Tunnel reluctance gyroscope and preparation method thereof

Abstract

The invention relates to the technical field of gyroscopes, and discloses a tunnel magnetoresistive gyroscope and a preparation method thereof, and the tunnel magnetoresistive gyroscope comprises a substrate; a magnetic field generating electrode, a first metal bump, and a plurality of second metal bumps; the magnetic field generating electrode comprises a first bus electrode and a plurality of first parallel electrodes of the first tuning fork electrode, and a second bus electrode and a plurality of second parallel electrodes of the second tuning fork electrode; the first bus electrode is connected with the first end of each first parallel electrode; the second bus electrode is connected with the first end of each second parallel electrode; the first parallel electrodes and the second parallel electrodes are staggered at intervals; the second end of each first parallel electrode is connected with the first bus electrode between two adjacent second parallel electrodes; the first metal bump is connected with the first bus electrode; and the second metal bump is connected with the second end of the second parallel electrode. Compared with the prior art, the reliability and the magnetic field detection precision of the tunnel reluctance gyroscope can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gyroscopes, and in particular to a tunnel magnetoresistive gyroscope and a preparation method thereof. Background Art

[0002] Gyroscopes are important inertial sensor devices commonly used in daily life and production. Tunnel magnetoresistive gyroscopes can detect changes in the magnetic field through tunnel magnetoresistive devices, thereby measuring angular velocity. The magnetic field generating electrodes in the tunnel magnetoresistive gyroscope will generate a magnetic field after power is applied. The electrodes are located on the mass block. The displacement of the mass block will cause changes in the magnetic field distribution. The tunnel magnetoresistive device can detect changes in the magnetic field and thus measure the angular velocity. Compared with conventional capacitive and piezoresistive gyroscopes, tunnel magnetoresistive gyroscopes have the advantages of small size, low energy consumption, and high sensitivity.

[0003] The magnetic field generating electrodes used in conventional tunnel magnetoresistive gyroscopes are of a folded type, similar to several resistors winding in series. Since the entire electrode is connected in series, when one part of the electrode is damaged, the entire magnetic field generating electrode will fail. And because the magnetic field generating electrode is thin and long, its resistance is high, so it generates severe heat and passively becomes a heating resistor. Excessive heating of the magnetic field generating electrode will cause aging of the electrode itself, making the device less reliable, and will also cause thermal stress in the mechanical structure of the inertial sensor, causing increased noise and reducing the signal-to-noise ratio of the sensor. And when the size of the silicon micro inertial device is reduced, the size of the magnetic field generating electrode will also shrink, the heating problem will become more serious, and the reliability will be reduced, resulting in the device size of the tunnel magnetoresistive silicon micro gyroscope being larger and unable to be further reduced. Summary of the invention

[0004] In view of this, the present invention provides a tunnel magnetoresistance gyroscope and a preparation method thereof to solve the problems in the related art of low reliability of the magnetic field generating electrode of the tunnel magnetoresistance gyroscope, severe heat generation leading to electrode aging, increased noise, reduced signal-to-noise ratio, and limited further miniaturization of the device size.

[0005] In a first aspect, the present invention provides a tunnel magnetoresistive gyroscope, the tunnel magnetoresistive gyroscope comprising:

[0006] substrate;

[0007] A magnetic field generating electrode is located on one side surface of the substrate; the magnetic field generating electrode includes a first tuning fork electrode and a second tuning fork electrode; the first tuning fork electrode includes a first bus electrode and a plurality of first parallel electrodes; the first bus electrode is connected to the first end of each first parallel electrode; the second tuning fork electrode includes a second bus electrode and a plurality of second parallel electrodes; the second bus electrode is connected to the first end of each second parallel electrode; the first parallel electrodes and the second parallel electrodes are arranged in an alternating manner; the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes;

[0008] A first metal bump is located on a surface of the first bus electrode facing away from the substrate; the first metal bump is connected to the first bus electrode; the first metal bump is suitable for connecting to an external power source;

[0009] A plurality of second metal bumps are located on a surface of a side of the second end of each second parallel electrode facing away from the substrate; the second metal bumps are connected to the second ends of the second parallel electrodes; and the second metal bumps are suitable for connecting to an external power source.

[0010] The tunnel magnetoresistance gyroscope provided by the present invention, on the one hand, the first parallel electrode and the second parallel electrode are arranged at an interlaced interval, and the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes; the series-parallel design in the magnetic field generating electrode can be realized, thereby realizing a larger current with a lower total voltage, thereby enhancing the magnetic field strength generated by the magnetic field generating electrode and improving the sensitivity and accuracy of magnetic field detection; even if some branch parallel electrodes are disconnected, the overall magnetic field generating electrode can still play a role, thereby improving the reliability of the tunnel magnetoresistance gyroscope; on the other hand, the first metal bump is connected to the first bus electrode, and the second metal bump is connected to the second end of the second parallel electrode, the current directions in adjacent parallel electrodes are opposite, and the magnetic fields of adjacent parallel electrodes along the detection direction cancel each other, so that a larger gradient magnetic field change can be generated in the detection direction, and the magnetic field gradient change in the magnetic field detection direction can be enhanced, which can further increase the magnetic field detection accuracy and sensitivity of the tunnel magnetoresistance gyroscope. Therefore, the tunnel magnetoresistance gyroscope provided by the present invention can enhance the magnetic field strength generated by the magnetic field generating electrode, thereby improving the sensitivity and accuracy of magnetic field detection, and at the same time can improve the reliability and magnetic field detection accuracy of the tunnel magnetoresistance gyroscope.

[0011] In an optional embodiment, the first tuning fork electrode is connected in series with the second tuning fork electrode;

[0012] A plurality of first parallel electrodes are connected in parallel, and a plurality of second parallel electrodes are connected in parallel;

[0013] The directions of currents passing through any first parallel electrode and the adjacent second parallel electrode are opposite;

[0014] Any second parallel electrode is suitable for passing current in a direction opposite to that of the adjacent first parallel electrode.

