Response ability and detection of load position to cyclic stress in LiNbO3thin film with c-axis orientation on polycrystalline Si3N4 substrates

LiNbO3 thin films with c-axis orientation were deposited on polycrystalline Si3N4 substrates by means of RF-magnetron sputtering method. Response abil ity to cyclic stress of the Si3N4 specimen coated by LiNbO3 thin films was evaluated by a 3-point bending fatigue test. The voltage range produced by LiNbO3 thin films increased linearly with the maximum stress during the cyc lic test. The voltage range depended on the frequency of cyclic stress. The position of cyclic compressional load was revealed due to the different ge nerations of voltage signals at a multielectrode placed between the LiNbO3 thin film and Si3N4 substrate.