Accurate Size Measurement of Monosize Calibration Spheres by Differential Mobility Analysis.
Accurate Size Measurement of Monosize Calibration
Spheres by Differential Mobility Analysis.
(555 K)
Mulholland, G. W.; Fernandez, M. G.
Characterization and Metrology for ULSI Technology.
International Conference, 1998. CP449. Proceedings.
March 1998, Gaithersburg, MD, American Institute of
Physics, Seiler, D. G.; Diebold, A. C.; Bullis, W. M.;
Shaffner, T. J., Editor(s)(s), 819-823 pp, 1998.
Keywords:
mobility; particle size; polystyrene
Abstract:
A differential mobility analyzer was used to measure the
mean particle size of three monosize suspensions of
polystyrene spheres in water. Key features of the
experiment to minimize the uncertainty in the results
include developing a recirculating flow to ensure equal
flows into and out of the classifier, an accurate
divider circuit for calibrating the electrode voltage,
and use of the 100.7 nm NIST SRM for calibrating the
flow of the classifier. The measured average sizes and
expanded uncertainties with a coverage factor of 2 are
92.4 mn + 1.1 nm, 126.9 nm + 1.4 nm, and 217.7 nm + 3.4
nm. These calibration sizes were characterized by NIST
to improve the calibration of scanning surface
inspection systems.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899