Nanometric AlN Thin Films Growth by Non Reactive RF Sputtering
C. Chesman, J.A.S. Moura, I. Guedes
Universidade Federal Do Rio Grande Do Norte, BR
Keywords: nitride semiconductors, nanostructures, RF Sputtering
Abstract:The technological interest on direct wide bandgap semiconductor has grown considerably in recent decades, primarily for their use in optoelectronic and acoustic devices as well as in high power electronics. The aluminum nitride (AlN) and its ternary compounds, have widely been used as a prototype of these new devices. The main technique used to produce nanometric AlN films is the reactive RF-sputtering, with a RF power of hundreds of watts (100 to 300 W). The main drawback of this process is the low rate of reproducibility of the nanometric films obtained. In this work, we report the grow of nanometer AlN films, produced by non reactive RF-sputtering using moderate RF power (~50 W). In this process we use targets of AlN (99.9%) in an argon atmosphere. The thin films are deposited onto glass substrates using a commercial magnetron sputtering (AJA International). These characteristics result in a low deposition rate. Therefore, it takes several hours (1 to 10 hours) for obtaining films with nanometric scale. Preliminary results of Raman spectroscopy show the existence of the AlN phase in all samples deposited, as revealed by the observation of the vibrational mode at 650 cm-1.