酸性条件下的CdSe波片抛光工艺研究

Study on Polishing Process of CdSe Wave Plate under Acidic Conditions

利用自然解理和X射线衍射仪对气相法制备的大尺寸CdSe单晶定向,并沿光轴方向切割出20 mm×20 mm×3 mm的CdSe波片初胚。采用酸性化学机械抛光方法对波片初胚进行表面处理,将5%溴甲醇与W0.25(粒度为0.25μm)的金刚石悬浮液按1∶10的体积比混合并用盐酸调节抛光液的pH值。结果表明:当抛光液pH=5时,样品表面平整划痕较少,粗糙度约为0.8 nm,平行度公差f=0.00275 mm,样品的红外透过率在2-20μm波段均达到65%-70%,其吸收系数在0.01~0.06

The orientation of large-size CdSe crystal grown by the vapor sublimation method, was determined by natural cleavage and X-ray diffract meter. The embryo of CdSe wave plates with size of 20 mm × 20 mm × 3 mm were cut in the direction of the optical axis. The surface treatment of the wave plate was treated by acid chemical mechanical polishing. The slurry was 5% bromine methanol and W0. 25（the particle size is 0. 25 μm） diamond suspension press 1 ∶ 10 the volume ratio of the mixture,its pH value was adjusted by hydrochloric acid. Results show that when the pH was 5,the surface without scratches was flat,the roughness was about 0. 8 nm,the parallel tolerance was 0. 00275 mm,the infrared transmittance was 65%-70% in the range of 2-20 μm,and its absorption coefficient was between 0. 01 cm^-1 and 0. 06 cm^-1.