METHOD FOR DETERMINING FILM THICKNESS Russian patent published in 2023 - IPC G01B11/06 

FIELD: optical-physical measurements.

SUBSTANCE: invention relates to the field of optical-physical measurements, based on ellipsometry, to methods for measuring and controlling film thickness. The method for determining the film thickness includes, for a substrate material that does not contain the film under study, the measurement or calculation of the values ​​of ψ and Δ based on the known data on the optical properties of the corresponding materials, the nomogram is calculated using the equation ρ=tgψe^iΔ using the data n and K for the material to be determined of the substrate and possible numerical sets n, d, K for the contamination film, the measurement results of the ellipsometric parameters Δ and ψ of the corresponding substrate material in the plane are fixed in the form of a curve, the results of ellipsometric measurements are compared with the data of the results of calculating the values ​​of ψ and Δ for the corresponding material that does not contain the film under study, and if the obtained Δ and ψ differ from these results calculation of the values ​​of ψ and Δ for the corresponding material that does not contain the investigated film, the thickness and refractive index of the contamination film by means of a nomogram for the corresponding material.

EFFECT: simplification of the process of determining the film thickness while expanding the possibility of its measurement on an optical element made of different materials.

2 cl, 4 dwg, 2 tbl