Lateral homogeneity variation in metal plasma immersion ion implantation and deposition

Abstract

Using a cathodic arc, with a shield to reduce the droplet rate, it is possible to obtain homogeneous AlN films across substrates with diameters up to 10 cm by metal plasma immersion ion implantation and deposition (MePIIID). The film thickness varies by less than 5%, as measured by spectroscopic ellipsometry. For a sample with a diameter of 10 cm no major influence of the voltage on the thickness homogeneity was observed. However, for a sample with a diameter of 6 cm and the same deposition conditions the thickness at the edge decreased by more than 33 and 50% for pulse voltages of 5 and 10 kV, respectively. Thus, the geometry of the shield and the sample holder can have a strong influence on the direction of the plasma stream emanating from the cathodic arc. Additionally, the working pressure and plasma composition plays a major role in determining the homogeneity, as was observed using Al and Ti cathodes without background gas or with nitrogen.