Integrated set/reset driver and magneto-resistive sensor

The present invention generally relates to magnetic field and current sensors, and more specifically, but not limited to, signal processing for magnetoresistive sensors.

This application was filed by (1) Inventors Mark D. Amundson and William F. Witcraft, 6 2003. US Provisional Patent Application No. 60 / 475,175 filed on March 2, Honeywell Document No. H0004 956 "Die Top Set / Reset Driver for Reluctance Sensors", (2) US Provisional Patent Application No. 60 / 475,191 filed June 2, 2003 by inventors Lonny L. Berg and William F. Witcraft, Honeywell Document No. H0004602 "Magnetic resistance of semiconductor devices" Integration with sensors , (3) Inventor William F. Witcraft, Hong Wan, Cheisan J. Yue And Tamara K. Bratland, US Provisional Patent Application No. 60 / 462,872, filed April 15, 2003, Honeywell Document No. H0004948, "Integrated GPS Receiver and Reluctance Sen." Request the benefit of "Sir device". This application incorporates all of these provisional patent applications here as references.

This application also includes (1) the currently pending US patent application by the inventors Lonny L. Berg and William F. Witcraft.<u style="single"></u>No., Honeywell Document No. H0004602 US "Magnetic defects in semiconductor devices Integration with anti-sensors , (2) Inventors William F. Witcraft, Hong Wan, Cheisan J. Yue And Tamara K. Bratland's currently pending U.S. Patent Application No.<u style="single"></u>No., Honeywell Document Number H 0004948US It is also related to "Integrated GPS receiver and magnetoresistive sensor device", and these are incorporated here as references.

Magnetic field sensors are used for magnetic compass, iron metal detection and current sensing. Magnetic field sensors detect changes in magnetic fields within mechanical elements, Earth's magnetic fields, underground minerals or electrical equipment and wiring.

In magnetic sensors, especially anisotropic magnetoresistive (AMR) bridge sensors, a thin film of magnetoresistive material is placed on a silicon substrate to accurately measure the strength and / or direction of the local magnetic field. Since the manufacturing process of a semiconductor foundry can be used to deposit a thin film on a silicon substrate, another step of making adjacent semiconductor circuit elements can be added. These semiconductor circuit elements are not conventionally arranged coexisting on the same substrate as the magnetoresistive sensor because the thin film of the sensor and the conventional semiconductor manufacturing process are incompatible.

Reluctance sensors typically use permalloy, a ferromagnetic alloy containing nickel and iron, as the reluctance material. Permalloys are often arranged as thin strips of permalloy film. When the current flows through the individual strips, the magnetization direction of the strips forms an angle with respect to the direction of the current. When the direction of magnetization changes, the effective resistance of the strip also changes. Specifically, in the magnetization direction parallel to the current flowing direction, the resistance over the strips is maximized, and in the magnetization direction perpendicular to the current flowing direction, the resistance across the strips is minimized. This change in resistance changes the voltage drop across the strip as the current flows through the strip. This change in voltage can be measured as representing a change in the magnetization direction of the external magnetic field acting on the strip.

Several pieces of permalloy are electrically connected together to form the magnetic field sensing structure of the reluctance sensor. The permalloy strips are placed on the board of the reluctance sensor as a continuous resistor with a "herringbone" pattern, or as a linear strip of magnetoresistive material, at an angle of 45 degrees to the long axis of the reluctance. A conductor is provided across the piece. This latter configuration , Known as "Bias of Barber's Sign Pillars". This causes the current in the strip to flow at an angle of 45 degrees with respect to the long axis of the strip due to the construction of the conductor. The design of these sensing structures is discussed in US Pat. No. 4,847,584, July 11, 1989, published by Bharat B. Pant and assigned to the same assignee as this application. The entire US Pat. No. 4,847,584 is incorporated herein by reference. Other patents and patent applications that describe magnetic sensor technology are described below in connection with the discussion in Figure 2.

Magnetic sensors often include a number of reorienting elements or "straps" through which current flows to control and adjust sensing characteristics. For example, magnetic sensor designs often include set / reset and / or offset redirection elements or "straps" (hereinafter referred to as "set / reset straps" and "offset straps").

