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Semiconductor Measurement Technology: Thin Film Reference Materials Development; Final Report for CRADA CN-1364



Barbara J. Belzer, K Eberhardt, Deane Chandler-Horowitz, James R. Ehrstein, P. Durgapal


Independent single-wavelength ellipsometric measurements of thermally grown silicon dioxide thin films on silicon substrates and data analyses were compared between two laboratories (NIST and VLSI Standards, Inc.) under a Cooperative Research and Development Agreement. The goal was to clarify the problems associated with improving the measurement and modeling uncertainties associated with thickness determinations. This was a necessary element in being able to produce in a more timely manner very thin, traceable film standards (less than 10 nm) that can be used in the calibration and setup of optical metrology instruments used in the semiconductor industry. The results of the intercomparison show that there are small systematic differences in the values of the ellipsometric parameters [Δ] and [Psi] between the two laboratories along with occasional larger differences. Artificial differences in the calculated film thicknesses exist because of the use of different algorithms for computation. A single-layer model and a fixed value of the oxide index of refraction are assumed for the primary comparison in this collaboration, but a two-layer model of the oxide/interface/substrate system is also presented.
Special Publication (NIST SP) - 400-100
Report Number


calibration ellipsometry, metrology, traceability, silicon, silicon dioxide, standards, thin films


Belzer, B. , Eberhardt, K. , Chandler-Horowitz, D. , Ehrstein, J. and Durgapal, P. (1998), Semiconductor Measurement Technology: Thin Film Reference Materials Development; Final Report for CRADA CN-1364, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 18, 2024)


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Created March 31, 1998, Updated October 12, 2021