Physical quantity detection element, method for manufacturing the same, and physical quantity detection device

Abstract

A physical quantity detection element, a physical quantity detection device, and a method for manufacturing the physical quantity detection element are provided, which can effectively reduce the decrease in detection accuracy of physical quantities. The physical quantity detection element includes: a vibrating substrate, including a base, a plurality of vibrating arms connected to the base, and a protrusion protruding from the side of the base; and a first detection electrode, a second detection electrode, a third detection electrode, a fourth detection electrode, a driving electrode, and a driving constant potential electrode, disposed in any one of the plurality of vibrating arms. A wiring separation portion is disposed on the side of the protrusion, the wiring separation portion separating any one of the first detection electrode, the second detection electrode, the third detection electrode, and the fourth detection electrode from the driving constant potential electrode. When viewed from above the base, the driving electrode is disposed on the side of the protrusion opposite to the side of the wiring separation portion.

Description

Technical Field

[0001] This invention relates to physical quantity detection elements, physical quantity detection devices, and methods for manufacturing physical quantity detection elements. Background Technology

[0002] For example, the vibration element described in Patent Document 1 as an angular velocity sensor has a vibration substrate, wherein the vibration substrate includes a base, a first detection arm and a second detection arm extending from the base to one side and the other side in the Y-axis direction, a first connecting arm and a second connecting arm extending from the base to one side and the other side in the X-axis direction, a pair of first drive arms extending from the front end of the first connecting arm to one side and the other side in the Y-axis direction, a pair of second drive arms extending from the front end of the second connecting arm to one side and the other side in the Y-axis direction, a pair of support portions, and a beam portion connecting the base and each support portion.

[0003] Furthermore, the vibration element includes a first detection electrode disposed on two main surfaces of the first detection arm, a second detection electrode disposed on two side surfaces of the first detection arm, a third detection electrode disposed on two main surfaces of the second detection arm, a fourth detection electrode disposed on two side surfaces of the second detection arm, a drive input electrode disposed on two main surfaces of each first drive arm and two side surfaces of each second drive arm, and a drive output electrode disposed on two main surfaces of each first drive arm and two side surfaces of each second drive arm. Moreover, the first and fourth detection electrodes with the same polarity are both connected to a first charge amplifier, and the second and third detection electrodes with the same polarity are both connected to a second charge amplifier. With this configuration, the detection sensitivity of the angular velocity is improved because the amount of charge (current) input to the detection circuit is increased.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2015-184124 Summary of the Invention

[0005] However, in the vibration element of Patent Document 1, because any one of the first detection electrode, the second detection electrode, the third detection electrode and the fourth detection electrode is easily close to the drive input electrode, resulting in strong capacitive coupling between them, noise is easily superimposed on the detection signal, and thus the detection accuracy of angular velocity may decrease.

[0006] The physical quantity detection element of the present invention comprises: a vibrating substrate having a base, a plurality of vibrating arms connected to the base, and a protrusion extending from the side of the base; and

[0007] The first detection electrode, second detection electrode, third detection electrode, fourth detection electrode, driving electrode, and driving constant potential electrode are configured in any one of the plurality of vibrating arms. A wiring separation section is disposed on the side of the protrusion, which separates any one of the first detection electrode, the second detection electrode, the third detection electrode, and the fourth detection electrode from the driving constant potential electrode. When viewed from above, the driving electrode is positioned on the side of the protrusion opposite to the side of the wiring separation portion.

[0008] The physical quantity detection device of the present invention includes: the aforementioned physical quantity detection element; and

[0009] A circuit element having a driving circuit and a detection circuit, wherein the driving circuit drives the physical quantity detection element, and the detection circuit detects the physical quantity based on a detection signal from the physical quantity detection element.

