Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

A tabletop x-ray tomography instrument for nanometer-scale imaging: demonstration of the 1,000-element transition-edge sensor subarray



Paul Szypryt, Nathan J. Nakamura, Dan Becker, Douglas Bennett, Amber L. Dagel, W.Bertrand (Randy) Doriese, Joseph Fowler, Johnathon Gard, J. Zachariah Harris, Gene C. Hilton, Jozsef Imrek, Edward S. Jimenez, Kurt W. Larson, Zachary H. Levine, John Mates, Daniel McArthur, Luis Miaja Avila, Kelsey Morgan, Galen O'Neil, Nathan Ortiz, Christine G. Pappas, Dan Schmidt, Kyle R. Thompson, Joel Ullom, Leila R. Vale, Michael Vissers, Christopher Walker, Joel Weber, Abigail Wessels, Jason W. Wheeler, Daniel Swetz


We report on the 1,000-element transition-edge sensor (TES) x-ray spectrometer implementation of the TOMographic Circuit Analysis Tool (TOMCAT). TOMCAT combines a high spatial resolution scanning electron microscope (SEM) with a highly efficient and pixelated TES spectrometer to reconstruct three-dimensional maps of nanoscale integrated circuits (ICs). A 240-pixel prototype spectrometer was recently used to reconstruct ICs at the 130 nm technology node, but to increase imaging speed to more practical levels, the detector efficiency needs to be improved. For this reason, we are building a spectrometer that will eventually contain 3,000 TES microcalorimeters read out with microwave superconducting quantum interference device (SQUID) multiplexing, and we currently have commissioned a 1,000 TES subarray. This still represents a significant improvement from the 240-pixel system and allows us to begin characterizing the full spectrometer performance. Of the 992 maximimum available readout channels, we have yielded 818 devices, representing the largest number of TES x-ray microcalorimeters simultaneously read out to date. These microcalorimeters have been optimized for pulse speed rather than purely energy resolution, and we measure a FWHM energy resolution of 14 eV at the 8.0 keV Cu Kα line.
IEEE Transactions on Applied Superconductivity


Computed tomography, integrated circuit measurements, scanning electron microscopy, transition-edge sensors


Szypryt, P. , Nakamura, N. , Becker, D. , Bennett, D. , Dagel, A. , Doriese, W. , Fowler, J. , Gard, J. , Harris, J. , Hilton, G. , Imrek, J. , Jimenez, E. , Larson, K. , Levine, Z. , Mates, J. , McArthur, D. , Miaja Avila, L. , Morgan, K. , O'Neil, G. , Ortiz, N. , Pappas, C. , Schmidt, D. , Thompson, K. , Ullom, J. , Vale, L. , Vissers, M. , Walker, C. , Weber, J. , Wessels, A. , Wheeler, J. and Swetz, D. (2023), A tabletop x-ray tomography instrument for nanometer-scale imaging: demonstration of the 1,000-element transition-edge sensor subarray, IEEE Transactions on Applied Superconductivity, [online],, (Accessed April 23, 2024)
Created August 1, 2023, Updated April 20, 2023