The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 13, 2009
Filed:
Feb. 25, 2005
Naofumi Shinya, Takefu, JP;
Norio Yamagata, Takefu, JP;
Naofumi Shinya, Takefu, JP;
Norio Yamagata, Takefu, JP;
Shin-Etsu Chemical Co., Ltd., Chiyoda-Ku, Tokyo, JP;
Abstract
Provided is a surface-treated substrate in which the roughness of the surface of the substrate is controlled. The surface-treated substrate can form a magnetic recording medium in which head flying stability is maintained and which has a magnetic film that can achieve high recording densities. Also provided is a method for roughening the surface of the substrate. More specifically, provided is a surface-treated silicon substrate for a magnetic recording medium in which a surface used for forming a recording layer has 40 to 1000 protrusions per 1 μmwith a maximum height of 10 nm or less and an average roughness of 0.3 to 2.0 nm, and in which there are no defects or spots on any of the surface. Furthermore, provided is a method for manufacturing the surface-treated silicon substrate for the magnetic recording medium, comprising a step of etching a surface of a silicon substrate, wherein ultrasound is applied to the surface of the silicon substrate with the substrate shaken or rotated. Also provided is a magnetic recording medium, comprising the silicon substrate.