Articolo in rivista, 2021, ENG, 10.3390/s21092932

Fabrication of small-pixel cdznte sensors and characterization with x-rays

Tsigaridas S.; Zanettini S.; Bettelli M.; Amade N.S.; Calestani D.; Ponchut C.; Zappettini A.

European Synchrotron Radiation Facility (ESRF), 71 Avenue des Martyrs, F-38043 Grenoble, France; Due2lab s.r.l., via Paolo Borsellino 2, 42019 Scandiano, Italy; IMEM-CNR, Istituto Materiali per l'Elettronica e il Magnetismo, Consiglio Nazionale delle Ricerche, Parco Area delle Scienze 37/A, 43124 Parma, Italy;

Over the past few years, sensors made from high-Z compound semiconductors have attracted quite some attention for use in applications which require the direct detection of X-rays in the energy range 30-100 keV. One of the candidate materials with promising properties is cadmium zinc telluride (CdZnTe). In the context of this article, we have developed pixelated sensors from CdZnTe crystals grown by Boron oxide encapsulated vertical Bridgman technique. We demonstrate the successful fabrication of CdZnTe pixel sensors with a fine pitch of 55 µm and thickness of 1 mm and 2 mm. The sensors were bonded on Timepix readout chips to evaluate their response to X-rays provided by conventional sources. Despite the issues related to single-chip fabrication procedure, reasonable uniformity was achieved along with low leakage current values at room temperature. In addition, the sensors show stable performance over time at moderate incoming fluxes, below 10 photons mm s .

Sensors (Basel) 21 , pp. 2932–2946

Keywords

cadmium zinc telluride (CdZnTe), vertical Bridgman, high-Z sensors, pixel detectors, X-ray detectors, Timepix

CNR authors

Bettelli Manuele, Sarzi Amade Nicola, Zanettini Silvia, Zappettini Andrea, Calestani Davide

CNR institutes

IMEM – Istituto dei materiali per l'elettronica ed il magnetismo