A Layered SAW Device Using Crystal Reflective Gratings

In this paper, a design which combines two-port acoustic wave (SAW) devices and phononic crystals as reflected gratings is demonstrated for the first time. difference time-domain method is used to analyze the of surface acoustic waves encountering the phononic grating. The simulation shows that reflected surface waves result in resonant waves, and this helps to the frequency response of the two-port SAW device. A ZnO/Si SAW device and a square lattice phononic crystal of cylindrical holes on the silicon half space were . The phononic crystal has a band gap of 194-223 MHz surface acoustic waves along the ÃX direction. With the crystal of fifteen-layer cylinders, experimental insertion shows a 7-dB improvement at the 212 MHz central frequency the case without gratings. This newly proposed structure provide a new idea for designs of resonators, filters, or other applications.