Thick (∼1.3 &mgr;m) oxide films were grown by room‐temperature oxidation of silicon after low‐energy copper‐ion implantation. The structural properties of the silicon dioxide layer and the implanted silicon were characterized by Rutherford backscattering spectrometry and transmission‐electron microscopy. During the room temperature oxidation a portion of the implanted copper resided on the surface and a portion moved with the advancing Si/SiO2interface. This study revealed that the oxide growth rate was dependent on the amount of Cu present at the moving interface. The surface copper is essential for the dissociation of oxygen at the surface, and it is this oxygen that participates in the oxidation process. The resulting oxide formed was approximately stoichiometric silicon dioxide. ©1996 American Institute of Physics.