The offset strap acts to offset or compensate for the external magnetic field. The set / reset strap helps to orient the reluctance thin film particle structure for maximum measurement accuracy. This process of reluctance film uses the magnetization of the set / reset strap to apply intense magnetic field strength for a short period of time, directing thin film particles in virtually one direction. By applying this short magnetic field, the thin film is "set" in one direction. By applying a second short magnetic field of similar intensity but opposite direction, the direction of the thin film particles is "reset". By repeating the set and / or reset magnetic field, the thin film particles can be reliably maintained in a relatively known magnetic direction in an undisturbed state.

The set / reset strap itself is usually located on the chip, but the driver circuitry for this strap is usually located outside the chip, which makes space inefficient. When placed off-chip, current is usually pulsed through one or more straps (usually metal) to the reluctance sensor bridge, but an external board is used to toggle the switch to generate the current pulse. Level circuits are used.

Similarly, other components such as operational amplifiers, transistors, capacitors, etc. are usually mounted on a chip separate from the magnetic sensor. For example, signal conditioning and electrostatic discharge circuits are typically located off-chip. This is preferable for some products, but for others where physical space is valuable, one or more of these semiconductor components may be part of the same chip as the magnetic sensor. It is desirable to be there. Therefore, a single chip design, especially one with a set / reset driver circuit located on the chip, is desirable.

<p num="0012"> It discloses a magnetic sensor, how to make it, and how to use it. The sensing device controls or drives one or more reluctance sensing elements for detecting or measuring a magnetic field, one or more reluctance elements for adjusting the reluctance sensing elements, and a reluctance element. Includes a semiconductor circuit having a driver circuit for. The reluctance sensing elements, turning elements, and semiconductor circuits are all located in a single package and / or monolithically formed on a single chip.</p>

Preferred embodiments of the present invention will be described below in association with the accompanying drawings, but similar elements are given similar reference numbers throughout the drawings.

In view of the wide variety of embodiments to which the principles of the invention can be applied, it should be understood that the illustrated embodiments are merely examples and do not limit the scope of the invention.

Typical structure FIG. 1 is a simplified block diagram showing the integration of one or more semiconductor device components with one or more magnetoresistive elements according to an embodiment. In general, the term "integrated" or "integrated" means that one or more subsystems are contained within a larger system. On the other hand, "integrated" means that its subsystems, structures and functions are mixed with other parts of a larger system. Unless otherwise specified, the terms "integrated" and "integrated" are used interchangeably in this description to describe a composite assembly with either or both definitions.

Device 100 includes first and second parts 102, 104. The first part 102 includes a magnetoresistive sensing element (hereinafter collectively referred to as MR sensor) and wiring such as a thin film trace. The second part 104 includes one or more semiconductor device components such as a set / reset driver circuit. In certain preferred embodiments, the second portion 104 further includes a signal conditioning circuit and an ESD (electrostatic discharge) protection circuit for the MR sensor of the first portion 102. As discussed below, Part 2 104 is particularly suitable for standard semiconductor manufacturing techniques such as those used in CMOS (Complementary Metal Oxide Semiconductors).

Since the first and second parts 102, 104 are located in the same chip, the device 100 is a separate, one-chip, i.e., monolithic design. In prior art attempts to integrate semiconductor devices with MR sensors, at least two dies are typically placed individually on the printed circuit board and end user devices (eg, mobile phone, mobile device, clock, automotive sensors). Etc.) became large and became more complicated. The device 100 with a one-chip design can be reduced in size and added functions.

The first and second parts 102, 104 can be manufactured using standard RF microwave processing, such as CMOS, bipolar, bipolar CMOS, GaAs (gallium arsenide) and InP (indium phosphide). it can. Techniques such as GaAs can offer advantages in terms of processing speed, but use other techniques such as SOI (Silicon on Insulator) or MOI (Microwave on Insulator), techniques that include variations of SOI. Then, the power consumption can be reduced to the maximum. In some embodiments, a 0.35 μ treatment of SOI is used.

In certain preferred embodiments, Part 1 102 is manufactured using standard lithography, metal coatings and etching processes as described in the list of patents referenced below. .. However, other techniques for manufacturing MR sensors may be used. The second part 104 is preferably manufactured using another RF / microwave method such as 0.35μ treatment of SOI or GaAs treatment.

