JP2010133855A - Magnetic detection circuit element and magnetic sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic detection circuit element capable of reducing midpoint voltage deviation and making temperature characteristics of the midpoint voltage satisfactory by using a simple structure and a manufacturing method. <P>SOLUTION: On a semi-insulating substrate 11, a magnetoresistive element MR1 including a semiconductor film 13A and a magnetoresistive element MR2 including a semiconductor film 13B are formed in a long shape, and an input voltage electrode 14, a ground connection electrode 15, and an output voltage electrode 16 are formed. A correction electrode 16' is formed between the adjacent input voltage electrode 14 and the ground connection electrode 15. The correction electrode 16' is connected to the output voltage electrode 16 in a region different from that on a formation surface of the magnetoresistive elements MR1, MR2 of the semi-insulating substrate 11. The correction electrode 16' is set at the installation position and the size such that the leak current generated when the correction electrode 16' is not formed is canceled by a leak current newly generated by the formation of the correction electrode 16'. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnetic detection circuit element that detects an object to be detected based on a change in magnetic flux density, and a magnetic sensor using the same.

  Currently, rotation sensors using magnetism exist among various rotation sensors. And such a rotation sensor has the structure which has arrange | positioned the permanent magnet in the housing | casing, and has arrange | positioned the magnetic detection circuit element which has a magnetoresistive element in the to-be-detected body side of this permanent magnet. In this magnetic detection circuit element, a semiconductor film such as InSb whose resistance value changes due to a change in magnetic flux density is generally formed on a semi-insulating substrate such as Si, and a conductor is formed on the upper surface of the semiconductor film. A magnetoresistive element is formed by forming a plurality of short-circuit electrodes made of The magnetic detection circuit element connects a plurality (for example, a pair) of magnetoresistive elements in series, continues to apply a DC voltage having a constant value to the series circuit, and divides the voltage at the connection point of the plurality of magnetoresistive elements. The voltage is output as a detection voltage signal. Therefore, in such a magnetic detection circuit element, an input voltage electrode for applying a DC voltage, a ground connection electrode for connection to the ground, and an output voltage electrode for outputting a detection voltage signal are semi-insulating. The structure is formed on the substrate.

  Here, as described above, when Si is used as the semi-insulating substrate and InSb is used as the semiconductor film, the resistance value ratio between the semi-insulating substrate and the semiconductor film is small, and the output voltage electrode Is disposed in the vicinity of the input voltage electrode and the ground connection electrode, the current that should flow through the semiconductor film flows through the semi-insulating substrate and a leak current is generated. For this reason, the initial value of the voltage value (hereinafter referred to as “middle point voltage”) of the detection voltage signal obtained from the connection point (middle point) of the magnetoresistive element is a design value based on the premise that no leakage current occurs. The problem of misalignment occurs. Hereinafter, this problem is referred to as “midpoint voltage deviation” becoming large. Furthermore, since the resistance temperature characteristics of the semi-insulating substrate and the resistance temperature characteristics of the semiconductor film are different, there is a problem that the midpoint voltage varies with temperature.

  Therefore, conventionally, in order to solve the problem that the “midpoint voltage deviation” becomes large, in Patent Document 1, the specific resistance and thickness of the Si substrate which is a semi-insulating substrate are regulated, or characteristics different from those of the semi-insulating substrate. By providing this layer or by providing a groove in the semi-insulating substrate, the flow of leak current to the semi-insulating substrate is prevented.

Further, in order to solve the problem relating to the temperature characteristics of the midpoint voltage, in Patent Document 2, impurities are intentionally doped into the semiconductor film so that the change in resistance value due to the temperature of the semiconductor film is reduced.
Japanese Patent Laid-Open No. 9-162459 JP 2005-327859 A

  However, in the configurations and methods shown in Patent Documents 1 and 2, a new layer is inserted into the semi-insulating substrate, physical processing is performed on the semi-insulating substrate, or impurities are doped during the formation of the semiconductor film. Therefore, there arises a problem that the magnetic detection circuit element as a whole cannot be formed easily or cannot be formed unless it goes through a complicated process.

  Accordingly, an object of the present invention is to realize a magnetic detection circuit element capable of reducing the midpoint voltage deviation and improving the temperature characteristics of the midpoint voltage using a simple structure and manufacturing method.

  In the magnetic detection circuit element of the present invention, a plurality of magnetoresistive elements, connection electrodes, input voltage electrodes, ground connection electrodes, and output voltage electrodes are formed on one main surface of a semi-insulating substrate. . The resistance value of the magnetoresistive element changes according to the change of the magnetic flux density. The connection electrode forms a series circuit of the plurality of magnetoresistive elements. The input voltage electrode applies a detection input voltage to the series circuit via the connection electrode. The ground connection electrode connects the series circuit to the ground via the connection electrode. The output voltage electrode is connected to a connection point between the plurality of magnetoresistive elements, and outputs a detection voltage based on the voltage division by the plurality of magnetoresistive elements. The magnetic detection circuit element according to the present invention includes two input electrodes, a ground connection electrode, and an output voltage electrode adjacent to each other on one main surface of the semi-insulating substrate. A correction electrode that is electrically connected to any of an input voltage electrode, a ground connection electrode, and an output voltage electrode different from the electrodes is provided. At this time, the correction electrode is provided in such a position and shape that a predetermined current flows between the correction electrode and one of the two electrodes through the semi-insulating substrate by applying the detection input voltage. .

