Abstract
Electrical bias stressing and X irradiation experiments have been carried out on HfO2/SiO2 dielectric stacks. Evidence is found for a negative electric field induced positive charge injection and trapping and radiation induced positive charge trapping. Positive electric fields associated with radiation result in negative charge trapping. Potential-induced cyclic injection/removal of positive charge is also observed. It is suggested that these structures are radiation soft. (c) 2007 American Institute of Physics.