SURFACE ACOUSTIC WAVE RESONATOR AND SURFACE ACOUSTIC WAVE FILTER DEVICE

摘要

In a surface acoustic wave resonator, a first IDT electrode defining a first IDT and a second IDT electrode defining a second IDT are located on a first principal surface of a piezoelectric substrate. A direction of an electric field applied to the first IDT electrode and a direction of an electric field applied to the second IDT electrode are opposite to each other with respect to a direction of a projected axis resulting from projecting a c-axis of the piezoelectric substrate to the first principal surface of the piezoelectric substrate.

主权项

1. A surface acoustic wave resonator comprising:
a first terminal; a second terminal; first and second IDTs connected between the first terminal and the second terminal; a piezoelectric substrate including a first principal surface and a second principal surface opposed to the first principal surface, and having a c-axis of which direction is inclined relative to the first principal surface and the second principal surface; a first IDT electrode located on the first principal surface of the piezoelectric substrate to define the first IDT, the first IDT electrode including first and second comb-shaped electrodes; and a second IDT electrode located on the first principal surface of the piezoelectric substrate to define the second IDT, the second IDT electrode including third and fourth comb-shaped electrodes; wherein when looking at the first principal surface of the piezoelectric substrate in a plan view, a direction of an electric field applied to the first IDT and a direction of an electric field applied to the second IDT are opposite to each other with respect to a direction parallel to a projected c-axis resulting from projecting the c-axis to the first principal surface of the piezoelectric substrate.