PURPOSE: To obtain the surface acoustic wave convolver of high efficiency by providing plural electrode strings, which are respectively connected to metal strip strings, and a diode string to be composed of an output electrode.

CONSTITUTION: An aluminiumnitride AlN layer 2, a dielectric layer 3 and an n+ cilicone layer 6 are formed on a sapphire substrate 1 and an (n)-type epitaxial silicon layer 5 and a thermally oxidized layer 4 are formed on the silicon layer 6. For a tandem-shaped ground electrode 11 to be formed on the AlN 2 layer, a metal strip string 8 exists between the respective comb shaped electrodes and a cross area is formed. Then, the electrode goes to be the propagation route of a surface acoustic wave SAW. The SAW to be inputted from an input transducer is propagated with being faced and the potential of the SAW is guided to a shot key diode 9 by the strip string 8. The diode 9 is operated as a varactor diode and a convolution signal appears in an output electrode 11.