SURFACE ANALYTICAL INVESTIGATIONS OF AL AND (TI, AL) NITRIDES FORMED BY ION-IMPLANTATION AND THEIR CORROSION PROPERTIES

Nitrides of Ti, Al and TiAl(x) alloys were prepared by low energy ion implantation (3 keV N2+). The layer thickness was approximately 10 nm. The nitride layers were characterized using XPS, UPS and a Kelvin pro be. The insulating properties known for bulk AIN were found also for t he prepared AIN(impl) layers. The work functions for the alloys and th e nitrides and their variation with the ion dose were determined. Peak parameters for the XP spectra deconvolution were established. Despite their thinness, the layers showed anodic stability in 0.5 M H2SO4 up to 1.3 V (SHE) for (TiAl)N(impl) and even up to 1.8 V (SHE) for AIN(im pl). Above these potentials, the nitrides were oxidized to metal oxide s.