New silicon drift detectors and CMOS readout electronics for X-ray spectroscopy from room temperature to cryogenic operations

In this work we present new developments of Silicon Drift Detectors (SDDs) and low noise CMOS readout electronics for a possible use in different X-ray spectroscopy applications, from nuclear physics experiments, to detection systems at synchrotron light sources, to XRF (X-Ray Fluorescence) instrumentation. The detectors can be operated in different working conditions, from room temperature, avoiding a complex cooling apparatus, to cryogenic temperatures, as foreseen in nuclear physics experiments. In particular, SDD detectors developed by our collaboration and manufactured by Fondazione Bruno Kessler (FBK), will be used in INFN experiments SIDDHARTA and ARDESIA. Recently FBK has improved its technology in terms of minimization of the leakage current. This improvement allows to obtain relevant X-ray spectroscopy performance with small area SDDs operated close or even at room temperature. This feature well copes with the excellent noise performances of CUBE preamplifier at short shaping times, where the noise contribution of the leakage current has a lower impact. For instance, at +21 °C, with a small area SDD (10mm2) an energy resolution of 135.5 eV has been measured at the Mn-Kα line with 0.375 µs shaping time. This kind of results opens the perspective to high resolution X-ray spectroscopy with SDDs with very high count rates at room temperature.