  It is well known that avalanche photodiodes operated in the Geiger mode above
the breakdown voltage offer a virtually infinite sensitivity and time accuracy
in the picosecond range that can be used for single photon detection. However,
their performance in particle detection remains still unexplored. In this
contribution, we are going to expose the different steps that we have taken in
order to prove the efficiency of Geiger mode avalanche photodiodes in the
aforementioned field. In particular, we will present an array of pixels of
1mmx1mm fabricated with a standard CMOS technology for characterization in a
test beam.