[0015] In the tunnel magnetoresistive gyroscope provided by the present invention, the first tuning fork electrode is connected in series with the second tuning fork electrode; a plurality of first parallel electrodes are connected in parallel, and a plurality of second parallel electrodes are connected in parallel, so that a larger current can be achieved with a lower total voltage, thereby enhancing the magnetic field strength generated by the magnetic field generating electrode and improving the sensitivity and accuracy of magnetic field detection; even if individual parallel electrodes are disconnected, the magnetic field generating electrode as a whole can still function, thereby improving the reliability of the tunnel magnetoresistive gyroscope. In addition, the series-parallel structural design can achieve a larger current with a lower total voltage, thereby enhancing the magnetic field strength generated by the electrode and improving the accuracy of magnetic field detection.

[0016] In an optional embodiment, the magnetic field generating electrode generates a magnetic field after being energized;

[0017] The length direction of the first parallel electrode is the driving direction of the magnetic field generating electrode;

[0018] The length direction of the first bus electrode is the magnetic field detection direction of the magnetic field generating electrode;

[0019] The area between the first parallel electrode and the adjacent second parallel electrode is the first magnetic field area;

[0020] The position where the first parallel electrode is located and the position where the second parallel electrode is located are the second magnetic field region; in the magnetic field detection direction, the first magnetic field region and the second magnetic field region are alternately arranged;

[0021] The magnetic field strengths at different positions within the effective detection range of the tunnel magnetoresistive gyroscope in the driving direction are the same; a magnetic field strength with a gradient is generated in the magnetic field detection direction; in the magnetic field detection direction, the magnetic field strength of the first magnetic field region is less than the magnetic field strength of the second magnetic field region;

[0022] The tunnel magnetoresistance gyroscope provided by the present invention generates a magnetic field after the magnetic field generating electrode is energized; the length direction of the first parallel electrode is the driving direction of the magnetic field generating electrode, and the magnetic field strengths at different positions within the effective detection range of the tunnel magnetoresistance gyroscope in the driving direction are the same; the length direction of the first bus electrode is the magnetic field detection direction of the magnetic field generating electrode, the area between the first parallel electrode and the adjacent second parallel electrode is the first magnetic field area, and the position where the first parallel electrode is located and the position where the second parallel electrode is located are the second magnetic field area. Since the currents between the adjacent parallel electrodes are opposite, the magnetic fields generated by the parallel electrodes on both sides of the first magnetic field area in the magnetic field detection direction are opposite in direction and cancel each other out, so that the magnetic field strength of the first magnetic field area in the magnetic field detection direction is very small and close to 0; and in the magnetic field detection direction, the magnetic field strength of the first magnetic field area is smaller than that of the second magnetic field area. Since the first magnetic field area and the second magnetic field area are alternately arranged, a magnetic field strength with a gradient can be generated in the magnetic field detection direction, and the magnetic field gradient change in the magnetic field detection direction is enhanced, thereby improving the magnetic field detection accuracy of the tunnel magnetoresistance gyroscope. And within a certain current range, when the current is larger, the magnetic field intensity generated is higher, and the magnetic field gradient change in the detection direction is larger, which is conducive to further increasing the magnetic field detection accuracy of the tunnel magnetoresistive gyroscope.

[0023] In an optional implementation, the tunnel magnetoresistive gyroscope further includes:

[0024] The heat-conducting medium layer is located between the substrate and the magnetic field generating electrode, and the heat-conducting medium layer also covers the side surface of the magnetic field generating electrode.

[0025] The tunnel magnetoresistance gyroscope provided by the present invention, by arranging a heat-conducting medium layer between the substrate and the magnetic field generating electrode, the heat-conducting medium layer also covers the side of the magnetic field generating electrode, and can utilize the high thermal conductivity of the heat-conducting medium layer to achieve three-dimensional heat dissipation of the magnetic field generating electrode, which can not only improve the life of the magnetic field generating electrode but also reduce the influence of thermal stress on the gyroscope, thereby improving the reliability of the tunnel magnetoresistance gyroscope, and is also conducive to further reducing the size of the tunnel magnetoresistance gyroscope; in addition, the heat-conducting medium layer can also reduce noise and improve the measurement accuracy and quality factor of the tunnel magnetoresistance gyroscope.

[0026] In an optional implementation, the tunnel magnetoresistive gyroscope further includes: a dielectric layer located on a surface of the magnetic field generating electrode facing away from the substrate, the dielectric layer covering the side surfaces of the first metal bump and the second metal bump;

[0027] A third metal bump is located on a surface of the second bus electrode facing away from the substrate; the third metal bump is connected to the second bus electrode; the shape and size of the third metal bump are the same as those of the first metal bump;

[0028] A plurality of fourth metal bumps are located on a surface of a side of the second end of each first parallel electrode facing away from the substrate; the fourth metal bump is located at a position symmetrical to the second metal bump relative to the center line of the magnetic field generating electrode; the shape and size of the fourth metal bump are the same as the shape and size of the second metal bump; the dielectric layer also covers the side surfaces of the third metal bump and the fourth metal bump.

[0029] The tunnel magnetoresistance gyroscope provided by the present invention can improve the stability and reliability of the magnetic field generating electrode by setting a dielectric layer; and by setting a third metal bump and a fourth metal bump, they can be counterweighted with the first metal bump and the second metal bump to ensure the weight balance of the gyroscope device, thereby improving the measurement accuracy and quality factor of the tunnel magnetoresistance gyroscope.

[0030] In an optional embodiment, the thermal conductivity of the heat-conducting medium layer is greater than 300 W / m·K.

[0031] In an optional implementation, the material of the thermal conductive medium layer includes diamond or boron nitride.

