Method of fabricating thin film piezoelectric device
US5801069A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1996 |
| Grant date | Sep 1, 1998 |
| Priority date | — |
| Expiry date | Jan 31, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H2003/023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A method of fabricating a thin film piezoelectric device includes preparing a semiconductor substrate having a surface; forming an etch stopping layer having an etching rate on the surface of the semiconductor substrate; forming a first semiconductor layer having an etching rate higher than the etching rate of the etch stopping layer on the etch stopping layer; forming a first electrode on a region of the first semiconductor layer; forming a piezoelectric film on the first electrode; forming a second electrode on the piezoelectric film; and etching a portion of the first semiconductor layer where the first electrode, the piezoelectric film, and the second electrode overlap, from the surface of the first semiconductor layer, selectively with respect to the etch stopping layer, thereby forming a cavity in the first semiconductor layer. Even when a compound semiconductor is employed as the substrate, the etching forming a cavity is stopped at the etch stopping layer in the direction perpendicular to the surface of the first semiconductor layer so that a cavity having a uniform depth is produced with high controllability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.