All-Carbon Devices

Silicon, germanium and cadmium have been considered for many years the elective semiconductor detector in ionizing radiation detection physics. The Achilles’ heel of such semiconductors, however, is in their low tolerance to intense radiation damages, in their stability in harsh conditions and in their relatively high noise at room temperature. On the contrary, diamond based detectors are considered today as one of the best radiation-tolerant devices, low noise at room temperature and chemically stable under extreme conditions, which is of paramount interest i.e. for space applications. Nevertheless, also diamond detectors suffer a degradation in terms of their detectivity if operated under very high radiation fluences as demonstrated by the RD42 group. To overcome such a problem several groups hypothesized and implemented diamond detectors with 3D structures of conductive contacts embedded right in the crystal bulk in analogy with what was proposed for silicon and GaAs detectors. For what concerns diamond, we investigated the feasibility of millimeter long buried contacts and shorter ones (below half millimeter) which can be realized by means of pulsed-laser treatments.