| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an abrasive which, with respect to abrasion of a glass stock and a semiconductor device, contains no contaminants, provides an im proved abrasion speed as compared to a silica abrasive, while maintaining a surface processed state equal to that obtained using a silica abrasive, shows reduced adhesion of a abrasive grains on the abraded surface and can contribute to the improvement of productivity, by using a ceric oxide powder having spe cific properties. SOLUTION: This abrasive comprises a cerium oxide powder in which a number average particle diameter of a primary particle is 0.01-0.5μm and the half-value width 2θ( deg.) of an angle 28.6 deg. (111 face) of diffraction in X-ray diffraction is 0.7-0.15 deg.. In order to prepare a slurry of the abrasive using the cerium oxide as an abrasive grain, the cerium oxide is preperably contained 0.5-30 wt.%, preferably 1-10 wt.% to a whole amount of the abradant. A stock powder of the cerium oxide can be prepared by various methods. In a hydrothermal method, a base such as ammonia water or the like is added to an aqueous solution of a cerium salt to neutralize the solution and a precipitation is deposited, followed by heating the resulting product in a pressure vessel to crystallize the product.</p> |