Integrating an MR sensor with one or more semiconductor device components can be achieved in at least one of two methods. In the first embodiment, the MR sensor can be made on the same die as the semiconductor device component and may include other circuitry such as signal conditioning and ESD protection circuitry. In the second embodiment, the MR sensor is mounted on the first die and at least some of the semiconductor device components are mounted on the second die.

The first and second dies may be placed in close proximity to each other and packaged within a single integrated circuit (integrated circuit) chip. In either case, it is convenient to include one or more connections between the semiconductor device component and the MR sensor, depending on the specific application. For example, such a connection provides feedback. Instead, the semiconductor device components and the MR sensor are physically close to each other, but may not have intentional electrical interactions.

Specific semiconductor device circuits are flexible because conventional semiconductor processing techniques can be used. Therefore, it is not disclosed here. Therefore, conventional semiconductor designs that can be implemented in CMOS / bipolar / bipolar CMOS can be used according to the currently disclosed embodiments. Typical semiconductor devices that can be implemented include, but are not limited to, capacitors, inductors, operational amplifiers, set / reset circuits for MR sensors, accelerometers, pressure sensors, position sensing circuits, compass circuits, etc. There is.

Some semiconductor device components generate an electromagnetic field that affects the operation of the MR sensor. Therefore, the sensitive portion of the MR sensor portion 102 of the integrated device 100 must be physically separated from the portion of the semiconductor device portion 104 in order to optimize the operation of the sensor. The amount of separation is determined, for example, using theoretical or experimental means. Instead of introducing physical separation between the potentially interfering parts of the integration device 100, a shielding layer may be provided, as described in US Provisional Patent Application No. 60/475191. Typical production technique FIG. 2 shows a typical cross section of the device 200, in which one or more semiconductor components, such as the semiconductor components used with the set / reset driver circuit, are mounted together with the MR sensor. This example assumes CMOS / bipolar semiconductor technology. The semiconductor device components (including all signal conditioning circuits and drivers for the set and / or offset strap associated with the MR sensor portion) are built primarily in the CMOS / bipolar underlayer, and the MR sensor is on the contact glass layer 208. Manufactured in the upper layers 202-206. In addition, FIG. 2 shows various contacts V1-V3 and metal-coated M1-M3 and a NiFe permalloy structure (see first insulator layer 206). In addition to the lower layer 210, the contact glass layer 208 and the first insulator layer 206, the second insulator layer 204 and the inactivating layer 202 are also shown.

In some embodiments, layers 202-206 are formed using standard lithography, metal coating and etching treatments, and layers 208-210 are RF / such as 0.35μ treatment of SOI or GaAs treatment. It is formed using the microwave method. Other components of the MR sensor (set, reset and offset straps; signal conditioning circuits, and ESD protection circuits) are contained in various locations within layers 206-210, all of which are shown in Figure 2. Not in. Typical reluctance design To better understand the MR sensor design, the following Honeywell patents and / or Will refer to patent applications, the entire of which is incorporated herein by reference.<u style="single">(1) US Pat. No. 6,529,114 "Magnetic Field Sensing Device" to Bohlinger et al.</u> The device includes a two-axis integrated device for measuring magnetic fields, including two sensor units made of MR material with an anisotropic magnetic field direction in quartz. The element of the first sensor of the two sensor units has a total anisotropy magnetic field in the first direction. The element of the second sensor in the two sensor units has a total anisotropic magnetic field in the second direction perpendicular to the first direction. Means for setting the direction of magnetization within the elements of the first and second sensor units are provided. The output of the first sensor unit represents the magnetic field component perpendicular to the first direction, and the output of the second sensor represents the magnetic field component perpendicular to the second direction.<u style="single">(2) US Pat. No. 6,232,776 to Pant et al. ("Pant et al.'S patent") "Magnetic field sensor for isotropically sensing the incident magnetic field on the sensor surface"</u> The Pant et al. Patent provides a magnetic field sensor that isotropically senses an incident magnetic field. This is preferably achieved by providing a magnetic field sensor device with one or more circular MR sensor elements for sensing the incident magnetic field. The MR material used is preferably isotropic and is either an extraordinary magnetoresistive (CMR) material or some form of giant magnetoresistive (GMR) material. Since the sensor element is circular, shape anisotropy is minimized. Therefore, the resulting magnetic field sensor device provides an output that is relatively independent of the direction of the incident magnetic field on the sensor surface.