  In this configuration, the correction electrode has the same potential as any of these electrodes by connecting the correction electrode to the input voltage electrode, the ground connection electrode, and the output voltage electrode. By newly forming such a correction electrode at a predetermined position on the semi-insulating substrate, the ground between the input voltage electrode and the output voltage electrode, which has not existed before the formation of the correction electrode, or the ground A new leakage current (leak resistance) between the connection electrode and the output voltage electrode is intentionally generated. In this way, by adding the leakage current due to the formation of the correction electrode in addition to the leakage current generated before the formation of the correction electrode, the influence on the midpoint voltage deviation is changed by the entire leakage current. Here, the correction electrode having a shape that offsets the influence on the midpoint voltage deviation caused by the leak electrode before the correction electrode is formed by using the influence on the midpoint voltage deviation caused by the leak current based on the formation of the correction electrode By using, the midpoint voltage deviation is reduced. Furthermore, since the leak currents are canceled out, the temperature characteristic of the midpoint voltage due to the difference in resistance temperature characteristics between the semi-insulating substrate and the semiconductor film is stabilized. At this time, the correction electrode can be formed at the same time as the patterning of the other electrodes, so that it is easy to form.

  Further, the correction electrode of the magnetic detection circuit element of the present invention is connected to the input voltage electrode, the ground connection electrode, and the output voltage electrode at a position separated from one main surface of the semi-insulating substrate. Has been.

  In this configuration, since the connection conductor for the correction electrode is formed on a surface other than the one main surface of the semi-insulating substrate, generation of a new leakage current due to the connection conductor is prevented.

  A magnetic sensor according to the present invention includes the above-described magnetic detection circuit element, a housing, and a connection conductor. The housing holds the magnetic detection circuit element and the permanent magnet so that the magnetic detection circuit element is on the detected body side with respect to the permanent magnet and one main surface of the magnetic detection circuit element is on the detected body side. The connection conductor is provided in the housing and is connected to any one of the input voltage electrode, the output voltage electrode, and the ground connection electrode of the magnetic detection circuit element. In the magnetic detection circuit element of the present invention, the correction electrode is connected to any one of the input voltage electrode, the output voltage electrode, and the ground connection electrode by the connection conductor.

  In this configuration, when the magnetic detection circuit element described above is incorporated into the magnetic sensor, the connection between the correction electrode and the correction electrode with the input voltage electrode, the output voltage electrode, and the ground connection electrode is originally connected to the magnetic sensor. This is done by the connecting conductor provided. This eliminates the need to newly provide an electrode pattern for connection to the correction electrode. Further, it is possible to prevent further leakage current from being generated by providing an electrode pattern for connection to the correction electrode.

  According to the present invention, it is possible to realize a magnetic detection circuit element having a simple structure and capable of reducing the midpoint voltage deviation and suppressing changes in the midpoint voltage due to temperature without using a complicated manufacturing process.

  A magnetic detection circuit element and a magnetic sensor according to a first embodiment of the present invention will be described with reference to the drawings.

  FIG. 1A is a plan view showing the configuration of the magnetic detection circuit element 11 of this embodiment, and FIG. 1B is an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 11. In addition, the circuit part which consists of a dotted line shown to FIG. 1 (A), (B) does not represent the thing in which a tangible member like a discrete component or an electrode pattern was actually installed, but a magnetic detection circuit element 11 indicates that there is a function represented by a dotted line.

  The magnetic detection circuit element 11 includes a semi-insulating substrate 12 having a predetermined thickness with Si, GaAs or the like as a base material. Note that the semi-insulating substrate herein refers to a semiconductor substrate that exhibits high resistance (specific resistance is several MΩ) in a substrate that does not contain impurities. On one main surface (corresponding to “one main surface” of the present invention) of the semi-insulating substrate 12, semiconductor films 13A and 13B made of InSb, GaAs, NiSb, InAs or the like are formed. The semiconductor films 13A and 13B are formed in a long shape in a plan view, and are arranged so that the long direction is parallel. On the surfaces of the semiconductor films 13A and 13B, short-circuit electrodes made of a conductive material are formed in a predetermined interval pattern along the longitudinal direction. The ratio with which the resistance value changes according to the sensitivity to the magnetic flux density of the semiconductor films 13A and 13B, that is, the amount of change in the magnetic flux density due to the passage of the subject, is set by this short-circuit electrode formation pattern. The magnetoresistive elements MR1 and MR2 are constituted by the semiconductor films 13A and 13B on which the short-circuit electrodes are thus formed. In the following description, a semiconductor film with a short-circuit electrode is simply treated as a semiconductor film unless otherwise specified.

  The input voltage electrode 14, the ground connection electrode 15, and the output voltage electrode 16 are arranged at one end of the semi-insulating substrate 12 (the left end as viewed in FIG. 1A) along the longitudinal direction of the semiconductor films 13 </ b> A and 13 </ b> B. ) To the ground connection electrode 15, the input voltage electrode 14, and the output voltage electrode 16 in this order.

  The input voltage electrode 14 is connected to one end in the longitudinal direction of the semiconductor film 13A by a connection electrode 17 made of a conductive material. The ground connection electrode 15 is connected to one end in the longitudinal direction of the semiconductor film 13 </ b> B by the connection electrode 17. The output voltage electrode 16 is connected to the other end of the semiconductor film 13A and the semiconductor film 13B in the longitudinal direction by the connection electrode 17.

  With this configuration, the magnetic detection circuit element 11 includes the magnetoresistive element MR1 and the magnetoresistive element MR2, as shown by the solid line in FIG. 1B, the input voltage electrode 14 (Vin) and the ground. A circuit configuration is realized in which the connection points of the magnetoresistive elements MR1 and MR2 are connected to the output voltage electrode 16 (Vout) in series with the connection electrode 15 (GND). When a DC voltage of, for example, 5.0 V is applied to the input voltage electrode 14 of the magnetic detection circuit element 11 having such a configuration, the output voltage electrode 16 ideally causes the magnetoresistive element MR1 and the magnetoresistive element MR2. A DC voltage having a voltage value corresponding to the voltage division ratio is output.

