Sensor module and vehicle

Abstract

A sensor module and a vehicle, the sensor module including: a package having a first space and a second space overlapping each other when viewed from a first direction; a vibration element and an integrated circuit disposed in the first space; and an MEMS sensor disposed in the second space, the integrated circuit is electrically connected to the vibrating element and the MEMS sensor, and the vibrating element, the integrated circuit, and the MEMS sensor overlap when viewed from the first direction.

Description

Technical Field

[0001] This invention relates to sensor modules and vehicles. Background Technology

[0002] Sensor modules with gyroscope and accelerometer sensors are known to exist.

[0003] For example, Patent Document 1 describes an inertial sensor module comprising: a first sensor with a first axis, a second axis, and a third axis as detection axes; and a second sensor with higher accuracy than the first sensor, and with the third axis as the detection axis. The first and second sensors are disposed on a plane within a package and are hermetically sealed by the package.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2023-50622

[0005] In the inertial sensor module described in Patent Document 1, since the first sensor and the second sensor are arranged on the same plane in the internal space of a package, the dedicated area becomes larger. Summary of the Invention

[0006] One aspect of the sensor module involved in this invention comprises:

[0007] The package has a first space and a second space that overlap when viewed from a first direction;

[0008] Vibration element and integrated circuit, disposed in the first space; and

[0009] MEMS sensors are configured in the second space.

[0010] The integrated circuit is electrically connected to the vibration element and the MEMS sensor.

[0011] When viewed from the first direction, the vibration element, the integrated circuit, and the MEMS sensor overlap.

[0012] One aspect of the vehicle involved in this invention includes the sensor module. Attached Figure Description

[0013] Figure 1 This is a schematic top view of the sensor module involved in this embodiment.

[0014] Figure 2 This is a schematic cross-sectional view of the sensor module involved in this embodiment.

[0015] Figure 3 This is a schematic cross-sectional view of the sensor module involved in this embodiment.

[0016] Figure 4 This is a schematic side view of the substrate of the sensor module involved in this embodiment.

[0017] Figure 5 This is a schematic top view of the MEMS sensor of the sensor module involved in this embodiment.

[0018] Figure 6 This is a schematic cross-sectional view of the MEMS sensor of the sensor module involved in this embodiment.

[0019] Figure 7 This is a schematic cross-sectional view of the triaxial angular velocity sensor of the sensor module involved in this embodiment.

[0020] Figure 8 This is a schematic cross-sectional view of the triaxial accelerometer of the sensor module involved in this embodiment.

[0021] Figure 9 This is a schematic top view illustrating the vibration element of the sensor module involved in this embodiment.

[0022] Figure 10 This is a diagram used to explain the operation of the vibration element of the sensor module involved in this embodiment.

[0023] Figure 11 This is a diagram used to explain the operation of the vibration element of the sensor module involved in this embodiment.

[0024] Figure 12 This is a block diagram used to describe the integrated circuit of the sensor module involved in this embodiment.

[0025] Figure 13 This is a schematic top view of the vehicle involved in this embodiment.

[0026] Explanation of reference numerals in the attached figures

[0027] 2…pad; 4…lead overlap; 10…substrate; 12…base; 14…first terminal; 16…second terminal; 18…conducting portion; 20…package; 22…substrate; 23…flat portion; 24…first wall portion; 25…first recess; 25a…first part; 25b…second part; 26…second wall portion; 27…second recess; 28…cover; 30…MEMS sensor; 31…substrate; 32…lead; 33…molded part; 34…triaxial angular velocity sensor; 34x…X-axis angular velocity sensor element; 34y…Y-axis angular velocity sensor element; 34z…Z-axis angular velocity sensor element; 35…package; 35a…substrate; 35b…cover; 36…triaxial accelerometer; 36x…X-axis accelerometer sensor element; 36y…Y-axis accelerometer sensor element ; 36z…Z-axis acceleration sensor element; 37…Package; 37a…Substrate; 37b…Cover; 38…Circuit element; 38a…Control circuit section; 38b…Interface circuit section; 40…Vibration element; 41…Base; 42, 43…Detection vibration arm; 44, 45…Support arm; 46, 47, 48, 49…Drive vibration arm; 50…Support substrate; 52…Substrate; 53…Opening; 54…Lead wire; 60…Integrated circuit; 62…Control circuit section; 64…Integration processing section; 66…Interface circuit section; 100…Sensor module; 141…First detection signal electrode; 142…First detection ground electrode; 143…Second detection signal electrode; 144…Second detection ground electrode; 145…Drive signal electrode; 146…Drive ground electrode; 200…Vehicle. Detailed Implementation

[0028] The following detailed description of suitable embodiments of the present invention uses the accompanying drawings. It should be noted that the embodiments described below are not intended to unduly limit the scope of the invention as defined in the claims. Furthermore, all configurations described below are not limited to the essential components of the present invention.

[0029] 1. Sensor Module

[0030] 1.1. Overall Composition

[0031] First, the sensor module involved in this embodiment will be described with reference to the accompanying drawings. Figure 1 This is a schematic top view of the sensor module 100 involved in this embodiment. Figure 2 This is an schematic illustration of the sensor module 100 involved in this embodiment. Figure 1 Sectional view along line II-II. Figure 3 This is an schematic illustration of the sensor module 100 involved in this embodiment. Figure 1 Sectional view along line III-III. It should be noted that, in Figures 1-3The diagram illustrates the X-axis, Y-axis, and Z-axis as three mutually orthogonal axes.

