Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Statistical methods for MGI metrology

Summary

We are developing statistical methods to enable measurement science and metrology for MGI (project started in 2011).

Description

We focus on research and development of statistical methods to enable new measurement science and metrology relevant to MGI.  In particular, we illustrate our methods for examples from near-field scanning probe microwave microscopy (NSSM) for characterization, development, and modeling of novel materials, and the electronic measurement of the the Boltzmann constant based on Johnson noise thermometry. We expect our methods to apply to a broad range of metrological and material characterization studies relevant to MGI.

  • Development
  • Development

Major Accomplishments

Data Dissemination

Raw and processed near-field scanning microwave microscopy (NSSM) images of a GaN nanowire on the MML data repository at https://materialsdata.nist.gov/dspace/xmlui/handle/11256/783.

Publications (archival journals)

  • K.J. Coakley and J. Qu, ``Spectral model selection in the electronic measurement of the Boltzmann constant by Johnson  noise thermometry," accepted for publication in Metrologia.  http://arxiv.org/abs/1606.05907
  • S. Berweger, P.T. Blanchard, M.D. Brubaker, K.J. Coakley, N.A. Sanford, T.M. Wallis, K.A. Bertness and P. Kabos, ``Near-field control and imaging of free charge carrier variations in GaN nanowires," Appl. Phys. Lett. 108, 073101 (2016); http://dx.doi.org/10.1063/1.4942107
  • K.J. Coakley, A. Imtiaz, T.M. Wallis, J.C. Weber, S. Berweger, and P. Kabos, "Adaptive and robust statistical methods for processing near-field scanning microwave  microscopy images," Ultramicroscopy 150 (2015):1-9.
  • J.C. Weber, P.T. Blanchard, A.W. Sanders, J.C. Gertsch, S.M. George, S. Berweger, A. Imtiaz, K.J. Coakley, T.M. Wallis, K.A. Bertness, P. Kabos, N.A. Sanford and V.M. Bright, "GaN nanowire coated with atomic layer deposition of tungsten: a probe for near-field scanning microwave microscopy," Nanotechnology 25, no. 41 (2014):415502.
  • J.C. Weber, P.T. Blanchard, A.W. Sanders, A.Imtiaz, T M. Wallis, K.J. Coakley, K.A. Bertness, P. Kabos, N.A. Sanford, and V.M. Bright, "Gallium nitride nanowire probe for near-field scanning microwave microscopy," Applied Physics Letters 104, no. 2 (2014): 023113.
  • A. Imtiaz, T.M. Wallis, J.C. Weber, K.J. Coakley, M.D. Brubaker, P.T. Blanchard, K.A. Bertness, N.A. Sanford, and P. Kabos, "Imaging the pn junction in a gallium nitride nanowire with a scanning microwave microscope," Applied Physics Letters 104, no. 26 (2014): 263107.
  • J.C. Weber, J.B. Schlager, N.A. Sanford, A. Imtiaz, T.M. Wallis, L.M. Mansfield, K.J. Coakley, K.A. Bertness, P. Kabos, and V.M. Bright, "A near-field scanning microwave microscope for characterization of inhomogeneous photovoltaics," Review of Scientific Instruments 83, no. 8 (2012): 083702.

Publications (conference proceedings)

  • J.C. Weber, N.A. Sanford, P.T. Blanchard, A.W. Sanders, A. Imtiaz, T.M. Wallis,K.J. Coakley, K.A. Bertness, P. Kabos, and  V. M. Bright, ``Broadband Characterization of a GaN NW Probe  for Near-Field Scanning Microwave Microscopy" The 27th International Conference on Micro Electro Mechanical Systems (MEMS 2014), San Francisco, January 26-30, 2014
  • J.C. Weber, K. A. Bertness, J.B. Schlager, N.A. Sanford, A. Imtiaz, T.M. Wallis, P. Kabos, K.J. Coakley, V.M. Bright, L.M. Mansfield, Microwave Near-Field Probes for Photovoltaic Applications, Proceedings of the 37th IEEE Photovoltaic Specialists Conference, Seattle, WA, 06/19/2011 to 06/24/2011

Invited Talk

  • S. Berweger, J. Weber, T. M. Wallis, K. Stupic, S. Russek, P. Kabos, and K. Coakley, "Metrology with scanning microwave microscopy," Nanoscale Measurements with Scanning Probe Microscopy, London, England, February 5, 2015.

Others

  • Development of machine learning methods for model selection and uncertainty quantification for electronic measurement of the Boltzmann constant by Johnson Noise Thermometry.
  • Development of robust machine learning methods for extracting signals from NSSM images of magnetic and electronic  materials.
Created October 24, 2017, Updated March 21, 2019