XPS study of iron surface layers implanted with both titanium and nitrogen

Iron plates were implanted at room temperature to doses of 1x1017 ions/cm2 with 150 keV Ti ions and subsequently with 20, 45 or 75 keV N ions at the same dose. Chemical bonding states and depth profiles of Ti, N and C in the implanted layer were measured by XPS. Changes in the crystal structure of implanted layers were investigated by X-ray diffraction spectrometry. Ti which was present in the metal state after Ti implantation was changed to Ti nitride inside the N distributions and further a part of the Fe-Ti solid solution disappeared. Implanted N formed Ti or Fe nitrides. C which was incorporated from vacuum at the time of Ti implantation showed no change of chemical bonding states after N ion implantation and was present in the state of Fe-carbide. (orig.)