[0032] like Figures 1-3 As shown, the sensor module 100 includes, for example, a substrate 10, a package 20, a microelectromechanical systems (MEMS) sensor 30, a vibration element 40, a support substrate 50, and an integrated circuit 60. It should be noted that, for convenience, in... Figure 1 The illustration of the cover 28 of the package 20 is omitted.

[0033] The substrate 10 supports the package 20 and the MEMS sensor 30. The substrate 10 can also be mounted on a mounting substrate (not shown). The substrate 10 has a thickness direction in a first direction. In the illustrated example, the first direction is the Z-axis direction. Hereinafter, the arrow side of the Z-axis direction will be referred to as "upper" and the opposite side as "lower".

[0034] Figure 4 This is a schematic side view of the substrate 10. (As shown) Figure 4 As shown, the substrate 10 includes, for example, a base 12, a first terminal 14, a second terminal 16, and a conductive portion 18. The first terminal 14 is located on one side of the base 12. The second terminal 16 is located on the other side of the base 12. The second terminal 16 is located on the side opposite to the MEMS sensor 30 of the base 12. In the illustrated example, the first terminal 14 is located on the upper surface of the base 12, and the second terminal 16 is located on the lower surface of the base 12. For example, multiple first terminals 14 are provided. For example, multiple second terminals 16 are provided. The first terminal 14 and the second terminal 16 are electrically connected through the conductive portion 18 located on the side of the base 12. When the substrate 10 is mounted on a mounting substrate (not shown), the second terminal 16 is electrically connected to the mounting substrate. The terminals 14, 16, and the conductive portion 18 are made of metals such as copper or gold.

[0035] The substrate 10 is, for example, more flexible than the package 20. Specifically, the base 12 of the substrate 10 is made of a material that is more flexible than the base 22 of the package 20. The substrate 10 can also be a flexible substrate. It should be noted that the substrate 10 is not particularly limited and can also be a ceramic substrate, etc. The substrate 10 may also have a lead frame.

[0036] Package 20 is disposed on substrate 10. Figure 1 In the example shown, package 20 has a shape in which the length in the X-axis direction is greater than the length in the Y-axis direction. For example... Figure 2 and Figure 3 As shown, the package 20 has a base 22 and a cover 28.

[0037] The substrate 22 is made of ceramic, such as alumina. The substrate 22 has, for example, a flat plate portion 23, a first wall portion 24, and a second wall portion 26. In the illustrated example, the substrate 22 has a generally H-shaped form.

[0038] The flat plate portion 23 is disposed between the substrate 10 and the cover 28. The flat plate portion 23 is disposed between the first wall portion 24 and the second wall portion 26. The flat plate portion 23 is flat in shape. In the illustrated example, the flat plate portion 23 is rectangular.

[0039] A first wall portion 24 is provided on the upper surface of the flat plate portion 23. The first wall portion 24 rises upward from the flat plate portion 23. A first recess 25 is formed in the base 22. The first wall portion 24 and the flat plate portion 23 define the first recess 25. The flat plate portion 23 defines the bottom surface of the first recess 25. In the illustrated example, the base 22 has an upwardly opening first recess 25 through the first wall portion 24 and the flat plate portion 23. The first recess 25, for example, when viewed from the Z-axis direction (hereinafter also referred to as "top view"), has a first portion 25a and a second portion 25b that overlap each other. The first portion 25a is located between the cover 28 and the second portion 25b. In top view, the area of ​​the first portion 25a is larger than the area of ​​the second portion 25b. The second portion 25b is provided below the first portion 25a. Through the first portion 25a and the second portion 25b, the base 22 has a stepped first recess 25.

[0040] A second wall portion 26 is provided on the lower surface of the flat plate portion 23. The second wall portion 26 rises downward from the flat plate portion 23. A second recess 27 is formed in the base 22. The second wall portion 26 and the flat plate portion 23 define the second recess 27. The flat plate portion 23 defines the bottom surface of the second recess 27. In the illustrated example, the base 22 has a downwardly opening second recess 27 through the second wall portion 26 and the flat plate portion 23. The second recess 27 opens on the opposite side of the first recess 25.

[0041] The cover 28 is connected to the base 22. The first wall portion 24 has a sealing ring, and the cover 28 can be connected to the sealing ring of the first wall portion 24. The cover 28 can also be fused to the base 22. When the base 22 is made of ceramic, the cover 28 is preferably made of an alloy such as Kova alloy. This reduces the difference in the coefficients of linear expansion between the cover 28 and the base 22.

[0042] The cover 28 closes the first recess 25. Specifically, the cover 28 closes the opening of the first recess 25. The first recess 25 forms a first space 102. The package 20 has the first space 102. The first space 102 is hermetically sealed. The first space 102 is, for example, under reduced pressure, preferably close to a vacuum. This reduces the viscous resistance of the first space 102 and improves the vibration characteristics of the vibrating element 40 disposed in the first space 102. The ambient gas of the first space 102 is not particularly limited.

[0043] The substrate 10 closes the second recess 27. Specifically, the substrate 10 closes the opening of the second recess 27. The second recess 27 forms a second space 104. The package 20 has the second space 104. In top view, the first space 102 and the second space 104 overlap. The second space 104 may or may not be hermetically sealed. However, considering the reduction of moisture intrusion into the MEMS sensor 30 disposed in the second space 104, the second space 104 is preferably hermetically sealed.

[0044] 1.2. MEMS Sensors

[0045] like Figure 2 and Figure 3 As shown, the MEMS sensor 30 is disposed in the second space 104. The MEMS sensor 30 is disposed on the substrate 10 in the second space 104. The MEMS sensor 30 is mounted face down on the substrate 10, for example. Therefore, the MEMS sensor 30 can be directly connected to terminals (not shown) provided on the substrate 10, thus enabling miniaturization of the sensor module 100. It should be noted that, although not shown, as long as the MEMS sensor 30 is disposed in the second space 104, it may not be the substrate 10, but rather a flat plate portion 23 mounted on the base 22.