  However, as shown in the prior art described above, a leak current flows between adjacent electrodes of the input voltage electrode 14, the ground connection electrode 15, and the output voltage electrode 16. That is, as shown by Rr1 and Rr2 in FIG. 1, the circuit configuration is such that a leak resistor is connected between adjacent electrodes. Accordingly, in terms of an equivalent circuit, as shown in the circuit portion to which the leakage resistances Rr1 and Rr2 in the solid line portion and the dotted line portion in FIG. 1B are connected, the input voltage electrode 14 (Vin) and the ground connection electrode 15 (GND) is connected to the leak resistor Rr1, and a parallel circuit of the magnetoresistive element MR1 and the leak resistor Rr2 is provided between the input voltage electrode 14 (Vin) and the output voltage electrode 16 (Vout). The magnetoresistive element MR2 is connected between the output voltage electrode 16 (Vout) and the ground connection electrode 15 (GND).

  Therefore, in the present embodiment, a correction electrode 16 ′ that is electrically connected to the output voltage electrode 16 is disposed between the adjacent input voltage electrode 14 and the ground connection electrode 15. The correction electrode 16 ′ is connected to the output voltage electrode 16 by a connection conductor 18 formed in a region other than one main surface of the semi-insulating substrate 12. As a result, a new leak resistance Rc1 is inserted between the correction electrode 16 ′ and the input voltage electrode 14, and a new leak resistance Rc2 is inserted between the correction electrode 16 ′ and the ground connection electrode 15. Circuit configuration.

  That is, as shown in FIG. 1B, a parallel circuit of a magnetoresistive element MR1 and leak resistors Rr2 and Rc1 is connected between the input voltage electrode 14 (Vin) and the output voltage electrode 16 (Vout). A parallel circuit of the magnetoresistive element MR2 and the leakage resistor Rc2 is connected between the output voltage electrode 16 (Vout) and the ground connection electrode 15 (GND), and the input voltage electrode 14 (Vin) and the ground. A leakage resistor Rr1 is connected to the connection electrode 15 (GND).

  Here, the shape and position of the correction electrode 16 ′ are set so that the voltage dividing ratio between the parallel circuit of the leakage resistors Rc1 and Rr2 and the leakage resistance Rc2 matches the voltage dividing ratio with the magnetoresistive elements MR1 and MR2. Set. For example, if the resistance values of the magnetoresistive elements MR1 and MR2 are the same, the correction electrode 16 is set so that the combined resistance value of the parallel circuit of the leak resistances Rc1 and Rr2 matches the resistance value of the leak resistance Rc2. Set the shape and position of '. The formation position is set based on the distance between the correction electrode 16 ′ and other electrodes, particularly the input voltage electrode 14 and the ground connection electrode 15 that determine the leakage resistance.

  With such a configuration, it is possible to suppress and reduce the midpoint voltage deviation caused by the leak resistance Rr2 caused by the electrode pattern in the state where the correction electrode 16 'is not formed. At this time, the series combined resistance value of the parallel circuit of the leak resistors Rc1 and Rr2 and the leak resistor Rc2 is significantly larger than the series combined resistance value of the magnetoresistive elements MR1 and MR2 (for example, 100 times or more). Good. As a result, the current due to the DC voltage applied from the input voltage electrode 14 mainly flows to the magnetoresistive elements MR1 and MR2, but does not flow to the parallel circuit of the leak resistors Rc1 and Rr2 and the leak resistor Rc2. Therefore, it is possible to detect a change in magnetic flux density due to the passage of the detection object without reducing the detection sensitivity.

  Thus, by using the configuration of the present embodiment, it is possible to realize a magnetic detection circuit element that can suppress the midpoint voltage deviation to a small level and suppress the temperature change of the midpoint voltage. At this time, detection can be performed without lowering the detection sensitivity by appropriately setting the resistance value of each leak resistance by the correction electrode. Further, the correction electrode can be formed of the same material as the input voltage electrode, the output voltage electrode, the ground connection electrode, and the connection electrode, and is formed of an electrode pattern formed on one main surface of the semi-insulating substrate 12. Since it can be regarded as a part, it can be patterned simultaneously with the input voltage electrode, the output voltage electrode, the ground connection electrode, and the connection electrode, and can be formed with a simple structure and a simple manufacturing method.

Such a magnetic detection circuit element 11 is mounted on a magnetic sensor 1 as shown in FIG.
FIG. 2 is a side view showing the main configuration of the magnetic sensor 1 and is shown in a sectional view for easy understanding of the structure.

  The magnetic sensor 1 includes a substantially rectangular parallelepiped housing 2 made of an insulating material, and a permanent magnet 3 is installed in the housing 2. The above-described magnetic detection circuit element 11 is disposed on the detection target side of the permanent magnet 3. The magnetic detection circuit element 11 is arranged so that the surface (one main surface) on which the magnetoresistive elements MR1 and MR2 are formed is opposite to the permanent magnet 3 with respect to the semi-insulating substrate 12. An input voltage electrode, an output voltage electrode, and a ground connection electrode (not shown in FIG. 2) of the magnetic detection circuit element 11 are connected to the external connection terminal 5 by a connection conductor 6.

  An insulating sheet 7 is provided on the upper surface of one main surface of the magnetic detection circuit element 11 to electrically insulate each part on the main surface of the magnetic detection circuit element 11 from the cover 4. The cover 4 has a shape that covers each member constituting the magnetic sensor 1.