[0010] The manufacturing method of the physical quantity detection element of the present invention includes: a substrate preparation step, wherein a vibrating substrate is prepared, wherein the vibrating substrate has a base, a plurality of vibrating arms connected to the base, and a protrusion protruding from the side of the base; The metal film formation process involves forming a metal film on the vibrating substrate; and In the electrode forming process, the metal film is patterned to form a first detection electrode, a second detection electrode, a third detection electrode, a fourth detection electrode, a driving electrode, and a driving constant potential electrode. In the electrode forming process, by removing the metal film located on the side of the protrusion, any one of the first detection electrode, the second detection electrode, the third detection electrode, and the fourth detection electrode is separated from the driving constant potential electrode. Attached Figure Description

[0011] Figure 1 This is a cross-sectional view of the physical quantity detection device according to the first embodiment.

[0012] Figure 2 This is a top view showing the interior of the package of the physical quantity detection device.

[0013] Figure 3 This is a top view showing the upper surface of the angular velocity sensor element.

[0014] Figure 4 This is a perspective view showing the lower surface of the angular velocity sensor element.

[0015] Figure 5 yes Figure 3 Sectional view along line AA in the diagram.

[0016] Figure 6 yes Figure 3 BB line section view.

[0017] Figure 7 This is a 3D view of the angular velocity sensor element.

[0018] Figure 8 This is a 3D view of the angular velocity sensor element.

[0019] Figure 9 This is a schematic diagram showing the driving state of the angular velocity sensor element.

[0020] Figure 10 This is a schematic diagram showing the driving state of the angular velocity sensor element.

[0021] Figure 11 This is a top view of the supporting substrate.

[0022] Figure 12 This is a cross-sectional view of the accelerometer sensor unit.

[0023] Figure 13 This is a top view of the first sensor unit.

[0024] Figure 14 This is a top view of the second sensor unit.

[0025] Figure 15 This is a block diagram of the detection circuit.

[0026] Figure 16 This is a flowchart illustrating the manufacturing process of an angular velocity sensor element.

[0027] Figure 17 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0028] Figure 18 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0029] Figure 19 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0030] Figure 20 This is a flowchart illustrating the manufacturing process of the angular velocity sensor element according to the second embodiment.

[0031] Figure 21 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0032] Explanation of reference numerals in the attached figures

[0033] 1: Physical quantity detection device; 2: Package; 21: Base; 211: Recess; 211a: First recess; 211b: Second recess; 211c: Third recess; 22: Cover; 23: Annular gasket; 3: Accelerometer sensor unit; 31: Support substrate; 311: First recess; 312: Second recess; 313: First anchor point; 314: Second anchor point; 32: First sensor part; 321: Movable part; 321a: Spring part; 321b: Movable plate; 321c: First movable comb electrode; 321d: Second movable comb electrode; 322: First fixed body; 322a: First fixed comb electrode; 323: Second fixed body; 323a: Second fixed comb electrode; 33: Second sensor part 331: Movable part; 331a: Spring part; 331b: Movable plate; 331c: First movable comb tooth electrode; 331d: Second movable comb tooth electrode; 331e: Third movable comb tooth electrode; 331f: Fourth movable comb tooth electrode; 332: First fixed body; 332a: First fixed comb tooth electrode; 333: Second fixed body; 333a: Second fixed comb tooth electrode; 334: Third fixed body; 334a: Third fixed comb tooth electrode; 335: Fourth fixed body; 335a: Fourth fixed comb tooth electrode; 34: Cover; 341: Recess; 5: Angular velocity sensor element; 50: Base; 500: Vibration substrate; 51: First detection arm; 52: Second detection arm; 53: First connecting arm; 54: Second Connecting arm; 55: First drive arm; 56: First drive arm; 57: Second drive arm; 58: Second drive arm; 59: Protrusion; 591: First protrusion; 592: Second protrusion; 593: Third protrusion; 594: Fourth protrusion; 6: Support substrate; 61: Substrate; 611: Opening; 62: Lead wire; 7: Circuit element; 71: First control circuit section; 72: Second control circuit section; 73: Interface circuit section; 75: Detection circuit; 751: Charge amplifier; 752: Charge amplifier; 753: Differential amplifier circuit; 754: AC amplifier circuit; 755: Synchronous detector circuit; 756: Smoothing circuit; 757: Variable amplifier circuit; 758: Filter circuit; 79: Drive circuit; A x: Acceleration; Ay: Acceleration; Az: Acceleration; B1: Bonding component; B2: Bonding component; E: Metal film; E1: Driving electrode; E2: Driving constant potential electrode; E3: First detection electrode; E4: Second detection electrode; E5: Third detection electrode; E6: Fourth detection electrode; E7: Constant potential electrode; E71: First constant potential electrode; E72: Second constant potential electrode; G: Wiring separation section; G1: First wiring separation section; G2: Second wiring separation section; H: Stack; J: Swing axis; M: Mask; O: Center; S: Storage space; S1: Substrate preparation process; S2: Metal film formation process; S3: Electrode formation process; S4: Protrusion removal process; T1: Terminal for driving electrode;T2: Terminal for driving the constant potential electrode; T3: Terminal for the first detection electrode; T4: Terminal for the second detection electrode; T5: Terminal for the third detection electrode; T6: Terminal for the fourth detection electrode; T91: Terminal; T92: Terminal; T93: External terminal; T94: Terminal; W1: Wire; W2: Wire; ωz: Angular velocity. Detailed Implementation

