Patent ID: 9647633
Date: 2017-05-09
CPC Classifications: H01L,H03H

Claim:
1. An acoustic wave element comprising: a piezoelectric substrate, an IDT comprising a first comb-shaped electrode and a second comb-shaped electrode which are located on an upper surface of the piezoelectric substrate, and a single capacitance element which is located on the upper surface of the piezoelectric substrate and is electrically connected to the IDT, wherein the first comb-shaped electrode comprises the second comb-shaped electrode comprises in the first comb-shaped electrode and the second comb-shaped electrode, the plurality of first electrode fingers and the plurality of second electrode fingers mesh with each other, the first electrode fingers have tips facing the second comb-shaped electrode across first gaps in their extending direction, the second electrode fingers have tips facing the first comb-shaped electrode across second gaps in their extending direction, the capacitance element comprises the direction from the first counter electrode through the third gap toward the second counter electrode is a reverse direction from the direction from the first comb-shaped electrode through the first gaps toward the second comb-shaped electrode and from the direction from the first comb-shaped electrode through the second gaps toward the second comb-shaped electrode, with respect to a crystal orientation, and a length D and width L of the third gap satisfy the following formula (A) where the total number of the first gaps and the second gaps is n where n≧2, and lengths and widths of the i-th first gap and second gap among the first gaps and the second gaps which are counted in order from one end of the IDT are di and wi where 1≧i≧n: