The detection of optical photons with high sensitivity is required in a vast range of applications (fluorescence, scintillation, Cherenkov photons,...).
The classical photomultiplier tubes have been mostly replaced by solid state avalanche diodes and silicon photomultipliers. The latter only produce small signals so that sensitive, often fast, amplifiers are required. The readout ASICs (which we also develop in our group) consume significant power and are an additional component, complicating system design.
An alternative approach uses Avalanche diodes integrated into a CMOS technology, so that detection and readout can be combined on a single chip. After gain ing experience with some test chips, we have submitted an engineering run with several very different readout architectures to fit different needs. Some results from the test chips will be presented and the various
new architectures briefly described.