[0034] The physical quantity detection element, physical quantity detection device, and manufacturing method of the physical quantity detection element according to the present invention will be described in detail below based on the embodiments shown in the accompanying drawings. It should be noted that, for ease of explanation, except... Figure 15 , Figure 16 and Figure 20 In the figures other than those shown, three mutually orthogonal axes are depicted as the X-axis, Y-axis, and Z-axis. Furthermore, for ease of explanation, in the following text, the direction along the X-axis, which is the second direction, will also be referred to as the "X-axis direction," the direction along the Y-axis, which is the first direction, will also be referred to as the "Y-axis direction," and the direction along the Z-axis will also be referred to as the "Z-axis direction." Additionally, the side with the arrow on each axis will be referred to as the "positive side," and the opposite side will be referred to as the "negative side." Furthermore, the positive side of the Z-axis direction will be referred to as "up," and the negative side of the Z-axis direction will be referred to as "down."

[0035] First Implementation Method

[0036] Figure 1 This is a cross-sectional view of the physical quantity detection device according to the first embodiment. Figure 2 This is a top view showing the interior of the package of the physical quantity detection device. Figure 3 This is a top view showing the upper surface of the angular velocity sensor element. Figure 4 This is a perspective view showing the lower surface of the angular velocity sensor element. Figure 5 yes Figure 3 Sectional view along line AA in the diagram. Figure 6 yes Figure 3 BB line section view. Figure 7 This is a 3D view of the angular velocity sensor element. Figure 8 This is a 3D view of the angular velocity sensor element. Figure 9 This is a schematic diagram showing the driving state of the angular velocity sensor element. Figure 10 This is a schematic diagram showing the driving state of the angular velocity sensor element. Figure 11 This is a top view of the supporting substrate. Figure 12 This is a cross-sectional view of the accelerometer sensor unit. Figure 13 This is a top view of the first sensor unit. Figure 14 This is a top view of the second sensor unit. Figure 15 This is a block diagram of the detection circuit. Figure 16 This is a flowchart illustrating the manufacturing process of an angular velocity sensor element. Figure 17 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element. Figure 18 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element. Figure 19 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0037] Figure 1 The physical quantity detection device 1 shown is a composite sensor for detecting acceleration and angular velocity. It has a package 2, an acceleration sensor unit 3 housed in the package 2, an angular velocity sensor element 5 as the physical quantity detection element, a support substrate 6, and a circuit element 7. These parts will be described in turn below.

[0038] Package 2

[0039] like Figure 1 and Figure 2 As shown, the package 2 has a cavity-shaped base 21 and a plate-shaped cover 22. The base 21 has a recess 211 opening onto its upper surface. The cover 22 is engaged with the upper surface of the base 21 by an annular gasket 23, which blocks the opening of the recess 211. By blocking the recess 211 with the cover 22, an airtight storage space S is formed within the package 2, housing the aforementioned components. This effectively protects the accelerometer unit 3, the angular velocity sensor element 5, and the circuit element 7. It should be noted that the storage space S is airtightly sealed, presenting a depressurized state, preferably closer to a vacuum. This reduces viscous resistance, improving the vibration characteristics of the angular velocity sensor element 5, which is disposed in an exposed state within the storage space S. However, the atmosphere of the storage space S is not particularly limited.

