Electricity: measuring and testing – Magnetic – Magnetometers
Reexamination Certificate
1999-03-10
2001-08-14
Strecker, Gerard R. (Department: 2862)
Electricity: measuring and testing
Magnetic
Magnetometers
C324S247000, C324S259000, C324S260000, C324S661000, C257S415000, C257S421000
Reexamination Certificate
active
06275034
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to semiconductor magnetic sensors or magnetometers, and more particularly to semiconductor magnetic sensors utilizing micromachined beams as the sensing element.
Magnetic sensors or magnetometers are widely used to sense magnetic fields including the Earth's magnetic field. Such devices typically operate to transform the sensed magnetomotive force to an electrical signal for processing.
Semiconductor magnetic sensors which are sensitive to magnetic fields can be quite useful in military, aviation, maritime, and scientific laboratory applications. Magnetic sensors fabricated with micromachining techniques allow for several desirable features including miniaturization, inexpensive and easily repeated fabrication and high sensitivity.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide a semiconductor magnetic sensor which yields precise and sensitive measurements of magnetic fields over a wide range of field strengths.
It is another object of the invention to provide a semiconductor magnetic sensor which accurately measures magnetic fields independent of temperature variations.
It is yet another object of the invention to provide a micromachined semiconductor magnetic sensor which is small and can be batch processed to produce consistent performance from device to device.
Accordingly, in one embodiment of the invention there is provided a device which includes at least one beam through which a current is passed, the beam being deflected perpendicularly with respect to an applied magnetic field and at least one fixed conductive member for sensing the deflection of the beam.
In another aspect of the invention there is provided a magnetic field sensor including a moveable member through which a current is passed, the moveable member being deflected perpendicularly with respect to an applied magnetic field; and at least one fixed conductive member arranged adjacent to the moveable member, the moveable member deflecting to or away from the fixed member.
In another aspect of the invention there is provided a semiconductor magnetic field sensor including a substrate; a semiconductor moveable element suspended above the surface of the substrate, the moveable element being configured to have a current passed therethrough and to deflect perpendicularly with respect to an applied magnetic field; and at least one fixed semiconductor element arranged adjacent to the moveable element, the moveable element being deflected to or away from the fixed element in response to an applied magnetic field.
In an alternative embodiment of the invention, there is provided a semiconductor magnetic field sensor including a substrate; first and second semiconductor moveable beams suspended above the surface of the substrate, the first and second beams being configured to have equal and opposite currents passed therethrough and to deflect perpendicularly with respect to an applied magnetic field; and at least one first and second fixed semiconductor elements arranged adjacent to the first and second beams, respectively, the first and second beams being deflected to or away from the respective first and second fixed elements in response to an applied magnetic field.
REFERENCES:
patent: 3911738 (1975-10-01), Fischer
patent: 4680544 (1987-07-01), Rudolf
patent: 4951510 (1990-08-01), Holm-Kennedy et al.
patent: 5036286 (1991-07-01), Holm-Kennedy et al.
patent: 5083174 (1992-01-01), Kub
patent: 5181156 (1993-01-01), Gutteridge et al.
patent: 5243861 (1993-09-01), Kloeck et al.
patent: 5315247 (1994-05-01), Kaiser et al.
patent: 5392658 (1995-02-01), Okada
patent: 5540095 (1996-07-01), Sherman et al.
patent: 5565625 (1996-10-01), Howe et al.
patent: 5659195 (1997-08-01), Kaiser et al.
patent: 5659262 (1997-08-01), Memishian
patent: 5731703 (1998-03-01), Bernstein et al.
patent: 5818227 (1998-10-01), Payne et al.
patent: 0389390 (1990-09-01), None
patent: 0392945 (1990-10-01), None
patent: 0646805 (1995-04-01), None
patent: 0816861 (1998-01-01), None
patent: 2136581 (1984-09-01), None
...,(http://ITRI.LOYOLA.EDU/mems/c3s2.html.), “Sensor Development in Japan,” Sep. 1994.
Edwards, R. Timothy, (http://BACH.ECE.JHE.EDU/~tim/papers/sensor.hmtl.,) “Microfabrication Lab Project Report: A Simple CMOS Pressure Sensor,” Dec. 1994.
Baltes, H., Castagnetti, R., Schneider, M., (http://IQE.ETHZ.CH/~fpst/FinalReport/M4/M4P02-2.html.), “LESIT Final Report 1995: Project 4.2.2: Bipolar Magnetic Field Sensors,” 1995.
...,(http://WWW.PHYS.TTU.EDU/~peters/sens.html.), “SDC Sensors”.
...,(http://WWW.ECE.NEU.EDU/edsnu/zavracky/mfl/programs/soi/soi.html.), “Silicon-on-insulator Research.”
Brokaw A. Paul
Geen John A.
Haigh Geoffrey T.
Tran Chau C.
Analog Devices Inc.
Samuels , Gauthier & Stevens, LLP
Strecker Gerard R.
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