Patent ID: 6275297
Filing Date: 2001-08-14
Classification: G01N

Abstract:
A method of measuring a depth geometry of a structure on a semiconductor substrate including a plurality of recessed and non-recessed portions, wherein one of said recessed and non-recessed portions includes a reference interface, and wherein at least one of said recessed and non-recessed portions has a dielectric layer thereon, comprising the steps of:irradiating said recessed and non-recessed portions of the substrate with a broadband light source;detecting a first spectral component comprising light reflected from said recessed portions and a second spectral component comprising light reflected from said non-recessed portions, wherein one of the first and second components further comprises a third component comprising light reflected from said dielectric layer;storing data including spectral reflectance information of said first, second and third components; anddetermining a depth geometry of said recessed portions relative to said reference interface based on an interferometric analysis of said data including spectral reflectance information of each of said first, second and third components.