Nanoimprinted high-frequency surface acoustic wave devices: Generation, characterization and acousto-electric transport

This thesis deals with both the excitation and characterization of high-frequency SAWs, as well as with SAW-induced charge transport by using an electrical excitation method. SAWs are widely used and very important in both research and industry. In piezoelectric materials, they can be excited through the inverse piezoelectric effect by using interdigital transducers (IDTs). Because of the piezoelectricity of the material, a piezoelectric potential wave accompanies the mechanical wave. The unique SAW properties make them suitable not only for signal processing, but also for sensing applications, photonics, and charge transport. The SAW frequency is determined by the periodicity of the IDT electrodes and the acoustic velocity of the material. Almost for all applications, there is a strong demand for higher frequencies, for example to enhance the processing speed or to reach the single-charge manipulation regime.