Patent ID: 7900497

Claim:
A method of measuring a surface finish of a magnetic media, comprising: (a) forming a magnetic media on a surface of a disk, the magnetic media having a topography with valley depths; (b) placing the disk on a support with the surface facing up; (c) applying a liquid to at least a portion of the surface; (d) placing a substrate on the surface to cover at least a portion of the surface is wetted by the liquid; (e) curing the liquid to form a solid; (f) removing the substrate from the disk such that the solid remains on the substrate and defines an inverse replica of at least a portion of the magnetic media on the surface of the disk; (g) measuring peak heights of the inverse replica to derive measurements of the valley depths in the topography of the magnetic media on the disk; and (h) predicting a corrosion performance of the magnetic media based on the derived measurements of the valley depths in the topography of the magnetic media on the disk.