GMR enhancement in inhomogeneous semiconductors for use in magnetoresistance sensors
AssigneeNEC Research Institute, Inc.
InventorsStuart A. Solin, Tineke Thio
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Abstract
The low-field magnetoresistance of a high carrier mobility semiconductor with inhomogeneities which are more conducting than the surrounding semiconductor material matrix is significantly enhanced compared to the magnetoresistance of the homogeneous material. The enhancement results from a magnetic field induced geometric effect in which current is expelled from the conducting inhomogeneity. The enhanced giant magnetoresistance is demonstrated at low field in (near) zero-band-gap material, such as Hg.sub.1-x Cd.sub.x Te(x.about.0.1). The effect is applied to the fabrication of magnetic read head sensors such as Corbino disc, bar magnetoresistance sensors and thin film sensors.
Claims24
A giant magnetoresistance sensor comprising:
- a matrix of high carrier mobility semiconductor material;
- electrodes coupled to said material for providing a current path through said semiconductor material;
- and
- conducting material disposed in relation to said semiconductor material for restricting the current flow between said electrodes in the presence of a magnetic field thereby increasing the magnetoresistance of the sensor.
A Corbino-disc sensor comprising:
- a matrix of high carrier mobility semiconductor material;
- an inner electrode embedded in said semiconductor material;
- an outer electrode embedded in said semiconductor material concentrically disposed relative to said inner electrode for providing a current path through said semiconductor material;
- a concentrically disposed gapped conducting ring embedded in said semiconductor material disposed between said inner electrode and said outer electrode for restricting the current flow between said inner electrode and said outer electrode in the presence of a magnetic field thereby increasing the magnetoresistance of the Corbino-disc sensor.
A bar magnetoresistance sensor comprising:
- a bar of high carrier mobility semiconductor material;
- electrodes coupled to oppositely disposed ends of said bar for providing a current path through said bar;
- and
- conducting material embedded in said bar for restricting the current flow between said electrodes in the presence of a magnetic field thereby increasing the magnetoresistance of the sensor.
A thin film sensor comprising:
- a thin film of high carrier mobility semiconductor material;
- electrodes coupled to said film for providing a current path through said film;
- and
- conducting material disposed relative to said film for restricting the current flow between said electrodes in the presence of a magnetic field thereby increasing the magnetoresistance of the sensor.
Dependencies are inferred from the claim text.