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Publication Citation: Intercomparison between optical and x-ray scatterometry measurements of FinFET structures

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Author(s): Paul Lemaillet; Thomas A. Germer; Regis J. Kline; Daniel F. Sunday; Chengqing C. Wang; Wen-Li Wu;
Title: Intercomparison between optical and x-ray scatterometry measurements of FinFET structures
Published: April 08, 2013
Abstract: In this paper, we present a comparison of profile measurements of vertical field effect transistor (FinFET) fin arrays by optical critical dimension (OCD) metrology and critical dimension small angle X-ray scattering (CD-SAXS) metrology. Spectroscopic Muller matrix elements measurements were performed at various azimuthal angles for OCD, and X-ray diffraction intensities were collected for different incident angles in CD-SAXS measurements. A common trapezoidal model was used to compute the OCD and CD-SAXS signatures, using rigorous coupled wave (RCW) analysis and a 2D Fourier transform, respectively. Profile parameters, some material parameters, and instruments parameters were adjusted by a non-linear fitting procedure of the data. Results from both measurement techniques were compared and found in reasonable agreement with one another, although some of the parameters have differences that exceed the estimated uncertainties.
Proceedings: Metrology, Inspection, and Process Control for Microlithography XXVII
Location: San Jose, CA
Dates: February 24-28, 2013
Keywords: CD-SAXS; ellipsometry; OCD; optical critical dimension; scatterometry; small angle x-ray scattering
Research Areas: Dimensional Metrology, Optical Metrology, Optical Properties of Materials, Characterization, Nanometrology, and Nanoscale Measurements