[0040] The material used to construct the base 21 is not particularly limited; for example, various ceramics such as alumina can be used. Similarly, the material used to construct the cover 22 is not particularly limited, as long as it is a component with a coefficient of linear expansion similar to that of the base 21. For example, if the base 21 is made of ceramic, an alloy such as Kova alloy is preferred.

[0041] Furthermore, the recess 211 has a first recess 211a opening onto the upper surface of the base 21, a second recess 211b opening onto the bottom surface of the first recess 211a and having an opening area smaller than that of the first recess 211a, and a third recess 211c opening onto the bottom surface of the second recess 211b and having an opening area smaller than that of the second recess 211b. The angular velocity sensor element 5 is disposed on the bottom surface of the first recess 211a, separated from the support substrate 6, and the circuit element 7 and the acceleration sensor unit 3 are stacked along the Z-axis direction on the bottom surface of the third recess 211c. It should be noted that, hereinafter, the stack of the circuit element 7 and the acceleration sensor unit 3 is also referred to as "stack H".

[0042] Furthermore, a plurality of terminals T91 are disposed on the bottom surface of the second recess 211b. Each terminal T91 is electrically connected to the circuit element 7 via a conductive wire W1. Additionally, a plurality of terminals T92 are disposed on the bottom surface of the first recess 211a. Each terminal T92 is electrically connected to the angular velocity sensor element 5 via a conductive bonding member B1 and a support substrate 6. Furthermore, each terminal T92 is electrically connected to its corresponding terminal T91 via internal wiring (not shown) formed within the base 21. Additionally, a plurality of external terminals T93 are disposed on the lower surface of the base 21. Each external terminal T93 is electrically connected to its corresponding terminal T91 via internal wiring (not shown) formed within the base 21.

[0043] Angular velocity sensor element 5

[0044] like Figure 1 As shown, the angular velocity sensor element 5 is disposed on the upper side of the laminate H, and overlaps with the laminate H when viewed from above along the Z-axis. By arranging the angular velocity sensor element 5 and the laminate H in this overlapping configuration along the Z-axis, the planar width of the physical quantity detection device 1 can be suppressed, enabling miniaturization of the physical quantity detection device 1. Furthermore, since the angular velocity sensor element 5 can be disposed in a large space located on the upper side of the laminate H, it is easy to enlarge the angular velocity sensor element 5, and correspondingly, the detection accuracy of the angular velocity sensor element 5 is improved.

[0045] Angular velocity sensor element 5 is a crystal resonant element capable of detecting the angular velocity ωz about the Z-axis. Such an angular velocity sensor element 5 is as follows: Figure 3 and Figure 4 As shown, the angular velocity sensor element 5 has a base 50 and a plurality of vibrating arms connected to the base 50. The plurality of vibrating arms includes a first detection arm 51, a second detection arm 52, a first connecting arm 53, a second connecting arm 54, first drive arms 55 and 56, and second drive arms 57 and 58. Specifically, the angular velocity sensor element 5 has a vibration substrate 500, which is a crystal substrate, integrally formed from the base 50 located at the center of the element, the first detection arm 51 and the second detection arm 52 extending from the base 50 to one side and the other side in the Y-axis direction, the first connecting arm 53 and the second connecting arm 54 extending from one side and the other side in the X-axis direction, a pair of first drive arms 55 and 56 extending from the front end of the first connecting arm 53 to one side and the other side in the Y-axis direction, and a pair of second drive arms 57 and 58 extending from the front end of the second connecting arm 54 to one side and the other side in the Y-axis direction. With this configuration, the angular velocity sensor element 5 has excellent vibration balance, thereby enabling high-precision detection of the angular velocity ωz.

