Development of InSb cryogenic detector for ultra high-resolution energy spectroscopy

High-resolution X-ray spectroscopy is required in research and application areas such as neutrino mass measurement, X-ray astronomy, semiconductor device technology and material analysis. The conventional detectors such as Si or Ge do not have enough energy resolution to meet the requirements from the various fields. Compound semiconductor with small band gap can be possible candidate detector to get the ultra-high resolution. InSb Schottky diode is being developed as the radiation detector because of their low band gap energy. The dependency of detector performance on electrode size, etching method, and operating temperature was studied. The polished wafers were cut into with size of 10times10 mm², and the wafer surfaces were cleaned and etched. Gold electrode was deposited on one side of the etched wafer and In was deposited on the opposite side of the wafer. The I-V curve of each diode was measured and the results were compared to optimize the fabrication process of InSb Schottky detector.