Oxide thickness dependence of high-energy-electron-, VUV-, and corona-induced charge in MOS capacitors

Abstract

The radiation‐induced flatband voltage shift of MOS capacitors using dry‐O₂‐grown SiO₂ is shown to vary as the square of oxide thickness for penetrating 1‐MeV electron radiation and linearly with oxide thickness for nonpenetrating 10.2‐eV photon radiation. Corona discharge experiments on unmetallized portions of the same oxidized silicon wafers also show a flatband voltage shift linearly dependent upon oxide thickness. These experiments provide strong evidence to support a simple generation, transport, and trapping model for radiation charging of SiO₂. The results also show that for dry oxides the density of trapped holes near the Si‐SiO₂ interface is indepenent of oxidation time.