Research on chemical mechanical polishing of KTiOPO4crystal

With the development of laser equipment industry, higher requirements were put forward for the surface quality of $\boldsymbol{KTiOPO_{4}}$ (KTP). With SiO 2 abrasive, oxidant hydrogen peroxide, pH value regulator KOH and citric acid, chemical mechanical polishing (CMP) of KTP crystal was carried out, and the surface roughness was taken as the assessment indicator. The components of the polishing slurry were optimized in the research process. Provided that diameter of $\boldsymbol{SiO_{2}}$ is 20 nm, mass fraction of $\boldsymbol{SiO_{2}}$ is 10 %, pH value is 10 and $\boldsymbol{H_{2}O_{2}}$ is 3 wt%, the ultra-smooth crystal surface (less than 0.2 nm) with good uniformity is obtained.