Radiation response of nanometric HfSiON/SiO2 gate stacks

Abstract

The x-ray irradiation sensitivity of hafnium silicon oxynitride/silicon oxide dielectric stacks deposited on Si has been measured. Clear evidence for trapped negative charge buildup is found for samples biased positively during irradiation and also for negative bias with or without radiation. A two phase buildup of trapped negative charge is observed in the case of irradiation in the presence of positive bias suggestive of different rates of electron trapping in the two layers.