Synthesis of metal nitrides by low-energy ion assisted film growth

In this short report the influence of the low-energy ion bombardment of growing films on the structural properties is demonstrated and discussed. The preferred orientation and texture are measured in dependence on the ion energy, angle of incidence and film thickness. The preferred orientation is changed from a {111} alignment of the TiN crystallites to the {100} orientation with increase of ion energy and ion current density. The film formation at ion bombardment under a specifically selected angle results in a totally fixed orientation or biaxial texture of the crystallites. The measurements also show that the {100} biaxial texture is changed to a {111} biaxial texture with increase of the film thickness. The crystalline structure of epitaxial GaN films on c-plane sapphire depends strongly on the ion beam parameter. To obtain high quality films low ion energies are required. Pole figure measurements show that even with unadvantageous growth parameters the GaN films remain epitaxial.