Force sensor with a piezoelectric FET
US4480488A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1983 |
| Grant date | Nov 6, 1984 |
| Priority date | — |
| Expiry date | Feb 16, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L1/18
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A force sensor comprising a field effect transistor (FET) structure formed on a substrate, having an insulating layer overlying the substrate adjacent to the channel region of the transistor structure. A layer of piezoelectric material overlies the insulating layer, the layer of piezoelectric material having a portion which extends beyond the insulating layer to form a cantilever structure overhanging a portion of the channel region. A control electrode overlies the cantilever structure. Forces acting on the cantilever structure modify the charge distribution in the underlaying channel region, thereby to cause the drain current of the transistor to vary with any variation of force on the cantilever structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.