| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polishing method of a magnetic disk base board capable of eliminating a head collision by remaining of colloidal silica, by further reducing surface roughness. <P>SOLUTION: A surface plated layer of a plated base board 59 is finished and polished while supplying an abrasive 61 including the colloidal silica. A polishing quantity is desirably set to 500 nm or more, and main processing pressure is set to 80 g/cm<SP>2</SP>or more. After finishing finishing polishing, a valve 64 is closed, and the abrasive 61 including the colloidal silica on the base board 59 is easily removed by supplying pure water 62 by opening a valve 65 for supplying the pure water. Next, an abrasive supply valve 64 is opened, and cleaning polishing is performed while supplying an acid etching agent using a general organic acid without the colloidal silica compounded for the cleaning polishing. The polishing quantity is desirably set to 1 nm or more, and the main processing pressure is set to 30 g/cm<SP>2</SP>or less. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
