Highly textured AlN film synthesized on a graphene-like undercoating

Piezoelectric properties of polycrystalline AlN films are strongly dependent on the texture of the material. For a number of applications, such as microelectromechanical systems (MEMS) and acoustic resonators, it is important to have a well-defined (0 0 2) orientation of the crystallites. Using an original method of selective deposition of graphene-like films (GLFs) followed by a simple, safe and efficient chemical vapor deposition (CVD) of AlN, we clearly demonstrate that the GLF sublayer does enhance the texture quality of AlN columnar structures. The improved crystal orientation along the (0 0 2) direction for AlN film grown on GLFs is locally visualized using a scanning electron microscope (SEM) and quantitatively reinforced using Raman spectroscopy.