Optical material has increasingly been used for different applications due to its superior properties. The performance of these is affected by the polishing process and to achieve the better finish. Germanium has desirable properties such as light weight, good thermal conductivity, high strength,excellent infrared refractive index and has civilian applications. The polishing of the Germanium for high finish applications is challenging. Conventional polishing is the most refined finishing processes which target the finest surface. There are different parameters (speed, load, abrasive concentration, pH) which effect the polishing process and it is often required to increase the polishing time in order to improve the roughness and maintain desired surface integrity. This work aims to study the surface roughness of Germaniumby conventional polishing. The DOE technique using Taguchi has been used to optimize the parameters. In this experiment, cerium oxide slurry with different concentration is used with deionised water to polish Germanium on a polyurethane pad. The result indicates that polishing on polyurethane pad with cerium slurry and speed of polisher spindle has significant effect on surface roughness.

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Germanium Polishing Taguchi's Method Surface Roughness