JP2020160081A - Three-dimensional magnetic field detector - Google Patents

Abstract

To provide a three-dimensional magnetic field detector which performs three magnetic field detection element functions of an X-axis, a Y-axis, a Z-axis on an integrated circuit chip and is composed of an ultrahigh sensitivity three-dimensional magnetic field detection element of 0.35 mm or less thickness.SOLUTION: On an integrated circuit chip, two magnetic field detection elements are arranged in an X-axis direction and aY-axis direction point symmetrically around an origin point of the integrated circuit chip respectively, a lower part soft magnetic material plate is arranged in a lower part of a magnetic field detection element arrangement surface parallel to a magnetic field detection element arrangement surface and four upper part soft magnetic material plates are arranged in an upper part of four magnetic field detection elements, the lower part soft magnetic material plate and magnetic wires of the four magnetic field detection elements are magnetically connected at an origin point position, magnetosensitive bodies of the four magnetic field detection elements and the four upper part soft magnetic material plates are magnetically connected at an end part opposite the origin point, a Z-axis direction magnetic field is effectively flux concentrated in one of the upper part and the lower part soft magnetic material plates, magnetic-field components in three directions of the X-axis direction, theY-axis direction, and the Z-axis direction are measured, so that a magnetic field vector at the origin point position is detected.SELECTED DRAWING: Figure 10

Description

The present invention realizes the functions of the three magnetic field detection elements of the X-axis, Y-axis, and Z-axis used in the orientation sensor and the like on one substrate, thereby providing the basics such as high sensitivity, low noise, and wide measurement range of the orientation sensor. The present invention relates to a technique that enables a thin, small and high-performance three-dimensional magnetic field detection device by making it possible to reduce the height, length and width of the three-dimensional magnetic field detection element while maintaining the performance.

The azimuth sensor measures a geomagnetic vector by combining three magnetic sensor elements of the X-axis, Y-axis, and Z-axis and an integrated circuit, and calculates the azimuth from the values. It is widely used as a 3D azimuth meter in combination with an acceleration sensor and a vibration gyro sensor in smartphones, tablets, Internet TV remote controls, games, motion capture, etc., but in recent years these devices have become even more sensitive and low. There is a strong demand for miniaturization and thinning along with noise reduction and widening of the measurement range. In particular, as smartphones have become thinner, the height of the azimuth sensor has been reduced from the conventional 1.0 mm to 0.6 mm, which is 40% or more thinner, and the size has been reduced from the conventional 2.0 mm square to 1.5 mm square, which is 50% or more smaller. Is required. Further, regarding noise, it is required to improve the performance 10 times from the conventional 10 mG or less to 1 mG or less.

A Hall element, an MR element, an MI (abbreviation of Magnet-Impedance) element, and a GSR (abbreviation of GHz-Spin-Rotation) element are used as the magnetic field detection element in the azimuth sensor. Usually, three elements, an X-axis element, a Y-axis element, and a Z-axis element, are used to measure the strength of the magnetic field vector components Hx, Hy, and Hz in the X-axis direction, the Y-axis direction, and the Z-axis direction. Make a measurement. In the case of a Hall element, since the magnetic field is detected in the direction perpendicular to the element surface, it is necessary to arrange the Z-axis element on the surface and assemble the X-axis element and the Y-axis element upright on the sensor substrate. On the other hand, since MR elements and MI elements detect a magnetic field parallel to the element surface, it is necessary to arrange the X-axis element and the Y-axis element on the surface and assemble the Z-axis element upright on the sensor substrate. As long as three elements are used, there is a problem that the height of the sensor becomes large.

To solve this problem, Asahi Kasei Co., Ltd. has developed a three-dimensional magnetic field detection element that does not use X-axis elements and Y-axis elements by arranging four Z-axis elements on one substrate using Hall elements. It has been successful and is produced and sold as an orientation sensor. The structure of the three-dimensional magnetic field detection element is such that a pair of ZX1 element and ZX2 element and a pair of ZY1 element and ZY2 element are arranged in a cross shape on a substrate in the X-axis direction and the Y-axis direction, respectively, and magnetic at the center thereof. A thin disk of permalloy, which is a material, is arranged as a magnetic field modifier. This device detects a three-dimensional magnetic field vector by first adding the four outputs of ZX1 element, ZX2 element, ZY1 element, and ZY2 element to the magnetic field in the Z-axis direction, and then detects the magnetic field in the X-axis direction and the Y-axis direction. The magnetic fields of are generated by the permalloy disk in the Z-axis direction, the magnetic field in the X-axis direction is the difference between the outputs of the ZX1 element and the ZX2 element, and the magnetic field in the Y-axis direction is the output of the ZY1 element and the ZY2 element. It is detected by the difference. Since there is no element to stand on the sensor board, the height can be thin and the size can be reduced. A magnetic field detection element that can detect a magnetic field perpendicular to the element surface, such as a Hall element, can easily make the device thinner, but this type of magnetic field detection element, such as a Hall sensor, requires noise of about 10 mG and 1 mG. On the other hand, it had the drawback of being too large, which was a big problem in use.

On the other hand, although it is possible to improve the noise of the MI element to 1 mG or less, when the Z-axis element is assembled upright on the substrate surface, the height of the MI element and the detection sensitivity are contradictory, so the height should be reduced. Was difficult. This is because the MI element is made by winding a detection coil around a magnetic sensor such as an amorphous wire, and a high-frequency pulse current or the like is passed through the magnetic sensor to detect the detection coil voltage proportional to the external magnetic field generated at that time. It is a thing. This is because the detection sensitivity of the MI element is proportional to the length of the MI element and the number of turns of the coil, so that the length is required in the direction of the detection magnetic field.

On the other hand, Patent Document 1 describes an integrated MI sensor device having an X-axis element and a Y-axis element arranged on one substrate and having a Z-axis element function. A pair of X1 elements and X2 elements and Y1 elements and Y2 elements are arranged in a cross shape on the substrate surface in the X-axis direction and the Y-axis direction, respectively, and a permalloy mandrel is arranged as a magnetic field modifier below the center point. .. This device detects a three-dimensional magnetic field vector by first adding the outputs of the X1 element and the X2 element to the magnetic field in the X-axis direction, and adding the outputs of the Y1 element and the Y2 element to the magnetic field in the Y-axis direction. Further, the magnetic field in the Z-axis direction generates a conversion component in the plane direction by the permalloy mandrel, and the difference between the output of the X1 element and the X2 element and the difference between the output of the Y1 element and the Y2 element. It is detected by adding and.
However, since the force of the permalloy mandrel to convert the magnetic field in the Z-axis direction in the plane direction is extremely weak, a long and large-diameter permalloy is required, and the thickness of the device is 0.5 mm or more, which is not practical.

In Patent Document 2, a magnetic field detection element of a type that detects a magnetic field in a direction parallel to the magnetic field detection element axis is used, and four magnetic field detection elements are placed on the substrate surface along the first axis direction with the origin as the center. A structure in which two are arranged along the second axis direction intersecting the first axis, and a soft magnetic material is arranged in the substrate below the origin and above the end opposite to the origin of the four elements. By having a magnetic field detection unit that forms a magnetic circuit between the magnetic field detection element and the soft magnetic material, the strength of the magnetic field in the X-axis, Y-axis, and Z-axis directions can be effectively measured from the outputs of the four magnetic field detection elements. The three-dimensional magnetic field detection element to be detected is described.
The height of the upper soft magnetic material of the element is about 0.05 mm to 0.2 mm, and the lower soft magnetic material has the same size, and the upper soft magnetic material, the magnetic field detection element, and the lower soft magnetic material have the same size. The three parts are arranged in a crank shape.

