Dielectric breakdown induced by sodium in MOS structures

Scanning internal photoemission measurements of several MOS structures, which contained mobile sodium ions, displayed nonuniform contact barriers at the SiSingle Bond signSiO2 interface. A direct correspondence was found between the areas at which the contact barrier was a minimum and the point at which subsequent dielectric breakdown occurred. The direct relationship between barrier reduction and breakdown may result from enhanced electronic injection at the areas with a lower contact barrier. © 1973 American Institute of Physics.