OXYGEN REDISTRIBUTION DURING LOW-ENERGY OXYGEN IMPLANTATION

The implantation temperature dependence of the oxygen depth profile, microstructure, radiation damage and Si-O bonding was examined in Si implanted with low-energy (25 keV) oxygen. The oxygen depth profile varied with implantation temperature: Gaussian-like shape at 280 degrees C, triangular shape at 590 degrees C, and again a Gaussian-like shape at 740 degrees C. Si-O bonding became tighter, and Si crystal structure was maintained more easily with increasing implantation temperature. Crystal damage near the surface became small for implantation at 740 degrees C. These results suggest that marked oxygen migration and redistribution during ion implantation, which are determined by the oxygen diffusivity and the radiation-damage depth-profile, are the essential phenomena controlling the low-energy SIMOX process.