Aluminium nitride layers investigated by slow positrons

The structure and uniformity of aluminium nitride (AlN) layers produced by the sputter-ion plating coating technique has been assessed with the positron beam apparatus, Tacitus. A positron stopping profile accounting for different densities was applied to layered structures of AlN/Al and TiN/AlN. Values for the Doppler line-height parameter are attributed to the variation of the coating processes. The thicknesses of the layers were determined by applying the diffusion model.