Semiconductor pressure sensor with slanted resistors
US4400681A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 1981 |
| Grant date | Aug 23, 1983 |
| Priority date | — |
| Expiry date | Feb 23, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L9/0054
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A diaphragm is formed in a silicon chip by etching a rectangular cavity in one side thereof and piezoresistive resistors are formed in the other surface of the chip to sense stress changes on the diaphragm due to pressure changes. At least one resistor is placed along the edge of the diaphragm where a sharp stress peak occurs. To avoid the problem of inaccurate placement of the resistor relative to the peak, the resistor is slanted with respect to the stress ridge at a small angle of 10.degree. to 20.degree.. This makes the resistor placement and cavity alignment much less critical thereby assuring greater uniformity of response from one sensor to another at the expense of signal size for a given pressure change on the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.