[0046] In addition, such as Figure 5 and Figure 6As shown, recesses opening onto the two main surfaces, namely the upper and lower surfaces, are formed in the first detection arm 51, the second detection arm 52, the first drive arms 55 and 56, and the second drive arms 57 and 58, respectively. This angular velocity sensor element 5, as described later, is supported in the base 50 by a support substrate 6.

[0047] In addition, such as Figure 3 and Figure 4 As shown, the vibrating substrate 500 has a protrusion 59 protruding from the base 50. Furthermore, the protrusion 59 has a first protrusion 591 and a second protrusion 592 protruding from the side of the base 50 facing the positive X-axis direction, and a third protrusion 593 and a fourth protrusion 594 protruding from the side of the base 50 facing the negative X-axis direction. That is, the first protrusion 591 and the second protrusion 592 are located on opposite sides of the base 50 relative to the base 50, as are the third protrusion 593 and the fourth protrusion 594. Additionally, the second protrusion 592 and the fourth protrusion 594 are located on the positive Y-axis direction (towards the first detection arm 51) relative to the center O of the base 50, while the first protrusion 591 and the third protrusion 593 are located on the negative Y-axis direction (towards the second detection arm 52) relative to the center O of the base 50. With this configuration, the protrusion 59 can be positioned in a well-balanced manner around the base 50, thus effectively suppressing the center of gravity from deviating from the center O. Therefore, it is possible to suppress the decrease in vibration balance of the angular velocity sensor element 5.

[0048] In addition, such as Figure 3 and Figure 4 As shown, the angular velocity sensor element 5 has a driving electrode E1 disposed on both sides of the first driving arms 55 and 56 and the two main surfaces of the second driving arms 57 and 58, a driving constant potential electrode E2 disposed on both main surfaces of the first driving arms 55 and 56 and the two main surfaces of the second driving arms 57 and 58, a first detection electrode E3 disposed on the two main surfaces of the first detection arm 51, a second detection electrode E4 disposed on both sides of the first detection arm 51, a third detection electrode E5 disposed on the two main surfaces of the second detection arm 52, and a fourth detection electrode E6 disposed on both sides of the second detection arm 52.

[0049] In addition, such as Figure 4As shown, the angular velocity sensor element 5 has six terminals disposed on the lower surface of the base 50 (the main surface on one side of the support substrate 6). These six terminals include a drive electrode terminal T1 electrically connected to the drive electrode E1, a drive constant potential electrode terminal T2 electrically connected to the drive constant potential electrode E2, a first detection electrode terminal T3 electrically connected to the first detection electrode E3, a second detection electrode terminal T4 electrically connected to the second detection electrode E4, a third detection electrode terminal T5 electrically connected to the third detection electrode E5, and a fourth detection electrode terminal T6 electrically connected to the fourth detection electrode E6.

[0050] In addition, such as Figure 3 and Figure 4 As shown, the angular velocity sensor element 5 has a constant potential electrode E7 disposed on the lower surface of the base 50. The constant potential electrode E7 is connected to a constant potential, particularly ground (GND), during operation of the physical quantity detection device 1. This constant potential electrode E7 is divided into a first constant potential electrode E71 and a second constant potential electrode E72 by the driving constant potential electrode E2. Furthermore, the first constant potential electrode E71 is widely distributed in the region on the positive side of the Y-axis direction of the center O, and is disposed between the first and second detection electrodes E3, E4 and the terminals T3, T4 for the first and second detection electrodes and the driving electrode terminal T1. Conversely, the second constant potential electrode E72 is widely distributed in the region on the negative side of the Y-axis direction of the center O, and is disposed between the third and fourth detection electrodes E5, E6 and the terminals T5, T6 for the third and fourth detection electrodes and the driving electrode terminal T1. With this configuration, the constant potential electrode E7 can effectively suppress capacitive coupling between the driving electrode terminal T1 and the first to fourth detection electrodes E3 to E6 (the first to fourth detection electrode terminals T3 to T6). Therefore, the driving signal applied to the driving electrode E1 is less likely to be mixed with the detection signals taken from the first to fourth detection electrodes E3 to E6, resulting in a detection signal with less noise. Thus, angular velocity ωz can be detected with higher precision.