In one embodiment of Pant et al.'S patent, the magnetic field sensor includes a first leg and a second leg. The first leg is connected between the output net and the first power supply terminal. The second leg is connected between the output net and the second power supply terminal. At least one circular sensor element made of MR material is incorporated in at least one of the first and second legs to isotropically sense the incident magnetic field. It is desirable that two or more circular MR sensor elements be incorporated into one of the first or second leg, the other leg being made of non-reluctance material. It is desirable that the two or more circular sensor elements be connected in series via a number of non-reluctance connectors to form the corresponding legs.

To maximize the sensitivity of the magnetic sensor device, the circular sensor element is preferably made of CMR material. However, it is also possible to use GMR materials. The CMR material shown is generally of formula (LnA) MnO.₃Represented by, where Ln is La, Nd or Pr and A is Ca, Sr, Ba or Pb. The CMR material is LaCaMnO, preferably with a La concentration of 26-32 atomic percentages, a Ca concentration of 9-20 atomic percentages, and a Mn concentration of 47-64 atomic percentages.

In another embodiment of the Pant et al. Patent, the magnetic field sensor includes a first leg, a second leg, a third leg and a fourth leg. It is desirable that the first leg and the second leg are connected between the first output net and the second output net, respectively, and the first power supply terminal. It is desirable that the 3rd and 4th legs are connected between the 1st output net and the 2nd output net and the 2nd power supply terminal. In order to sense the incident magnetic field isotropically, at least one circular sensor element made of MR material is placed on at least one of the first, second, third and fourth legs. It has been incorporated. It is desirable that the first and fourth legs are each made of two or more circular MR sensor elements, and the second and third legs are made of non-reluctance material. For each of the first and fourth legs, it is desirable that two or more corresponding circular sensor elements be connected in series by a number of non-reluctance connectors to form the corresponding leg. The circular MR sensor element is preferably made of the same CMR material as described above.<u style="single">(3) US Pat. No. 5,952,825 to Wan ("Wan's Patent") "Magnetic Field Sensing Device with Integrated Coil to Create Magnetic Field"</u> Wan's patent provides both set / reset properties and independent properties that use a unique coil arrangement to create a known magnetic field in the magnetic sensing element. The presence of both of these characteristics in the magnetic field sensor increases the functionality of the sensor well beyond the sum of the individual functions with the two characteristics.

To facilitate this, Wan's patent provides a means for setting and resetting the magnetic region in MR sensors located within an electrical bridgework network and the direction of magnetization in the opposing bridgeway elements. Uses a very small low power device including a current strap for setting. The directions of magnetization in the opposing bridge elements may be set in the same direction or in opposite directions, depending on the specific design. The current strap creates a known magnetic field in the magnetic field sensing element. Known magnetic fields are used for functions such as testing, setting, correction, calibration, as well as feedback applications.<u style="single">(4) US Pat. No. 5,820,924 to Witcraft et al. "How to Make a Reluctance Sensor"</u> The patents of Witcraft et al. Are (i) the stage of manufacturing a magnetic field sensor including the stage of providing a silicon substrate, and (ii) the stage of forming an insulating layer on the substrate and generating a first magnetic field as a new line. (iii) Form the layer in the presence of a first magnetic field of the MR material on the insulating layer. Provided is a method comprising: (iv) determining the first value of the anisotropic magnetic field, and (v) annealing at a temperature chosen to provide the desired anisotropic magnetic field. doing.<u style="single">(5) US Pat. No. 5,247,278 to Pant et al. ("Pant et al.'S Patent II") "Magnetic</u><u style="single">World sensing device "</u> Patent II of Pant et al. Provides set / reset characteristics and an independent function to create a known magnetic field in the magnetic sensing element. The presence of both of these characteristics in the magnetic field sensor increases the functionality of the sensor well beyond the sum of the individual functions with the two characteristics.

In some embodiments, Pant et al.'S patent II includes a device for setting and resetting the magnetic region within an MR sensing element located within an electrical bridge network. The current straps are provided so that the directions of magnetization within the opposing bridge elements are set in the same or opposite directions, depending on the specific design. In another aspect of the invention, the second current strap creates a known magnetic field in the magnetic field sensing element. Known magnetic fields are used for functions such as testing, setting, and calibration.<u style="single">(6) Witcraft et al. US Patent Application No. 09 / 947,733 (Witcraft et al. Patent II) Methods and systems for improving the efficiency of sets and offset straps on magnetic sensors</u> Witcraft et al.'S Patent II provides a method for manufacturing magnetic field sensors, including the step of providing the keeper material in close proximity to the magnetic field sensing structure. The sensor includes a substrate, a current strap and a magnetic field sensing structure.

