Investigating radiation effects on high-speed optoelectronic devices by combining time-resolved laser and ion microbeam studies

High-speed optoelectronic devices are increasingly used for a wide range of functions in space based satellites and research with typical applications ranging from intra-satellite fiber optic communication through to specialized detectors for astronomical observation. In this paper, we illustrate some of the more important effects in high-speed photodetectors and illustrate by way of example, methods in which time-resolved methods of analyses with the MeV ion (Transient Ion Beam Induced Current) and pulsed picosecond laser microbeams can be used to further understand the role of high-injection effects on SET (Single Event Transient) spatio-temporal evolution. Two complimentary photodetector configurations will be addressed including Si p-i-n and GaAs Metal Schottky Metal (MSM) photodetectors. Despite the large differences in the structure of their electric fields, both systems were characterized by SET's which displayed large space-charge dependencies as predicted by simulation. A general qualitative description is given.