Super smooth surface figure control for large single crystal silicon mirror

In Chemical-Mechanical polishing experiments we produced optical quality super smooth surfaces on singlecrystal silicon, but cannot insure the surface figure. In order to avoid the alveoli and achieve a good optical surface, a continuously adding slurry method with digging four welldistributed holes was used and advanced in this article. The best results were obtained as 0.268λ peak to peak surface (its diameter 152.4mm) and rms 0.065λ using this method.