Temperature and dose dependences of nitrogen implantation into aluminium

It has been established that nitrogen implantation into metals can alter their surface properties such as friction, wear, corrosion, etc. Recent studies have shown that nitrogen implantation into aluminium leads to the formation of aluminium nitride which has interesting tribological, electronic and optical properties. For a given implantation energy, the characteristics of the nitrogen profile, e.g. thickness, shape and concentration, depend strongly on the experimental conditions during the implantation. In order to study the influence of the implantation parameters, aluminium samples have been bombarded with N of 100 keV to different doses ((1-20) × 10 N/cm), at several temperatures (25-300° C). Distributions of the implanted species were investigated by nuclear reaction analysis (NRA) and by Rutherford backscattering spectroscopy (RBS). The chemical bonds of aluminium in the matrix were studied by using low-energy electron-induced X-ray spectroscopy (LEEIXS). It is shown that aluminium nitride is formed and that the nitrogen distribution presents a surface peak when the implantation temperature is higher than 200° C.