An IDT electrode 3, and an input electrode section 5 and an output electrode section 6 each connecting with the IDT electrode 3 are formed in a filter region on one main surface of a piezoelectric substrate 2, and a semiconductor layer 22 is formed on the other main surface opposite to the one main surface of the piezoelectric substrate 2. The semiconductor layer 22 makes it possible to prevent pyroelectric destruction in the device manufacturing process as well as to prevent out-of-band attenuation characteristics from being degraded.