We review the knowledge and understanding of proton and electron irradiatio
n-induced defects in Si, GaAs and GaInP. We describe their nature, evaluate
their introduction rates, give the electronic characteristics of the defec
ts which play the role of recombination centers and of those which play the
role of compensating centers. We then briefly describe the techniques whic
h allow to determine these characteristics and to differentiate recombinati
on centers and compensating centers among all the created defects. Finally,
we develop and illustrate the role these specific defects play on the curr
ent generated by a solar cell. (C) 2001 Elsevier Science B.V. All rights re
served.