The function of the crank-shaped magnetic circuit is that the magnetic field in the Z-axis direction flows from the soft magnetic material at one end of the element through the magnetic sensitive body in the element to the other soft magnetic material. Since the magnetic field in the Z-axis direction is redirected in the X-axis and Y-axis directions and passes through the magnetic sensory body in each element, each element can detect a strong magnetic field proportional to the magnetic field in the Z-axis direction. As a result, even if the soft magnetic materials at both ends are small, a large output can be obtained. Therefore, if this magnetic circuit is utilized, the height of the three-dimensional magnetic field detection element can be reduced from the 0.5 mm level of Patent Document 1 to about 0.10 mm to 0.30 mm.
However, although it is possible to perform detection much more effectively than the detection force of Patent Document 1, it is difficult to obtain sufficient magnetic field detection sensitivity in the Z-axis direction as compared with the magnetic field detection sensitivity in the X-axis direction and the Y-axis direction. Is. In order to obtain sufficient magnetic field detection sensitivity in the Z-axis direction, it is necessary to increase the size of each soft magnetic material, so that the enlarged soft magnetic material also creates a magnetic circuit for magnetic fields in the X-axis direction and the Y-axis direction. By forming and detecting by excessively collecting and detecting the magnetic fields in the X-axis direction and the Y-axis direction, the balance with the magnetic field detection force in the Z-axis direction becomes poor, and the measurement range in the X-axis direction and the Y-axis direction is narrowed. There was a problem that it became. In addition, there is a problem that manufacturing is difficult due to a complicated shape and large parts.

WO2010 / 110456 Patent No. 602239

In view of the thinning of mobile devices equipped with an electronic compass, the present inventors have set the height of the three-dimensional magnetic field detection element to 0.10 mm or less, and the magnetic field detection sensitivity in the Z-axis direction is magnetic field detection in the X-axis and Y-axis directions. We decided to aim to realize a three-dimensional magnetic field detection element that has the same sensitivity. In the conventional magnetic field transforming body or magnetic circuit structure, it is difficult to make the magnetic field detection sensitivity in the Z-axis direction equal to the magnetic field detection sensitivity in the X-axis and Y-axis directions with a very thin element structure.

The present inventor has come up with the idea of effectively collecting a magnetic field in the Z-axis direction with a soft magnetic plate that widely covers the substrate surface, and is a surface on which a magnetic field detection element is arranged (hereinafter referred to as a magnetic field detection element arrangement surface). Soft magnetic plate is provided on the lower part and the upper part in parallel with the magnetic field detection element arrangement surface, and the ends and the lower part of each magnetic field detection element arranged point-symmetrically with respect to the origin on the magnetic field detection element arrangement surface. By magnetically connecting the soft magnetic material plates and magnetically connecting the other end of each magnetic field detection element and the upper soft magnetic material plate, a wide magnetic collecting surface and demagnetizing surface are provided in the Z-axis direction. By forming a magnetic circuit, the magnetic field in the Z-axis direction is effectively detected, the magnetic field detection sensitivities in the X-axis, Y-axis, and Z-axis directions are equalized, and the height of the three-dimensional magnetic field detection element is extremely high. I devised to make it smaller.
The magnetic field detection element is intended for GSR elements that can realize small size, high sensitivity, low noise, and wide range, but it is possible to form a magnetic circuit by using a conductive wire (called a magnetic wire) as a magnetic sensor. It can also be applied to FG sensor elements and MI sensor elements that can be used.

In the first invention, four magnetic field detection elements of a type that detect a magnetic field in a direction parallel to a magnetic field detection element arrangement surface on a substrate surface are placed at point-symmetrical positions centered on the origin of the substrate, and a magnetic field in the X-axis direction. Two are arranged to detect the magnetic field in the Y-axis direction, two are arranged to detect the magnetic field in the Y-axis direction, and the lower soft magnetic material plate and four magnetic fields are arranged below the magnetic field detection element arrangement surface in parallel with the magnetic field detection element arrangement surface. Four upper soft magnetic material plates are arranged on the upper part of the detection element, and the lower soft magnetic material plate and the magnetic sensitive body of the four magnetic field detection elements are magnetically connected via the lower soft magnetic material at the origin position. At the end opposite to the origin, the magnetic sensors of the four magnetic field detection elements and the four upper soft magnetic plates are magnetically connected via the upper soft magnetic wire, and the Z-axis direction magnetic field is applied to the upper and lower parts. By forming a magnetic circuit that effectively collects magnetism on one side of the soft magnetic material plate, applies magnetic flux to the magnetic sensor of each element in the X-axis direction and Y-axis direction, and demagnetizes on the other soft magnetic material plate. , X-axis direction, Y-axis direction, and Z-axis direction. The three-dimensional magnetic field detection element is characterized by measuring magnetic field components in three directions and detecting a magnetic field vector at the origin position.
Here, the lower soft magnetic material means a soft magnetic material that connects the lower soft magnetic material plate and the magnetic sensor that constitutes the magnetic field detection element, and the upper soft magnetic material constitutes the upper soft magnetic material plate and the magnetic field detection element. A soft magnetic material that connects to a magnetically sensitive material.

This magnetic circuit is a soft magnetic plate at the bottom and top, and by boldly using a large area of the entire surface of the substrate to collect and demagnetize a large amount of magnetic flux in the Z-axis direction, it effectively detects the magnetic field in the Z-axis direction. Is possible. It is desirable that the magnetic field detection sensitivities of the magnetic field detection elements in the X-axis, Y-axis, and Z-axis directions be the same, but if there is a difference, it shall be adjusted by the electronic circuit and the compensation program.

The magnetic field detection element has four electrodes, a + side electrode for output, a-side electrode, a + side electrode for energizing a magnetic wire which is an internal magnetic sensor, and a-side electrode, and is on the substrate surface. An electrode surface is required on the substrate for the electrode for connecting the magnetic field detection element and the external electronic circuit, and the upper soft magnetic material plate needs to be arranged so as not to cover this electrode surface. Regarding the negative side electrode for energizing the magnetic wire inside each magnetic field detection element, an electrode is provided at the origin position, and it is common to the four magnetic field detection elements, and the remaining three, for a total of twelve electrodes, are origin-symmetrical. It is necessary to place it on the substrate surface and wire it to the magnetic field detection element on the substrate surface.

The upper soft magnetic plate is connected at the end opposite to the origin of the magnetic wire inside each magnetic field detection element. That is, since the upper soft magnetic material plate is connected to the vicinity of the + side electrode wiring portion of the magnetic wire, when the upper soft magnetic material plates come into contact with each other, each magnetic field detection element is electrically short-circuited. The soft magnetic plates must not come into contact with each other.

As mentioned above, the area that can be used by the upper soft magnetic plate is limited in order to secure a space for the electrodes and prevent an electrical short circuit. As a result, the magnetic field detection force in the Z-axis direction is reduced, but the magnetic field detection force in the Z-axis direction can be maintained by making the area of the lower soft magnetic material plate wider than the total area of the four upper soft magnetic material plates. it can. Further, in order to stabilize the magnetic flux flowing through each magnetic field detection element, it is necessary that the magnetic circuit is symmetrical. Since the upper soft magnetic plate is arranged in a point-symmetrical shape centered on the origin, the space for the electrode can also be secured in a point-symmetrical shape centered on the origin, so that each magnetic field detection element can be provided. It is desirable that the electrode wiring also has a point-symmetrical shape centered on the origin.
If ideal point symmetry cannot be ensured due to manufacturing reasons or other reasons, the sensitivity of the X-axis, Y-axis, and Z-axis may increase or decrease and mutual interference may occur. It is desirable to solve these problems by compensation for sensitivity and mutual interference.
That is, the second invention has a space that can be joined to an external electronic circuit in a point-symmetrical shape centered on the origin, and the area of the lower soft magnetic plate is the total of the upper four soft magnetic plates. By making it wider than the area, the magnetic circuit formed by the lower soft magnetic material plate, the four magnetic field detection elements, and the upper soft magnetic material plate effectively detects the magnetic field in the Z-axis direction, and the X-axis direction and the Y-axis direction. It is a three-dimensional magnetic field detection element characterized by measuring magnetic field components in three directions in the direction and the Z-axis direction with the same sensitivity and detecting a magnetic field vector at the origin position.

A type of magnetic field detection element that detects a magnetic field in a direction parallel to the four magnetic field detection element arrangement surfaces is arranged on this substrate surface, and is soft on the upper and lower parts of the magnetic field detection element arrangement surface in parallel with the magnetic field detection element arrangement surface. In the three-dimensional magnetic field detection element in which the magnetic material plate is arranged, the magnetic field detection element and the soft magnetic material plate are close to each other, and the magnetic field detection element and the soft magnetic material plate are magnetically connected to form a magnetic circuit. Therefore, the influence of each soft magnetic plate on the magnetic sensitivity of each magnetic field detection element cannot be ignored.

