Image scanning ellipsometry for measuring nonuniform film thickness profiles

A novel technique to measure the two-dimensional (2-D) thickness profile of a nonuniform, thin film, from several nanometers to several micrometers, in a steady state as well as in a transient state has been developed and tested. Image scanning ellipsometry (ISE) is a full-field imaging technique that one can use to study every point on the surface simultaneously with high spatial resolution and thickness sensitivity, i.e., it can measure and map the 2-D film thickness profile. The primary purpose of this paper is to present the basic concept of ISE and a demonstration of its use.