Recipe for successful Thin Film Measurements
Start with excellent raw data with optimized signal-to-noise ratio over the widest possible wavelength range, combine with physically valid models for analysis of the raw data.
RESULT: Accurate and precise measurements of the most challenging OCD and thin film structures that cover current and future applications.

Measurements are taken over the widest possible wavelength range either from 190nm -1,000nm or 190nm - 15,000nm.
Optical design involves n&ks patented reflective optics for which most of the photons (signal) are able to reach the detector, thus optimizing the signal-to-noise of the measured raw data.
The physically valid Forouhi-Bloomer (F-B) Dispersion Equations for n and k as functions of
wavelength, are utilized for thin film analysis. The F-B equations are combined with the physically valid Rigorous Coupled Wave Analysis (RCWA) for analysis of OCD structures (2D trenches and 3D holes).

Thin Film Applications
Wafer Bonder
Original Papers on Core Technology
Optical Properties of Crystalline Semiconductors and Dielectrics
Source: Physical Review B, Vol. 38, Np. 3, 1865 (1988)
Authors: A.R. Forouhi, I. Bloomer
Abstract: Second paper which introduces the Forouhi-Bloomer Dispersion Equations. Shows that there is excellent agreement with the FB Model and the characterization for crystalline Si, Ge,GaP, GaAs, GaSb, InP, InAs, InSb, SiC, cubic C, and a-SiO2, over a wide range of energies

Optical Dispersion Relations for Amorphous Semiconductors and Amorphous Dielectrics
Source: Physical Review B, Vol. 34, No. 10, 7018 (1986)
Authors: A.R. Forouhi, I. Bloomer
Abstract: Original paper which introduces the Forouhi-Bloomer Dispersion Equations and the excellent agreement with experimentally measured results of n and k for amorphous silicon, hydrogenated amorphous silicon, amorphous silicon nitride and titanium dioxide.

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n&k Technology, Inc.
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CWI Technical Sales    Phone: 732-536-3964    Fax: 732-536-0495   

up to 450mm. up to 200mm. Manual Load.
"Standard" films such as SiOx, SiNx, Poly-Si, a-Si:H, SiCx, a-C:H, TiNx, AlOx
Transparent conductor such as ITO
Photoresists, ARCs, polymers, polyimides
Thin Metal Films (less than ~ 800 in general): Al, CrSi, Ta, Ti, W, Cu, Fe, Au, Ag
High-k films
Low-k films
Chalcogenide films
Inhomogeneous films
A variety of complex film stacks, including
- Multi-Layer Film Stacks with Inhomogeneous Under-Layer
- Multi-Layer Film Stacks with Unknown Under-Layer
Ultra-Thin Films (down to a few ), e.g., a Monolayer of Graphene
Ultra-Thin Residual Layers
Films Deposited on Rough Surfaces
Films on GaAs, SiC, AlTiC
Surface and interface roughness of thin films
Energy Band Gap
Compositon (e.g., %Ge in SiGex; %N, %H, %O in SiOxNx:H,
%N in TiNx, etc.)
Crystallinity (e.g., degree of crystallinity of Poly-Si or GST)
Zeta Instruments 3D Optical Profiler