The size of the area of the upper soft magnetic material plate and the lower soft magnetic material plate is directly related to the ability to collect magnetic flux in the Z-axis direction, and the larger the area of both, the more magnetic flux in the Z-axis direction is collected, and more magnetic flux is collected. Since it flows through the magnetic field detection element, the magnetic sensitivity in the Z-axis direction increases, and the smaller the area, the less magnetic flux in the Z-axis direction can be collected. Therefore, only a small amount of magnetic flux flows through each magnetic field detection element, and the magnetic flux in the Z-axis direction The magnetic sensitivity is low.

The influence on the magnetic sensitivity in the X-axis direction and the Y-axis direction is related to the shape and positional relationship of the magnetic field detection element, the upper soft magnetic plate, and the lower soft magnetic plate.

The magnetic fluxes in the X-axis direction and the Y-axis direction flow along the magnetic wire inside the magnetic field detection element, the upper soft magnetic material plate, and the lower soft magnetic material plate, but the upper and lower soft magnetic material plates absorb the magnetic flux. , The magnetic flux flowing through the magnetic wire is smaller than when the upper and lower soft magnetic plates are not present, but the magnetic flux can be increased or decreased by forming a magnetic circuit from the upper and lower soft magnetic plates and the magnetic wire. It can be prevented.

The upper soft magnetic plate is connected at the end opposite to the origin of each magnetic flux detection element, and is arranged point-symmetrically with respect to the origin in each axial direction together with the magnetic flux detection element in the X-axis direction and. When the magnetic flux in the Y-axis direction is collected, a magnetic circuit is formed in which the magnetic flux flows toward the other magnetic field detection element and the upper soft magnetic material plate, and a part of the collected magnetic flux is transferred to the magnetic wire inside the magnetic field detection element. Since it flows in and increases the magnetic flux flowing in each axial direction, it acts as an amplifier for the magnetic field detection elements in the X-axis direction and the Y-axis direction. Since the amount of magnetic flux absorbed by the upper soft magnetic material plate is determined by the size of the upper soft magnetic material plate, the larger the upper soft magnetic material plate, the more magnetic flux flows in the magnetic field detection element, and the X-axis direction and the Y-axis direction The magnetic sensitivity of the load increases.

The lower soft magnetic material plate is connected at the end on the origin side of each magnetic field detection element, but for magnetic fields in the X-axis direction and the Y-axis direction, the lower soft magnetic material plate is the above-mentioned upper soft magnetic material. A plane that is below the magnetic wire inside each magnetic field detection element, which is the main flow path of the magnetic circuit formed by the body plate and the magnetic field detection element, and is parallel to the magnetic field in the X-axis direction and the Y-axis direction. Since it spreads upward, the magnetic flux easily flows toward the inside of the plate on the same plane as the magnetic wires on the planes with different heights, so the magnetic flux collected by the lower soft magnetic plate from one end is , Passes through to the other end and is demagnetized with almost no effect on the magnetic wire inside each magnetic field detection element. That is, the lower soft magnetic plate acts as an attenuator for each magnetic field detection element because it acts as a detour for the magnetic flux inside the magnetic field detection element and reduces the magnetic flux flowing through the magnetic wire. The larger the lower soft magnetic material plate, the lower the magnetic sensitivity in the X-axis direction and the Y-axis direction.

As described above, when the upper soft magnetic plate is enlarged, the magnetic sensitivity in the Z-axis direction is increased, but the magnetic sensitivity in the X-axis direction and the Y-axis direction is amplified. Excessive amplification of magnetic sensitivity is not desirable because it leads to imbalance of magnetic sensitivity in each axial direction and reduction of measurement range. Further, when the lower soft magnetic material plate is enlarged, the detection force of the magnetic field component in the Z-axis direction is increased, but the magnetic sensitivity in the X-axis direction and the Y-axis direction is attenuated. High sensitivity is desired as a magnetic field detection element, and it is not desirable that the magnetic sensitivity is attenuated.

Therefore, in this three-dimensional magnetic field detection element, by adjusting the shapes of the upper soft magnetic material plate and the lower soft magnetic material plate, the effect that the upper soft magnetic material plate amplifies the magnetic sensitivity in the X-axis direction and the Y-axis direction. And, the effect that the lower soft magnetic material plate attenuates the magnetic sensitivity in the X-axis direction and the Y-axis direction just cancels each other, and the magnetic sensitivity in the Z-axis direction and the magnetic sensitivity in the X-axis direction and the Y-axis direction are the same. I did it.

That is, assuming that each magnetic field detection element in the X-axis direction and the Y-axis direction receives and outputs a magnetic field in the X-axis direction and a magnetic field in the Y-axis direction when the soft magnetic material constituting the magnetic circuit does not exist. As this three-dimensional magnetic field detection element, the outputs of the two magnetic field detection elements arranged in each axial direction are added to obtain an output, so that the output in the X-axis direction and the Y-axis direction as the three-dimensional magnetic field detection element is If the output of the magnetic field in the Z-axis direction obtained by each magnetic field detection element is ΔZ by passing the magnetic field in the Z-axis direction to each magnetic field detection element by a magnetic circuit, the outputs of the four elements are added to obtain the output. Therefore, since the output in the Z-axis direction as the three-dimensional magnetic field detection element is 4ΔZ, 4ΔZ = 2, that is, ΔZ = 0.5, so that the sensitivity in each axial direction of each magnetic field detection element and the Z-axis direction The shapes of the upper soft magnetic plate and the lower soft magnetic plate were adjusted so that the ratio to the sensitivity was 1: 0.5 and the magnetic sensitivity in each axial direction of each magnetic field detection element was neither amplified nor attenuated.
In the three-dimensional magnetic field detection device, the magnetic sensitivity can be adjusted by the amplification degree of the electronic circuit. Therefore, the magnetic sensitivity in the Z-axis direction and the magnetic sensitivity in the X-axis direction and the Y-axis direction are the same in the three-dimensional magnetic field detection element. This means that the ratio of the magnetic sensitivity in the Z-axis direction to the magnetic sensitivity in the X-axis direction and the Y-axis direction falls within the range of ± 70% of the ideal sensitivity ratio. That is, ΔZ is allowed in the range of 0.35 to 0.85.

By adjusting the magnetic field detection sensitivity of the elements in the X-axis, Y-axis, and Z-axis directions as described above, the three-dimensional magnetic field detection device configured by the three-dimensional magnetic field detection element first obtains a three-dimensional magnetic field vector. The magnetic field in the X-axis direction is detected by adding the outputs of the X1 element and the X2 element, the magnetic field in the Y-axis direction is detected by adding the outputs of the Y1 element and the Y2 element, and the magnetic field in the Z-axis direction is further detected. The collected Z-axis magnetic field is converted in the X-axis direction and the Y-axis direction by a magnetic circuit and passed through each magnetic field detection element, and the difference between the output of the X1 element and the X2 element and the difference between the output of the Y1 element and the Y2 element. It can be detected by adding and.

That is, in the third invention, a magnetic field detection element of a type that detects a magnetic field in a direction parallel to the four magnetic field detection element arrangement surfaces is arranged on the substrate surface, and the magnetic field detection element is arranged in parallel with the magnetic field detection element arrangement surface. In a three-dimensional magnetic field detection element in which soft magnetic material plates are arranged at the upper and lower parts of a surface to form a magnetic circuit, the influence of each soft magnetic material plate on the magnetic sensitivity in the X-axis direction and the Y-axis direction is canceled out, and Z It is a three-dimensional magnetic field detecting element characterized by effectively detecting a magnetic field in the axial direction and having equal magnetic sensitivities in each of the X-axis direction, the Y-axis direction, and the Z-axis direction.

The lower soft magnetic material plate and the upper soft magnetic material plate are arranged in the lower part and the upper part of the magnetic field detection element arrangement surface in parallel with the magnetic field detection element arrangement surface, respectively, but thinning is desired as a three-dimensional magnetic field detection element. Therefore, it is desirable that the distance between the lower soft magnetic plate and the upper soft magnetic plate is small.

