(1011) preferential orientation of polycrystalline AlN grown on SiO2/Si wafers by reactive sputter magnetron technique

Aluminum nitride (AlN) is a ceramic compound that could be used as a processing material for semiconductor industry. However, the AlN crystalline structure plays a crucial role in its performance. In this paper, polycrystalline AlN films have been grown onto Si(1 1 1) and Si(1 0 0) (with an oxide native coverage of SiO2) wafers by RSM (reactive sputter magnetron) technique using a small (5 L) reactor. The development of polycrystalline AlN films with a good texture along (1011) planes, i.e., semi-polar structure, was shown. Analyses were done using X-ray diffraction in the Bragg-Brentano mode and in the GIXRD (grazing incidence X-ray diffraction) one, and the texture was determined through pole figures. The structure and composition of these films were also studied by TEM and EDS techniques. Nevertheless, the mapping of the magnetic field between the magnetron and the substrate has shown a lack of symmetry at the region near the substrate. This lack of symmetry can be attributable to the small dimensions of the chamber, and the present paper suggests that this phenomenon is the responsible for the unusual (1011) texture developed.