Papers by Author: Donatella Puglisi

Paper TitlePage

Authors: Donatella Puglisi, Gaetano Foti, Giuseppe Bertuccio
Abstract: The achievement of nuclear detectors in Silicon Carbide imposes severe constraints on the electronic quality and thickness of the material due to the relatively high value of the energy required to generate an electron-hole pair (7.8 eV) in this material compared to the value for Si (3.6 eV). In this work, 4H-SiC charged particle detectors were realised using epitaxial layers of n-type doping as active region. The thickness of the epilayer is always below 80 μm with a net doping concentration in the range of 8 x 1013 to 1016 cm-3. These properties allowed the fabrication of Schottky diodes that operate well as radiation detectors. At low doping concentration, the epilayer is totally depleted at quite low reverse bias (≈ 50 V), thereby obtaining the maximum active volume.
Authors: Giuseppe Bertuccio, S. Caccia, Filippo Nava, Gaetano Foti, Donatella Puglisi, Claudio Lanzieri, S. Lavanga, Giuseppe Abbondanza, Danilo Crippa, F. Preti
Abstract: The design and the experimental results of some prototypes of SiC X-ray detectors are presented. The devices have been manufactured on a 2’’ 4H-SiC wafer with 115 m thick undoped high purity epitaxial layer, which constitutes the detection’s active volume. Pad and pixel detectors based on Ni-Schottky junctions have been tested. The residual doping of the epi-layer was found to be extremely low, 3.7 x 1013 cm-3, allowing to achieve the highest detection efficiency and the lower specific capacitance of the detectors. At +22°C and in operating bias condition, the reverse current densities of the detector’s Schottky junctions have been measured to be between J=0.3 pA/cm2 and J=4 pA/cm2; these values are more than two orders of magnitude lower than those of state of the art silicon detectors. With such low leakage currents, the equivalent electronic noise of SiC pixel detectors is as low as 0.5 electrons r.m.s at room temperature, which represents a new state of the art in the scenario of semiconductor radiation detectors.
Showing 1 to 2 of 2 Paper Titles