Silicon substrate for magnetic recording medium and magnetic recording medium

Abstract

To provide a substrate which is not substantially chipped or cracked on the substrate end faces even when the substrate is a silicon substrate made of a brittle material, and provide a substrate which prevents dust raising from the substrate end faces and prevents dust raising due to rubbing with a processing cassette. A silicon substrate for a magnetic recording medium is formed by setting the lengths L of chamfered portions between the main surfaces of the substrate and the outer circumferential side end face to 0.1±0.03 mm and setting the angles α between the main surfaces and the chamfered portions between the main surfaces and the outer circumferential side end face to 45 degrees ±5 degrees. It is also possible for a curved portion with a radius of 0.01 mm or more and less than 0.3 mm is interposed between the main surfaces and the outer circumferential side chamfered portions of the substrate.

Dependencies are inferred from the claim text.