However, each magnetic field detection element and each soft magnetic material plate are magnetically connected by arranging a soft magnetic material between the magnetic field detection element and the soft magnetic material plate at the connection portion of the soft magnetic material. If the height is small, the demagnetic field becomes strong, so the magnetic resistance increases, the magnetic flux flowing through the magnetic circuit decreases, and the magnetic sensitivity in the Z-axis direction decreases. Therefore, each magnetic field detection element and each soft magnetic material The soft magnetic material that connects the plates needs to have a certain height.

Therefore, by enlarging each soft magnetic material plate and further enlarging the magnetic collecting surface and the magnetizing surface to increase the magnetic flux flowing through the magnetic circuit, the height of the soft magnetic material is reduced and the magnetic flux is generated in the magnetic circuit. If a magnetic flux that exceeds the effect of making it difficult to flow is flowed into the magnetic circuit, the distance between the lower soft magnetic material plate and the upper soft magnetic material plate can be reduced without reducing the magnetic sensitivity in the Z-axis direction. ..

When the diameter of the magnetic wire is 10 μm, both soft magnetic plates need to be separated from the substrate surface by 5 μm or more, so that the distance between the two soft magnetic plates is at least 0.01 mm. The larger the distance between the two soft magnetic plates, the easier it is to increase the sensitivity of the Z-axis, but when the goal is to make it as small as possible, 0.08 mm or less is desirable.

That is, in the fourth invention, four magnetic field detection elements of the type that detect a magnetic field in a direction parallel to the magnetic field detection element arrangement surface are arranged on the substrate surface, and the magnetic field detection element is arranged in parallel with the magnetic field detection element arrangement surface. In a three-dimensional magnetic field detection element that forms a magnetic circuit by arranging soft magnetic material plates on the upper and lower parts of the surface, soft magnetic field is arranged at a connection portion that magnetically connects each magnetic field detection element and each soft magnetic material plate. The feature is that the height of the body can be reduced and the distance between the lower soft magnetic plate and the upper soft magnetic plate can be reduced from 0.01 mm or more to 0.08 mm or less to lower the overall height. It is a three-dimensional magnetic field detection element.

The size of the fourth invention is that the three-dimensional magnetic field detection element has a length of 0.2 mm or more and 1.0 mm or less, a width of 0.2 mm or more and 1.0 mm or less, and a thickness of 0.01 mm or more and 0.35 mm or less. Below, the height from the lower surface of the lower soft magnetic plate to the upper surface of the upper soft magnetic plate is 0.01 mm or more and 0.08 mm or less.

In this three-dimensional magnetic field detection element, when arranging the lower soft magnetic material plate, a digging method is performed in which a region having a large area other than the magnetic field detection element arrangement position on the substrate is dug down and the lower soft magnetic material plate is formed there. A stacking method is conceivable in which the lower soft magnetic material plate is formed in a wide area on the substrate and then the magnetic field detection element arrangement surface is formed with resin or the like.

An electrode for connecting to an external electronic circuit is arranged on a magnetic field detection element arrangement surface in a sufficiently wide space, and the height from the magnetic field detection element arrangement surface on which the electrode is arranged to the upper surface of the upper soft magnetic material plate is sufficient. If it is small, the three-dimensional magnetic field detection element and the integrated circuit chip which is an external electronic circuit can be flip-chip solder-bonded, and the three-dimensional magnetic field detection element and the external electronic circuit can be easily connected. The overall thickness of the three-dimensional magnetic field detection device configured by connecting the integrated circuit chip and the three-dimensional magnetic field detection element can be reduced.

It is also conceivable to form a three-dimensional magnetic field detection element directly on the integrated circuit chip.
In this case, an upper soft magnetic material plate is formed on the upper surface of the integrated circuit chip, a magnetic field detection element arrangement surface is formed on the upper surface of the integrated circuit chip, and a lower soft magnetic material plate is further arranged on the upper surface after the magnetic field detection element is arranged. By directly connecting each magnetic field detection element and the integrated circuit chip by wiring plating, a three-dimensional magnetic field detection device in which the integrated circuit chip and the three-dimensional magnetic field detection element are integrated is configured. This makes it possible to further reduce the thickness.
In the method of stacking the integrated circuit chips on the bottom, the connection side of the three-dimensional magnetic field detection element with the external electronic circuit, that is, the side facing the integrated circuit chip is defined as the upper part of the three-dimensional magnetic field detection element. Therefore, there is a reversal of the notation that the upper soft magnetic material plate is on the side closer to the integrated circuit chip, that is, the lower side, and the lower soft magnetic material plate is on the side farther from the integrated circuit chip, that is, the upper side, but the structure of the three-dimensional magnetic field detection element is It is the same.

As described above, the fifth invention is a three-dimensional magnetic field detection device characterized in that a three-dimensional magnetic field detection element is formed on an integrated circuit chip and directly wired and plated.

It is XY plan view of the 3D magnetic field detection element which concerns on Example 1. FIG. It is a ZX plan view of the 3D magnetic field detection element which concerns on Example 1. FIG. It is a top view which shows the basic structure of a GSR element. It is a ZX plan view of the magnetic circuit with respect to the magnetic field in the Z-axis direction which concerns on Example 1. FIG. It is a ZX plan view of the magnetic circuit with respect to the magnetic field in the X-axis direction which concerns on Example 1. FIG. It is an electronic circuit diagram of the magnetic field detection element which concerns on Example 1. FIG. It is an electronic circuit diagram of the 3D magnetic field detection element which concerns on Example 1. FIG. It is a figure of the junction of the 3D magnetic field detection element which concerns on Example 1 and an external electronic circuit. It is XY plan view of the 3D magnetic field detection element which concerns on Example 2. FIG. It is a figure of the junction of the 3D magnetic field detection element which concerns on Example 3 and an external electronic circuit.

The present invention will be described in more detail with reference to embodiments of the invention.
The three-dimensional magnetic field detection element of the present invention
Four magnetic field detection elements of the type that detect the magnetic field in the direction parallel to the magnetic field detection element placement surface on the substrate surface or on the integrated circuit chip without using the substrate (hereinafter referred to as the substrate, etc.) are the origins of the substrate, etc. Two are placed at point-symmetrical positions centered on the above to detect the magnetic field in the X-axis direction, and two are placed to detect the magnetic field in the Y-axis direction, and the magnetic field is detected parallel to the magnetic field detection element placement surface. A lower soft magnetic plate is placed below the element placement surface, and four upper soft magnetic plates are placed above the four magnetic field detection elements, and the lower soft magnetic plate and the magnetic sensors of the four magnetic field detection elements are arranged at the origin position. Is magnetically connected via the lower soft magnetic material, and at the end opposite to the origin, the magnetic sensitive bodies of the four magnetic field detection elements and the four upper soft magnetic material plates are magnetically connected via the upper soft magnetic material. By connecting, the magnetic field in the Z-axis direction is effectively collected on one of the upper and lower soft magnetic material plates, and the magnetic flux is applied to the magnetic sensor (magnetic wire) of each magnetic field detection element in the X-axis direction and the Y-axis direction. By forming a magnetic circuit that flows and demagnetizes with the other soft magnetic material plate, the magnetic field components in the three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction are measured, and the magnetic field vector at the origin position is detected. It is a thing.

Further, the three-dimensional magnetic field detection device of the present invention is
With integrated circuit chips
Two upper soft magnetic plates formed in the magnetic field direction in the X-axis direction and the Y-axis direction at point-symmetrical positions centered on the origin of the integrated circuit chip via an insulating material on the upper surface of the integrated circuit chip. The four upper soft magnetic plates composed of the two upper soft magnetic plates formed in the direction of the magnetic field of the above, and the four upper soft magnetic plates arranged above the upper soft magnetic plates corresponding to the upper soft magnetic plates. Four magnetic field detection elements consisting of two magnetic field detection elements for detecting a magnetic field in the X-axis direction and two other magnetic field detection elements for detecting the magnetic field in the Y-axis direction, and four magnetic field detection elements. One lower soft magnetic plate formed on the upper part of the surface on which the magnetic field detection element is arranged (referred to as a magnetic field detection element arrangement surface), four ends of the upper soft magnetic plate opposite to the origin, and four. An upper soft magnetic material that magnetically connects the end of the magnetic field sensing element of the magnetic field detecting element, the other end of the four magnetic field sensing elements of the four magnetic field detecting elements, and the central portion of the lower soft magnetic material plate. By providing a lower soft magnetic material that magnetically connects with
A magnetic circuit including the lower soft magnetic material plate, the lower soft magnetic material, the magnetic sensitive material of the magnetic field detection element, the upper soft magnetic material, and the upper soft magnetic material plate is formed.
It is characterized by comprising a wiring for joining the integrated circuit chip and the magnetic field detection element.

