| abstract |
To improve the Q value of an elastic wave element in an elastic wave element of a type in which a piezoelectric material substrate is directly bonded to a supporting substrate made of polycrystalline ceramic. An elastic wave element (10) is a piezoelectric material substrate (1A) and an intermediate layer (2) provided on the piezoelectric material substrate (1A), and one or more kinds selected from the group consisting of silicon oxide, aluminum nitride and sialon. An intermediate layer 2 made of a material, and a bonding layer 3 provided on the intermediate layer 2 and selected from the group consisting of tantalum pentoxide, niobium pentoxide, titanium oxide, mullite, alumina, high-resistance silicon and hafnium oxide A bonding layer 3 made of one or more materials, a supporting substrate 5 made of polycrystalline ceramic and directly bonded to the bonding layer 3, and an electrode 9 provided on a piezoelectric material substrate 1A are provided. |