Witcraft et al.'S Patent II also offers either set-reset straps or offset straps as current straps. This embodiment may further include both set-reset straps and offset straps within the same sensor. In another embodiment, the magnetic field sensing structure further comprises permalloy strips that are electrically connected to each other and to the output terminals, where a magnetic field display is created.<u style="single">(7) Wan et al. US Patent Application No. 10 / 002,454 ("Wan et al.'S Patent II") "360 Degree Rotating Position Sensor"</u> In Wan et al.'S Patent II, the 360-degree rotating position sensor has a Hall sensor and an MR sensor. One of the magnets or the 360 degree rotating position sensor is attached to the rotating shaft. Since the 360-degree rotary position sensor is placed so close to the magnet, it can detect the magnetic field generated by the magnet. The Hall sensor detects the polarity of the magnetic field. The MR sensor detects the angular position of the magnetic field up to 180 degrees. By combining the output from the Hall sensor and the output from the MR sensor, the angular position of the magnetic field can be detected up to 360 degrees.<u style="single">(8) U.S. Pat. No. 5,521,501 to Dettmann et al. ("Dettmann et al.'S patent") "Magnetic field sensor made of remagnetized wire and one or more reluctance resistors"</u> The Dettmann et al. Patent is a single magnetic field dependent resistor with one or more MR thin film strips on a highly conductive thin film conductor strip arranged in an insulating fashion perpendicular to the longitudinal direction of the magnetic field dependent resistor. We provide vessels. The highly conductive thin film conductor strip is provided with a meandering structure. Serpentine strips with alternating magnetic field directions are placed adjacent to each other, and resistance under current flow despite resistance changing equidirectionally in all subranges under the influence of the magnetic field to be measured. The MR thin strips are divided into areas with a barber signpost-like structure that is inclined in the opposite direction at an angle to the longitudinal direction of the strips.

Since the highly conductive thin film conductor strips meander, it is convenient because the current required to reverse the direction of magnetization is small. Further, the magnetic fields of the meandering strips arranged adjacent to each other greatly cancel each other because they are in opposite directions, so that the stray magnetic field existing on the outside of the sensor chip is very low. Therefore, the magnetic field sensors can be operated in close proximity to each other. For the same reason, the inductance of the remagnetized conductor is also very low, so that the inductance does not limit the measurement frequency.

When the magnetic field sensor is operated by an MR resistor, a constant current is supplied to the MR resistor. The voltage of the MR resistor is measured as an output signal. Highly conductive thin film conductor with current pulse in one direction As it flows through the strips, the self-magnetization within the region of the MR resistor is set in some way. In this state, the magnetic field to be measured increases the resistance value of the MR resistor. This means that the output signal is larger in the absence of a magnetic field. Then, when a pulse of a current in the opposite direction to the previous pulse is sent to the highly conductive thin film conductor strip, the direction of self-magnetization is reversed. Therefore, the resistance of the magnetic field to be measured is reduced, and the output voltage is smaller than when there is no magnetic field. If the direction of the pulse changes constantly, an AC voltage with an amplitude proportional to the magnetic field to be measured will be present at the output. All effects, such as temperature leading to slow drift of the resistance of MR thin film strips, do not affect the AC output voltage. However, as the temperature at the output AC voltage amplitude increases, a decrease in the MR effect is observed.

Therefore, in another embodiment, more highly conductive thin film strips are provided under all MR thin film strips. The current through these high-conductivity thin film strips is controlled by the output voltage of the sensor so that the applied magnetic field to be measured is just offset by the current. In this case, the MR magnetic field sensor acts as a zero detector. The output amount of this device is the amount of correction current and does not depend on the temperature of the device. Similarly, the non-linearity plays no role in the sensor characteristic curve because the sensor is not modulated.