As a result, the three-dimensional magnetic field detection device can be made thinner by forming the three-dimensional magnetic field detection element that directly detects the magnetic fields in the X-axis direction, the Y-axis direction, and the Z-axis direction on the integrated circuit chip.

A GSR element is desirable as each magnetic field detection element in the three-dimensional magnetic field detection element. The GSR element has a magnetic body that can generate rotation of electron spins in response to magnetism and a detection means for detecting magnetic changes in the magnetic body, and the magnetic body is not limited in its material or form. Further, the detection means is a detection coil that is wound around a magnetic sensitive body and outputs an electromotive force according to a change in the amount of magnetic flux. The magnetic sensitive material is usually made of a soft magnetic material such as an amorphous wire, and is made of a wire or a thin film having an appropriate length. As the magnetic sensitive material, an amorphous wire having zero magnetostriction is particularly preferable in terms of magnetic field detection ability, strength, cost and the like.

The upper soft magnetic plate and the lower soft magnetic plate (hereinafter referred to as soft magnetic plates) are X1 elements, X2 elements, which are arranged in a magnetic field in the X-axis direction at point-symmetrical positions about the origin of the substrate or the like. A magnetic circuit is formed by Y1 elements and Y2 elements arranged in a magnetic field in the Y-axis direction, and soft magnetic materials (upper soft magnetic material and lower soft magnetic material) connecting each element and each soft magnetic material plate, and in the Z-axis direction. By directing the magnetic field in the X-axis direction and the Y-axis direction and flowing it through each element, it is possible to effectively detect the strength of the magnetic field in the Z-axis direction. The soft magnetic material of the soft magnetic material plate and the connection portion may be made of any material as long as such a magnetic circuit can be formed. As the soft magnetic material, the higher the magnetic permeability, the greater the magnetic collecting effect, so that a permalloy alloy is usually desirable.

As for the shape of the soft magnetic material plate, the larger the area, the more magnetic flux in the direction perpendicular to the plate surface can be collected. Therefore, it is preferable that the soft magnetic material plate has as large an area as possible, but at the end of the magnetic sensitive material in the GSR element. The closer it is, the more the soft magnetic plate absorbs the magnetic flux that the magnetic sensor on the substrate surface should collect, and the greater the influence on the magnetic sensitivity of the GSR element. Therefore, it is preferable to control the influence on the magnetic sensitivity of the GSR element by making a notch in the soft magnetic material plate near the end portion of the magnetic sensitive material.

In addition, the thinner the soft magnetic plate, the stronger the demagnetic field in the vertical direction of the soft magnetic plate surface, and the easier it is for magnetic flux to flow in the horizontal direction. Therefore, the magnetic resistance of the magnetic circuit can be reduced effectively. Since the magnetic flux can be collected and the area with respect to the horizontal direction is reduced, the amount of absorption of the horizontal magnetic flux is reduced, and the influence on the magnetic sensitivity of the GSR element is reduced. Further, since a thin plate is advantageous for reducing the height of the entire three-dimensional magnetic field detection element, a thin soft magnetic plate is preferable. However, if it is too thin, the demagnetic field in the vertical direction of the plate surface becomes too strong and it becomes difficult to collect magnetic flux, so an appropriate thickness is required. This thickness is preferably about 0.005 mm to 0.020 mm.

In the present invention, since the two X-axis elements and the two Y-axis elements are arranged on the first and second axes that are orthogonal to each other, the angle formed by each axis on which each element is arranged should be a right angle. However, if there is a deviation in the angle, it can be dealt with by measuring the deviation angle and adding a correction calculation.

The upper soft magnetic material plates that form symmetrically arranged GSR elements or a magnetic circuit, or the soft magnetic material at each connection between the magnetic sensitive material inside the GSR element and each soft magnetic material plate, have sensitive characteristics, detection characteristics, or It is desirable that the magnetic collection characteristics and the like are substantially the same and that the magnetic circuit has symmetry. When the characteristics are different, the measured value of each element can be processed by being sent to the electronic circuit and the arithmetic processing unit, corrected and made the same.

In any case, the correction coefficient or correction term in the calculation formula can be simplified by skillfully utilizing the pair of GSR elements in the X-axis direction or the pair of GSR elements in the Y-axis direction and the symmetry of the magnetic circuit. Is preferable because it can facilitate highly accurate magnetic field detection.

In the present invention, since the magnetic field in the Z-axis direction is detected by forming a magnetic circuit with the X-axis element, the Y-axis element, and the soft magnetic material plate installed on the substrate, the three-dimensional magnetic field detection device is downsized or thin. It is characterized in that it can be transformed. Wiring between the three-dimensional magnetic field detection element of the present invention and the integrated circuit chip which is an external electronic circuit can be performed by wire bonding, but an extra area and height are required for wire bonding, and the three-dimensional magnetic field is required. Since the area of the detection element is small and the electrodes are close to each other, manufacturing difficulties also occur. Therefore, this three-dimensional magnetic field detection element is laminated on an integrated circuit chip and flip-chip solder-bonded, or a three-dimensional magnetic field detection element is formed directly on the integrated circuit chip, and the electrode of the integrated circuit chip and the magnetic field detection element are formed. It is desirable to join the wiring with the electrode by plating or vapor deposition between the two in order to promote overall miniaturization or thinning.

Further, the integrated layer is not limited to the three-dimensional magnetic field detection element and the integrated circuit chip layer. The three-dimensional magnetic field detection element of the present invention can be assembled and used as a composite sensor by being laminated with an acceleration sensor, a temperature sensor, or the like.

It will be described in detail based on the following examples with reference to the drawings.
[Example 1]
The three-dimensional magnetic field detection element 1 according to the first embodiment is shown in FIG. FIG. 1 (a) is an XY plan view of the three-dimensional magnetic field detection element 1, and FIG. 1 (b) is a view of a lower soft magnetic material plate extracted from FIG. 1 (a). FIG. 2 is a ZX plan view of the three-dimensional magnetic field detection element 1 viewed from the Y-axis direction, and the structure in the Y-axis direction is omitted for simplicity. FIG. 3 is a plan view showing the basic structure of the GSR element.

In the three-dimensional magnetic field detection element 1, four GSR elements 2 capable of detecting a minute magnetic field such as geomagnetism, that is, X1 element 2X1, X2 element 2X2, Y1 element 2Y1, Y2 element 2Y2, and these four GSR elements 2 are arranged. At the origin position, which is the center of the substrate, the magnetic field detection element arrangement surface 12 on the substrate 10 and the lower soft magnetic material plate 11 arranged in a wide recess provided by digging the magnetic field detection element arrangement surface 12. A soft magnetic material (lower soft magnetic material) 31 that connects a lower soft magnetic material plate 11 and a magnetic wire 21 that is a magnetic sensor inside each GSR element 2, and four upper soft magnetic materials arranged so as to cover each GSR element 2. A three-layer structure consisting of a soft magnetic material (upper soft magnetic material) 32 connecting the magnetic material plate 13, the magnetic wire 21 and the upper soft magnetic material plate 13 at the outer edge side end of the substrate 10 of the magnetic wire 21, that is, A three-layer structure consisting of a lower soft magnetic material plate 11, a magnetic field detection element arranging surface 12 and an upper soft magnetic material plate 13, and layers connected by the soft magnetic material 3 and a lower soft magnetic material plate 11 are provided. The recess is filled with an insulating material so that the height is the same as the magnetic field detection element arrangement surface 12, and this is used as the electrode arrangement surface 14, and the electrodes 22 of each GSR element 2 arranged there are formed.

