| 摘要 |
PURPOSE:To prevent a workpiece from being subjected to any damage by mix ing at least bleaching power, sodium tripolyphosphate and sodium sulfate into water, in the case of a polishing liquid used for polishing the mirror-like surface of a substrate made of monocrystal of gallium arsenide. CONSTITUTION:The mirror-like surface of a substrate 3 made of monocrystal of gallium arsenide is polished by means of polishing liquid formed by mixing about 0.4-4.4g of strong bleaching powder mainly consisting of calcium hypochlorite into a solution consisting of about 6.4g of sodium tripolyphosphate, about 7.2g of sodium sulfate and about 500ml of pure water. In this case, Ga2O3 and As2O3 are formed as a reaction product 4 on the surface of gallium arsenide 3 by aid of ClO<-> generated through dissociation of strong bleaching powder in pure water, the protruding portions of the reaction product 4 are swept off by polishing cloth 5 to get the surface of gallium arsenide 3 exposed, and a reaction product 6 is formed again. These processes are repeated alternately to form a flat and smooth mirror-like surface polishing state. A mirror-like surface polishing process of high accuracy can be carried out in this way, without giving any damage to a workpiece. |