[0032] In a second aspect, the present invention provides a method for preparing a tunnel magnetoresistive gyroscope, which is used to prepare the tunnel magnetoresistive gyroscope of the first aspect, and the preparation method comprises:

[0033] providing a substrate;

[0034] A magnetic field generating electrode is formed on the surface of one side of the substrate; the magnetic field generating electrode includes a first tuning fork electrode and a second tuning fork electrode; the first tuning fork electrode includes a first bus electrode and a plurality of first parallel electrodes; the first bus electrode is connected to the first end of each first parallel electrode; the second tuning fork electrode includes a second bus electrode and a plurality of second parallel electrodes; the second bus electrode is connected to the first end of each second parallel electrode; the first parallel electrodes and the second parallel electrodes are arranged alternately and spaced apart; the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes;

[0035] A first metal bump and a plurality of second metal bumps are formed on a surface of the magnetic field generating electrode facing away from the substrate; the first metal bump is located on a surface of the first bus electrode facing away from the substrate; the first metal bump is connected to the first bus electrode; the first metal bump is suitable for connecting to an external power supply; the second metal bump is located on a surface of the second end of each second parallel electrode facing away from the substrate; the second metal bump is connected to the second end of the second parallel electrode; the second metal bump is suitable for connecting to an external power supply.

[0036] In an optional embodiment, before the step of forming a magnetic field generating electrode on one surface of the substrate, the method further includes:

[0037] forming a thermally conductive medium layer between the surfaces of one side of the substrate;

[0038] The step of forming a magnetic field generating electrode on a surface of one side of the substrate comprises:

[0039] Etching the heat-conducting medium layer to form a first patterned groove; the first patterned groove penetrates into a portion of the heat-conducting medium layer;

[0040] A first patterned metal is deposited in the first patterned groove to form a magnetic field generating electrode; and the remaining heat conductive medium layer covers the bottom surface and side surfaces of the magnetic field generating electrode.

[0041] In an optional embodiment, the step of forming a first metal bump and a plurality of second metal bumps on a surface of the magnetic field generating electrode facing away from the substrate includes:

[0042] forming a dielectric layer on a surface of the magnetic field generating electrode facing away from the substrate;

[0043] Etching the dielectric layer to form a second patterned groove; the second patterned groove penetrates the dielectric layer;

[0044] A second patterned metal is deposited in the second patterned groove to form a first metal bump and a plurality of second metal bumps; and the remaining dielectric layer covers the side surfaces of the first metal bump and the side surfaces of the second metal bump. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 1 is a schematic top view of a magnetic field generating electrode in a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0047] Figure 2 Schematic diagram of the structure of a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0048] Figure 3 Schematic diagram of the circuit structure of a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0049] Figure 4 The figure is a schematic diagram of magnetic field distribution of magnetic field generating electrodes in a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0050] Figure 5 The present invention is a schematic diagram of the change of magnetic field intensity of a magnetic field generating electrode in a tunnel magnetoresistive gyroscope in a driving direction and a magnetic field detection direction according to an embodiment of the present invention.

[0051] Figure 6 It is a schematic flow chart of a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0052] Figure 7 It is a structural schematic diagram of forming a heat-conducting medium layer in a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0053] Figure 8 It is a structural schematic diagram of forming a magnetic field generating electrode in a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0054] Fig. 9 In a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention, Figure 8 Schematic diagram of the structure of forming a dielectric layer on the basis.

[0055] Fig.10 In a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention, Fig. 9 A schematic structural diagram of a first metal bump, a second metal bump, a third metal bump and a fourth metal bump are formed on the basis.

[0056] Fig.11 It is a schematic diagram of a specific process of a method for preparing a tunnel magnetoresistive gyroscope according to an embodiment of the present invention.

[0057] Reference numerals:

[0058] 1. Substrate; 2. Thermal conductive medium layer; 3. Magnetic field generating electrode; 31. First tuning fork electrode; 311. First bus electrode; 312. First parallel electrode; 32. Second tuning fork electrode; 321. Second bus electrode; 322. Second parallel electrode; 4. Dielectric layer; 51. First metal bump; 52. Second metal bump; 53. Third metal bump; 54. Fourth metal bump. DETAILED DESCRIPTION

[0059] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0060] In the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified for the purpose of clear expression, and some details may be omitted. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships between them are only exemplary, and may be deviated due to manufacturing tolerances or technical limitations in practice, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be a middle layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element.

[0061] Gyroscopes are important inertial sensor devices commonly used in daily life and production. Conventional gyroscopes work by using capacitance and piezoresistive detection effects, but capacitance and piezoresistive detection effects are limited by issues such as interface resolution and process processing, which limits the measurement resolution. Tunnel magnetoresistive gyroscopes can detect changes in the magnetic field through tunnel magnetoresistive devices, and then measure angular velocity. Specifically, the magnetic field generating electrodes in the tunnel magnetoresistive gyroscope will generate a magnetic field after being energized. The electrodes are located on the mass block, and the displacement of the mass block will cause changes in the magnetic field distribution. The tunnel magnetoresistive device can detect changes in the magnetic field, thereby measuring the angular velocity. Compared with conventional capacitive and piezoresistive gyroscopes, tunnel magnetoresistive gyroscopes have the advantages of small size, low energy consumption, and high sensitivity.

[0062] The magnetic field generating electrodes used in conventional tunnel magnetoresistive gyroscopes are of a folded type, similar to several resistors winding in series. Since the entire electrode is connected in series, when one part of the electrode is damaged, the entire magnetic field generating electrode will fail. And because the magnetic field generating electrode is thin and long, its resistance is high, so it generates severe heat and passively becomes a heating resistor. Excessive heating of the magnetic field generating electrode will cause aging of the electrode itself, making the device less reliable, and will also cause thermal stress in the mechanical structure of the inertial sensor, causing increased noise and reducing the signal-to-noise ratio of the sensor. And when the size of the silicon micro inertial device is reduced, the size of the magnetic field generating electrode will also shrink, the heating problem will become more serious, and the reliability will be reduced, resulting in the device size of the tunnel magnetoresistive silicon micro gyroscope being larger and unable to be further reduced.

