Isotope Labeling Studies of the Oxidation of Silicon at 1000° and 1300°C

Oxygen‐18 profiles in thermal oxides grown on silicon at 1000° and 1300°C in sequential oxidation steps in the parabolic oxidation regime indicate a change in the dominant oxygen transport process. At 1000°C, oxygen‐18 pile‐up at the surface and at the oxide/silicon interface is consistent with a large flux of oxygen via molecular oxygen permeation and very slow diffusion of lattice oxygen ions . At 1300°C, the oxygen‐18 concentration is uniformly high across the oxide, which suggests a much larger lattice oxygen diffusivity and a total flux due to lattice oxygen diffusion which contributes significantly to the supply of oxygen to the growth interface.