Energy Spectroscopy for Low-energy Photons Using Diamond Detector Combined with Micro-CMOS Preamplifier

To measure soft X-ray energy spectra at room temperature using diamond, we connected a 300-mu m-thick single-crystal CVD diamond radiation detector with excellent charge carrier transport properties to a micro-preamplifier fabricated using CMOS technology via phi 97 gm electrodes. We attempted to measure the photon energy spectrum from a few keV to 60 keV at room temperature by reducing the leakage current and the total input capacitance to the preamplifier. The energy resolution for 5.9 keV X-rays from Fe-55 was Delta E = (484 +/- 10) eV (FWHM).