  Here, the connection conductor 18 that connects the correction electrode 16 ′ of the magnetic detection circuit element 11 and the output voltage electrode 16 is replaced with the connection conductor 6 that constitutes the magnetic sensor 1 and a part of the external connection terminal 5. Use to generate. With such a configuration, it is not necessary to form the connection conductor 18 on one main surface of the magnetic detection circuit element 11, and generation of a new leak resistance due to the connection conductor 18 can be prevented. Further, by using the connection conductor 6 of the magnetic sensor 1 and the external connection terminal 5, the connection conductor 18 for connecting the correction electrode 16 ′ and the output voltage electrode 16 is originally formed by the components necessary for the magnetic sensor 1. Since it can be formed, it can be easily designed and formed.

Next, a magnetic detection circuit element according to a second embodiment will be described with reference to the drawings.
FIG. 3A is a plan view showing the configuration of the magnetic detection circuit element 21 of the present embodiment, and FIG. 3B is an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 21. It is.
The magnetic detection circuit element 21 of this embodiment has two output voltages, and the basic configuration is similar to that of the first embodiment in which there is one output voltage.

  The magnetic detection circuit element 21 includes a semi-insulating substrate 22 similar to the semi-insulating substrate 12 of the first embodiment. Semiconductor films 23 </ b> A to 23 </ b> D are formed on one main surface of the semi-insulating substrate 22. The semiconductor films 23 </ b> A to 23 </ b> D are formed in a long shape in a plan view, and are arranged so that the long direction is parallel. Short-circuit electrodes are formed on the surfaces of the semiconductor films 23A to 23D in a predetermined interval pattern along the longitudinal direction. The magnetoresistive elements MR1 to MR4 are configured by the semiconductor films 23A to 23D in which the short-circuit electrodes are thus formed.

  Outside the formation region of the semiconductor films 23A to 23D, on one end side in the arrangement direction (upper side in FIG. 3A), along the longitudinal direction of the semiconductor films 23A to 23D, the input voltage electrode 24, An output voltage electrode 261 and an output voltage electrode 263 are formed in an array. Further, outside the formation region of the semiconductor films 23A to 23D, on the other end side in the arrangement direction (the lower side in FIG. 3A), an output voltage electrode along the longitudinal direction of the semiconductor films 23A to 23D. 262, an output voltage electrode 264, and a ground connection electrode 25 are arranged. At this time, the input voltage electrode 24 and the output voltage electrode 262 are arranged to face each other with the longitudinal direction of the semiconductor films 23 </ b> A to 23 </ b> D as the symmetry reference.

  The input voltage electrode 24 is connected to one end of the semiconductor films 23A and 23B in the longitudinal direction by the connection electrode 271. The output voltage electrode 261 is connected to the other end in the longitudinal direction of the semiconductor film 23 </ b> A by the connection electrode 271. The output voltage electrode 263 is connected to the other end in the longitudinal direction of the semiconductor film 23 </ b> B by the connection electrode 271.

  The output voltage electrode 262 is connected to one end in the longitudinal direction of the semiconductor film 23 </ b> C by the connection electrode 272. The output voltage electrode 264 is connected to one end of the semiconductor film 23D in the longitudinal direction by the connection electrode 272. The ground connection electrode 25 is connected to the other end of the semiconductor films 23C and 23D in the longitudinal direction by the connection electrode 272.

  Furthermore, the output voltage electrode 261 and the output voltage electrode 262 are electrically connected by an electrode pattern and a connection conductor (not shown), and both the output voltage electrode 263 and the output voltage electrode 264 are illustrated. It is electrically connected by no electrode pattern or connection conductor. For example, the connection conductor can be realized by a connection conductor or the like constituting the magnetic sensor as shown in the first embodiment. The electrode pattern can be realized by forming an insulating film on one main surface of the semi-insulating substrate 22 on which these semiconductor films and the like are formed and forming the electrode pattern on the insulating film.

  With this configuration, the magnetic detection circuit element 21 includes the magnetoresistive element MR1 and the magnetoresistive element MR3, the input voltage electrode 24 (Vin), and the ground as shown by the solid line in FIG. A circuit configuration is realized in which the connection points of the magnetoresistive elements MR1 and MR3 are connected to the output voltage electrodes 261 and 262 (Vout-A) in series with the connection electrode 25 (GND). At the same time, as shown by the solid line in FIG. 2B, the magnetic detection circuit element 21 includes the magnetoresistive element MR2 and the magnetoresistive element MR4, the input voltage electrode 24 (Vin) and the ground connection electrode 25 ( The circuit configuration is realized in which the connection points of the magnetoresistive elements MR2 and MR4 are connected to the output voltage electrodes 263 and 264 (Vout). When a DC voltage such as 5.0 V is applied to the input voltage electrode 24 (Vin) of the magnetic detection circuit element 21 having such a configuration, ideally, the output voltage electrodes 261 and 262 (Vout-A) are magnetized. A DC voltage having a voltage value corresponding to the voltage dividing ratio of the resistive element MR1 and the magnetoresistive element MR3 is output, and the voltage dividing ratio of the magnetoresistive element MR2 and the magnetoresistive element MR4 from the output voltage electrodes 263, 264 (Vout-B). A DC voltage having a voltage value corresponding to the output is output.

  However, a leakage current flows between adjacent electrodes of the input voltage electrode 24, the ground connection electrode 25, and the output voltage electrodes 261 to 264. That is, as shown by Rr1 to Rr4 in FIG. 1, the circuit configuration is such that a leak resistor is connected between adjacent electrodes.

