Radiation hard position-sensitive cryogenic silicon detectors: the Lazaruseffect

The discovery of the so-called Lazarus effect, namely the recovery of the c harge collection efficiency (CCE) of irradiated silicon detectors by means of cryogenic cooling has entailed an increasing interest in the behavior of silicon detectors at cryogenic temperatures. We have measured the CCE of a silicon p-i-n diode detector previously irradiated with an equivalent flue nce of 1 x 10(15) n/cm(2) neutrons of 1 MeV energy. The charge collection e fficiency has been measured at 77 ii;. showing that the low-temperature ope ration considerably decreases the bias current. This is also the case when forward voltage bias is applied, which then becomes a suitable option. In t his condition, the sample shows a charge collection efficiency in excess of 65% at 250 V corresponding to a most probable signal for a minimum ionizin g particle of 21000e(-). (C) 2000 Elsevier Science B.V. All rights reserved .