METHOD OF FABRICATING AN ELECTRODE FOR A BULK ACOUSTIC RESONATOR
First Claim
1. A method of producing a resonator in thin-film technology, the resonator comprising a piezoelectric layer arranged at least partially between a lower electrode and an upper electrode, the resonator being formed over a substrate, the method comprising:
- forming the lower electrode of the resonator over the substrate;
depositing and patterning an insulating layer over the substrate, the insulating layer comprising a thickness substantially equal to a thickness of the lower electrode;
removing a portion of the insulating layer to partially expose a surface of the lower electrode;
removing a portion of the insulating layer over the surface of the lower electrode by chemical mechanical polishing;
forming the piezoelectric layer over the lower electrode; and
producing the upper electrode on the piezoelectric layer.
4 Assignments
0 Petitions
Accused Products
Abstract
In one embodiment, a method of producing a resonator in thin-film technology is described. The resonator comprises a piezoelectric layer arranged at least partially between a lower electrode and an upper electrode, the resonator being formed over a substrate. The method comprises: forming the lower electrode of the resonator over the substrate; depositing and patterning an insulating layer over the substrate, the insulating layer comprising a thickness substantially equal to a thickness of the lower electrode; removing a portion of the insulating layer to partially expose a surface of the lower electrode; removing a portion of the insulating layer over the surface of the lower electrode by chemical mechanical polishing; forming the piezoelectric layer over the lower electrode; and producing the upper electrode on the piezoelectric layer.
71 Citations
21 Claims
-
1. A method of producing a resonator in thin-film technology, the resonator comprising a piezoelectric layer arranged at least partially between a lower electrode and an upper electrode, the resonator being formed over a substrate, the method comprising:
-
forming the lower electrode of the resonator over the substrate; depositing and patterning an insulating layer over the substrate, the insulating layer comprising a thickness substantially equal to a thickness of the lower electrode; removing a portion of the insulating layer to partially expose a surface of the lower electrode; removing a portion of the insulating layer over the surface of the lower electrode by chemical mechanical polishing; forming the piezoelectric layer over the lower electrode; and producing the upper electrode on the piezoelectric layer. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A method of producing a resonator in thin-film technology, the resonator comprising a piezoelectric layer arranged at least partially between a lower electrode and an upper electrode, the resonator being formed over a substrate, the method comprising:
-
forming the lower electrode of the resonator over the substrate; forming a protection layer over the lower electrode; depositing an insulating layer over the substrate and partially over the protection layer, the insulating layer comprising a thickness substantially equal to a combined thickness of the lower electrode and the protection layer; removing the insulating layer over the portion of the protection layer; forming the piezoelectric layer over the protection layer; and forming the upper electrode over the piezoelectric layer. - View Dependent Claims (10, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
- 11. A method as claimed in claim 11, wherein the protection layer comprises a lower removal by chemical-mechanical polishing rate than a removal rate of the lower electrode.
Specification