Acoustic wave device with multi-layer interdigital transducer electrode having layer of more dense material over layer of less dense material
AssigneeSkyworks Solutions, Inc.
InventorsBenjamin Paul Abbott, Gong Bin Tang, Rei Goto, Keiichi Maki
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Abstract
An acoustic wave device includes a piezoelectric layer and an interdigital transducer electrode disposed over the piezoelectric layer. The interdigital transducer electrode is thicker in a center region of the interdigital transducer electrode than in a gap region of the interdigital transducer electrode to thereby reduce a mass loading of the interdigital transducer electrode in the gap region. The interdigital transducer electrode has a layer of more dense material disposed of a layer of less dense material.
Claims20
An acoustic wave device comprising:
- a piezoelectric layer;
- and
- an interdigital transducer electrode including a first layer disposed over the piezoelectric layer and a second layer disposed over the first layer, the second layer being a top layer of the interdigital transducer electrode and of a more dense material than the first layer, a thickness of the second layer in a gap region of the interdigital transducer electrode being smaller than a thickness of the second layer in a center region of the interdigital transducer electrode to thereby reduce a mass loading of the interdigital transducer electrode in the gap region.
A radio frequency module comprising:
- a package substrate;
- an acoustic wave filter configured to filter a radiofrequency signal, the acoustic wave filter including an acoustic wave resonator that includes a piezoelectric layer and an interdigital transducer electrode including a first layer disposed over the piezoelectric layer and a second layer disposed over the first layer, the second layer being a top layer of the interdigital transducer electrode and of a more dense material than the first layer, a thickness of the second layer in a gap region of the interdigital transducer electrode being smaller than a thickness of the second layer in a center region of the interdigital transducer electrode to thereby reduce a mass loading of the interdigital transducer electrode in the gap region;
- and
- additional circuitry, the acoustic wave filter and additional circuitry disposed on the package substrate.
A wireless communication device comprising:
- an antenna;
- and
- a front end module including an acoustic wave filter configured to filter a radio frequency signal associated with the antenna, the acoustic wave filter including one or more acoustic wave devices that each include a piezoelectric layer and an interdigital transducer electrode including a first layer disposed over the piezoelectric layer and a second layer disposed over the first layer, the second layer being a top layer of the interdigital transducer electrode and of a more dense material than the first layer, a thickness of the second layer in a gap region of the interdigital transducer electrode being smaller than a thickness of the second layer in a center region of the interdigital transducer electrode to thereby reduce a mass loading of the interdigital transducer electrode in the gap region.
Dependencies are inferred from the claim text.