Resonant Inc.
TRANSVERSELY-EXCITED FILM BULK ACOUSTIC RESONATOR PACKAGE

Abstract:

Acoustic resonator devices and filters are disclosed. A piezoelectric plate is attached to a substrate, a portion of the piezoelectric plate forming a diaphragm spanning a chip cavity in the substrate. A first conductor pattern is formed on a surface of the piezoelectric plate. The first conductor pattern includes interleaved fingers of an interdigital transducer on the diaphragm, and first contact pads. An interposer has walls on its back surface that are attached to the chip front surface and that surround the diaphragm. An interposer cover layer spans the walls creating an enclosed interposer cavity over the diaphragm. A second conductor pattern formed on the walls and cover layer includes second contact pads on the interposer back surface. Electrical connections between the second contact pads and connection points on the chip electrically connect the first contact pads to respective ones of the second contact pads.