[0051] It should be noted that, as described below, these electrodes E1 to E7 and terminals T1 to T6 are formed by patterning the metal film E deposited on the vibrating substrate 500 using photolithography and etching techniques. In other words, the portions where electrodes E1 to E7 and terminals T1 to T6 are not formed are the portions obtained after removing the metal film E from the vibrating substrate 500.

[0052] Furthermore, a wiring separation section G is provided on the side of the protrusion 59 to separate any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 from the driving constant potential electrode E2. Also, when the base 50 is viewed from above (from the Z-axis direction), the driving electrode E1 on the second connecting arm 54 is positioned on the side of the protrusion 59 opposite to the side of the wiring separation section G. With this configuration, any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 is difficult to approach the driving electrode E1, effectively reducing their capacitive coupling. Therefore, the driving signal applied to the driving electrode E1 is less likely to be mixed into the detection signals taken from the first to fourth detection electrodes E3 to E6, resulting in a detection signal with less noise. Therefore, angular velocity ωz can be detected with higher accuracy.

[0053] Specifically, such as Figure 3 and Figure 4 As shown, the wiring separation section G has a first wiring separation section G1 disposed on the side of the first protrusion 591 and a second wiring separation section G2 disposed on the side of the second protrusion 592. Furthermore, the first wiring separation section G1 is disposed on the side of the first protrusion 591 facing the negative side in the Y-axis direction (the side of the second detection arm 52), that is, facing the side opposite to the second protrusion 592. The second wiring separation section G2 is disposed on the side of the second protrusion 592 facing the positive side in the Y-axis direction (the side of the first detection arm 51), that is, facing the side opposite to the first protrusion 591. Moreover, through the first wiring separation section G1, the fourth detection electrode E6 and the driving constant potential electrode E2 are separated on the side of the vibrating substrate 500, and through the second wiring separation section G2, the second detection electrode E4 and the driving constant potential electrode E2 are separated on the side of the vibrating substrate 500.

[0054] In addition, such as Figure 3 and Figure 4As shown, when viewing the base 50 from above (from the Z-axis direction), the drive electrode E1 on the second connecting arm 54 is positioned on the side of the first protrusion 591 opposite to the side of the first wiring separation portion G1. That is, the first wiring separation portion G1 is located on one side of the first protrusion 591 (negative side in the Y-axis direction), while the drive electrode E1 on the second connecting arm 54 is located on the other side of the first protrusion 591 (positive side in the Y-axis direction). With this configuration, the proximity of the drive electrode E1 to the fourth detection electrode E6 can be effectively suppressed, and their capacitive coupling can be effectively reduced. Similarly, when viewing the base 50 from above (from the Z-axis direction), the drive electrode E1 on the second connecting arm 54 is positioned on the side of the second protrusion 592 opposite to the side of the second wiring separation portion G2. That is, the second wiring separation portion G2 is located on one side of the second protrusion 592 (positive side in the Y-axis direction), while the drive electrode E1 on the second connecting arm 54 is located on the other side of the second protrusion 592 (negative side in the Y-axis direction). With this configuration, the proximity of the driving electrode E1 to the second detection electrode E4 can be effectively suppressed, and their capacitive coupling can be effectively reduced. Therefore, the angular velocity detection accuracy of the angular velocity sensor element 5 is improved.

[0055] Here, according to Figure 7 and Figure 8 As can be seen, in the angular velocity sensor element 5, the metal film is not removed from the vibrating substrate 500 on the side facing the positive X-axis and the side facing the negative X-axis. On the other hand, a portion of the metal film is removed from the vibrating substrate 500 on the side facing the positive Y-axis and the side facing the negative Y-axis. With this configuration, as will be described later, the number of exposures in the photolithography technique can be reduced, and correspondingly, the manufacturing of the angular velocity sensor element 5 becomes simpler.

