System and method for sensing a magnetic field

• US 6,960,816 B2
• Filed: 04/28/2004
• Issued: 11/01/2005
• Est. Priority Date: 04/28/2003
• Status: Expired due to Fees

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Boor, Steven E.
• Primary Examiner(s): Wilson, Allan R.
• Application Number:
  US10/834,501
• Publication Number:
  US 20040212029A1
• Time in Patent Office: 552 Days
• Field of Search: 257/423, 257/427
• US Class Current: 257/423
• CPC Class Codes: G01R 33/06 using galvano-magnetic devices

Abstract

A magnetic field sensor includes a transistor device having a base region, an emitter region, and a collector region. A barrier region disposed between the emitter region and the collector region to hamper charge carriers injected into the base region from the emitter region from reaching at least a portion of the collector region. The magnetic field sensor further includes a first voltage source to bias the collector region with respect to the base region to form a space-charge layer associated with the collector region.

Claims

1. A magnetic field sensor, comprising:

a base region;

an emitter region, wherein the emitter region is disposed in the base region; and

a collector region, wherein the collector region is disposed in the base region; and

a barrier region disposed between the emitter region and the collector region to hamper charge carriers injected into the base region from the emitter region from reaching at least a portion of the collector region, and wherein the barrier region is further disposed in the base region.

2. A magnetic field sensor comprising:

a transistor device including;

a base region;

an emitter region;

a collector region;

a barrier region disposed between the emitter region and the collector region to hamper charge carriers injected into the base region from the emitter region from reaching at least a portion of the collector region;

a first biasing source to bias the collector region with respect to the base region to form a space-charge layer associated with the collector region; and

a second biasing source to bias the barrier region with respect to the base region to control the space-charge layer associated with the barrier region.

3. The magnetic field sensor according to claim 2, further comprising:

a first sinker region disposed such that the collector region is between the first sinker region and the barrier region, the first sinker region electrically connected to the barrier region.

4. The magnetic field sensor according to claim 3, further comprising:

a second sinker region disposed such that the emitter region is between the second sinker region and the barrier region, the second sinker region electrically connected to the barrier region.

5. A magnetic field sensor comprising:

a transistor device comprising;

a base region;

an emitter region;

a collector region;

a barrier region disposed between the emitter region and the collector region to hamper charge carriers injected into the base region from the emitter region from reaching at least a portion of the collector region;

a substrate region;

a parasitic collector region; and

wherein the parasitic collector region is disposed between the base region and the substrate region.

6. The magnetic field sensor according to claim 5, further comprising:

a first sinker region disposed such that the collector region is between the first sinker region and the barrier region, the first sinker region electrically connected to the parasitic collector region.

7. The magnetic field sensor according to claim 6, further comprising:

a second sinker region disposed such that the emitter region is between the second sinker region and the barrier region, the second sinker region electrically connected to the parasitic collector region.

8. A magnetic field sensor, comprising

a transistor device including:

a base region;

an emitter region;

a collector region; and

a barrier region disposed between the emitter region and the collector region to hamper charge carriers injected into the base region from the emitter region from reaching at least a portion of the collector region;

wherein the base region is a first conductivity type and wherein the emitter region is a second conductivity type and the collector region is the second conductivity type.

9. The magnetic field sensor according to claim 8, wherein the barrier region is the first conductivity type.

10. The magnetic field sensor according to claim 8, wherein the barrier region is the second conductivity type.