The electrode 22 is provided with an electrode pad 221 as a negative electrode common to each of the magnetic wires 21 which are magnetic sensitive bodies of the four GSR elements 2 at the origin position of the substrate 10, and each of the electrodes 22 is located near the outer edge of the electrode arrangement surface 14. An electrode pad 222 serving as a + side electrode of the magnetic wire 21 is arranged, and a GSR element is placed along the magnetic wire 21 on the electrode arrangement surface 14 at a position facing the electrode arrangement surface 14 on which the electrode pad 222 is arranged with the magnetic wire 21 interposed therebetween. Two electrodes 223 on the + side and the-side of the detection coil 2 are installed side by side. Further, as shown in FIG. 8, by installing a solder pad for bonding on the electrode 22, it can be connected to the integrated circuit chip 5 which is an external electronic circuit by the flip chip solder bonding 8.

The lower soft magnetic plate 11 is formed by digging a wide shallow hole having a size of 260 μm square and a depth of 20 μm in the substrate 10 to form a dent, and the entire bottom thereof is plated to have a thickness of 45 at% at 10 μm. Four permalloy alloy plates with a Ni-Fe composition are formed, and a hole with a depth of 10 μm and a size of 80 μm is dug into a recess at the origin position, and the plate divided into four is made through the recess at the origin position. By forming a magnetic film having a thickness of 5 μm of a permalloy alloy having a 45 at% Ni—Fe composition so as to be joined by a plating method, one lower soft magnetic material plate 11 is formed.

The soft magnetic material (lower soft magnetic material) 31 that connects the lower soft magnetic material plate 11 and the magnetic wire 21 is 20 μm square and high in size by a plating method so as to come into contact with the magnetic wire 21 from the bottom of the recess at the origin position. It is a permalloy alloy having a 45atNi—Fe composition formed at a size of 10 μm.
The soft magnetic material (upper soft magnetic material) 32 that connects the upper soft magnetic material plate 13 and the magnetic wire 21 is 20 μm square in size from the magnetic wire 21 on the outer edge side of the substrate 10 of the magnetic wire 21 by a plating method. , A permalloy alloy having a 45 at% Ni—Fe composition formed at a height of 10 μm.

The upper soft magnetic plate 13 has a thickness of 5 μm by a plating method, a width of 100 μm which is the length along the outer edge of the substrate 10, and a magnetic wire 21 so as to be in contact with the upper surface of the soft magnetic material (upper soft magnetic material) 32. It forms a plate of a permalloy alloy having a 45 at% Ni—Fe composition having a vertical width of 175 μm, which is the length along the line.

For the lower soft magnetic material plate 11, the upper soft magnetic material plate 13, and the soft magnetic material 3, known soft magnetic materials such as pure Ni, pure iron, permalloy alloys having other compositions, sendust, and permendur can be used.

The structure of the GSR element 2 will be described with reference to FIG.
The four GSR elements have the same structure, and the structure is such that the amorphous wire, which is the magnetic wire 21 having a diameter of 10 μm and a length of 300 μm, is arranged in the center, and the inner diameter is 16 μm, the coil pitch is 5 μm, and the number of turns is 30. The detection coil 23 is arranged, and the wire connection terminal 24 and the detection coil connection terminal 25, which are electrode terminals, are attached to both ends of the magnetic wire 21 and the detection coil 23, respectively. The wire connection terminal 24 is connected to the electrodes 221 and 222, and the detection coil terminal 25 is connected to the electrode 223. The GSR element 2 uses four electrodes 22 respectively to correspond to an external electronic circuit (not shown). The terminals of each GSR element 2 and the terminals of the external electronic circuit are electrically joined by an electrode pad.

The lower soft magnetic plate 11 connected to the four elements of the GSR elements 2X1, 2X2, 2Y1 and 2Y2 arranged on the substrate of the first embodiment at the origin position is connected to the outer edge side of each element. A magnetic circuit is formed by the four upper soft magnetic plate 13s, which makes it possible to effectively detect the strength of the magnetic field in the Z-axis direction.

The function of this magnetic circuit with respect to the magnetic field in the Z-axis direction will be described with reference to FIG.
The magnetic field Hz in the Z-axis direction magnetizes the soft magnetic material 3, the soft magnetic material plates 11 and 13. Assuming that the lower surface of each soft magnetic material and the soft magnetic material plate is the S pole, the magnetic flux collected by the lower surface of the lower soft magnetic material plate 11 as the magnetic collecting surface is a strong countermagnetic field in the direction perpendicular to the plate surface. The S pole of the soft magnetic material 31 connected to the central part of the plate 11 and attracting magnetic flux is converted in the direction toward the central part of the plate 11 parallel to the surface of the plate 11, and the magnetic field passes through the soft magnetic material 31. It rises to the detection element arrangement surface 12 and flows toward the magnetic wire 21 in the X-axis and Y-axis directions connected by the N pole of the soft magnetic body 31, and the upper soft magnetic material plate is formed at the other end of the magnetic wire 21. It flows into the S pole of the soft magnetic material 32 connected to 13, flows from the N pole of the soft magnetic material 32 into the upper soft magnetic material plate 13, and is demagnetized from the upper soft magnetic material plate 13.

At this time, a strong magnetic field proportional to the magnetic field in the Z-axis direction flows through the magnetic wire 21 of the GSR element, and a large magnetic sensitivity in the Z-axis direction can be effectively obtained by forming this magnetic circuit. The height from the lower surface of the lower soft magnetic plate 11 to the upper surface of the upper soft magnetic plate 13 is 20 μm dug from the magnetic field detection element arrangement surface 12, and the height at which the magnetic wire 21 protrudes from the magnetic field detection element arrangement surface 12 is 5 μm. The total thickness of the soft magnetic material 32 and the upper soft magnetic material plate 13 is 40 μm, and the lower soft magnetic material plate 11 is arranged by digging the substrate 10, so that the actual height of the three-dimensional magnetic field detection element 1 is high. The height from the magnetic field detection element arrangement surface 12 to the upper surface of the upper soft magnetic plate 13 is 20 μm, and the height of the entire three-dimensional magnetic field detection element 1 is set to 0, including the thickness of the substrate 10 of 0.1 mm. It could be 12 mm.

The function of this magnetic circuit with respect to magnetic fields in the X-axis direction and the Y-axis direction will be described with reference to FIG.
The magnetic field Hx in the X-axis direction magnetizes the soft magnetic material 3, the soft magnetic material plates 11 and 13, and the magnetic wires 21 of the X1 element and the X2 element. Assuming that the left side in FIG. 5 of each magnetic material is the S pole, first, a part of the magnetic flux collected by the upper soft magnetic material plate 13 on the S pole side passes through the soft magnetic material (upper soft magnetic material) 32 and the magnetic wire. The magnetic flux that flows into 21 and passes through the magnetic wire 21 on the magnetizing side flows into the magnetic wire 21 on the magnetizing side via the central portion of the soft magnetic material 31 and the lower soft magnetic material plate 11 at the origin position and becomes an N pole. At the right end, magnetism is emitted from the soft magnetic material (upper soft magnetic material) 32 and the upper soft magnetic material plate 13. The upper soft magnetic plate 13 and the magnetic wire 21 form a magnetic circuit, increase the magnetic flux flowing through the magnetic wire 21 and act as an amplifier for the magnetic sensitivity in the X-axis direction, and the magnitude of this effect is the magnitude of this effect. It depends on the shape of.

On the other hand, the lower soft magnetic plate 11 is located below the magnetic wire 21, which is the main flow path of the magnetic circuit formed by the upper soft magnetic plate 13 and the magnetic wire 21, and is in the X-axis direction. Since it spreads on a plane parallel to the magnetic field, magnetic flux easily flows toward the inside of the plate 11 on the same plane as the magnetic wires 21 on the planes having different heights, so that the lower soft magnetic material plate 11 The magnetic flux collected by the S pole passes through the north pole of the lower soft magnetic plate 11 and is demagnetized with almost no effect on the magnetic wire 21. That is, the lower soft magnetic plate 11 acts as a detour for the magnetic flux with respect to the magnetic wire 21 and reduces the magnetic flux flowing through the magnetic wire 21, so that it acts as an attenuator for the magnetic sensitivity in the X-axis direction, and the magnitude of this effect is lower. It depends on the shape of the soft magnetic plate 11.
The above is the same for the magnetic field in the Y-axis direction.