[0063] like Figure 1 As shown, this embodiment provides a tunnel magnetoresistive gyroscope, and the tunnel magnetoresistive gyroscope includes:

[0064] Substrate 1;

[0065] The magnetic field generating electrode 3 is located on one side surface of the substrate 1; the magnetic field generating electrode 3 includes a first tuning fork electrode 31 and a second tuning fork electrode 32; the first tuning fork electrode 31 includes a first bus electrode 311 and a plurality of first parallel electrodes 312; the first bus electrode 311 is connected to the first end of each first parallel electrode 312; the second tuning fork electrode 32 includes a second bus electrode 321 and a plurality of second parallel electrodes 322; the second bus electrode 321 is connected to the first end of each second parallel electrode 322; the first parallel electrodes 312 and the second parallel electrodes 322 are arranged in an alternating manner; the second end of each first parallel electrode 312 is connected to the first bus electrode 311 between two adjacent second parallel electrodes 322;

[0066] The first metal bump 51 is located on a surface of the first bus electrode 311 facing away from the substrate 1 ; the first metal bump 51 is connected to the first bus electrode 311 ; the first metal bump 51 is suitable for connecting to an external power source;

[0067] A plurality of second metal bumps 52 are located on a surface of the second end N2 of each second parallel electrode 322 facing away from the substrate 1 ; the second metal bump 52 is connected to the second end N2 of the second parallel electrode 322 ; the second metal bump 52 is suitable for connecting to an external power source.

[0068] The tunnel magnetoresistance gyroscope provided in this embodiment, on the one hand, the first parallel electrodes and the second parallel electrodes are arranged at staggered intervals, and the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes; the series-parallel design in the magnetic field generating electrode can be realized, thereby realizing a larger current with a lower total voltage, thereby enhancing the magnetic field strength generated by the magnetic field generating electrode and improving the sensitivity and accuracy of magnetic field detection; even if some branch parallel electrodes are disconnected, the overall magnetic field generating electrode can still function, thereby improving the reliability of the tunnel magnetoresistance gyroscope; on the other hand, the first metal bump is connected to the first bus electrode, and the second metal bump is connected to the second end of the second parallel electrode. The current directions of adjacent parallel electrodes are opposite, and the magnetic fields generated in the magnetic field detection direction offset each other, which can enhance the magnetic field gradient change in the detection direction, thereby increasing the magnetic field detection accuracy of the tunnel magnetoresistance gyroscope. Therefore, the tunnel magnetoresistance gyroscope provided in this embodiment can enhance the magnetic field strength generated by the magnetic field generating electrode, thereby improving the sensitivity and accuracy of magnetic field detection, and at the same time can improve the reliability and magnetic field detection accuracy of the tunnel magnetoresistance gyroscope.

[0069] In some optional embodiments, such as Figure 3 As shown, the first tuning fork electrode 31 is connected in series with the second tuning fork electrode 32;

[0070] The plurality of first parallel electrodes 312 are connected in parallel, and the plurality of second parallel electrodes 322 are connected in parallel;

[0071] The directions of currents passing through any first parallel electrode 312 and the adjacent second parallel electrode 322 are opposite;

[0072] Any second parallel electrode 322 is suitable for passing current in the opposite direction to the adjacent first parallel electrode 312;

[0073] The magnitude of the current that the first parallel electrodes 312 and the magnitude of the current that the second parallel electrodes 322 are suitable for passing is 2 mA to 200 mA.

[0074] In a specific implementation, the connection positions of the first metal bump 51 and the second metal bump 52 and the magnetic field generating electrode 3 are as follows: Figure 4 As shown, the magnetic field generating electrodes are connected to the positive and negative electrodes to form a circuit diagram as shown in Figure 3 As shown, the first parallel electrodes 312 and the second parallel electrodes 322 exist as resistors in the circuit, multiple first parallel electrodes 312 are connected in parallel, and multiple second parallel electrodes 322 are connected in parallel; the first tuning fork electrode 31 and the second tuning fork electrode 32 are connected in series to form an interlaced magnetic field generating electrode 3.

[0075] In the tunnel magnetoresistive gyroscope provided in this embodiment, the first tuning fork electrode is connected in series with the second tuning fork electrode; multiple first parallel electrodes are connected in parallel, and multiple second parallel electrodes are connected in parallel, so that a larger current can be achieved with a lower total voltage, thereby enhancing the magnetic field strength generated by the magnetic field generating electrode and improving the sensitivity and accuracy of magnetic field detection; even if individual parallel electrodes are disconnected, the magnetic field generating electrode as a whole can still function, thereby improving the reliability of the tunnel magnetoresistive gyroscope. In addition, the series-parallel structural design can achieve a larger current with a lower total voltage, thereby enhancing the magnetic field strength generated by the electrode and improving the accuracy of magnetic field detection.

[0076] In some optional embodiments, such as Figure 4 As shown, the magnetic field generating electrode 3 generates a magnetic field after being energized;

[0077] The length direction of the first parallel electrode 312 is the driving direction of the magnetic field generating electrode 3;

[0078] The length direction of the first bus electrode 311 is the magnetic field detection direction of the magnetic field generating electrode 3;

[0079] The area between the first parallel electrode 312 and the adjacent second parallel electrode 322 is the first magnetic field area A;

[0080] The position where the first parallel electrode 312 and the position where the second parallel electrode 322 are located are the second magnetic field region B; in the magnetic field detection direction, the first magnetic field region and the second magnetic field region are alternately arranged;

[0081] The magnetic field strength at different positions in the effective detection range of the tunnel magnetoresistive gyroscope is the same at different positions in the driving direction; a gradient magnetic field strength is generated in the magnetic field detection direction, such as Figure 5 As shown; in the magnetic field detection direction, the magnetic field strength of the first magnetic field region is less than the magnetic field strength of the second magnetic field region.

[0082] When it comes to specific implementation, Figure 4 The arrow in the figure is the direction of the current, and the cross and dot on both sides of the electrode represent the direction of the magnetic field entering and exiting the paper vertically. The magnetic fields generated by adjacent parallel electrodes in the direction of magnetic field detection cancel each other out, enhancing the change of magnetic field gradient in one direction, which is beneficial to increase the accuracy of magnetic field detection. Within a certain range, as the branch current increases, the greater the change of magnetic field gradient in the direction of magnetic field detection, the higher the sensitivity and accuracy of magnetic field detection. Figure 5 The magnetic field distribution of the magnetic field generating electrode along the magnetic field detection direction and the driving direction is uniform, and the magnetic field distribution along the magnetic field detection direction has a significant gradient change. The first magnetic field region A and the second magnetic field region B are the low point and the high point of the magnetic field intensity respectively.

