CHARGE-PUMPING STUDY OF RADIATION-INDUCED DEFECTS AT SI-SIO2 INTERFACE

We have studied electrical defects of [100] Si-SiO2 interface created by gamma rays (Co-60) in submicrometer MOS transistors. By means of th ree-level charge pumping, the energy distribution of interface-trap pa rameters (emission times, cross sections, state density) has been dete rmined in most of the silicon bandgap after different irradiations. We have shown the possibility of characterizing, using standard and thre e-level charge pumping, the oxide traps near the interface (border tra ps) induced by ionizing radiations. Their behaviour in emission regime is here investigated in terms of tunneling mechanism. We propose a ne w method, based on the three-level charge pumping technique, to determ ine the energy distribution of border traps.