Da. Wollman et al., HIGH-RESOLUTION, ENERGY-DISPERSIVE MICROCALORIMETER SPECTROMETER FOR X-RAY-MICROANALYSIS, Journal of Microscopy, 188, 1997, pp. 196-223
We have developed a prototype ii-ray microcalorimeter spectrometer wit
h high energy resolution for use in ii-ray microanalysis. The microcal
orimeter spectrometer system consists of a superconducting transition-
edge sensor X-ray microcalorimeter cooled to an operating temperature
near 100 mK by a compact adiabatic demagnetization refrigerator, a sup
erconducting quantum interference device current amplifier followed by
pulse-shaping amplifiers and pileup rejection circuitry, and a multic
hannel analyser with computer interface for the real-time acquisition
of X-ray spectra. With the spectrometer mounted on a scanning electron
microscope, we have achieved an instrument response energy resolution
of better than 10 eV full width at half-maximum (FWHM) over a broad e
nergy range at real-time output count rates up to 150 s(-1). Careful a
nalysis of digitized X-ray pulses yields an instrument-response energy
resolution of 7.2 +/- 0.4 eV FWHM at 5.89 keV for Mn K alpha(1,2) X-r
ays from a radioactive Fe-55 source, the best reported energy resoluti
on for any energy-dispersive detector.