Effect of RF power on AlN film crystallinity in low pressure range using Ar-20%N2 gases by magnetic mirror-type magnetron cathode

Abstract

Abstract Effect of radio frequency (RF) power on aluminum nitride (AlN) film crystallinity has been studied under low gas pressure of ≥ 0.1 Pa and low RF power of ≥ 3 W with Ar-20%N2 gas by a proposed balanced magnetron cathode with a high plasma production efficiency. The gas pressure and the RF power dependences of AlN film crystallinity show that the c-axis oriented AlN films can be obtained only at 50 W and 100 W in 0.1 Pa. The AlN film crystallinity was not promoted in the low RF power range of <50 W. An Ar-rich sputtering condition at 0.1 Pa induced the Al–Al bonds in the deposited films in a high RF power range of ≥ 15 W. The control of the total flux balance between Al and nitrogen atoms at the substrate surface is important to design the optimum sputtering condition at 0.1 Pa.