  Thereby, in terms of an equivalent circuit, as shown in the circuit portion to which the leak resistances Rr1 to Rr4 (Rr1 and Rr2 are considered to be connected) in the solid line portion and the dotted line portion in FIG. Between the input voltage electrode 24 (Vin) and the output voltage electrodes 261, 262 (Vout-A), leakage resistances Rr1, Rr2 are connected in parallel with the magnetoresistive element MR1, and the output voltage electrodes 261, 262 (Vout− A magnetoresistive element MR2 is connected between A) and the ground connection electrode 25 (GND). Further, the magnetoresistive element MR3 is connected between the input voltage electrode 24 (Vin) and the output voltage electrodes 263, 264 (Vout-B), and is connected to the output voltage electrodes 263, 264 (Vout-B) and the ground. The leakage resistors Rr2 and Rr4 are connected in parallel with the magnetoresistive element MR4 between the electrode 25 (GND).

  Therefore, in the present embodiment, a correction electrode 266 ′ that is electrically connected to one of the output voltage electrodes 263 and 264 is further disposed between the adjacent input voltage electrode 24 and the output voltage electrode 261. To do. The correction electrode 266 ′ is connected to one of the output voltage electrodes 263, 264 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 22. As a result, a new leak resistance Rc3 is inserted between the correction electrode 266 ′ and the input voltage electrode 24, and the leak resistance Rr1 existing between the input voltage electrode 24 and the output voltage electrode 261 is reduced. The circuit configuration is eliminated.

  Further, in the present embodiment, a correction electrode 265 ′ that is electrically connected to any one of the output voltage electrodes 261 and 262 is disposed between the adjacent ground connection electrode 25 and the output voltage electrode 264. To do. The correction electrode 265 ′ is connected to one of the output voltage electrodes 261 and 262 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 22. As a result, a new leak resistance Rc4 is inserted between the correction electrode 265 ′ and the ground connection electrode 25, and the leak resistance Rr2 existing between the ground connection electrode 25 and the output voltage electrode 264 is reduced. The circuit configuration is eliminated.

  That is, as shown in FIG. 3B, a parallel circuit of a magnetoresistive element MR1 and a leak resistor Rr3 between the input voltage electrode 24 (Vin) and the output voltage electrodes 261, 262 (Vout-A). Are connected, and a parallel circuit of the magnetoresistive element MR3 and the leakage resistance Rc4 is connected between the output voltage electrodes 261 and 262 (Vout-A) and the ground connection electrode 25 (GND). Further, a parallel circuit of the magnetoresistive element MR2 and the leakage resistor Rc3 is connected between the input voltage electrode 24 (Vin) and the output voltage electrodes 263, 264 (Vout-B), and the output voltage electrode 263, A parallel circuit of a magnetoresistive element MR4 and a leak resistor Rr4 is connected between H.264 (Vout-B) and the ground connection electrode 25 (GND).

  Here, the shape and position of the correction electrode 265 ′ are set so that the voltage dividing ratio of the leakage resistors Rr3, Rc4 matches the voltage dividing ratio of the magnetoresistive elements MR1, MR3, and the magnetoresistive elements MR2, MR2 are set. The shape and formation position of the correction electrode 266 ′ are set so that the voltage division ratio of the leak resistors Rc3, Rr4 matches the voltage division ratio of MR4. For example, if the resistance values of the magnetoresistive elements MR1 to MR4 match, the resistance values of the leak resistances Rc3, Rc4, Rr3, and Rr4 are set to be the same. As a result, the midpoint voltage deviation caused by the leakage resistances Rr1 to Rr4 caused by the electrode pattern in the state where the correction electrodes 265 'and 266' are not formed can be suppressed and reduced. At this time, the series combined resistance value of the leak resistors Rr3 and Rc4 and the series combined resistance value of the leak resistors Rc3 and Rr4 are the series combined resistance value of the magnetoresistive elements MR1 and MR3 and the series combined resistance of the magnetoresistive elements MR2 and MR4. It is preferable that the value be significantly larger than the value (for example, 100 times or more). As a result, the current due to the DC voltage applied from the input voltage electrode 24 mainly flows through the series circuit of the magnetoresistive elements MR1 and MR3 and the series circuit of the magnetoresistive elements MR2 and MR4. Therefore, it is possible to detect a change in magnetic flux density due to the passage of the detection object without reducing the detection sensitivity.

  Thus, even when the configuration of the present embodiment is used, a magnetic detection circuit element that can suppress the midpoint voltage deviation and suppress the temperature change of the midpoint voltage, as in the first embodiment described above. Can be realized.

FIG. 4 is a diagram illustrating temperature characteristics of the detected output voltage before and after using the configuration of the present embodiment.
As shown in FIG. 4, if the configuration of this embodiment is not used, the output voltage temperature change of the output voltage electrodes 261 and 262 (Vout-A) is about 11 mV between about −20 ° C. and about 100 ° C. However, by using the configuration of the present embodiment, the voltage can be reduced to about 5 mV. Also, the deviation of the initial voltage value of the output voltage electrodes 263 and 264 (Vout-B) can be improved by about 3 mV at about 30 ° C.

Next, the configuration of the magnetic detection circuit element 31 according to the third embodiment will be described.
FIG. 5A is a plan view showing the configuration of the magnetic detection circuit element 31 of the present embodiment, and FIG. 5B is an equivalent circuit for explaining the concept of the magnetic detection circuit element 31. FIG.

  The magnetic detection circuit element 31 of the present embodiment is the same as the magnetic detection circuit element 21 of the second embodiment except for the configuration of the correction electrodes 34 ′ and 35 ′. Therefore, only the portion related to the correction electrodes 34 'and 35' will be described.

  In the present embodiment, a correction electrode 35 ′ that is electrically connected to the ground connection electrode 25 is disposed between the adjacent input voltage electrode 24 and the output voltage electrode 261. The correction electrode 35 ′ is connected to the ground connection electrode 25 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 32. As a result, a new leak resistance Rc5 is inserted between the correction electrode 35 ′ and the output voltage electrode 261, and the leak resistance Rr1 existing between the input voltage electrode 24 and the output voltage electrode 261 is reduced. The circuit configuration is eliminated.

