Patent ID: 9595481
Date: 2017-03-14
CPC Classifications: G01N,G01R,H01L

Claim:
1. A non-transitory, computer-readable medium, comprising: code for causing a computer to receive a spectral response of an unfinished, multi-layer semiconductor wafer across a spectral range; code for causing the computer to determine a plurality of parameter values of an optical dispersion model of one or more layers of the multi-layer semiconductor wafer based at least in part on the spectral response, wherein the optical dispersion model includes a Cody-Lorentz model having a first derivative of a dielectric function with respect to energy that is continuous at the Urbach transition energy of the Cody-Lorentz model, wherein the rate of attenuation of the Urbach function, E  wherein  and wherein E code for causing the computer to store the plurality of parameter values of the optical dispersion model in a memory.