Process for growing a dielectric layer on a silicon-containing surface using a mixture of N2O and O3

摘要

This invention is embodied in an improved process for growing high-quality silicon dioxide layers on silicon by subjecting it to a gaseous mixture of nitrous oxide (N2O) and ozone (O3). The presence of O3 in the oxidizing ambiance greatly enhances the oxidation rate compared to an ambiance in which N2O is the only oxidizing agent. In addition to enhancing the oxidation rate of silicon, it is hypothesized that the presence of O3 interferes with the growth of a thin silicon oxynitride layer near the interface of the silicon dioxide layer and the unreacted silicon surface which makes oxidation in the presence of N2O alone virtually self-limiting. The presence of O3 in the oxidizing ambiance does not impair oxide reliability, as is the case when silicon is oxidized with N2O in the presence of a strong, fluorine-containing oxidizing agent such as NF3 or SF6.