Semiconductor sensor

Details Semiconductor sensor Semiconductor sensor

1989-09-05

1992-05-19

James, Andrew J.

357 15, 357 27, 357 55, H01L 2984, H01L 2996, H01L 2948, H01L 2956

Patent

active

051152924

ABSTRACT:
This invention relates to a semiconductor sensor for detecting external physical forces, such as acceleration, contact pressures, air pressures, mechanical vibrations, etc. The semiconductor sensor according to this invention is characterized by the use of compound semiconductors of high piezoelectricity, such as GaAs, etc. Conventionally sensors of the cantilever type, diaphragm type, etc. are made of silicon. These prior art sensors have low detection sensitivity, and their characteristics tend to deteriorate. The sensor according to this invention is made of GaAs, which has high piezoelectricity and can retain good characteristics of the semiconductor even at high temperatures and includes a field-effect transistor formed on the GaAs for sensing a stress. The FET is driven by a constant current or a constant voltage so as to detect a change of an electrical characteristic (e.g., threshold characteristic) due to a stress. The structure of the sensor according to this invention enables the sizes of the sensors not only to be diminished but also to reduce the fabrication costs. When a stress is applied to the FET, the transconductance changes, and the temperature changes, consequently the I-V characteristic changes. An a.c. signal biased by a direct current is supplied to the gate of the FET, and a drain current is detected in an a.c. component and a d.c. component so as to detect a temperature concurrently with a detection of a stress.

REFERENCES:
patent: 3624315 (1971-11-01), Broce et al.
patent: 3740689 (1973-06-01), Yamashita
patent: 4522472 (1985-06-01), Sulouff et al.
patent: 4658279 (1987-04-01), Guckel
patent: 4706100 (1987-11-01), Tufte
patent: 4706374 (1987-11-01), Murakami
patent: 4791471 (1988-12-01), Onodera et al.
Conragen et al. "Piezoelectric FET Strain Transducers" 1970 Solid State Symposium Jun. 18, 1970 pp. 52-55.

Affiliated with

Also associated with

Rating

Semiconductor sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Semiconductor sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor sensor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2419132