  In the present embodiment, a correction electrode 34 ′ that is electrically connected to the input voltage electrode 24 is further disposed between the adjacent ground connection electrode 25 and the output voltage electrode 264. The correction electrode 34 ′ is connected to the input voltage electrode 24 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 22. As a result, a new leak resistance Rc6 is inserted between the correction electrode 34 ′ and the output voltage electrode 264, and the leak resistance Rr2 existing between the ground connection electrode 25 and the output voltage electrode 264 is reduced. The circuit configuration is eliminated.

  That is, as shown in FIG. 5B, a parallel circuit of a magnetoresistive element MR1 and a leak resistor Rr3 between the input voltage electrode 24 (Vin) and the output voltage electrodes 261, 262 (Vout-A). Are connected, and a parallel circuit of the magnetoresistive element MR3 and the leak resistor Rc5 is connected between the output voltage electrodes 261 and 262 (Vout-A) and the ground connection electrode 25 (GND). Further, a parallel circuit of the magnetoresistive element MR2 and the leak resistor Rc6 is connected between the input voltage electrode 24 (Vin) and the output voltage electrodes 263, 264 (Vout-B), and the output voltage electrode 263, A parallel circuit of a magnetoresistive element MR4 and a leak resistor Rr4 is connected between H.264 (Vout-B) and the ground connection electrode 25 (GND).

  Here, the shape and position of the correction electrode 35 ′ are set so that the voltage dividing ratio of the leakage resistors Rr3, Rc5 matches the voltage dividing ratio of the magnetoresistive elements MR1, MR3, and the magnetoresistive elements MR2, MR2 are set. The shape and formation position of the correction electrode 34 ′ are set so that the voltage division ratio of the leak resistors Rc6 and Rr4 matches the voltage division ratio of MR4. For example, if the resistance values of the magnetoresistive elements MR1 to MR4 match, the resistance values of the leak resistors Rc5, Rc6, Rr3, and Rr4 are set to be the same. Thereby, it is possible to suppress and reduce the midpoint voltage deviation caused by the leakage resistances Rr1 to Rr4 caused by the electrode pattern in the state where the correction electrodes 34 'and 35' are not formed. At this time, the series combined resistance value of the leak resistors Rr3 and Rc5 and the series combined resistance value of the leak resistors Rc6 and Rr4 are the series combined resistance value of the magnetoresistive elements MR1 and MR3 and the series combined resistance of the magnetoresistive elements MR2 and MR4. It is preferable that the value be significantly larger than the value (for example, 100 times or more). As a result, the current due to the DC voltage applied from the input voltage electrode 24 mainly flows through the series circuit of the magnetoresistive elements MR1 and MR3 and the series circuit of the magnetoresistive elements MR2 and MR4. Therefore, it is possible to detect a change in magnetic flux density due to the passage of the detection object without reducing the detection sensitivity.

  Thus, even when the configuration of the present embodiment is used, a magnetic detection circuit element that can suppress the midpoint voltage deviation and suppress the temperature change of the midpoint voltage, as in the first embodiment described above. Can be realized.

Next, a magnetic detection circuit element according to a fourth embodiment will be described with reference to the drawings.
FIG. 6A is a plan view showing the configuration of the magnetic detection circuit element 41 of the present embodiment, and FIG. 6B is an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 41. It is.

  The magnetic detection circuit element 41 of the present embodiment is different from the second and third embodiments in the arrangement pattern of the input voltage electrode, the output voltage electrode, the ground connection electrode, and the correction electrode. The formation patterns of the semiconductor films 43A to 43D constituting the elements MR1 to MR4 are the same.

  Outside the formation region of the semiconductor films 43A to 43D, on one end side in the arrangement direction (upper side in FIG. 6A), along the longitudinal direction of the semiconductor films 43A to 43D, the input voltage electrode 44, An output voltage electrode 461 and an output voltage electrode 463 are arranged. Further, outside the formation region of the semiconductor films 43A to 43D, on the other end side in the arrangement direction (the lower side in FIG. 6A), the electrodes for ground connection are provided along the longitudinal direction of the semiconductor films 43A to 43D. 45, an output voltage electrode 464 and an output voltage electrode 462 are arranged. At this time, the input voltage electrode 44 and the ground connection electrode 45 are arranged to face each other with the longitudinal direction of the semiconductor films 43 </ b> A to 43 </ b> D as the symmetry reference.

  The input voltage electrode 44 is connected to one end of the semiconductor films 43A and 43B in the longitudinal direction by the connection electrode 471. The output voltage electrode 461 is connected to the other end in the longitudinal direction of the semiconductor film 43 </ b> A by the connection electrode 471. The output voltage electrode 463 is connected to the other end in the longitudinal direction of the semiconductor film 43B by the connection electrode 471.

  The ground connection electrode 45 is connected to one end of the semiconductor films 43C and 43D in the longitudinal direction by the connection electrode 472. The output voltage electrode 464 is connected to the other end in the longitudinal direction of the semiconductor film 43D by the connection electrode 472. The output voltage electrode 462 is connected to one end of the semiconductor film 43C in the longitudinal direction by the connection electrode 472.

  Further, the output voltage electrode 461 and the output voltage electrode 462 are electrically connected by an electrode pattern and a connection conductor (not shown), and the output voltage electrode 463 and the output voltage electrode 464 are not shown. They are electrically connected by electrode patterns and connecting conductors. For example, the connection conductor can be realized by a connection conductor or the like constituting the magnetic sensor as shown in the first embodiment. The electrode pattern can be realized by forming an insulating film on one main surface of the semi-insulating substrate 42 on which the semiconductor film or the like is formed and forming the electrode pattern on the insulating film.

