Characterization and simulation of Avalanche PhotoDiodes for next-generation colliders

This work reports on a novel effort to use Avalanche PhotoDiodes (APDs) to construct an active pixel detector for charged particles in collider experiments. A dual-beam Focused Ion Beam setup was used to characterize the response of the device. Results on the sensitivity of the guard structures separating pixels are compared to a detailed Monte Carlo simulation. These results suggest that, through control of the doping concentration, devices with a much improved fill factor can be achieved. A new technology is proposed that could elevate the fill factor to 100%.