Synthesis and characterization of AlN thin films deposited using dc and rf magnetron sputtering

Abstract

We present a comparative study of synthesis and characterization aluminum nitride (AlN) thin films deposited using a direct current (dc) and a radio frequency (rf) magnetron sputtering (MS)process. In both cases transparent and amorphous AlN phases are formed, albeit at quite different partial N2 gas flows. It appears that the formation of amorphous and transparent AlN phase takes place from a transient state of Al target and the deposition rate reduced by about 50-70% as compared to pure Al metal. However, overall deposition rates were found to be higher in the dcMS process. It was found that the formation of transparent AlN phase is very sensitive to N2 flow in the rfMS process but not so much in the dcMS process. Amorphous and transparent AlN thin films grown using the dcMS and rfMS processes were studied using x-ray diffraction and N K-edge x-ray absorption spectroscopy techniques. Obtained results are presented and discussed in this work.