Method to control BAW resonator top electrode edge during patterning
US8522411B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 22, 2009 |
| Grant date | Sep 3, 2013 |
| Priority date | — |
| Expiry date | Feb 6, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49156
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method of fabricating a piezoelectric resonator includes providing a bottom electrode and a piezoelectric layer coupled to the bottom electrode. A bottom metal layer of a top electrode is deposited on the piezoelectric layer. A top metal layer of the top electrode is deposited on the bottom metal layer. A photoresist layer is deposited on the top metal layer. The photoresist layer is patterned and etched. The top metal layer is patterned and etched while the etched photoresist layer remains. The bottom metal layer is patterned and etched such that an entire perimeter side surface of the top metal layer is recessed relative to a perimeter edge of the bottom metal layer. The etched photoresist layer is removed. A passivation layer is deposited on the top and bottom metal layers such that the top and bottom metal layers are isolated from a subsequent metal etch step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.