BAW resonator bi-layer top electrode with zero etch undercut
US7737612B1 · kind B1 · utility
1Cited by
19References
30Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 1, 2008 |
| Grant date | Jun 15, 2010 |
| Priority date | — |
| Expiry date | Jul 24, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49156
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A piezoelectric resonator includes a multi-layer top electrode configured such that a top most layer protects the underlying layers from subsequent etching, thereby preventing etch undercut of the top-most layer. In one embodiment, the multi-layer top electrode is configured as a bi-layer, so that the upper layer of the bi-layer stack protects all sides of the underlying layer from subsequent etch process steps. In an alternative embodiment, at least the perimeter of a multi-layer top electrode is completely covered with overlapping interconnect metal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.