The function of the magnetic circuit formed by the upper soft magnetic plate 13, the lower soft magnetic plate 11, and the magnetic wire 21 against magnetic fields in the X-axis direction and the Y-axis direction is as an amplifier due to the shape of the upper soft magnetic plate 13 as described above. Since the shape of the lower soft magnetic material plate 11 has an effect as an attenuator, it is necessary to cancel both of these effects so as not to affect the magnetic wire. That is, it does not affect the magnetic sensitivity in the X-axis direction and the Y-axis direction.

The outputs of the four GSR elements 2 are individually measured, and assuming that the measured values of the X1 element 2X1, the X2 element 2X2, the Y1 element 2Y1, and the Y2 element 2Y2 are Hx1, Hx2, Hy1, and Hy2, the X axis is calculated. The magnetic field strengths Hx, Hy, and Hz in the direction, Y-axis direction, and Z-axis direction are calculated.

As described above, the X1 element 2X1, the X2 element 2X2, the Y1 element 2Y1, and the Y2 element 2Y2 are arranged point-symmetrically with respect to the origin, and the magnetic flux collected by the lower soft magnetic plate 11 is the magnetic field detection element from the origin. Since a magnetic circuit is formed that flows into the magnetic wire in a point-symmetric manner, the magnetic field in the Z-axis direction affects the X1 element 2X1 and the X2 element 2X2 and the Y1 element 2Y1 and the Y2 element 2Y2 in opposite directions, respectively. .. That is, the outputs corresponding to the magnetic field components in the Z-axis direction of the X1 element 2X1 and the X2 element 2X2 and the Y1 element 2Y1 and the Y2 element 2Y2 are proportional to the strength of the magnetic field in the Z-axis direction, and their signs are opposite.

Therefore, assuming that the amount of change in the output of each element due to the magnetic field in the Z-axis direction is ΔZ and the original outputs are Hx'and Hy', it is as follows.
Hx1 = Hx'+ ΔZ
Hx2 = Hx'-ΔZ
Hy1 = Hy'+ ΔZ
Hy2 = Hy'-ΔZ
Of these values, the value proportional to the strength of the magnetic field in the X-axis direction is Hx', the value proportional to the strength of the magnetic field in the Y-axis direction is Hy', and the value proportional to the strength of the magnetic field in the Z-axis direction. Is ΔZ. If the calculation process is performed so as to obtain an output proportional to the magnetic field component in only one direction, the magnetic field strengths Hx, Hy, and Hz in the X-axis direction, the Y-axis direction, and the Z-axis direction can be calculated.

In order to remove the influence of the magnetic field component in the Z-axis direction and obtain the magnetic field strengths Hx and Hy in the X-axis direction and the Y-axis direction, first, the outputs of the X1 element 2X1 and the X2 element 2X2 and the Y1 element 2Y1 and the Y2 element 2Y2 are output. Each of them may be added to eliminate ΔZ.
Hx = Hx1 + Hx2 = 2Hx'
Hy = Hy1 + Hy2 = 2Hy'
Further, in order to obtain the magnetic field strength Hz in the Z-axis direction, a component proportional to the magnetic field strength in the X-axis direction and the Y-axis direction may be removed, so that the difference between the outputs of the X1 element 2X1 and the X2 element 2X2 The difference between the outputs of the Y1 element 2Y1 and the Y2 element 2Y2 may be added.
Hz = (Hx1-Hx2) + (Hy1-Hy2) = 4ΔZ
From the above, the strengths Hx, Hy, and Hz of the magnetic field components in each axial direction can be calculated. At this time, if Hx = Hy = Hz = 2, then Hx'= Hy'= 1 and ΔZ = 0.5. In order to make the magnetic sensitivities in each axial direction uniform, the sensitivity ratio of each X element and each Y element may be Hx': Hy': ΔZ = 1: 1: 0.5, and this three-dimensional magnetic field detection element This sensitivity ratio can be achieved by the function of the magnetic circuit.

The electronic circuit 4 for driving the three-dimensional magnetic field detection element 1 used in this embodiment will be described with reference to FIGS. 6 and 7.
First, the basic operation of the electronic circuit 4 of the GSR sensor will be described with reference to FIG. The electronic circuit 4 includes a pulse transmitter 41 and a signal processing circuit 42. The signal processing circuit 42 includes a sample timing adjustment circuit 421, an electronic switch 422, a sample hold circuit 423, and an amplifier 424. A high-frequency pulse current equivalent to 1.3 GHz generated by the pulse transmitter 41 is supplied to the amorphous wire 21 of the GSR element 2. Then, the magnetic field generated in the wire circumferential direction of the amorphous wire 21 and the external magnetic field act due to the pulse current, and a voltage corresponding to the external magnetic field is generated in the detection coil 23.
The pulse frequency here is conveniently defined with twice the "falling down" time Δt of the pulse current as its period and its reciprocal as the pulse frequency.

The output voltage of the detection coil 23 is measured by the sample timing adjustment circuit 421 by switching the electronic switch 422 for a short time (on-off) of 0.1 nsec at a predetermined timing from the fall of the pulse current to the sample hold circuit 423. Is supplied to. At this time, the voltage generated in the detection coil 23 is held as the capacitor voltage of the sample hold circuit 423, and this sampling voltage is amplified by the amplifier 424 and output.

Next, the function of the electronic circuit 4 of this embodiment having four GSR elements will be described with reference to FIG. 7. In this circuit, the pulse transmitter 41 is one, and the signal processing circuit 42 is provided with four for simultaneously measuring the output of each element. The outputs from the four GSR elements are sequentially converted into digital signals by the AD converter 44 using the changeover switch 43, then transferred to the arithmetic circuit 45, appropriately subjected to arithmetic processing, and the strength of the three-dimensional magnetic field vector. Is converted to. After that, it is transferred to a central processing unit that controls a system such as a smartphone via a data communication circuit 46.

The joining of the three-dimensional magnetic field detection element 1 of this embodiment and the integrated circuit chip 5 which is an external electronic circuit 4 will be described with reference to FIG.
In the three-dimensional magnetic field detection element 1 of the present invention, the height from the electrode arrangement surface 14 on which the electrodes 22 of each GSR element 2 are arranged to the upper surface of the upper soft magnetic material plate is suppressed to a low value of 20 μm. The electrodes on the integrated circuit chip can be easily connected by laminating the three-dimensional magnetic field detection element 1 on the integrated circuit chip 5 and forming a flip chip solder joint 8 having a height of 20 μm. As a result, the thickness of the entire three-dimensional magnetic field detection device can be reduced to 0.15 mm for the ASIC substrate, 0.10 mm for the element substrate, 0.02 mm for the joint portion, and 0.27 mm as a whole.

[Example 2]
The three-dimensional magnetic field detection element 6 according to the second embodiment is shown in FIG. 9 (a) is an XY plan view of the three-dimensional magnetic field detection element 6, and FIG. 9 (b) is a view of the lower soft magnetic material plate extracted from FIG. 9 (a).
In the second embodiment, the lower soft magnetic plate 61 is first formed by a plating method using the entire surface of the substrate 60 without digging a hole in the substrate 60, and then the lower soft magnetic plate 61 is covered with an insulating material such as resin. The upper surface of this insulating material layer is used as the magnetic field detection element arranging surface 62 and the electrode arranging surface 64, and the GSR element 2, the upper soft magnetic material plate 63, the lower soft magnetic material plate 61 and the magnetic wire at the origin position are the same as in the first embodiment. It forms a soft magnetic material (lower soft magnetic material) 33 that connects 21 and a soft magnetic material (upper soft magnetic material) 34 that connects the magnetic wire 21 and the upper soft magnetic material plate 63.

The lower soft magnetic plate 61 can have a larger area than the lower soft magnetic plate 11 arranged by digging a hole in the substrate 10, and it is easy to increase the magnetic sensitivity to the magnetic field in the Z-axis direction. However, if the distance between the outer edge side end of the substrate 60 of the magnetic wire 21 and the lower soft magnetic plate 61 is too close, the damping effect on the magnetic sensitivity in the X-axis direction and the Y-axis direction becomes large, so that the magnetic wire 21 At the lower part, a notch is made in the lower soft magnetic material plate 61 to adjust the distance.