[0046] Figure 5 This is a schematic top view of the MEMS sensor 30. Figure 6 This is a schematic illustration of the MEMS sensor 30. Figure 5 The VI-VI line cross-sectional view. The MEMS sensor 30 is, for example, a composite sensor for detecting triaxial angular velocity and triaxial acceleration, i.e., a 6DoF sensor.

[0047] like Figure 5 and Figure 6 As shown, the MEMS sensor 30 includes, for example, a substrate 31, a molded part 33, a triaxial angular velocity sensor 34, a triaxial accelerometer 36, and circuit elements 38. It should be noted that, for convenience, in... Figure 5 The illustration of the molded part 33 is omitted in the text.

[0048] The substrate 31 supports a triaxial angular velocity sensor 34, a triaxial accelerometer 36, and circuit elements 38. The substrate 31 has leads 32. For example, multiple leads 32 are provided. Figure 1 In the example shown, a plurality of pads 2 are provided on the substrate 22. The pads 2 are electrically connected to the integrated circuit 60 via lead overlaps 4. The circuit elements 38 of the MEMS sensor 30 are electrically connected to the integrated circuit 60 via leads 32, pads 2, and lead overlaps 4.

[0049] like Figure 6 As shown, the molded component 33 is disposed on the substrate 31. The molded component 33 covers the triaxial angular velocity sensor 34, the triaxial accelerometer 36, and the circuit element 38. The MEMS sensor 30 has a molded structure in which the triaxial angular velocity sensor 34, the triaxial accelerometer 36, and the circuit element 38 are molded and sealed by the molded component 33. It should be noted that, although not shown, the MEMS sensor 30 may not be a molded structure, but rather a packaged structure housed in a ceramic package or the like.

[0050] Figure 7 This schematically illustrates the triaxial angular velocity sensor 34. Figure 5 A sectional view along line VII-VII. The triaxial angular velocity sensor 34 detects the angular velocity ωx about the X-axis, the angular velocity ωy about the Y-axis, and the angular velocity ωz about the Z-axis. (As shown...) Figure 7 As shown, the triaxial angular velocity sensor 34 has an X-axis angular velocity sensor element 34x, a Y-axis angular velocity sensor element 34y, a Z-axis angular velocity sensor element 34z, and a package 35.

[0051] Package 35 houses an X-axis angular velocity sensor element 34x, a Y-axis angular velocity sensor element 34y, and a Z-axis angular velocity sensor element 34z. Package 35 has a base 35a and a cover 35b that closes a recess formed in the base 35a.

[0052] The X-axis angular velocity sensor element 34x, the Y-axis angular velocity sensor element 34y, and the Z-axis angular velocity sensor element 34z are constructed using MEMS. The triaxial angular velocity sensor 34 is formed, for example, by the following steps: forming a substrate 35a from a silicon layer (substrate layer) of an SOI (silicon oninsulator) substrate; forming the angular velocity sensor elements 34x, 34y, and 34z from another silicon layer (device layer); and bonding a cover 35b formed from the silicon substrate to the substrate 35a. Thus, the triaxial angular velocity sensor 34 can be manufactured using silicon semiconductor processes.

[0053] X-axis angular velocity sensor element 34x includes: a fixed comb electrode fixed to a base 35a; a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement relative to the base 35a in the Y-axis and Z-axis directions; and a drive comb electrode for causing the movable comb electrode to vibrate in the Y-axis direction. By energizing the drive comb electrode, the movable comb electrode is placed in a state of vibration in the Y-axis direction (driven vibration state). If an angular velocity ωx about the X-axis is applied to the X-axis angular velocity sensor element 34x, a detection vibration in the Z-axis direction is excited in the movable comb electrode due to the Coriolis force. Based on this detection vibration, the electrostatic capacitance between the fixed and movable comb electrodes changes. Therefore, by extracting this change in electrostatic capacitance as an output signal, the angular velocity ωx can be detected based on the extracted output signal. However, the configuration of the X-axis angular velocity sensor element 34x is not particularly limited as long as it can detect the angular velocity ωx.

[0054] Y-axis angular velocity sensor element 34y includes: a fixed comb electrode fixed to a base 35a; a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement relative to the base 35a in the X-axis and Z-axis directions; and a drive comb electrode for causing the movable comb electrode to vibrate in the X-axis direction. By energizing the drive comb electrode, the movable comb electrode is placed in a state of vibration in the X-axis direction (driven vibration state). If an angular velocity ωy about the Y-axis is applied to the Y-axis angular velocity sensor element 34y, a detection vibration in the Z-axis direction is excited in the movable comb electrode due to the Coriolis force. Based on this detection vibration, the electrostatic capacitance between the fixed and movable comb electrodes changes. Therefore, by extracting this change in electrostatic capacitance as an output signal, the angular velocity ωy can be detected based on the extracted output signal. However, the configuration of the Y-axis angular velocity sensor element 34y is not particularly limited as long as it can detect the angular velocity ωy.

