Microfabricated acoustic transducer with suppressed substrate modes
US6714484B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2002 |
| Grant date | Mar 30, 2004 |
| Priority date | — |
| Expiry date | Oct 25, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB06B2201/76
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A microfabricated acoustic transducer with suppressed substrate modes includes a diaphragm containing an upper electrode suspended above a substrate containing a lower electrode; the substrate may or may not contain electronic circuits. The substrate modes are suppressed by either thinning the substrate such that a longitudinal ringing mode occurs outside of the frequency band of interest or applying a judiciously designed damping material that absorbs acoustic energy from the substrate on the backside of the transducer substrate, or by both thinning the substrate and applying the damping material. The damping material has an acoustic impedance that matches the acoustic impedance of the substrate and is lossy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.