Time Dependent Dielectric Breakdown Measurements on RPECVD and Thermal Oxides

Abstract

Time dependent dielectric breakdown (TDDB) measurements have been made on a 96 Å oxide deposited by remote plasma enhanced chemical vapor deposition (RPECVD) upon a 300°C Si(100) device grade substrate. The oxide was used to form an array of square capacitors. The oxide was then subjected to electron injection from the substrate at 0.1 A/cm2 constant stress current. The charge‐to‐breakdown (QBD) was measured and found to be . A similarly fabricated 92 Å thermal oxide capacitor array showed a QBD value of . Analysis of the forcing voltage during stress showed the RPECVD oxide to have an initial trap density of , compared to for the thermal oxide. In both cases, at 0.1 A/cm2, the stress voltage across the oxide rose linearly with time. Trap generation rates of and were measured for the RPECVD and thermal oxides, respectively. The TDDB data were analyzed to find breakdown occurring in localized areas of containing filled electron traps.