[0055] Z-axis angular velocity sensor element 34z includes: a fixed comb electrode fixed to a base 35a; a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement relative to the base 35a in the X-axis and Y-axis directions; and a driving comb electrode for causing the movable comb electrode to vibrate in the X-axis direction. By energizing the driving comb electrode, the movable comb electrode is placed in a state of vibration in the X-axis direction (driven vibration state). If an angular velocity ωz about the Z-axis is applied to the Z-axis angular velocity sensor element 34z, a detection vibration in the Y-axis direction is excited in the movable comb electrode due to the Coriolis force. Based on this detection vibration, the electrostatic capacitance between the fixed and movable comb electrodes changes. Therefore, by extracting this change in electrostatic capacitance as an output signal, the angular velocity ωz can be detected based on the extracted output signal. However, the configuration of the Z-axis angular velocity sensor element 34z is not particularly limited as long as it can detect the angular velocity ωz.

[0056] It should be noted that the configuration of the triaxial angular velocity sensor 34 is not particularly limited. For example, the substrate 35a and the cover 35b can also be formed of materials other than silicon, such as glass. Furthermore, in the illustrated example, although the angular velocity sensor elements 34x, 34y, and 34z are arranged side-by-side along the Y-axis, this arrangement is not particularly limited. Alternatively, each angular velocity sensor element 34x, 34y, and 34z can be individually packaged in a separate package 320. In this case, the angular velocity sensor elements 34x, 34y, and 34z can be overlapped in the Z-axis direction. Alternatively, two or more angular velocity sensor elements 34x, 34y, and 34z can be selected and integrally formed into a single angular velocity sensor element. In other words, it is also possible to have a configuration that detects two or more of the angular velocities ωx, ωy, and ωz using a single angular velocity sensor element. Furthermore, the configuration is not limited to a triaxial angular velocity sensor 34. The angular velocity detection axis can be two axes or one axis.

[0057] Figure 8 This schematically illustrates the triaxial accelerometer 36. Figure 5 A cross-sectional view along line VIII-VIII. The triaxial accelerometer 36 detects acceleration Ax in the X-axis direction, acceleration Ay in the Y-axis direction, and acceleration Az in the Z-axis direction. (Example...) Figure 8 As shown, the triaxial accelerometer 36 has an X-axis accelerometer element 36x, a Y-axis accelerometer element 36y, a Z-axis accelerometer element 36z, and a package 37.

[0058] Package 37 houses an X-axis accelerometer element 36x, a Y-axis accelerometer element 36y, and a Z-axis accelerometer element 36z. Package 37 has a substrate 37a and a cover 37b that closes a recess formed in the substrate 37a. Accelerometer elements 36x, 36y, and 36z are the same as the aforementioned angular velocity sensor elements 34x, 34y, and 34z, and are constructed using MEMS. The triaxial accelerometer 36 can be manufactured using silicon semiconductor technology.

[0059] X-axis acceleration sensor element 36x includes: a fixed comb electrode fixed to a base 37a; and a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement in the X-axis direction relative to the base 37a. If an acceleration Ax in the X-axis direction is applied to the X-axis acceleration sensor element 36x, the movable comb electrode will displace in the X-axis direction. Consequently, the electrostatic capacitance between the fixed and movable comb electrodes changes according to this displacement. Therefore, by extracting this change in electrostatic capacitance as an output signal, acceleration Ax can be detected based on the extracted output signal. However, the configuration of the X-axis acceleration sensor element 36x is not particularly limited as long as it can detect acceleration Ax.

[0060] Y-axis acceleration sensor element 36y includes: a fixed comb electrode fixed to a base 37a; and a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement in the X-axis direction relative to the base 37a. If an acceleration Ay in the Y-axis direction is applied to the Y-axis acceleration sensor element 36y, the movable comb electrode will displace in the Y-axis direction. Consequently, the electrostatic capacitance between the fixed and movable comb electrodes changes according to this displacement. Therefore, by extracting this change in electrostatic capacitance as an output signal, acceleration Ay can be detected based on the extracted output signal. However, the configuration of the Y-axis acceleration sensor element 36y is not particularly limited as long as it can detect acceleration Ay.

[0061] Z-axis accelerometer element 36z includes: a fixed comb electrode fixed to a base 37a; and a movable comb electrode configured to engage with the fixed comb electrode and capable of displacement in the Z-axis direction relative to the base 37a. If an acceleration Az in the Z-axis direction is applied to the Z-axis accelerometer element 36z, the movable comb electrode will displace in the Z-axis direction. Consequently, the electrostatic capacitance between the fixed and movable comb electrodes changes according to this displacement. Therefore, by extracting this change in electrostatic capacitance as an output signal, the acceleration Az can be detected based on the extracted output signal. However, the configuration of the Z-axis accelerometer element 36z is not particularly limited as long as it can detect the acceleration Az.

[0062] It should be noted that the configuration of the triaxial accelerometer 36 is not particularly limited. For example, the substrate 37a and the cover 37b can also be formed of materials other than silicon, such as glass. Furthermore, in the illustrated example, although the accelerometer elements 36x, 36y, and 36z are arranged side-by-side along the Y-axis, this arrangement is not particularly limited. Alternatively, each accelerometer element 36x, 36y, and 36z can be individually packaged into a single unit 37. In this case, the accelerometer elements 36x, 36y, and 36z can be overlapped in the Z-axis direction. Additionally, two or more accelerometer elements 36x, 36y, and 36z can be integrally formed into a single accelerometer element. In other words, it is also possible to have a configuration that detects two or more of the accelerations Ax, Ay, and Az using a single accelerometer element. Furthermore, the configuration is not limited to a triaxial accelerometer 36; the acceleration detection axis can be two axes or one axis.

[0063] Circuit element 38 is electrically connected to triaxial angular velocity sensor 34 and triaxial accelerometer 36 via substrate 31. Circuit element 38 may be configured, for example, to include a Microcontroller Unit (MCU). Figure 5 As shown, the circuit element 38 includes, for example, a control circuit section 38a that controls the driving of the triaxial angular velocity sensor 34 and the triaxial accelerometer 36; and an interface circuit section 38b that communicates with the integrated circuit 60.

