Abstract
Films of thermal SiO2 in the thickness range 30−300 Å were stressed at fields approaching breakdown. Intrinsic breakdown was observed to be preceded by generation of a very high density of electron traps. These traps must be energetically located at least 4 eV below the SiO2 conduction band and may be assocated with broaken Si‐O bonds. The ultimate breakdown strength of ultrathin films was found to be (2.8±0.4) ×107 V/cm. The present work suggests a new mechanism to explain intrinsic breakdown in films of thermal SiO2.