  Further, a correction electrode 44 ′ electrically connected to the input voltage electrode 44 is disposed between the adjacent output voltage electrodes 461 and 463. The correction electrode 44 ′ is connected to the input voltage electrode 44 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 42. As a result, a new leak resistance Rc7 is inserted between the correction electrode 44 ′ and the output voltage electrode 461, and a new leak resistance Rc8 is inserted between the correction electrode 44 ′ and the output voltage electrode 463. Inserted.

  Further, a correction electrode 45 ′ electrically connected to the ground connection electrode 45 is disposed between the adjacent output voltage electrodes 462 and 464. The correction electrode 45 ′ is connected to the input voltage electrode 45 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 42. As a result, a new leak resistance Rc9 is inserted between the correction electrode 45 ′ and the output voltage electrode 462, and a new leak resistance Rc10 is added between the correction electrode 45 ′ and the output voltage electrode 464. Inserted.

  As a result, as shown in FIG. 6B, the magnetoresistive element MR1 and the leakage resistance Rr1 are interposed between the input voltage electrodes 44 and 44 ′ (Vin) and the output voltage electrodes 461 and 462 (Vout-A). Are connected between the output voltage electrodes 461 and 462 (Vout-A) and the ground connection electrodes 45 and 45 ′ (GND), and the magnetoresistive element MR3 and the leak resistor Rc9. A parallel circuit is connected. Further, a parallel circuit of the magnetoresistive element MR2 and the leak resistor Rc8 is connected between the input voltage electrodes 44, 44 ′ (Vin) and the output voltage electrodes 463, 464 (Vout-B), and the output voltage electrodes A parallel circuit of the magnetoresistive element MR4, the leak resistor Rr2, and the leak resistor Rc10 is connected between the electrodes 463 and 464 (Vout-B) and the ground connection electrodes 45 and 45 ′ (GND). Further, a leakage resistance Rr5 that does not affect the midpoint voltage characteristics is connected between the input voltage electrodes 44 and 44 'and the ground connection electrodes 45 and 45'.

  Here, with respect to the voltage dividing ratio between the magnetoresistive elements MR1 and MR3, the voltage dividing ratio between the parallel circuit of the leakage resistance Rr1 and the leakage resistance Rc7 and the leakage resistance Rc9 coincides, and the voltage dividing ratio between the magnetoresistive elements MR2 and MR4. The shape and the formation position of the correction electrodes 44 ′ and 45 ′ are set so that the voltage dividing ratio of the parallel circuit of the leak resistor Rc8 and the leak resistors Rr2 and Rc10 matches. Thereby, it is possible to suppress and reduce the midpoint voltage deviation caused by the leakage resistances Rr1 and Rr2 caused by the electrode pattern in the state where the correction electrodes 44 'and 45' are not formed. At this time, the series combined resistance value of the parallel circuit of the leak resistors Rr1 and Rc7 and the leak resistor Rc9 and the series combined resistance value of the parallel circuit of the leak resistor Rc8 and the leak resistors Rr2 and Rc10 are the magnetoresistive elements MR1, MR3. It is preferable to make the value significantly larger (for example, 100 times or more) than the series combined resistance value of the magnetoresistive elements MR2 and MR4. As a result, the current due to the DC voltage applied from the input voltage electrode 44 mainly flows through the series circuit of the magnetoresistive elements MR1 and MR3 and the series circuit of the magnetoresistive elements MR2 and MR4. Therefore, it is possible to detect a change in magnetic flux density due to the passage of the detection object without reducing the detection sensitivity.

  As described above, even when the configuration of the present embodiment is used, a magnetic detection circuit element that can suppress the midpoint voltage deviation to a small level and suppress the temperature change of the midpoint voltage is realized as in the above-described embodiments. be able to.

Next, a magnetic detection circuit element according to a fifth embodiment will be described with reference to the drawings.
FIG. 7A is a plan view showing the configuration of the magnetic detection circuit element 51 of the present embodiment, and FIG. 7B is an equivalent circuit for explaining the concept of the magnetic detection circuit element 51. FIG.

  The magnetic detection circuit element 51 of the present embodiment is the same as the magnetic detection circuit element 41 of the fourth embodiment except for the configuration of the correction electrodes 54 ′ and 55 ′. Therefore, only the portion related to the correction electrodes 54 'and 55' will be described.

  In the present embodiment, a correction electrode 55 ′ that is electrically connected to the ground connection electrode 45 is disposed between the adjacent output voltage electrodes 461 and 463. The correction electrode 55 ′ is connected to the ground connection electrode 45 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 42. As a result, a new leak resistance Rc11 is inserted between the correction electrode 55 'and the output voltage electrode 461. Further, a new leak resistor Rc12 is inserted between the correction electrode 55 'and the output voltage electrode 463.

  In this embodiment, a correction electrode 54 ′ that is electrically connected to the input voltage electrode 44 is further disposed between the adjacent output voltage electrodes 462 and 464. The correction electrode 54 ′ is connected to the input voltage electrode 44 by a connection conductor formed in a region other than one main surface of the semi-insulating substrate 52. As a result, a new leak resistor Rc13 is inserted between the correction electrode 54 'and the output voltage electrode 464. Further, a new leak resistance Rc14 is inserted between the correction electrode 54 'and the output voltage electrode 462.

