Highly textured (100)-oriented AlN thin films using thermal atomic layer deposition and their electrical properties

Aluminum nitride (AlN) thin films are deposited on p-type silicon wafers using atomic layer deposition (ALD) techniques. Tris(dimethylamido) aluminum (TDMAA) and ammonia (NH3) are used as aluminum and nitrogen sources, respectively, and 500 cycles of aluminum and ammonia precursors are used to achieve about 80-nm-thick AlN film. The X-ray diffractogram showed highly textured (100) AlN thin film. Atomic force microscopic images showed smooth films with average and RMS roughnesses ~ 0.30 ± 0.05 nm and 0.39 ± 0.05 nm, respectively. The current–voltage (I–V), resistivity, and capacitance–voltage (C–V) measurements substantiate that deposited AlN films are moderately resistive together with large bandgap ~ 5.8 eV. Thus, using TDMAA as Al precursor, high-quality thin films can be realized using thermal ALD, suitable for high-power electronic and piezoelectronic applications.