BAW RESONATOR ARRANGEMENT WITH RESONATORS HAVING DIFFERENT RESONANCE FREQUENCIES AND MANUFACTURING METHOD
In at least one embodiment, the electric component comprises a first BAW-resonator ( 1 ), a second BAW-resonator ( 2 ) electrically connected to the first BAW-resonator and a carrier substrate ( 3 ) with a top side ( 30 ) on which the BAW-resonators are arranged. The first and the second BAW-resonator each comprise a bottom electrode ( 11,21 ) and a top electrode ( 12,22 ). The bottom electrodes are in each case located between the carrier substrate and the respective top electrode. A first piezoelectric layer ( 13 ) is arranged between the top electrode and the bottom electrode of the first BAW-resonator and laterally protrudes from the first BAW-resonator. The second BAW-resonator is mounted on the first piezoelectric layer in a region laterally next to the first BAW-resonator and comprises a second piezoelectric layer ( 23 ) between its top electrode and its bottom electrode. The two piezoelectric layers may have different thickness to realize resonators with different resonance frequencies on the same die.
1 . An electric component comprising:
a first BAW-resonator;
a second BAW-resonator electrically connected to the first BAW-resonator; and
a carrier substrate with a top side on which the BAW-resonators are arranged, wherein:
the first and the second BAW-resonator each comprise a bottom electrode and a top electrode,
the bottom electrodes are in each case located between the carrier substrate and the respective top electrode,
a first piezoelectric layer is arranged between the top electrode and the bottom electrode of the first BAW-resonator and laterally extends from the first BAW-resonator, and
the second BAW-resonator is mounted on the first piezoelectric layer in a region laterally next to the first BAW-resonator and comprises a second piezoelectric layer between the top electrode of the second BAW-resonator and the bottom electrode of the second BAW-resonator.
2 . The electric component according to claim 1 , wherein the first piezoelectric layer and the second piezoelectric layer have different thicknesses.
3 . The electric component according to claim 1 , wherein a dummy electrode is located between the second BAW-resonator and the carrier substrate.
4 . The electric component according to claim 3 , wherein the bottom electrode of the first BAW-resonator and the dummy electrode lie laterally next to each other in a common plane.
5 . The electric component according to claim 3 , wherein the dummy electrode is not electrically connected to another element for the operation of the electric component.
6 . The electric component according to claim 3 , wherein the dummy electrode is completely enclosed by the first piezoelectric layer and the carrier substrate.
7 . The electric component according to claim 1 , wherein in a region between the bottom electrode of the second BAW-resonator and the carrier substrate, the first piezoelectric layer is in direct contact to the carrier substrate.
8 . The electric component according to claim 1 , wherein the top electrode of the first BAW-resonator and the bottom electrode of the second BAW-resonator lie next to each other in a common plane.
9 . The electric component according to claim 1 , wherein:
the electric component is or comprises an RF-filter, and
the first BAW-resonator is a serial resonator and the second BAW-resonator is a shunt resonator or vice versa.
10 . The electric component according to claim 1 , wherein the carrier substrate comprises layers of different acoustic impedances stacked above each other along a direction perpendicular to the top side.
11 . The electric component according to claim 1 , wherein the first and the second BAW-resonator have different resonant frequencies.
12 . The electric component according to claim 1 , wherein the electric component is a chip.
13 . The electric component according to claim 1 , wherein the first piezoelectric layer laterally extends beyond the top electrode and the bottom electrode of the first BAW-resonator.
14 . A method for manufacturing an electric component, comprising:
providing a carrier substrate;
depositing a first electrode layer on a top side of the carrier substrate;
thereafter depositing a first piezoelectric layer on the first electrode layer;
thereafter depositing a second electrode layer on the first piezoelectric layer;
thereafter depositing a second piezoelectric layer on the second electrode layer;
thereafter depositing a third electrode layer on the second piezoelectric layer; and
thereafter removing the second piezoelectric layer in a region of a first BAW-resonator and keeping at least a portion of the third electrode layer and of the second piezoelectric layer in a region of a second BAW-resonator.
15 . The method according to claim 14 , wherein a bottom electrode of the first BAW-resonator is formed out of the first electrode layer.
16 . The method according to claim 14 , wherein a dummy electrode is formed out of the first electrode layer in the region of the second BAW-resonator.
17 . The method according to claim 14 , wherein a top electrode of the first BAW-resonator and a bottom electrode of the second BAW-resonator are formed out of the second electrode layer.
18 . The method according to claim 14 , wherein a top electrode of the second BAW-resonator is formed out of the third electrode layer.
19 . The method according to claim 14 , wherein the electrode layers and/or the piezoelectric layers are deposited by sputtering or vapor deposition.