# US 10,310,026 B2 · Bias field generation for a magneto sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,310,026 B2 - Document ID: US10310026B2 - Status: Granted - Kind: B2 - Application number: 15/595,136 - Filed: 2017-05-15 - Published: 2017-08-31 - Granted: 2019-06-04 - Earliest claimed: 2008-05-30 - Assignees: Infineon Technologies AG - Applicants: Infineon Technologies AG - Inventors: Tobias Werth; Klaus Elian; James Sterling - Web page: https://patentgrep.com/patent/US10310026B2 ## CPC - G01R 33/0023: {Electronic aspects, e.g. circuits for stimulation, evaluation, control; Treating the measured signals; calibration (G01R33/0017 takes precedence)} - B82Y 25/00: Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance - G01D 5/12: using electric or magnetic means (G01D5/06 takes precedence) - G01D 5/16: by varying resistance - G01R 3/00: Apparatus or processes specially adapted for the manufacture {or maintenance} of measuring instruments {, e.g. of probe tips} - G01R 33/0052: {Manufacturing aspects; Manufacturing of single devices, i.e. of semiconductor magnetic sensor chips (devices based on galvano-magnetic effect or the like H10N50/85)} - G01R 33/072: {Constructional adaptation of the sensor to specific applications} - G01R 33/09: Magnetoresistive devices - G01R 33/091: {Constructional adaptation of the sensor to specific applications} - G01R 33/093: {using multilayer structures, e.g. giant magnetoresistance sensors (thin magnetic films H01F10/00)} - G01R 33/098: {comprising tunnel junctions, e.g. tunnel magnetoresistance sensors} - H10N 50/10: Magnetoresistive devices - G11B 2005/0008: {Magnetic conditionning of heads, e.g. biasing} - Y10T 29/49002: Electrical device making - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - G01D: MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Embodiments related to the generation of magnetic bias fields for magnetic sensing are described and depicted. In one embodiment, a sensor includes at least one magnetosensitive element, and a magnetic body with an opening, the magnetic body comprising magnetic material, the magnetic body having inclined surface sections shaped by the opening, wherein the sensor is arranged within the opening such that the magnetosensitive element is in lateral directions bounded by the inclined surface sections. ## Claims ### Claim 1 A device comprising: a magnetic sensor; and a bias field generator including a cavity having a width along a first direction, wherein the width increases from a minimum width to a maximum width as a distance from the magnetic sensor along a second direction orthogonal to the first direction increases, the minimum width of the cavity being smaller than a width of the magnetic sensor. ### Claim 2 (depends on 1) The device according to claim 1, wherein the cavity is defined by two or more inclined surfaces. ### Claim 3 (depends on 2) The device according to claim 2, wherein the cavity is pyramidal. ### Claim 4 (depends on 1) The device according to claim 1, wherein the cavity is conical. ### Claim 5 (depends on 1) The device according to claim 1, wherein the cavity is pyramidal. ### Claim 6 (depends on 2) The device according to claim 2, wherein an inclination angle between at least one of the inclined surfaces and the second direction is in a range between 5° and 20°. ### Claim 7 (depends on 1) The device according to claim 1, wherein the bias field generator is configured to generate a magnetic field such that a lateral magnetic field component of the magnetic field is substantially zero along the second direction at a location of the magnetic sensor. ### Claim 8 (depends on 1) The device according to claim 1, wherein a package is formed by molding around the magnetic sensor and the bias field generator. ### Claim 9 (depends on 1) The device according to claim 1, wherein the cavity is filled with a material that is non-magnetic and non-magnetizable. ### Claim 10 A device comprising: a magnetic sensor; and a bias field generator arranged adjacent to the magnetic sensor in a first direction, the bias field generator including a cavity formed in the bias field generator and defined by first and second inclined surfaces, the cavity having a width along a second direction orthogonal to the first direction that increases from a minimum width to a maximum width as a distance from the magnetic sensor along the first direction increases, wherein the magnetic sensor is laterally bound by the first and the second inclined surfaces in the second direction, the minimum width of the cavity being smaller than a width of the magnetic sensor. ### Claim 11 (depends on 10) The device according to claim 10, wherein: the cavity is further defined by third and fourth inclined surfaces; and the magnetic sensor is further laterally bound by the third and the fourth inclined surfaces in a third direction orthogonal to the second direction and orthogonal to the first direction. ### Claim 12 (depends on 10) The device according to claim 10, wherein the cavity is pyramidal. ### Claim 13 (depends on 10) The device according to claim 10, wherein an inclination angle between at least one of the first and second inclined surfaces and the second direction is in a range between 5° and 20°. ### Claim 14 (depends on 10) The device according to claim 10, wherein the bias field generator is configured to generate a magnetic field such that a lateral magnetic field component of the magnetic field is substantially zero along the second direction at a location of the magnetic sensor. ### Claim 15 (depends on 10) The device according to claim 10, wherein a package is formed by molding around the magnetic sensor and the bias field generator. ### Claim 16 (depends on 10) The device according to claim 10, wherein the cavity is filled with a material that is non-magnetic and non-magnetizable. ### Claim 17 A device comprising: a magnetic sensor; and a bias field generator arranged with respect to the magnetic sensor in a first direction, the bias field generator including a cavity formed in the bias field generator and extending into the bias field generator in the first direction, wherein a cross-sectional area of the cavity defined in a plane that extends along a second direction orthogonal to the first direction and along a third direction orthogonal to the first and the second directions increases from a minimum cross-sectional area to a maximum cross-sectional area as a distance from the magnetic sensor along the first direction increases, the minimum cross-sectional area of the cavity being smaller than a cross-sectional area of the magnetic sensor defined in the plane. ### Claim 18 (depends on 17) The device according to claim 17, wherein the bias field generator is arranged below the magnetic sensor in the first direction. ### Claim 19 (depends on 17) The device according to claim 17, wherein the magnetic sensor is disposed within the cavity and is laterally bound by the cavity in the second direction and the third direction. ### Claim 20 (depends on 17) The device according to claim 17, wherein the cavity is pyramidal or conical.