Measured radiation effects in MOS capacitors with a proposed new model

Abstract

Flat‐band shift measurements were made on p‐type MOS devices irradiated with electrons at various gate bias voltages. A reproducible curve of flat‐band shift versus gate bias was obtained that could not be readily accounted for with existing models. Data were taken over a wide range of negative and positive gate bias voltages. The model assumes that traps obey Fermi‐Dirac statistics, subject to interface boundary constraints. A linearized quasi‐Fermi level is assumed in the oxide. The resulting distribution of charged traps yields a self‐consistent energy band structure throughout the entire device.