Damage induced in 100%25 internal carrier collection efficiencysilicon photodiodes by 10-60 keV ion irradiation

We measure the change in the response of 100% internal carrier collection efficiency silicon photodiodes having 60 A SiO)2 ) passivation layers due to the damage induced by bombardment with 10-60 keV ions of H, He, N, Ne, and Ar. We find an initially exponential decrease in responsivity with increasing ion fluence {Phi} and use this to define a damage constant beta. The correlation of beta with the nuclear stopping power of the incident ion instead of with the total energy lost to nuclear stopping indicates that damage in a channel lying within the n-type silicon near the Si-SiO)2) interface dominates the radiation-induced change in the photodiode response. We use a fluid model of electron transport in the channel to derive a universal curve to describe the damage as a function of ion fluence and to show that the damage constant beta is proportional to the damage cross section. Over the energy range of this study, damage cross sections of N( ), Ne( ), and Ar( ) are 10-100 times that of He( ), and ~1000 times that of H