In another embodiment of the Dettmann et al. Patent, four parallel MR resistors, each with multiple regions, are provided on top of a thin layer of remagnetized conductors and high conduction correction conductors. The barber signposts alternate between positive and negative angles from the longitudinal direction of the MR thin film strips so that each region begins with alternating positive and negative angles of the barber signpost-like structure. The structure is provided. The four resistors are connected to form a Wheatstone bridge. When the remagnetized conductors are reactivated with alternating pulses in opposite directions, an AC voltage signal appears at the output of the bridge. This signal is overlaid with only one DC voltage signal resulting from four possibly non-identical resistance values of the bridge. However, this DC voltage component is considerably smaller than when one resistor is used, and a simple evaluation is possible. Of course, the correction of the magnetic field to be measured may be adopted here as well.

The bridging device includes four resistors formed from even regions. Only the order of the angles of the barber's sign pillar-like structure changes from resistor to resistor. The direction of remagnetization is set within the region by a first strong current pulse through the remagnetizing conductor. Since the sensor bridge reacts to a magnetic field, it can be used in a conventional manner without further remagnetization. Since all four resistors in the bridge have the same area, it is expected that the same changes will occur in all resistors as the temperature of the sensor device changes. This also applies to the variable components resulting from layer voltage fluctuations and the resulting magnetic distortion. Therefore, the sensor bridge has a smaller zero point than known sensor bridge devices and is therefore also suitable for traditionally measuring smaller magnetic fields. The constant current through the remagnetized conductor acts to generate a constant and stable magnetic field, thereby setting a constant sensor sensitivity. Therefore, the patented device of Dettmann et al. Can be conveniently used for various evaluation methods of magnetic field measurement. Typical metal-insulator-metal condenser integration In order to provide the functionality of the set / reset driver circuit, the device 200 of FIG. 2 includes a large number of semiconductor device components. In addition, one or more specialized capacitors are included, such as the metal-insulator-metal (MIM) capacitor 350 shown within the first dielectric layer 206. As shown, the MIM capacitor 350 is located between the contact V1 and the nitride layer overlaid on the low resistance metal coating M1. The MIM capacitor 350 is shown to be located within the first dielectric layer 206, but instead in another location such as the inactivating layer 202, the second dielectric layer 204 or the CMOS / bipolar underlayer 210. There may be. The integrated MIM capacitor is an improvement over the linear capacitor used with the prior art MR sensor due to its small size and possibly the overall package.

The device 200 has a configuration suitable for an MR sensor, and permalloy and other configurations having different structures may be used instead. In yet another embodiment, the MIM capacitor 350 can be incorporated into the device 200 to remove the CMOS / bipolar underlayer 210 or replace it with some other base or substrate material. Integrated or integrated set / reset circuit FIG. 3 is a schematic diagram showing typical set / reset circuits 360, 362 mounted on a die or monolithically with an MR sensor according to a typical embodiment. The circuit design shown in FIG. 3 is an example of many possible designs and does not limit the present invention.

A typical circuit 360 is an amplifier circuit that raises the signal gain of the MR sensor. Two operational amplifiers with a negative feedback loop provide a differential voltage signal indicating a change in local magnetic field that is perceived across the legs of the reluctance bridge. The resistor values shown are particularly suitable for one preferred embodiment, and another resistor value and configuration is more suitable for another MR sensor design. Similarly, two op amps are shown for circuit 360, but another design uses more or less op amps with more or less bias resistors.

A typical circuit 362 is a switching circuit that generates a set / reset current pulse through a set / reset strap and appropriately directs the thin film magnetic region of the bridge circuit in an appropriate direction. Circuit 362 includes a complementary pair of field effect transistors switched by ESDR relays to provide set / reset pulses. As with circuit 360, designing and selecting a particular reluctance sensor will change the switching circuit. The illustrated resistor values are values suitable for certain preferred embodiments.

Circuit 364 is completely optional and is used for testing purposes. This demonstrates the flexibility that many application-specific characteristics can be included in the set / reset driver circuit without departing from the scope intended by the present invention. Various modifications can be made to all the circuits shown in FIG. For example, a thermal or temperature compensation circuit is included to prevent thermal drift. Integration of typical semiconductor circuits FIG. 4 is a plan view of one embodiment of device 300 in which the set / reset driver circuit is monolithically integrated with the MR sensor or on the chip. Typical parts of the device 300 are the reluctance bridge 301, set / reset strap 302, offset strap 304, set / reset circuit 306-308, laser trim site 310 (to match the impedance of the legs of the bridge 301), Includes ESD protection diode 312, MIM capacitor 314, operational amplifier 316, contacts 318 and test site 320. For more information, see the previously incorporated patents and patent applications.

