title: Microcalorimeter-type energy dispersive X-ray spectrometer for a transmission electron microscope.
abstract: A new energy dispersive X-ray spectrometer (EDS) with a microcalorimeter detector equipped with a transmission electron microscope (TEM) has been developed for high- accuracy compositional analysis in the nanoscale. A superconducting transition-edge-sensor-type microcalorimeter is applied as the detector. A cryogen-free cooling system, which consists of a mechanical and a dilution refrigerator, is selected to achieve long-term temperature stability. In order to mount these detector and refrigerators on a TEM, the cooling system is specially designed such that these two refrigerators are separated. Also, the detector position and arrangement are carefully designed to avoid adverse affects between the superconductor detector and the TEM lens system. Using the developed EDS system, at present, an energy resolution of 21.92 eV full-width-at-half maximum has been achieved at the Cr K alpha line. This value is about seven times better than that of the current typical commercial Si(Li) detector, which is usually around 140 eV. The developed microcalorimeter EDS system can measure a wide energy range, 1-20 keV, at one time with this high energy resolution that can resolve peaks from most of the elements. Although several further developments will be needed to enable practical use, highly accurate compositional analysis with high energy resolution will be realized by this microcalorimeter EDS system.
authors.affiliation: Advanced Nano-Characterization Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. HARA.Toru@nims.go.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Hara
authors.forename: Keiichi
authors.initials: K
authors.lastname: Tanaka
authors.forename: Keisuke
authors.initials: K
authors.lastname: Maehata
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Mitsuda
authors.forename: Noriko Y
authors.initials: NY
authors.lastname: Yamasaki
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Ohsaki
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Watanabe
authors.forename: Xiuzhen
authors.initials: X
authors.lastname: Yu
authors.forename: Takuji
authors.initials: T
authors.lastname: Ito
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yamanaka