DUPLEXER AND METHOD OF MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a duplexer capable of easily adjusting a fractional bandwidth of first and second band pass filters and also achieving miniaturization.SOLUTION: A duplexer 1 has a structure in which a low acoustic velocity film 5 and a piezoelectric film 6 are laminated on a high acoustic velocity film 4. An IDT electrode 7 for constituting a first band pass filter and an IDT electrode 8 for constituting a second band pass filter are formed on one surface of the piezoelectric film 6. A thickness of the piezoelectric film 6 on a portion where the first band pass filter is formed is different from a thickness of the piezoelectric film 6 on a portion where the second band pass filter is formed.SELECTED DRAWING: Figure 1