Hydrogen Annealed Nitride/Oxide Dielectric Structures for Radiation Hardness

In this paper we present a study of the influence of processing on low temperature (77°K) radiation effects in nitride/oxide dielectric structures used as an active gate insulator of an MIS device. We have shown that flatband shifts of less than -1.5 volts are obtained following 106 Rad: Si Co60 exposure performed at 77°K on 750Å nitride structures (as long as the oxide were less than 100Å). We have also detected a low temperature hysteresis effect caused by trapping. This hysteresis is removed by hydrogen anneals of the nitride after the last high temperature processing step seen by the uncovered insulator.