Fluence dependence of IBIC collection efficiency of CMOS transistors

Abstract

IBIC (Ion Beam Induced Charge) imaging of deep structures of semiconductor devices with a focused MeV light ion beam has been shown to offer significant advantages over the established EBIC (Electron Beam Induced Current) technique, because the large range and the small lateral straggling of the ion beam allows direct imaging of buried device structures. The technique is limited by the accumulation of radiation damage that reduces the charge collection efficiency. We report on measurements of the beam fluence dependence on IBIC collection efficiency for proton and alpha particle beams at 2000 keV energy. A HCF4007 CMOS transistor array was used in these measurements. The influence of surface passivation layers on charge collection efficiency and its evolution with ion dose is discussed. ©1998 Elsevier Science B.V.