In the semiconductor industry, infrared light can be used to characterize materials such as thin films and periodic trench structures. By measuring the reflectance of light from the surface of a semiconductor wafer, the index of refraction (n) and the extinction Coefficient (k) can be determined via the Forouhi-Bloomer dispersion equations. The reflectance from the infrared light can also be used to determine the critical dimension, depth, and sidewall angle of high aspect ratio trench structures. COUNT 5
QSN1 What letter represents the index of refraction? ANS1 n QSN2 What letter represents the extinction Coefficient? ANS2 k QSN3 What equations are used to figure out the index of refraction and extinction Coefficient? ANS3 Forouhi-Bloomer dispersion QSN4 Along with critical dimension and depth, what can the infrared light reflectance be used to determine in regard to high aspect ratio trench structures? ANS4 sidewall angle QSN5 What reflectance is measured from a semiconductor wafer's surface to determine the index of refraction? ANS5 light