[0083] In specific implementation, the tunnel magnetoresistive gyroscope measures the angular velocity by measuring the Coriolis force generated by the mass block. The mass block must continuously move in the driving direction. The driving direction of the magnetic field generating electrode 3 refers to the driving direction of the mass block.

[0084] The tunnel magnetoresistance gyroscope provided in the present embodiment generates a magnetic field after the magnetic field generating electrode is energized; the length direction of the first parallel electrode is the driving direction of the magnetic field generating electrode, and the magnetic field strength in the driving direction at different positions within the effective detection range of the tunnel magnetoresistance gyroscope is the same; the length direction of the first bus electrode is the magnetic field detection direction of the magnetic field generating electrode, the area between the first parallel electrode and the adjacent second parallel electrode is the first magnetic field area, and the position where the first parallel electrode is located and the position where the second parallel electrode is located are the second magnetic field area. Since the currents between the adjacent parallel electrodes are opposite, the magnetic fields generated by the parallel electrodes on both sides of the first magnetic field area in the magnetic field detection direction are opposite in direction and cancel each other out, so that the magnetic field strength of the first magnetic field area in the magnetic field detection direction is very small and close to 0; and in the magnetic field detection direction, the magnetic field strength of the first magnetic field area is less than that of the second magnetic field area. Since the first magnetic field area and the second magnetic field area are alternately arranged, a magnetic field strength with a gradient can be generated in the magnetic field detection direction, and the magnetic field gradient change in the magnetic field detection direction is enhanced, thereby improving the magnetic field detection accuracy of the tunnel magnetoresistance gyroscope. And within a certain current range, when the current is larger, the magnetic field intensity generated is higher, and the magnetic field gradient change in the detection direction is larger, which is conducive to further increasing the magnetic field detection accuracy of the tunnel magnetoresistive gyroscope.

[0085] In some optional embodiments, in the direction of magnetic field detection, the magnetic field strength of the first magnetic field region is related to the magnetic field strength of the second magnetic field region and the specific value of the current, the different positions of the coil, the parallel electrode spacing and other factors, and the specific value is not limited in this embodiment. In a specific example, when the current is 200mA, at a height of 10μm from the coil, the magnetic field strength of the first magnetic field region A is 0.0005T, and the magnetic field strength of the second magnetic field region B is 0.004T, thereby generating a gradient magnetic field strength in the direction of magnetic field detection, with the low point of the gradient being about 0.0005T and the high point being 0.004T.

[0086] In some optional embodiments, such as Figure 2 As shown, the tunnel magnetoresistive gyroscope also includes:

[0087] The heat-conducting medium layer 2 is located between the substrate 1 and the magnetic field generating electrode 3 , and the heat-conducting medium layer 2 also covers the side surface of the magnetic field generating electrode 3 .

[0088] When it comes to specific implementation, Figure 2 for Figure 1 Schematic diagram of the cross section in direction ①.

[0089] The tunnel magnetoresistance gyroscope provided in this embodiment, by arranging a heat-conducting medium layer between the substrate and the magnetic field generating electrode, the heat-conducting medium layer also covers the side of the magnetic field generating electrode, and can use the high thermal conductivity of the heat-conducting medium layer to achieve three-dimensional heat dissipation of the magnetic field generating electrode, which can not only improve the life of the magnetic field generating electrode but also reduce the influence of thermal stress on the accuracy of the gyroscope, thereby improving the reliability of the tunnel magnetoresistance gyroscope, and is also conducive to further reducing the size of the tunnel magnetoresistance gyroscope; in addition, the heat-conducting medium layer can also reduce noise and improve the measurement accuracy and quality factor of the tunnel magnetoresistance gyroscope.

[0090] In some optional embodiments, the tunnel magnetoresistive gyroscope further includes: a dielectric layer 4, located on a surface of the magnetic field generating electrode 3 facing away from the substrate 1, the dielectric layer 4 covering the side surfaces of the first metal bump 51 and the second metal bump 52;

[0091] The third metal bump 53 is located on the surface of the second bus electrode 321 facing away from the substrate 1 ; the third metal bump 53 is connected to the second bus electrode 321 ; the shape and size of the third metal bump 53 are the same as those of the first metal bump 51 ;

[0092] A plurality of fourth metal bumps 54 are located on a surface of a side of the second end of each first parallel electrode 312 facing away from the substrate 1; the fourth metal bump 54 is located at a position symmetrical to the second metal bump 52 relative to the center line of the magnetic field generating electrode 3; the shape and size of the fourth metal bump 54 are the same as those of the second metal bump 52; the dielectric layer 4 also covers the side surfaces of the third metal bump 53 and the fourth metal bump 54.

[0093] During specific implementation, the third metal bump and the fourth metal bump are only used for balancing weights and are not connected to the positive and negative electrodes of the power supply.

[0094] The tunnel magnetoresistance gyroscope provided in this embodiment can improve the stability and reliability of the magnetic field generating electrode by setting a dielectric layer; by setting a third metal bump and a fourth metal bump, they can be counterweighted with the first metal bump and the second metal bump to ensure the weight balance of the gyroscope device, thereby improving the measurement accuracy and quality factor of the tunnel magnetoresistance gyroscope.

[0095] In some optional embodiments, the thermal conductivity of the heat-conducting medium layer 2 is greater than 300 W / m·K.

[0096] In some optional embodiments, the material of the thermal conductive medium layer 2 includes diamond or boron nitride.