Figure 5-6 is a simplified schematic 500-600 showing an example of a semiconductor circuit model integrated with an MR sensor. These representative diagrams are not intended an exhaustive or inflexible list of circuits integrated or integrated with the MR sensor, but rather the width of the circuits so combined. It is for showing.

FIG. 5 is a simplified schematic 500 showing a compass circuit 502 integrated with an MR sensor. In this embodiment, the MR sensor is made up of first and second reluctance sensing elements 504, 506. The first and second reluctance sensing elements 504, 506 sense orthogonal magnetic fields and provide first and second outputs in response. In a three-dimensional coordinate system, for example, the first reluctance sensing element 504 senses a magnetic field in the "X" direction, and the second reluctance sensing element 506 senses a magnetic field in the "Y" direction. The XY plane, of course, depends on the coordinate system May be rotated.

One or more reversing elements in the form of set / reset and / or offset straps (not shown) are formed or with the first and second reluctance sensing elements 504, 506. It is integrated. As mentioned above, these turning elements are used to control and adjust the sensing characteristics of the first and second reluctance sensing elements 504, 506.

The compass circuit 502 includes (i) an offset strap driver circuit 508 for adjusting the offset of the first and / or second reluctance sensing elements 504 and 506, and (ii) a first and / or second reluctance sensing element. A set / reset strap driver circuit 510 for ordering the set / reset of 504 and 506, and (iii) first and second reluctances. Includes first and second operational amplifiers 512, 514, for functionally adjusting the outputs of anti-sensing elements 504, 506. The strap driver circuit 508, the set / reset strap driver circuit 510, and the first and second differential amplifiers 512 and 514 are deployed in the same package as the first and second reluctance sensing elements 504 and 506. Alternatively, the circuit may be monolithically formed with the first and second magnetic resistance sensing elements 504, 506 on the same die.

The compass circuit 502 includes a temperature compensation circuit that prevents the adverse effects of the temperature of the MR sensor. Temperature compensation is in the form of, for example, thermistors, permalloy elements and / or active preparation circuits. The active preparation circuit senses a change, i.e. a decrease or increase in voltage or current due to the effects of temperature, and provides correction of the current and / or form of voltage accordingly.

Compass circuit 502 also includes another element. For details of the components of the compass circuit 502, refer to the previously incorporated patents and patent applications in addition to the present disclosure.

FIG. 6 is a simplified schematic 600 showing a second compass circuit 602 integrated with the MR sensor. In this embodiment, the MR sensor is formed of first, second and third reluctance sensing elements 604-608 capable of sensing three orthogonal magnetic fields. The first and second reluctance sensing elements 604 and 606 are manufactured on the first die, and the third reluctance sensing element 608 is manufactured on the second die. The second die may or may not be packaged with the first and second reluctance sensing elements 604,606 in this embodiment.

In a three-dimensional coordinate system, the first reluctance sensing element 604 senses the magnetic field in the "X" direction and the second reluctance sensing element 606 senses the magnetic field in the "Y" direction. The third magnetoresistance sensing element 608 senses a magnetic field in the "Z" direction.

Similar to compass circuit 502, one or more reorienting elements in the form of set / reset and / or offset straps (not shown) are on the first, second and third reluctance sensing elements 604-608. Formed or integrated with this. Compass circuit 602 is also deployed with set / reset-strap-driver circuit 610 and first, second and third differential amplifiers 612-616. The set / reset strap driver circuit 610 sets / resets the first, second and / or third reluctance sensing elements 604-608. The first, second and third differential amplifiers 612-616 are used to functionally adjust the outputs of the first, second and third reluctance sensing elements 604-608, respectively.

In this embodiment, the set / reset-strap-driver circuit 610 and all of the first, second and third differential amplifiers 612-616 are formed on the first die. However, if the reluctance sensing element 608 and the set / reset strap are formed on the second die, then the set / reset-strap-driver circuit 610 and the third differential amplifier 6 16 is interconnected with the second die. Therefore, the set / reset pulse applied to the compass circuit 602 at node 618 passes through the first die, exits the set / reset interface 620, and performs the set / reset ordering of the third reluctance sensing element 608. Proceed to the second die. Similarly, the output signal of the third magnetic resistance sensing element 608, which is scheduled for the third differential amplifier 616, proceeds to the first die through the sensor interface 622.