[0064] The control circuit unit 38a controls the drive of the triaxial angular velocity sensor 34, detecting angular velocity ωx based on the output signal of the X-axis angular velocity sensor element 34x, angular velocity ωy based on the output signal of the Y-axis angular velocity sensor element 34y, and angular velocity ωz based on the output signal of the Z-axis angular velocity sensor element 34z. Furthermore, the control circuit unit 38a controls the drive of the triaxial accelerometer 36, detecting acceleration Ax based on the output signal of the X-axis accelerometer sensor element 36x, acceleration Ay based on the output signal of the Y-axis accelerometer sensor element 36y, and acceleration Az based on the output signal of the Z-axis accelerometer sensor element 36z.

[0065] The interface circuit section 38b transmits and receives signals, accepts commands from the integrated circuit 60, or outputs the detected angular velocities ωx, ωy, ωz and accelerations Ax, Ay, Az to the integrated circuit 60. For example, SPI (Serial Peripheral Interface) communication can be used as a communication method between the interface circuit section 38b and the integrated circuit 60. SPI communication is a method suitable for connecting multiple sensors, capable of outputting all signals related to angular velocities ωx, ωy, ωz and accelerations Ax, Ay, Az from a single pin. Therefore, pin reduction of the MEMS sensor 30 can be achieved.

[0066] 1.3. Vibrating Element

[0067] like Figure 2 and Figure 3 As shown, the vibration element 40 is disposed in the first space 102. In the illustrated example, the vibration element 40 is disposed in the first portion 25a of the first recess 25. The vibration element 40 is an angular velocity sensor element for detecting the angular velocity ωz about the Z-axis. The vibration element 40 is a crystal vibration element.

[0068] Figure 9 This is a schematic top view showing the vibrating element 40. (See diagram below.) Figure 9 As shown, the vibration element 40 has: a base 41 located in the center; a pair of detection vibration arms 42 and 43 extending from the base 41 to both sides in the Y-axis direction; a pair of support arms 44 and 45 extending from the base 41 to both sides in the X-axis direction; a pair of drive vibration arms 46 and 47 extending from the front end of one support arm 44 to both sides in the Y-axis direction; and a pair of drive vibration arms 48 and 49 extending from the front end of the other support arm 45 to both sides in the Y-axis direction. The base 41, detection vibration arms 42 and 43, support arms 44 and 45, and drive vibration arms 46, 47, 48, and 49 are integrally formed from a crystal substrate. The vibration element 40 is supported in the base 41 on a support substrate 50.

[0069] Furthermore, the vibration element 40 includes: a first detection signal electrode 141 disposed on the two main surfaces of the detection vibration arm 42; a first detection ground electrode 142 disposed on the two side surfaces of the detection vibration arm 42; a second detection signal electrode 143 disposed on the two main surfaces of the detection vibration arm 43; a second detection ground electrode 144 disposed on the two side surfaces of the detection vibration arm 43; a drive signal electrode 145 disposed on the two main surfaces of the drive vibration arms 46 and 47 and the two side surfaces of the drive vibration arms 48 and 49; and a drive ground electrode 146 disposed on the two side surfaces of the drive vibration arms 46 and 47 and the two main surfaces of the drive vibration arms 48 and 49.

[0070] Figure 10 and Figure 11This is a diagram for explaining the operation of the vibration element 40. It should be noted that for convenience, in Figure 10 and Figure 11 the vibration element 40 is shown in a simplified form.

[0071] As Figure 10 shown, if a drive signal is applied to the drive signal electrode 145, the drive vibrating arms 46, 47 and the drive vibrating arms 48, 49 bend and vibrate in the X-axis direction in an opposite phase manner (hereinafter, this state is also referred to as the "drive vibration mode"). In the drive vibration mode, the vibrations of the drive vibrating arms 46, 47 cancel out the vibrations of the drive vibrating arms 48, 49, and the detection vibrating arms 42, 43 do not substantially vibrate.

[0072] As Figure 11 shown, in the drive vibration mode, if an angular velocity ωz is applied to the vibration element 40, a Coriolis force acts on the drive vibrating arms 46, 47, 48, 49, thereby exciting a bending vibration in the Y-axis direction. Then, the detection vibrating arms 42, 43 bend and vibrate in the X-axis direction (hereinafter, this state is also referred to as the "detection vibration mode") in response to this bending vibration.

[0073] Then, in the detection vibration mode, the charge generated in the detection vibrating arm 42 is taken out as a first detection signal from the first detection signal electrode 141, and the charge generated in the detection vibrating arm 43 is taken out as a second detection signal from the second detection signal electrode 143, and the angular velocity ωz is obtained based on the differential signal of the first detection signal and the second detection signal, that is, the output signal. The frequency-temperature characteristics of a crystal oscillator are more excellent than those of an element composed of silicon MEMS. Therefore, the crystal oscillator, that is, the vibration element 40, can detect the angular velocity ωz with higher accuracy than the Z-axis angular velocity sensor element 34z composed of silicon MEMS.

[0074] When the bias error (output error at rest) of the output signal of the vibration element 40 is set to Bz1 (deg / sec) and the bias error (output error at rest) of the output signal of the Z-axis angular velocity sensor element 34z is set to Bz2 (deg / sec), the relationship Bz1 < Bz2 can be satisfied. Further, it is preferably to satisfy the relationship Bz1 < 0.7Bz2, more preferably to satisfy the relationship Bz1 < 0.5Bz2, and even more preferably to satisfy the relationship Bz1 < 0.3Bz2. By satisfying such a relationship, the vibration element 40 can detect the angular velocity ωz with higher accuracy than the Z-axis angular velocity sensor element 34z.