[0097] In some optional embodiments, the material of the substrate 1 is silicon; the material of the magnetic field generating electrode 3 is copper;

[0098] The length and width of the magnetic field generating electrode 3 are 850 μm to 1050 μm, for example, 850 μm, 900 μm, 950 μm, 1000 μm and 1050 μm;

[0099] The width of the first parallel electrodes 312 is 2 μm to 20 μm, for example, 2 μm, 5 μm, 10 μm, 15 μm and 20 μm, and the length of the first parallel electrodes 312 is 800 μm to 1000 μm, for example, 800 μm, 850 μm, 900 μm, 950 μm and 1000 μm; the thickness of the first parallel electrodes 312 is 1 μm to 9 μm, for example, 1 μm, 3 μm, 5 μm, 7 μm and 9 μm;

[0100] The width of the second parallel electrodes 322 is 5 μm to 20 μm, the length of the second parallel electrodes 322 is 795 μm to 995 μm, for example, 795 μm, 845 μm, 895 μm, 945 μm and 995 μm, and the thickness of the second parallel electrodes 322 is 1 μm to 9 μm, for example, 1 μm, 3 μm, 5 μm, 7 μm and 9 μm;

[0101] The material of the first metal bump 51 and the second metal bump 52 is copper;

[0102] The thickness of the first metal bump 51 and the second metal bump 52 is 0.3 μm to 1 μm, for example, 0.3 μm, 0.5 μm, 0.7 μm, 0.9 μm and 1 μm.

[0103] In some optional embodiments, the thickness of the thermal conductive medium layer 2 is 2 μm to 10 μm, for example, 2 μm, 4 μm, 6 μm, 8 μm and 10 μm;

[0104] The material of the dielectric layer 4 is aluminum oxide;

[0105] The thickness of the dielectric layer 4 is 0.2 μm to 0.8 μm, for example, 0.2 μm, 0.4 μm, 0.5 μm, 0.6 μm and 0.8 μm;

[0106] The material of the third metal bump 53 and the fourth metal bump 54 is copper;

[0107] The thickness of the third metal bump 53 and the fourth metal bump 54 is 0.3 μm to 1 μm, for example, 0.3 μm, 0.5 μm, 0.7 μm, 0.9 μm and 1 μm.

[0108] like Figure 6 As shown, this embodiment provides a method for preparing a tunnel magnetoresistive gyroscope, and the preparation method includes but is not limited to steps S101 to S106.

[0109] Step S101, providing a substrate 1;

[0110] Step S102, forming a magnetic field generating electrode 3 on the surface of one side of the substrate 1; the magnetic field generating electrode 3 includes a first tuning fork electrode 31 and a second tuning fork electrode 32; the first tuning fork electrode 31 includes a first bus electrode 311 and a plurality of first parallel electrodes 312; the first bus electrode 311 is connected to a first end M1 of each first parallel electrode 312; the second tuning fork electrode 32 includes a second bus electrode 321 and a plurality of second parallel electrodes 322; the second bus electrode 321 is connected to a first end N1 of each second parallel electrode 322; the first parallel electrodes 312 and the second parallel electrodes 322 are arranged in an alternating manner; the second end M2 of each first parallel electrode 312 is connected to the first bus electrode 311 between two adjacent second parallel electrodes 322;

[0111] Step S103, forming a first metal bump 51 and a plurality of second metal bumps 52 on the side surface of the magnetic field generating electrode 3 facing away from the substrate 1; the first metal bump 51 is located on the side surface of the first bus electrode 311 facing away from the substrate 1; the first metal bump 51 is connected to the first bus electrode 311; the first metal bump 51 is suitable for connecting to an external power supply; the second metal bump 52 is located on the side surface of the second end N2 of each second parallel electrode 322 facing away from the substrate 1; the second metal bump 52 is connected to the second end N2 of the second parallel electrode 322; the second metal bump 52 is suitable for connecting to an external power supply.

[0112] In an optional embodiment, before the step of forming a magnetic field generating electrode on one side surface of the substrate 1, the method further includes:

[0113] A heat conducting medium layer 2 is formed on one side of the substrate 1. Figure 7 As shown;

[0114] The step of forming a magnetic field generating electrode 3 on one side surface of the substrate 1 includes:

[0115] Etching the heat-conducting medium layer 2 to form a first patterned groove; the first patterned groove penetrates into a portion of the heat-conducting medium layer 2;

[0116] A first patterned metal is deposited in the first patterned groove to form a magnetic field generating electrode 3; the remaining thermal conductive medium layer 2 covers the bottom and side surfaces of the magnetic field generating electrode 3, such as Figure 8 shown.

[0117] In an optional embodiment, the step of forming a first metal bump 51 and a plurality of second metal bumps 52 on a surface of the magnetic field generating electrode 33 facing away from the substrate 1 includes:

[0118] A dielectric layer 4 is formed on the surface of the magnetic field generating electrode 3 facing away from the substrate 1. Fig. 9 As shown;

[0119] Etching the dielectric layer 4 to form a second patterned groove; the second patterned groove penetrates the dielectric layer;

[0120] A second patterned metal is deposited in the second patterned groove to form a first metal bump 51 and a second metal bump 52; the remaining dielectric layer 4 covers the side surface of the first metal bump 51 and the side surface of the second metal bump 52, such as Fig.10 shown.

[0121] In an optional embodiment, the step of depositing the second patterned metal in the second patterned groove includes:

[0122] A second patterned metal is deposited in the second patterned groove to form a first metal bump 51, a second metal bump 52, a third metal bump 53 and a fourth metal bump 54; the remaining dielectric layer 4 covers the side surface of the first metal bump 51, the side surface of the second metal bump 52, the side surface of the third metal bump 53 and the fourth metal bump 54, as shown in FIG. Fig.10 shown.

[0123] like Fig.11 The present invention also provides a specific flow chart of a method for preparing a tunnel magnetoresistive gyroscope, which includes the following steps:

[0124] Step S201, providing a substrate 1.

[0125] In a specific implementation, the substrate 1 is a silicon substrate, and the thickness of the silicon substrate is 300 μm to 400 μm.

[0126] Step S202, forming a heat conducting medium layer 2 between one side surface of the substrate 1, such as Figure 7 shown.