In another embodiment, the set / reset-strap-driver circuit 610 and some of the first, second and third differential amplifiers 612-616 are formed on the first die. Other parts, such as the set / reset-strap-driver circuit 610 and the third differential amplifier 616, are formed on the second die and interconnected to the first die. Other combinations of components of the compass circuit 602 are also possible, as will be appreciated by those skilled in the art.

Like the compass circuit 502, the differential amplifiers 612-616 are each deployed with optional adjustable offsets and gains that beneficially correct and / or cancel unwanted changes in magnetic resistance elements 604-608. The compass circuit 602 also includes a temperature compensation circuit that prevents the adverse effects of the temperature of the MR sensor as described above. Typical process for integrating semiconductor components with MR sensors Table 1 below shows a simplified and representative process for integrating one or more semiconductor device components, such as set / reset circuits, with MR sensors. In the past, semiconductor foundry has made such a process unique because it has had considerable difficulty preventing it from being contaminated by the materials commonly used to make magnetic sensors. it is conceivable that. In addition, companies in the magnetic business (eg, disk drive head manufacturers) are distinct from electronics companies, and their specialized manufacturing techniques are very far apart from each other.

<tables num="1"><img id="000002" he="57" wi="159" file="JP5259802B2_D0001.tif" img-format="tif" img-content="drawing" /></tables> In certain preferred embodiments, the semiconductor device processing is performed at the front end and the lithography and etching steps associated with MR sensor fabrication are performed at the back end. Table 1 is intended for general application in many MR sensor manufacturing processes and therefore does not include details on how to obtain a specific configuration. In the configuration shown in FIG. 2, the backend step is repeated several times to obtain multiple layers of dielectric and metal coating. Of course, additional cleaning and other steps are also performed as appropriate.

The device having a set / reset driver circuit integrated with the MR sensor device and typical processing options have been described above. Since such an integrated device can be manufactured as a single chip, users can realize the advantage of being particularly small and versatile.

Conclusion In the above detailed description, a number of specific details are described so that the typical embodiments described herein can be fully understood. However, as you can see, these embodiments can be implemented without specific details. In another example, well-known methods, procedures, components and circuits are not described in detail so as not to confuse the subsequent description.

Furthermore, the disclosed embodiments are for illustration purposes, and other embodiments may be used in place of or combined with the disclosed embodiments. In addition, the equipment and components can be made using not only the above techniques, but also silicon / gallium arsenide (Si / GaAs), silicon / germanium (SiGe), and / or silicon / carbide (SiC) manufacturing techniques. Conceivable. Among these techniques are heterojunction bipolar transistor (HBT) fabrication processes and / or metal semiconductor field effect transistor (MESFET) fabrication processes.

Typical embodiments described herein are batteries, synchronous power sources that provide appropriate voltages such as DC of about 0.4, 5, 10, 12, 24 and 48 volts, and AC of about 24 and 120 volts. It can be deployed in a variety of equipment and other equipment that includes or is used with suitable voltage sources such as machines.

The typical embodiments have been illustrated and described above. Furthermore, the claims are not limited to the order or elements described unless the effect is stated. Furthermore, claims that use the term "means" are intended to exercise USC § 112, 6, and claims without the term "means" are not intended to do so. ..

<figref num="1">FIG. 6 is a simple block diagram showing the integration of one or more semiconductor device components with a magnetoresistive sensor according to a typical embodiment.</figref><figref num="2">FIG. 5 is a reluctance sensor with an integrated set / reset driver circuit, according to a typical embodiment.</figref><figref num="3">It is the schematic which shows the magnetic resistance sensor mounted on the die together with the set / reset circuit by a typical embodiment.</figref><figref num="4">It is a top view of the magnetic resistance sensor which has a semiconductor component according to a typical embodiment.</figref><figref num="5">FIG. 6 is a first simplified circuit diagram showing a first compass circuit integrated with a magnetoresistive sensor according to a typical embodiment.</figref><figref num="6">It is a second simplified circuit diagram which shows the 2nd compass circuit integrated with the magnetoresistive sensor by a typical embodiment.</figref>