[0075] The vibrating element 40 is exposed to the first space 102. That is, the vibrating element 40 is disposed in the first space 102 in an exposed state. Therefore, for example, compared to the case where the vibrating element is disposed in the first space in a packaged state, the size of the vibrating element 40 can be increased. As a result, a larger output signal can be obtained, thereby improving the signal-to-noise ratio (S / N). Therefore, the detection accuracy of the angular velocity ωz can be further improved. Furthermore, the larger the size, the smaller the size error, which can effectively suppress the generation of unwanted waves in the driven vibration state. As a result, the bias error of the output signal of the vibrating element 40 can be further reduced. Therefore, the vibrating element 40 can detect the angular velocity ωz with higher accuracy.

[0076] It should be noted that there are no particular limitations on the configuration or structure of the vibration element 40. For example, a silicon MEMS type angular velocity sensor element can also be used as the vibration element 40.

[0077] 1.4.Support substrate

[0078] The support substrate 50 supports the vibrating element 40. Furthermore, the support substrate 50 is electrically connected to the vibrating element 40 and the integrated circuit 60. Figure 2 and Figure 3 As shown, the support substrate 50 is disposed in the first space 102. In the illustrated example, the support substrate 50 is disposed in the first portion 25a of the first recess 25 constituting the first space 102.

[0079] The support substrate 50 is fixed to the base 22 of the package 20. The support substrate 50 is located below the vibrating element 40, supporting the vibrating element 40 from below. By providing the support substrate 50 between the base 22 and the vibrating element 40, it is difficult to apply stress to the vibrating element 40, thereby improving the detection accuracy of the angular velocity of the vibrating element 40. It should be noted that, for convenience, in Figure 1 The simplified diagram of the support substrate 50 is shown in the figure below.

[0080] The support substrate 50 is, for example, a substrate for TAB (Tape Automated Bonding) mounting. Figure 9 As shown, the support substrate 50 includes, for example, a substrate 52 and leads 54 connected to the substrate 52. Figure 3 In the example shown, the substrate 52 is disposed across the stepped portion of the base 22. This stepped portion is formed by the different dimensions of the first portion 25a and the second portion 25b of the first recess 25. For example... Figure 9 As shown, an opening 53 is formed on the substrate 52. The opening 53 extends through the substrate 52 in the Z-axis direction. When viewed from above, the base 41 of the vibrating element 40 overlaps with the opening 53.

[0081] Lead 54 is a bonding lead supporting the vibrating element 40. Lead 54 has a conductive wiring pattern. In the illustrated example, there are six leads 54. Lead 54 extends from the substrate 52 to the center of the opening 53, where the base 41 of the vibrating element 40 is supported. The six leads 54 are electrically connected to the integrated circuit 60. The six leads 54 are electrically connected to the electrodes 141, 142, 143, 144, 145, and 146 of the vibrating element 40.

[0082] It should be noted that the structure of the support substrate 50 is not particularly limited. For example, a crystal plate can be etched to form a frame portion and a beam portion extending from the frame portion to the center of the plate, and the support substrate 50 can be constructed by setting the wiring pattern in the frame portion and the beam portion.

[0083] 1.5. Integrated Circuits

[0084] like Figure 2 and Figure 3 As shown, integrated circuit 60 is disposed in the first space 102. In the illustrated example, integrated circuit 60 is disposed in the second portion 25b of the first recess 25. Integrated circuit 60 is disposed on the flat portion 23 of package 20 in the first space 102.

[0085] When viewed from above, integrated circuit 60 overlaps with vibration element 40 and MEMS sensor 30. Vibration element 40 overlaps with MEMS sensor 30 and integrated circuit 60 when viewed from above. MEMS sensor 30 overlaps with vibration element 40 and integrated circuit 60 when viewed from above. That is, when viewed from above, vibration element 40, integrated circuit 60, and MEMS sensor 30 overlap. Integrated circuit 60 is configured to include an MCU. Integrated circuit 60 is electrically connected to vibration element 40 and MEMS sensor 30.

[0086] Figure 12 This is a block diagram used to illustrate integrated circuit 60. For example... Figure 12 As shown, the integrated circuit 60 includes, for example, a control circuit section 62 for controlling the drive of the vibration element 40; an integrated processing section 64 for correcting the angular error between the Z-axis angular velocity sensor element 34z and the detection axis of the vibration element 40; and an interface circuit section 66 for communicating with external devices.

[0087] The control circuit section 62 controls the drive of the vibration element 40 and detects the angular velocity ωz based on the output signal of the vibration element 40.

[0088] The integrated processing unit 64 corrects the output signal of the vibration element 40 based on the angular error of the detection axis of the vibration element 40 relative to the detection axis of the Z-axis angular velocity sensor element 34z. That is, it aligns and corrects the output signal of the vibration element 40 so that the detection axis of the vibration element 40 is aligned with the detection axis of the Z-axis angular velocity sensor element 34z. As a result, the vibration element 40 can detect the angular velocity about the axis aligned with the detection axis of the Z-axis angular velocity sensor element 34z.

[0089] The interface circuit section 66 transmits and receives signals, accepts commands from external devices, or outputs angular velocities ωx, ωy, ωz and accelerations Ax, Ay, Az detected by the MEMS sensor 30 and angular velocity ωz detected by the vibration element 40 to external devices. For example, SPI communication can be used as a communication method between the interface circuit section 66, the external device, the MEMS sensor 30, and the vibration element 40.

