Patent ID: 7362454
Filing Date: 2008-04-22
Classification: G01B

Abstract:
1. A method for measuring the thickness of a thin film disk overcoat layer, the method comprising: radiating x-rays on a thin film disk comprising at least one base layer and an overcoat layer; collecting fluorescence data on electromagnetic radiation comprising Kα X-ray photon energy with wavelengths corresponding to selected materials fluoresced from the thin film disk; reflecting polarized light from a surface of the thin film disk corresponding to the overcoat layer; collecting ellipsometry data from the polarized light reflected from metal layers below the overcoat layer; correlating optical properties of metal layers below the overcoat layer with the fluorescence data, the optical properties comprising a composite index of refraction and a composite extinction coefficient; adjusting the optical properties used in the ellipsometry data to reflect metal layer variation due to metal layer composition and metal layer manufacturing using the correlated optical properties derived from the fluorescence data; and estimating the thickness of the overcoat layer using the adjusted optical properties to correct for errors in the ellipsometry data.