The effects of oxidant pressure on the kinetics of thermal oxidation of (100) and (111) oriented silicon wafers in dry ambients were investigated over the temperature range of 800°–1000°C and the pressure range of 1–20 atm. The parabolic and linear rate constants were found to be proportional to oxygen pressure to the power of 1 and 0.7, respectively. A change in activation energy similar to that observed for pyrogenic steam oxidation occurs around 900°C. Oxide charges in oxides prepared in high pressure dry ambients were characterized and found to be compatible with present technological requirements for VLSI device fabrication, although increases in electron trapping due to neutral traps have been observed.