[0090] It should be noted that, as described above, in the sensor module 100, the vibration element 40 has a higher detection accuracy of angular velocity ωz than the Z-axis angular velocity sensor element 34z. Therefore, the interface circuit unit 66 can integrate the six signals—angular velocities ωx and ωy and accelerations Ax, Ay, and Az detected by the MEMS sensor 30 and the angular velocity ωz detected by the vibration element 40—and output them to the external device instead of outputting the angular velocity ωz detected by the Z-axis angular velocity sensor element 34z to the external device.

[0091] Alternatively, the interface circuit 66 can integrate the seven signals—angular velocities ωx, ωy, ωz and accelerations Ax, Ay, Az—detected by the MEMS sensor 30 and the angular velocity ωz detected by the vibration element 40, and output them to an external device. In this case, the user can choose to use the angular velocity ωz detected by the Z-axis angular velocity sensor element 34z, the angular velocity ωz detected by the vibration element 40, or both.

[0092] Furthermore, since the sensor module 100 has two sensors for detecting angular velocity around the Z-axis, namely the vibration element 40 and the Z-axis angular velocity sensor element 34z, even if one of the two sensors for detecting angular velocity around the Z-axis fails, the other sensor can still be used to detect the angular velocity around the Z-axis. Therefore, the robustness of angular velocity detection around the Z-axis can be improved.

[0093] 1.6. Effects

[0094] The sensor module 100 includes: a package 20 having a first space 102 and a second space 104 that overlap when viewed from a first direction; a vibration element 40 and an integrated circuit 60 disposed in the first space 102; and a MEMS sensor 30 disposed in the second space 104. The integrated circuit 60 is electrically connected to the vibration element 40 and the MEMS sensor 30, and when viewed from the first direction, the vibration element 40, the integrated circuit 60, and the MEMS sensor 30 overlap. Therefore, in the sensor module 100, for example, compared to a case where the vibration element, the integrated circuit, and the MEMS sensor do not overlap when viewed from the first direction, the dedicated area can be reduced. Thus, miniaturization can be achieved.

[0095] In the sensor module 100, the package 20 has a first recess 25 and a cover 28 that closes the first recess 25, and the first space 102 is formed by the first recess 25. Therefore, in the sensor module 100, the first space 102 can be airtightly sealed by the cover 28.

[0096] In the sensor module 100, when viewed from a first direction, the first recess 25 has a first portion 25a and a second portion 25b that overlap each other. The first portion 25a is located between the cover 28 and the second portion 25b, and its area is larger than that of the second portion 25b when viewed from the first direction. The vibration element 40 is disposed in the first portion 25a, and the integrated circuit 60 is disposed in the second portion 25b. Therefore, in the first space 102 of the sensor module 100, when viewed from the first direction, the vibration element 40 and the integrated circuit 60 can be arranged in an overlapping configuration.

[0097] In the sensor module 100, the package 20 has: a second recess 27 that opens on the opposite side of the first recess 25; a flat plate portion 23 that defines the bottom surfaces of the first recess 25 and the second recess 27; and a second space 104 formed by the second recess 27. Therefore, in the sensor module 100, when viewed from the first direction, the vibration element 40, the integrated circuit 60, and the MEMS sensor 30 can be arranged in an overlapping configuration.

[0098] In the sensor module 100, a substrate 10 with a closed second recess 27 is provided, and the MEMS sensor 30 is disposed on the substrate 10 in the second space 104. Therefore, in the sensor module 100, for example, compared with the case where the MEMS sensor 30 is disposed on the flat plate portion 23, the wiring design for the electrical connection between the MEMS sensor 30 and the integrated circuit 60 can be simplified.

[0099] In the sensor module 100, the substrate 10 is more flexible than the package 20. Therefore, when the sensor module 100 is mounted on a mounting substrate (not shown), the substrate 10 can mitigate the stress applied to the vibration element 40 and the MEMS sensor 30 caused by mounting to the mounting substrate. As a result, changes in the characteristics of the vibration element 40 and the MEMS sensor 30 caused by stress can be reduced.

[0100] In the sensor module 100, the substrate 10 has a second terminal 16 on the opposite side of the MEMS sensor 30. Therefore, in the sensor module 100, when the substrate 10 is mounted facing the mounting substrate, the mounting substrate can be connected to the second terminal 16.

[0101] 2. Vehicles

[0102] Next, the vehicle involved in this embodiment will be described with reference to the accompanying drawings. Figure 13 This is a schematic top view of the vehicle 200 involved in this embodiment.

[0103] like Figure 13 As shown, vehicle 200 is, for example, a car. It should be noted that vehicle 200 is not limited to cars; it can also be, for example, agricultural machinery such as tractors, construction machinery such as excavators.

[0104] Vehicle 200 includes, for example, a sensor module. Sensor module 100, within vehicle 200, maintains an attitude with its X-axis aligned with the longitudinal direction of vehicle 200, its Y-axis aligned with the lateral direction of vehicle 200, and its Z-axis aligned with the vertical direction of vehicle 200. Therefore, the X-axis of sensor module 100 is aligned with the roll axis of vehicle 200. The Y-axis of sensor module 100 is aligned with the pitch axis of vehicle 200. The Z-axis of sensor module 100 is aligned with the yaw axis of vehicle 200. Thus, the attitude of vehicle 200 is represented by the roll angle about the X-axis, the pitch angle about the Y-axis, and the yaw angle about the Z-axis.

[0105] It should be noted that the roll angle corresponds to the left-right tilt of vehicle 200. The pitch angle corresponds to the forward-backward tilt of vehicle 200. The yaw angle corresponds to the change in the direction of movement or orientation of vehicle 200.

