Preparation of highly oriented aluminum nitride thin films on molybdenum bottom electrodes using metal interlayers

We have investigated the influence of metal interlayers on the crystallinity and crystal orientation of aluminum nitride (AlN) thin films prepared on molybdenum (Mo) bottom electrodes. The interlayres were prepared between the Mo bottom electrodes and silicon substrates. Although the sputtering conditions of AlN films and Mo electrodes were the same, the Au/Ti interlayer drastically increased the XRD intensity of the (0002) AlN and (110) Mo planes, and decreased the full width at half maximum (FWHM) of the rocking curves of the (0002) AlN peaks from 9.22◦ to 3.02◦. The Au/Ti interlayers were effective for the improvement in the crystallinity and crystal orientation of AlN films deposited on Mo bottom electrodes. Furthermore, we clarified that the crystallinity and orientation of AlN films and Mo electrodes strongly depend on those of the Au interlayers, and the Au interlayers influence the morphologies of the Mo electrodes. C 2005 Springer Science + Business Media, Inc