨了超光滑表面抛光的材料去除机理,分析了化学机械抛光中的原子级材料去除机理。在此基础上,对胶体SiO2抛光LBO晶体表面材料去除机理和超光滑表面的形成进行了详细的描述,研究抛光液的pH值与材料去除率和表面粗糙度的关系。LBO晶体超光滑表面抛光的材料去除机理是抛光液与晶体表面的活泼原子层发生化学反应形成过渡的软质层,软质层在磨料和抛光盘的作用下很容易被无损伤的去除。酸性条件下,随抛光液pH值的减小抛光材料的去除率增大;抛光液pH值为4时,获得最好的表面粗糙度。

Experiment phenomena of colloidal SiO2 polishing LBO crystal were observed and concluded. Analyzing the understanding of previous polishing mechanism, our comprehension and hypothesis of material removal mechanism of super smooth surface polishing are enunciated. And the material removal mechanism of chemical mechanical polishing at atomic level is described. On this basis, we circumstantiate material removal mechanism of colloidal SiO2 polishing LBO crystal and formation of super smooth surface, and study the relationship among pH of the slurry and material removal rate and surface roughness. The mechanism of material removal is that passing soft layer which the chemical reaction between polishing slurry and active atomic layer of crystal surface generates is easily removed. In acidic condition, the decrease pH of slurry results in the increase of material removal rate. The best surface roughness is obtained when pH of slurry is 4.