A Transition Edge Sensor Microcalorimeter System for the Energy Dispersive Spectroscopy Performed on a Scanning-Transmission Electron Microscope

We are conducting the development of a transition edge sensor (TES) microcalorimeter system for energy-dispersive X-ray spectroscopy (EDS), performed using a scanning-transmission electron microscope (STEM). The operating temperature of the TES microcalorimeter was maintained using a compact dry ³He-⁴He dilution refrigerator. This was pre-cooled by a remote helium cooling loop system and a Gifford-McMahon cooler. These conditions allowed for high-resolution STEM imaging to be achieved. A single-pixel TES microcalorimeter with a polycapillary optic was selected to demonstrate the analytical operation of the EDS system in the STEM. For a Ti-It-Pt sample, an X-ray energy resolution of 8.6 eV full-width at half maximum (FWHM) was obtained at Ir M_{α 1}, Pt M_{α 1}, and Ir M_β. Using an electron device sample, element distribution maps of Si, Ti, and W were obtained using a Si K_{α 1} X-ray energy resolution of 9.7 eV FWHM.