Picosecond Photoacoustic Metrology of SiO 2 and LiNbO 3 Layer Systems Used for High Frequency Surface-Acoustic-Wave Filters

摘要

Many applications of thin films necessitate detailed information about their thicknesses and sound velocities. Here, we study SiO 2 /LiNbO 3 layer systems by picosecond photoacoustic metrology and measure the sound velocities of the respective layers and the film thickness of SiO 2 , which pose crucial information for the fabrication of surface-acoustic-wave filters for communication technology. Additionally, we utilize the birefringence and the accompanying change in the detection sensitivity of coherent acoustic phonons in the LiNbO 3 layer to infer information about the LiNbO 3 orientation and the layer interface.