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Publication Citation: MEMS Young's Modulus and Step Height Measurements with Round Robin Results

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Author(s): Janet M. Cassard; Richard A. Allen; Craig D. McGray; Jon C. Geist;
Title: MEMS Young's Modulus and Step Height Measurements with Round Robin Results
Published: September 30, 2010
Abstract: This paper presents the results of a microelectromechanical systems (MEMS) Young s modulus and step height round robin experiment, completed in April 2009, which compares Young s modulus and step height measurement results at a number of laboratories. The purpose of the round robin was to provide data for the precision and bias statements of two related Semiconductor Equipment and Materials International (SEMI) standard test methods for MEMS. The technical basis for the test methods on Young s modulus and step height measurements are also provided in this paper. Using the same test method, the goal of the round robin was to assess the repeatability of measurements at one laboratory, by the same operator, with the same equipment, in the shortest practical period of time as well as the reproducibility of measurements with independent data sets from unique combinations of measurement setups and researchers. Both the repeatability and reproducibility measurements were done on random test structures made of the same homogeneous material. The average repeatability Young s modulus value (as obtained from resonating oxide cantilevers) was 64.2 GPa with 95 % limits of 10.3 % and an average combined standard uncertainty value of 3.1 GPa. The average reproducibility Young s modulus value was 62.8 GPa with 95 % limits of 11.0 % and an average combined standard uncertainty value of 3.0 GPa. The average repeatability step height value (for a metal2-over-poly1 step from active area to field oxide) was 0.477 m with 95 % limits of 7.9 % and an average combined standard uncertainty value of 0.014 m. The average reproducibility step height value was 0.481 m with 95 % limits of 6.2 % and an average combined standard uncertainty value of 0.014 m. In summary, this paper demonstrates that a reliable methodology can be used to measure Young s modulus and step height. Furthermore, a micro and nano technology (MNT) 5-in-1 standard reference material (SRM) can be used by
Citation: Journal of Research of the National Institute of Standards and Technology
Volume: 115
Pages: pp. 303 - 342
Keywords: interferometry; microelectromechanical systems; round robin; standard test methods; step height; test structure; vibrometry; Young s modulus
Research Areas: International Standards
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