Method of determining refractive indices of transparent and absorbent films

摘要

The method involves using a spectral ellipsometer with a PCSA configuration. The Fourier coefficients, s1 and s2 are determined using a nonideal compensator. The values of cos 2 theta , cos DELTA , and sin DELTA for the four coefficients s1

, s2

, s1 and s2 are determined using mathematical relationships: s1 = {A- C2 theta }/{1 - C2 theta A} and s2 = {s2 theta s ETA + DELTA (D<2> = L<2>)2}/{1 - C2 theta A}, where ETA = 90 deg , A,D and L are instrument constants, Cx is an abbreviation for cos(x) and Sx is an abbreviation for sin(x). The axial positions, theta

, theta , and phase shifts DELTA

, DELTA are derived from the trigonometric functions using conventional relationships and the coating thickness is derived from the axial position and phase shift.