[0106] Among the various controls for vehicle 200, the most important of the roll, pitch, and yaw angles is the yaw angle, which corresponds to the change in the direction of movement or azimuth of vehicle 200. This is because the detection error of the yaw angle (the difference between the actual value and the measured value) is directly related to the travel direction error of vehicle 200 (the difference between the actual travel direction and the measured travel direction), while the errors of the roll and pitch angles are not directly related to the travel direction error of vehicle 200. Therefore, to reduce the travel direction error of vehicle 200, it is effective to further improve the detection accuracy of the yaw angle. Although sensors capable of detecting all roll, pitch, and yaw angles with high precision could be used, this would lead to larger and more expensive sensors.

[0107] In sensor module 100, the vibration element 40 can detect the yaw angle with exceptionally high precision, and the MEMS sensor 30 can detect the roll and pitch angles with sufficient precision. Therefore, according to sensor module 100, while achieving miniaturization and cost reduction of the device, it can effectively contribute to reducing the travel direction error of vehicle 200. Thus, sensor module 100 has excellent compatibility and high affinity with vehicle 200.

[0108] The above-described embodiments and modifications are examples and are not intended to limit the scope. For example, the embodiments and modifications can be appropriately combined.

[0109] This invention includes configurations that are substantially the same as those described in the embodiments, for example, configurations with the same function, method, and result, or configurations with the same purpose and effect. Additionally, this invention includes configurations that replace non-essential parts of the configurations described in the embodiments. Furthermore, this invention includes configurations that have the same effect as those described in the embodiments or that can achieve the same purpose. Additionally, this invention includes configurations that incorporate commonly known general knowledge into the configurations described in the embodiments.

[0110] The following conclusions are drawn from the above implementation methods and variations.

[0111] One way the sensor module has:

[0112] The package has a first space and a second space that overlap when viewed from a first direction;

[0113] Vibration element and integrated circuit, disposed in the first space; and

[0114] MEMS sensors are configured in the second space.

[0115] The integrated circuit is electrically connected to the vibration element and the MEMS sensor.

[0116] When viewed from the first direction, the vibration element, the integrated circuit, and the MEMS sensor overlap.

[0117] This sensor module can reduce the required area.

[0118] Alternatively, in one embodiment of the sensor module,

[0119] The package has a first recess and a cover that closes the first recess.

[0120] The first space is formed by the first recess.

[0121] Based on this sensor module, the first space can be airtightly sealed through the cover.

[0122] Alternatively, in one embodiment of the sensor module,

[0123] When viewed from the first direction, the first recess has a first portion and a second portion that overlap each other.

[0124] The first part is located between the cover and the second part, and when viewed from the first direction, the area of ​​the first part is larger than that of the second part.

[0125] The vibrating element is disposed in the first part.

[0126] The integrated circuit is configured in the second part.

[0127] Based on this sensor module, when viewed from a first direction in a first space, the vibration element and integrated circuit can be arranged in an overlapping configuration.

[0128] Alternatively, in one embodiment of the sensor module,

[0129] The package has:

[0130] The second recess opens on the opposite side of the first recess;

[0131] The flat plate portion defines the bottom surfaces of the first recess and the second recess.

[0132] The second space is formed by the second recess.

[0133] Based on this sensor module, when viewed from the first direction, the vibration element, integrated circuit, and MEMS sensor can be arranged in an overlapping configuration.

[0134] Alternatively, in one embodiment of the sensor module,

[0135] A substrate having a closed second recess.

[0136] The MEMS sensor is disposed on the substrate in the second space.

[0137] This sensor module simplifies the wiring design for electrical connections between MEMS sensors and integrated circuits.

[0138] Alternatively, in one embodiment of the sensor module,

[0139] The substrate is more flexible than the package.

[0140] This sensor module can reduce the changes in the characteristics of vibration elements and MEMS sensors caused by stress.

[0141] Alternatively, in one embodiment of the sensor module,

[0142] The substrate has terminals on the opposite side of the MEMS sensor.

[0143] According to this sensor module, when the substrate is mounted facing the mounting substrate, the mounting substrate can be connected to the second terminal.

[0144] One approach to the vehicle includes one approach to the sensor module.

Claims

1. A sensor module, characterized in that, have: The package has a first space and a second space that overlap when viewed from a first direction; Vibration elements and integrated circuits are disposed in the first space; as well as MEMS sensors are configured in the second space. The integrated circuit is electrically connected to the vibration element and the MEMS sensor. When viewed from the first direction, the vibration element, the integrated circuit, and the MEMS sensor overlap.

2. The sensor module according to claim 1, characterized in that, The package has: the first recess; and The cover seals the first recess. The first space is formed by the first recess.

3. The sensor module according to claim 2, characterized in that, When viewed from the first direction, the first recess has a first portion and a second portion that overlap each other. The first part is located between the cover and the second part, and when viewed from the first direction, the area of ​​the first part is larger than that of the second part. The vibrating element is disposed in the first part. The integrated circuit is configured in the second part.

4. The sensor module according to claim 2, characterized in that, The package has: The second recess opens on the opposite side of the first recess; The flat plate portion defines the bottom surfaces of the first recess and the second recess. The second space is formed by the second recess.

5. The sensor module according to claim 4, characterized in that, The sensor module has a substrate that closes the second recess. The MEMS sensor is disposed on the substrate in the second space.

6. The sensor module according to claim 5, characterized in that, The substrate is made of a material that is more flexible than the package.

7. The sensor module according to claim 5, characterized in that, The substrate has terminals on the opposite side of the MEMS sensor.

8. A vehicle, characterized in that, Includes the sensor module according to any one of claims 1 to 7.

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