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SPAD detector

This activity is carried out since 2001 in collaboration with the R & D department of ST Microelec- tronics (STM). The research has the aim to find-out new detectors suitable for astrophysical applications.
SPAD is the acronym of Single Photon Avalanche Diode and means that silicon diodes are used as detectors operating in photon counting regime to detect faint sources. In this context we would have detectors that show typical QE of Silicon (relatively high in the visible band) like CCDs but capable to work as photon counters. To operate this kind of diode in photon counting, an appropriate electronic circuit called "active quenching'' or AQC is required. The AQC turns off the biasing for a dead (hold-off) time, and makes it ready for another event. The dead-time depends on the quality of the SPAD. Typical dead times obtained recently are of the order of tens of nanoseconds and make these devices very attractive also for adapitive opitcs applications.
In the past year we have developed, realized and tested an AQC to drive a single SPAD detector and we continue to utilize this circuit to test the various SPADs produced by STM. During this year more than twenty devices have been characterized.
Furthermore we have started a new project in collaboration with STM and several scientific institutions (INFN, IMM-CNR and the University of Catania) to develop a camera based on a SPAD array which will be used for different scientific and industrial applications. The COLD group will be responsible for and participate in the characterization of the detector, the development of the front-end electronics, the development of the active quenching circuit, and the development of control software. The final product will be tested at the 91-cm telescope of the INAF - Catania Astrophysical Observatory.


next up previous contents index
Next: SPAD ARRAY (SPADA) detector Up: Detectors Previous: CVD Diamonds detectors   Contents   Index
Innocenza Busa' 2005-11-14