[0127] In the specific implementation, the thermal conductive medium layer is a diamond film, and the silicon substrate is roughened with diamond powder. Polishing the substrate is conducive to the nucleation and growth of diamond. Then, ultrasonic cleaning is carried out with acetone, alcohol, isopropanol, and deionized water in turn, and finally the substrate is dried. The deposition of diamond film is divided into two steps, first nucleation and then film growth. The thickness of the diamond film is 2μm to 10μm. The growth temperature of the diamond film is relatively high, about 800°C, and the growth of diamond needs to be completed before the mechanical structure is formed. The diamond film only exists in specific areas, such as the surface of the mass block. The diamond film in other areas, such as the area where the mechanical structure needs to be formed later, needs to be removed by reactive ion etching.

[0128] Step S203 , etching the heat-conducting medium layer 2 to form a first patterned groove; the first patterned groove penetrates part of the heat-conducting medium layer 2 .

[0129] Specifically, nickel is first deposited and patterned on the diamond film as a metal hard mask, and then the diamond film is patterned by reactive ion etching technology to form a first patterned groove, and the nickel metal mask is wet-removed and cleaned.

[0130] Step S204, depositing a first patterned metal in the first patterned groove to form a magnetic field generating electrode 3; the remaining thermal conductive medium layer 2 covers the bottom and side surfaces of the magnetic field generating electrode 3, such as Figure 8As shown; the magnetic field generating electrode 3 includes a first tuning fork electrode 31 and a second tuning fork electrode 32; the first tuning fork electrode 31 includes a first bus electrode 311 and a plurality of first parallel electrodes 312; the first bus electrode 311 is connected to the first end M1 of each first parallel electrode 312; the second tuning fork electrode 32 includes a second bus electrode 321 and a plurality of second parallel electrodes 322; the second bus electrode 321 is connected to the first end N1 of each second parallel electrode 322; the first parallel electrodes 312 and the second parallel electrodes 322 are arranged in an alternating manner; the second end M2 of each first parallel electrode 312 is connected to the first bus electrode 311 between two adjacent second parallel electrodes 322.

[0131] In a specific implementation, copper is deposited in the first patterned groove after cleaning by physical vapor deposition and patterned to form a magnetic field generating electrode. The length and width of the magnetic field generating electrode 3 are 850μm to 1050μm; the width of the first parallel electrode 312 is 2μm to 20μm, the length is 800μm to 1000μm, and the thickness is 1μm to 9μm; the width of the second parallel electrode 322 is 5μm to 20μm, the length is 795μm to 995μm, and the thickness is 1μm to 9μm. Figure 8 As shown, the magnetic field generating electrode 10 is wrapped in the thermal conductive medium layer 2 , and the magnetic field generating electrode 3 is insulated from the substrate 1 .

[0132] Step S205 , forming a dielectric layer 4 on the surface of the magnetic field generating electrode 3 facing away from the substrate 1 .

[0133] Specifically, Fig. 9 As shown, a dielectric layer 4 is formed on the surface of a magnetic field generating electrode 3 wrapped with a diamond film by using a plasma enhanced chemical vapor deposition method. The material of the dielectric layer is aluminum oxide, and the thickness of the dielectric layer 4 is 0.2 μm to 0.8 μm.

[0134] Step S206 , etching the dielectric layer 4 to form a second patterned trench; the second patterned trench penetrates the dielectric layer 4 .

[0135] Step S207, depositing a second patterned metal in the second patterned groove to form a first metal bump 51, a second metal bump 52, a third metal bump 53 and a fourth metal bump 54; the remaining dielectric layer 4 covers the side surface of the first metal bump 51, the side surface of the second metal bump 52, the side surface of the third metal bump 53 and the fourth metal bump 54, as shown in FIG. Fig.10As shown; the first metal bump 51 is located on the side surface of the first bus electrode 311 facing away from the substrate 1; the first metal bump 51 is connected to the first bus electrode 311; the first metal bump 51 is suitable for connecting to an external power source; the second metal bump 52 is located on the side surface of the second end N2 of each second parallel electrode 322 facing away from the substrate 1; the second metal bump 52 is connected to the second end N2 of the second parallel electrode 322; the second metal bump 52 is suitable for connecting to an external power source. The third metal bump 53 is located on the side surface of the second bus electrode 321 facing away from the substrate 1; the third metal bump 53 is connected to the second bus electrode 321; the shape and size of the third metal bump 53 are the same as those of the first metal bump 51; the fourth metal bump 54 is located on the side surface of the second end of each first parallel electrode 312 facing away from the substrate 1; the fourth metal bump 54 is located at a position symmetrical to the second metal bump 52 relative to the center line of the magnetic field generating electrode 3; the shape and size of the fourth metal bump 54 are the same as those of the second metal bump 52.

[0136] When implementing it, Fig.10 As shown, a polymer etching window is formed on the aluminum oxide dielectric layer 11 by photolithography, and then a contact hole corresponding to the metal bump is formed by reactive ion etching, and then the photoresist polymer is removed. Finally, a copper layer is deposited and patterned to form a metal interconnect structure, which includes a first metal bump 51, a second metal bump 52, a third metal bump 53 and a fourth metal bump 54. The thickness of the metal interconnect structure is 0.3μm to 1μm. The first metal bump 51 and the second metal bump 52 are Figure 4 The metal connection points 51 and 52 in the embodiment are connected to the positive and negative electrodes of the external power supply, and the third metal bump 53 and the fourth metal bump 54 only serve as counterweights.

[0137] In the description of this specification, the description with reference to the terms "this embodiment", "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples, unless otherwise clearly and specifically defined. In addition, the terms "first" and "second" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0138] In the above description, the technical details of the patterning and etching of each layer are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. In addition, although the various embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage.

[0139] The above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described above, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the concept of the present invention. The scope of protection of the present invention is determined by the scope of the attached claims.

