Abstract

From a series of ellipsometric measurements it is now possible to obtain uniquely all of the optical parameters of the system; absorbing substrate+nonabsorbing surface film. The method utilizes the fact that the reflectance of such a system at normal incidence remains essentially constant for a small but finite range of surface-film thicknesses. Furthermore, it hinges on the fact that the ellipsometric parameters Δ and ψ, measured on different film thicknesses grown on the same sample, are compatible with only one choice of the complex refractive index n₂+ik₂ of the substrate and the refractive index n₁ of the film. Measurements on chemically etched samples of silicon yield n₂ = 4.05₂ and k₂ = 0.02₉, in agreement with the results of earlier workers. Measurements on cleaved samples of silicon, on the other hand, reveal that the true values are n₂ = 4.14₀±0.02 and k₂ = 0.03₄±0.01 for 5461 Å.

© 1969 Optical Society of America

Generalized Ellipsometric Method for the Absorbing Substrate Covered with a Transparent-Film System. Optical Constants of Silicon at 3655 Å*

Samuel S. So and K. Vedam
J. Opt. Soc. Am. 62(1) 16-23 (1972)

Simultaneous and Independent Determination of the Refractive Index and the Thickness of Thin Films by Ellipsometry*

K. Vedam, R. Rai, F. Lukes, and R. Srinivasan
J. Opt. Soc. Am. 58(4) 526-532 (1968)

Effect of a Thin Surface Film on the Ellipsometric Determination of Optical Constants*

D. K. Burge and H. E. Bennett
J. Opt. Soc. Am. 54(12) 1428-1433 (1964)

Simple Method for the Determination of Optical Constants of Absorbing Materials

E. Schmidt
Appl. Opt. 8(9) 1905-1908 (1969)

New Ellipsometric Method for the Determination of the Optical Constants of Thin Films and Surfaces*†

S. C. Som and Chitralekha Chowdhury
J. Opt. Soc. Am. 62(1) 10-15 (1972)