It was recalled that N implantation into Si led to a reduction in the SiO2 thickness of implanted wafers. An investigation was made here of the effect of the implantation energy upon oxidation kinetics in N-implanted Si. The N was implanted into Si wafers using low (3keV) and medium (25, 80 or 150keV) energies, and oxidation was performed at 800 to 900C for various times. The experiments showed that the decrease in oxide thickness was smaller when N was implanted closer to the Si surface. This was attributed to N out-diffusion during the ramping and initial oxidation steps, which was more effective when N was placed closer to the surface. Additional experiments, using various ramping times, supported this explanation. An additional study was performed of the growth of extended defects under various implantation conditions. This permitted the estimation of an energy-dose window within which it was possible to observe very small oxide thicknesses (2.5 to 4nm) without extended defect formation.

Oxidation of Nitrogen-Implanted Silicon - Energy Dependence of Oxide Growth and Defect Characterization of the Silicon Substrate. D.Skarlatos, C.Tsamis, D.Tsoukalas: Journal of Applied Physics, 2003, 93[3], 1832-8