The size of the lower soft magnetic plate 61 is 560 μm square and the thickness is 5 μm, and the lower soft magnetic plate 61 is notched below the outer edge side end of the substrate 60 of the four magnetic wires 21. The shape of the notch is line-symmetrical around the magnetic wire 21, and the size of the notch is 100 μm along the outer edge of the substrate 60 and 50 μm along the magnetic wire 21.

The size of the upper soft magnetic plate 63 is 140 μm in width along the outer edge of the substrate 60, 225 μm in length along the magnetic wire 21, and 5 μm in thickness.

The soft magnetic material 33 that connects the lower soft magnetic material plate 61 and the magnetic wire 21 and the soft magnetic material 34 that connects the upper soft magnetic material plate 63 and the magnetic wire 21 are both 20 μm square in size and 5 μm in height.

Since the three-dimensional magnetic field detection element 6 uses the entire surface of the substrate 60 to expand the area of the lower soft magnetic material plate 61 to increase the magnetic sensitivity to the magnetic field in the Z-axis direction, the three-dimensional magnetic field detection element 6 and the lower surface of the lower soft magnetic material plate 61 The distance between the upper surfaces of the upper soft magnetic plate 63 can be reduced, and the distance between them is 30 μm including the diameter of the magnetic wire of 10 μm, which is smaller than that of the first embodiment. Together with the substrate thickness of 0.1 mm, the overall thickness of the three-dimensional magnetic field detection element 6 could be 0.13 mm. Since the magnetic field detection element arrangement surface 62 and the electrode arrangement surface 64 are at a height at which the magnetic wire 21 is half filled, the height from the electrode arrangement surface 64 to the upper surface of the upper soft magnetic plate 63 is 15 μm, and the flip height is 15 μm. By soldering the chips, it can be easily connected to the integrated circuit chip 5 which is an external electronic circuit 4. The thickness of the entire three-dimensional magnetic field detection device is 0.28 mm when the ASIC substrate is 0.150 mm, the element substrate is 0.100 mm, the height to the electrode arrangement surface is 0.015 mm, and the joint portion is 0.015 mm.

[Example 3]
In the third embodiment, the three-dimensional magnetic field detection element 7 in the first and second embodiments is formed directly on the integrated circuit chip 5 which is the electronic circuit 4 outside the three-dimensional magnetic field detection element. It is possible to eliminate the substrate and further reduce the thickness.
FIG. 10 shows the direct wiring plating joint 9 between the three-dimensional magnetic field detection element 7 and the integrated circuit chip 5 in the third embodiment.

In the third embodiment, the three-dimensional magnetic field detection element 7 is formed so as to stack layers with the upper surface on which the electrodes of the integrated circuit chip 5 are arranged as the bottom surface. At this time, since the connection side of the three-dimensional magnetic field detection element with the external electronic circuit is defined as the upper surface of the substrate surface, the three-dimensional magnetic field detection element 7 is formed from below as an inverted shape. That is, the upper soft magnetic plate is formed from the bottom so that the lower soft magnetic plate is on the uppermost side, and the lower soft magnetic plate is formed from the bottom so that the integrated circuit chip and the three-dimensional magnetic field detection element are joined to detect the three-dimensional magnetic field. The shape and positional relationship of each part as an apparatus are the same as those in the second embodiment except that the substrate 60 in the second embodiment is eliminated. At this time, the electrode 22 is joined to the integrated circuit chip 5 by the direct wiring plating joint 9 at the same time as the element formation.

The size and height of the three-dimensional magnetic field detection element 7 are the same as those of the three-dimensional magnetic field detection element 6 of the second embodiment except for the substrate 60. That is, the height of the three-dimensional magnetic field detection element 7 is 30 μm regardless of whether it is the height from the lower surface of the lower soft magnetic material plate to the upper surface of the upper soft magnetic material plate or the height of the entire three-dimensional magnetic field detection element. .. Therefore, the thickness of the three-dimensional magnetic field detection device is 0.1 mm less than that of the second embodiment, and can be made very thin to 0.18 mm.

The three-dimensional magnetic field detection element of the present invention is necessary for a three-dimensional azimuth meter that requires three-dimensional geomagnetic measurement such as an electronic compass and a magnetic gyro. In particular, the three-dimensional magnetic field detection device of the present invention includes a smartphone. It is suitable for those that need to be miniaturized and thinned in the direction perpendicular to the substrate to be mounted (so-called Z-axis direction), such as a portable terminal.

1: 3D magnetic field detection element of Example 1 10: Substrate of 3D magnetic field detection element of Example 1: Lower soft magnetic material plate of 3D magnetic field detection element of Example 1 12: 3D magnetic field of Example 1 Detection element arrangement surface 13: Upper soft magnetic material plate of the three-dimensional magnetic field detection element of Example 1: Electrode arrangement surface of the three-dimensional magnetic field detection element of Example 1: GSR element (2X1, 2X2, 2Y1, 2Y2 4) One element)
21: Magnetic wire (amorphous wire) that is a magnetic sensor of the GSR element
22: GSR element electrode 221: GSR element magnetic wire energization-side electrode 222: GSR element magnetic wire energization + side electrode 223: GSR element detection coil electrode 23: GSR element detection coil 24: Terminal for connecting the magnetic wire of the GSR element 25: Terminal for connecting the detection coil of the GSR element 3: Soft magnetic material 31: Soft magnetic material for connecting the magnetic wire of Example 1 and the lower soft magnetic material plate (lower soft magnetic material) )
32: A soft magnetic material (upper soft magnetic material) that connects the magnetic wire of Example 1 and the upper soft magnetic material plate.
33: A soft magnetic material (lower soft magnetic material) that connects the magnetic wire of Example 2 and the lower soft magnetic material plate.
34: A soft magnetic material (upper soft magnetic material) that connects the magnetic wire of Example 2 and the upper soft magnetic material plate.
4: Electronic circuit 41: Pulse transmitter 42: Signal processing circuit 421: Sample timing adjustment circuit 422: Electronic switch 423: Sample hold circuit 424: Amplifier 43: Changeover switch 44: AD converter 45: Arithmetic circuit 46: Data communication circuit 5 : Integrated circuit chip 6: Three-dimensional magnetic field detection of Example 2 60: Substrate of Example 2 61: Lower soft magnetic material plate of Example 2: Magnetic field detection element arrangement surface of Example 2 63: Upper part of Example 2 Soft magnetic plate 64: Electrode arrangement surface of Example 2: Three-dimensional magnetic field detection element of Example 3 8: Flip chip solder joint 9: Direct wiring plating joint

Claims (1)

With integrated circuit chips
Two upper soft magnetic plates formed in the magnetic field direction in the X-axis direction and the Y-axis direction at point-symmetrical positions centered on the origin of the integrated circuit chip via an insulating material on the upper surface of the integrated circuit chip. Four upper soft magnetic plates composed of two upper soft magnetic plates formed in the direction of the magnetic field of
Two magnetic field detection elements for detecting the magnetic field in the X-axis direction and the magnetic field in the Y-axis direction are detected, which are arranged on the upper part of the upper soft magnetic material plate corresponding to the four upper soft magnetic material plates. 4 magnetic field detection elements consisting of 2 other magnetic field detection elements for
One lower soft magnetic material plate formed on the upper part of the surface on which the four magnetic field detection elements are arranged (referred to as the magnetic field detection element arrangement surface), and
An upper soft magnetic material that magnetically connects the end portions of the four upper soft magnetic material plates opposite to the origin and the end portions of the magnetic sensitive bodies of the four magnetic field detection elements.
By providing a lower soft magnetic material that magnetically connects the other end of the four magnetic sensitive bodies of the four magnetic field detection elements and the central portion of the lower soft magnetic material plate.
A magnetic circuit including the lower soft magnetic material plate, the lower soft magnetic material, the magnetic sensitive material of the magnetic field detection element, the upper soft magnetic material, and the upper soft magnetic material plate is formed.
A three-dimensional magnetic field detection device comprising wiring for joining the integrated circuit chip and the magnetic field detection element.

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