Quantifying the effect of plasma source ion implantation (PSII) in steel samples near edges
Plasma source ion implantation was used to implant steel samples with nitrogen at energies of 20 keV and typical doses of2x10^16 ions/cm^2. Ion beam analytical techniques were then used to determine the depth profit of the implanted ions at various points between the center and the edge of the sample. The effect of pulse repetition rate was investigated; because it was assumed that an increase in the temperature by increasing the pulse frequency, nitrogen ions penetrate deeper into a sample. Rutherford backscattering spectrometry revealed that nitrogen ions were distributed to a depth of greater than at least 450 nm. For greater sensitivity the nuclear reaction ^14N(d,α_o)^12 C was used and the thickness of the iron nitride was found to be about 1.2 micrometers. The SIMNRA program was used to simulate the experimental spectra. The results are compared to simulated implantation profiles obtained with the monte-carlo code SRIM 2000. The nitrogen implantation varied across the sample.