Ultrathin 600°C wet thermal silicon dioxide

Abstract

This paper describes the electrical quality of gate oxides grown at 600°C in a wet oxygen environment. The oxides were grown by carrying out the pyrogenic reaction of H2 and O2 at 750°C while keeping the temperature in the sample region at 600°C. Using this approach SiO2 films with thicknesses ranging from 25 to 45 angstrom have been grown. They exhibit leakage current densities comparable to high-temperature thermal oxide films of the same thickness grown in dry oxygen at higher temperatures. Breakdown fields were found to be around 12 MV/cm independent of substrate orientation. Interface trap densities were determined to be in the 1010 cm-2 eV-1 range. Growth rates of 5 angstrom/h were measured for (100) oriented substrates and 6 angstrom/h for (111) surfaces.