Ultra-thin gate oxide grown on nitrogen implanted silicon

Ultra-thin gate oxide was grown on nitrogen implanted silicon substrates. F or nitrogen implantation, the energy was fixed at 25 keV but the dose was s plit into 5.0 x10(13)/cm(2) and 1.0 x10(14) /cm(2). There were control wafe rs which were not implanted by nitrogen. The grown gate oxide thicknesses w ere 20 Angstrom and 30 Angstrom. The oxidation time to grow 30 Angstrom was increased by 20 % and 50 % for the implanted wafers of 5.0x10(13)/cm(2) an d 1.0x10(14)/cm(2) doses, respectively, when was compared with control wafe rs. The across-wafer and wafer-to-wafer uniformity of the grown oxides was within 2.5 %. The leakage current of gate oxide grown on implanted substrat e was the same level as that of the control wafer. which was about 1.0x10(- 5) A/cm(2) at V-G = 5 V when the oxide thickness was 30 Angstrom.