Abstract: Provided is a polishing composition capable of speeding up a mirror polishing in terms of polishing rate and the like, improving the smoothness and the flatness of a wafer surface of a semiconductor wafer after the mirror polishing, enabling mirror finishing with high processing accuracy, and having excellent storage stability. The polishing composition is for polishing a polishing target including a group III-V compound as a constituent component, and includes colloidal silica, an oxidizing agent, an oxidation accelerator for accelerating the oxidation reaction on the surface of the polishing target by the oxidizing agent, a stabilizer for controlling the accelerating action of the oxidation reaction on the surface of the polishing target by the oxidation accelerator, and water.

Abstract: A rolling apparatus having a width adjustment function includes a horizontal sleeve roll divided into two rolls in the axial direction and shrink-fitted over an arbor. Internal threads are formed in the inner circumference of one of the divided sleeve rolls. The arbor includes fluid passages for loading a fluid under high pressure between the sleeve roll and the arbor. A width-adjusting sleeve is movably mounted over the axial end portion of the arbor and external threads for formed in the inner side portion of the width-adjusting sleeve. The external threads of the width-adjusting sleeve are threadedly engaged with the internal threads of the sleeve roll. A clutch mechanism fixes the width-adjusting sleeve in a fixed position when a roll width adjustment is performed.