PURPOSE: To obtain firm coupling between a diamond layer and comb shaped screen type electrodes by using an AlN, an Si3N4, an SiO2, a ZnO, an Al2O3, or the like as the material of an intermediate layer.
CONSTITUTION: In a surface acoustic wave element having diamond or a diamond layer 2, Al or an electrode layer 4 essentially consisting of Al, and a piezoelectric body layer 5 in this order, an intermediate layer 3 consisting of materials selected from an AlN, an Si3N4, an SiO2, a ZnO, and an Al2O3 is interposed between diamond or the diamond layer 2 and the electrode layer 4. Various diamond or diamond layers 2 can be used to produce the surface acoustic wave element in this case, but it is preferable that the diamond layer 2 prepared by the ionizing vapor-deposition method which is easy to form and has a good characteristic out of compounds is used because single crystal films and natural materials are expensive and have problems on working. This diamond layer 2 has a sufficiently high film strength and is easy to handle and has sufficient adhesive strength with a substrate.
SATO KATSUO
HATSUDA RANKO
SHIBAHARA MASANORI