Claims

1. A tunnel magnetoresistive gyroscope, characterized in that: include: substrate; A magnetic field generating electrode is located on one side surface of the substrate; The magnetic field generating electrode comprises a first tuning fork electrode and a second tuning fork electrode; the first tuning fork electrode comprises a first bus electrode and a plurality of first parallel electrodes; the first bus electrode is connected to the first end of each first parallel electrode; the second tuning fork electrode comprises a second bus electrode and a plurality of second parallel electrodes; the second bus electrode is connected to the first end of each second parallel electrode; the first parallel electrodes and the second parallel electrodes are arranged in an alternating manner; the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes; a first metal bump, located on a surface of the first bus electrode facing away from the substrate; the first metal bump is connected to the first bus electrode; the first metal bump is suitable for connecting to an external power source; A plurality of second metal bumps are located on a surface of a second end of each second parallel electrode facing away from the substrate; the second metal bumps are connected to the second ends of the second parallel electrodes; and the second metal bumps are suitable for connecting to an external power supply.

2. The tunnel magnetoresistive gyroscope according to claim 1, characterized in that: The first tuning fork electrode is connected in series with the second tuning fork electrode; A plurality of the first parallel electrodes are connected in parallel, and a plurality of the second parallel electrodes are connected in parallel; The directions of currents passing through any of the first parallel electrodes and the adjacent second parallel electrodes are opposite; Any second parallel electrode is suitable for passing current in a direction opposite to that of the adjacent first parallel electrode.

3. The tunnel magnetoresistive gyroscope according to claim 2, characterized in that: The magnetic field generating electrode generates a magnetic field after being energized; The length direction of the first parallel electrode is the driving direction of the magnetic field generating electrode; The length direction of the first bus electrode is the magnetic field detection direction of the magnetic field generating electrode; The area between the first parallel electrode and the adjacent second parallel electrode is a first magnetic field area; The positions where the first parallel electrodes are located and the positions where the second parallel electrodes are located are second magnetic field regions; in the magnetic field detection direction, the first magnetic field regions and the second magnetic field regions are alternately arranged; The magnetic field strengths at different positions within the effective detection range of the tunnel magnetoresistive gyroscope are the same in the driving direction; a magnetic field strength with a gradient is generated in the magnetic field detection direction; and in the magnetic field detection direction, the magnetic field strength of the first magnetic field region is less than the magnetic field strength of the second magnetic field region.

4. The tunnel magnetoresistive gyroscope according to claim 1, characterized in that: The tunnel magnetoresistive gyroscope further comprises: The heat-conducting medium layer is located between the substrate and the magnetic field generating electrode, and the heat-conducting medium layer also covers the side surface of the magnetic field generating electrode.

5. The tunnel magnetoresistive gyroscope according to claim 4, characterized in that: The tunnel magnetoresistive gyroscope further comprises: a dielectric layer, located on a surface of the magnetic field generating electrode facing away from the substrate, the dielectric layer covering the side surfaces of the first metal bump and the second metal bump; a third metal bump, located on a surface of the second bus electrode facing away from the substrate; the third metal bump is connected to the second bus electrode; the shape and size of the third metal bump are the same as those of the first metal bump; A plurality of fourth metal bumps are located on a surface of a side of the second end of each of the first parallel electrodes facing away from the substrate; the fourth metal bump is located at a position symmetrical to the second metal bump relative to the center line of the magnetic field generating electrode; the shape and size of the fourth metal bump are the same as the shape and size of the second metal bump; the dielectric layer also covers the side surfaces of the third metal bump and the fourth metal bump.

6. The tunnel magnetoresistive gyroscope according to claim 4, characterized in that: The thermal conductivity of the heat-conducting medium layer is greater than 300 W / m·K.

7. The tunnel magnetoresistive gyroscope according to claim 6, characterized in that: The material of the heat-conducting medium layer includes diamond or boron nitride.

8. A method for preparing a tunnel magnetoresistive gyroscope, for preparing the tunnel magnetoresistive gyroscope as claimed in claim 1, characterized in that: include: providing a substrate; Forming a magnetic field generating electrode on a surface of one side of the substrate; The magnetic field generating electrode comprises a first tuning fork electrode and a second tuning fork electrode; the first tuning fork electrode comprises a first bus electrode and a plurality of first parallel electrodes; the first bus electrode is connected to the first end of each first parallel electrode; the second tuning fork electrode comprises a second bus electrode and a plurality of second parallel electrodes; the second bus electrode is connected to the first end of each second parallel electrode; the first parallel electrodes and the second parallel electrodes are arranged in an alternating manner; the second end of each first parallel electrode is connected to the first bus electrode between two adjacent second parallel electrodes; A first metal bump and a plurality of second metal bumps are formed on a surface of the magnetic field generating electrode facing away from the substrate; the first metal bump is located on a surface of the first bus electrode facing away from the substrate; the first metal bump is connected to the first bus electrode; the first metal bump is suitable for connecting to an external power supply; the second metal bump is located on a surface of the second end of each second parallel electrode facing away from the substrate; the second metal bump is connected to the second end of the second parallel electrode; the second metal bump is suitable for connecting to an external power supply.

9. The method for preparing a tunnel magnetoresistive gyroscope according to claim 8, characterized in that: Before the step of forming a magnetic field generating electrode on the surface of one side of the substrate, the method further comprises: forming a thermally conductive medium layer on a surface of one side of the substrate; The step of forming a magnetic field generating electrode on the surface of one side of the substrate includes: Etching the thermal conductive medium layer to form a first patterned groove; the first patterned groove penetrates into a portion of the thermal conductive medium layer; A first patterned metal is deposited in the first patterned groove to form the magnetic field generating electrode; and the remaining thermal conductive medium layer covers the bottom surface and side surfaces of the magnetic field generating electrode.

10. The method for preparing a tunnel magnetoresistive gyroscope according to claim 9, characterized in that: The step of forming a first metal bump and a plurality of second metal bumps on a surface of the magnetic field generating electrode facing away from the substrate comprises: forming a dielectric layer on a surface of the magnetic field generating electrode facing away from the substrate; Etching the dielectric layer to form a second patterned groove; the second patterned groove penetrates the dielectric layer; A second patterned metal is deposited in the second patterned groove to form the first metal bump and the second metal bump; the remaining dielectric layer covers the side surfaces of the first metal bump and the side surfaces of the second metal bump.

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