Microstructure and mechanical properties of stress-tailored piezoelectric AlN thin films for electro-acoustic devices

摘要: Abstract Nanoindentation measurements along with atomic force microscopy, X-ray diffraction, and residual stress analyses on the basis of Raman have been performed to characterize stress-tailored AlN thin films grown using reactive RF magnetron sputtering. The intrinsic gradient caused by growing in-plane grain size film thickness was minimized increasing N 2 concentration in Ar/N gas mixture during growth process. increase did not degrade device-relevant material properties such as crystallographic orientation, surface morphology, piezoelectric response, or indentation modulus. Due comparable for all investigated samples it concluded that mainly crystallites contribute mechanical modulus hardness, while boundaries had only a minor influence. Therefore, tailoring films, device performance, fabrication yield, design flexibility electro-acoustic devices can be greatly improved.