  That is, as shown in FIG. 7B, between the input voltage electrode 44 (Vin) and the output voltage electrodes 461, 462 (Vout-A), the magnetoresistive element MR1 and the leakage resistances Rr1, Rc14 A configuration in which a parallel circuit is connected, and a parallel circuit of a magnetoresistive element MR3 and a leakage resistor Rc11 is connected between the output voltage electrodes 461 and 462 (Vout-A) and the ground connection electrode 45 (GND). Become. Further, a parallel circuit of the magnetoresistive element MR2 and the leakage resistor Rc13 is connected between the input voltage electrode 44 (Vin) and the output voltage electrodes 463, 464 (Vout-B), and the output voltage electrode 463, A parallel circuit of a magnetoresistive element MR4 and leak resistors Rr2 and Rc12 is connected between 464 (Vout-B) and the ground connection electrode 45 (GND).

  Here, with respect to the voltage dividing ratio of the magnetoresistive elements MR1 and MR3, the parallel circuit of the leak resistors Rr1 and Rc14 and the voltage dividing ratio of the leak resistor Rc11 coincide with each other, and with respect to the voltage dividing ratio of the magnetoresistive elements MR2 and MR4, The shapes and formation positions of the correction electrodes 54 ′ and 55 ′ are set so that the voltage dividing ratio of the parallel circuit of the resistor Rc13 and the leak resistors Rr2 and Rc12 matches. Thereby, it is possible to suppress and reduce the midpoint voltage deviation caused by the leak resistances Rr1 and Rr2 caused by the electrode pattern in which the correction electrodes 54 'and 55' are not formed. At this time, the series combined resistance value of the parallel circuit of the leak resistors Rr1 and Rc14 and the leak resistor Rc11 and the series combined resistance value of the parallel circuit of the leak resistor Rc13 and the leak resistors Rr2 and Rc12 are the magnetoresistive elements MR1 and MR3. It is preferable to make the value significantly larger (for example, 100 times or more) than the series combined resistance value of the magnetoresistive elements MR2 and MR4. As a result, the current due to the DC voltage applied from the input voltage electrode 44 mainly flows through the series circuit of the magnetoresistive elements MR1 and MR3 and the series circuit of the magnetoresistive elements MR2 and MR4. Therefore, it is possible to detect a change in magnetic flux density due to the passage of the detection object without reducing the detection sensitivity.

  As described above, even when the configuration of the present embodiment is used, a magnetic detection circuit element that can suppress the midpoint voltage deviation to a small level and suppress the temperature change of the midpoint voltage is realized as in the above-described embodiments. be able to.

  In addition to the configuration shown in each of the embodiments described above, the output voltage electrode may be offset so that the potential of the output voltage electrode is affected by the potential of the input voltage electrode or the potential of the ground connection electrode. The above-described operations and effects can be achieved if the correction electrode connected to at least one of the input voltage electrode and the ground connection electrode is formed.

FIG. 2 is a plan view showing the configuration of the magnetic detection circuit element 11 of the first embodiment and an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 11. 1 is a side view showing a main configuration of a magnetic sensor 1. FIG. FIG. 6 is a plan view showing a configuration of a magnetic detection circuit element 21 according to a second embodiment and an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 21. It is the figure which showed the temperature characteristic of the detection output voltage by before and after using the structure of 2nd Embodiment. FIG. 6 is a plan view showing a configuration of a magnetic detection circuit element 31 according to a third embodiment and an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 31. FIG. 6 is a plan view showing a configuration of a magnetic detection circuit element 41 according to a fourth embodiment and an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 41. FIG. 9 is a plan view showing a configuration of a magnetic detection circuit element 51 of a fifth embodiment and an equivalent circuit diagram for explaining the concept of the magnetic detection circuit element 51.

Explanation of symbols

1-magnetic sensor, 2-housing, 3-permanent magnet, 4-cover, 5-terminal for external connection, 6-connection conductor, 7-insulating sheet,
11, 21, 31, 41, 51-magnetic detection circuit element, 12, 22, 42-semi-insulating substrate, 13A, 13B, 23A-23D, 43A-43D-semiconductor film, 14, 24, 44-for input voltage Electrode, 15, 25, 45-ground connection electrode, 16, 261-264, 461-464-output voltage electrode, 17, 271, 272, 471, 472-connection electrode, 18-connection conductor,
16 ', 265', 266 ', 34', 35 ', 44', 45 ', 54', 55'-correction electrodes

Claims (3)

A plurality of magnetoresistive elements whose resistance values change according to a change in magnetic flux density, a connection electrode forming a series circuit of the plurality of magnetoresistive elements, and an input voltage for detection to the series circuit via the connection electrode An input voltage electrode for applying, a ground connection electrode for connecting the series circuit to the ground via the connection electrode, and a connection point between the plurality of magnetoresistive elements, and An output voltage electrode for outputting a detection voltage based on voltage division by a resistive element, and a magnetic detection circuit element formed on one main surface of a semi-insulating substrate,
The input different from the two electrodes between the two electrodes of the input voltage electrode, the ground connection electrode, and the output voltage electrode adjacent to each other on one main surface of the semi-insulating substrate A correction electrode that is electrically connected to any one of the voltage electrode, the ground connection electrode, and the output voltage electrode is selected from the correction electrode and the two electrodes by applying the detection input voltage. A magnetic detection circuit provided in a position and shape so that a predetermined current flows between the heels through the semi-insulating substrate.   The correction electrode is connected to the input voltage electrode, the ground connection electrode, and the output voltage electrode at a position separated from one main surface of the semi-insulating substrate. Item 2. The magnetic detection circuit element according to Item 1. While comprising the magnetic detection circuit element according to claim 2,
A case in which the magnetic detection circuit element is disposed on the detected object side with respect to the permanent magnet so that the one main surface is on the detected object side;
A connection conductor provided in the housing and connected to any one of the input voltage electrode, the output voltage electrode, and the ground connection electrode of the magnetic detection circuit element;
A magnetic sensor that connects the correction electrode to any one of the input voltage electrode, the output voltage electrode, and the ground connection electrode by the connection conductor.

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