[0056] The configuration of the angular velocity sensor element 5 has been described above. Next, the method for detecting the angular velocity ωz using the angular velocity sensor element 5 will be explained. When a drive signal is applied to the drive electrode E1, as... Figure 9 As shown, the first drive arms 55 and 56 and the second drive arms 57 and 58 bend and vibrate in opposite phases along the X-axis. This state is hereinafter referred to as the "drive vibration mode". In this state, the vibrations of the first drive arms 55 and 56 and the second drive arms 57 and 58 are canceled, and the first and second detection arms 51 and 52 do not vibrate. When an angular velocity ωz is applied to the angular velocity sensor element 5 while driving in the drive vibration mode, as shown... Figure 10 As shown, the Coriolis force acts on the first and second drive arms 55, 56, 57, and 58, exciting bending vibrations in the Y-axis direction. The first and second detection arms 51 and 52 then perform bending vibrations in the opposite phase along the X-axis direction in response to these bending vibrations. This state will be referred to as the "detection vibration mode" below.

[0057] The charge generated in the first detection arm 51 by this detection vibration mode is taken out as a detection signal from the first and second detection electrodes E3 and E4, and the charge generated in the second detection arm 52 by this detection vibration mode is taken out as a detection signal from the third and fourth detection electrodes E5 and E6. The angular velocity ωz is calculated based on these detection signals. In particular, according to the vibration substrate 500 with the shape of this embodiment, the vibration balance of the driving vibration mode is high, and the angular velocity ωz can be detected with higher accuracy. It should be noted that the processing method of the detection signals taken out from the first to fourth detection electrodes E3 to E6 will be described in the description of the circuit element 7 described later. In addition, in the following text, the detection signal taken out from the first detection electrode E3 is also referred to as the "first detection signal", the detection signal taken out from the second detection electrode E4 is also referred to as the "second detection signal", the detection signal taken out from the third detection electrode E5 is also referred to as the "third detection signal", and the detection signal taken out from the fourth detection electrode E6 is also referred to as the "fourth detection signal".

[0058] The angular velocity sensor element 5 has been described above. There are no particular limitations on the configuration of the angular velocity sensor element 5. For example, in this embodiment, the first wiring separation section G1 separates the fourth detection electrode E6 from the driving constant potential electrode E2, but it is not limited to this; it can also separate any one of the first, second, and third detection electrodes E3, E4, and E5 from the driving constant potential electrode E2. Similarly, the second wiring separation section G2 separates the second detection electrode E4 from the driving constant potential electrode E2, but it is not limited to this; it can also separate any one of the first, third, and fourth detection electrodes E3, E5, and E6 from the driving constant potential electrode E2. Furthermore, in this embodiment, the protrusion 59 has first, second, third, and fourth protrusions 591, 592, 593, and 594; however, as long as at least the first protrusion 591 is present, at least one of the second, third, and fourth protrusions 592, 593, and 594 can be omitted. Additionally, other protrusions may also be provided.

[0059] Support base plate 6

[0060] like Figure 1 As shown, the support base plate 6 supports the angular velocity sensor element 5 and also functions to electrically connect the angular velocity sensor element 5 to the terminal T92 on the base 21. In this way, since the support base plate 6 is located between the base 21 and the angular velocity sensor element 5, thermal stress and impact are less likely to be applied to the angular velocity sensor element 5, thereby improving the detection accuracy of the angular velocity ωz by the angular velocity sensor element 5.

[0061] The support substrate 6 is a substrate for TAB (Tape Automated Bonding) mounting, used to support the angular velocity sensor element 5 by lifting it from below. For example... Figure 11 As shown, the support substrate 6 has a substrate 61 and eight leads 62 disposed on the substrate 61. Furthermore, when viewed from above in the Z-axis direction, the substrate 61 is frame-shaped and has an opening 611 in the center. The substrate 61 is made of a thin film of an insulating resin such as polyimide. However, the material of the substrate 61 is not particularly limited; for example, it can be made of an insulating resin other than polyimide. Such a substrate 61 is fixed to the bottom surface of the first recess 211a at both ends in the X-axis direction by a plurality of (eight) bonding members B1. Each lead 62 is electrically connected to a terminal T92 formed on the bottom surface of the first recess 211a via the bonding members B1.

[0062] The eight leads 62 are bonding leads supporting the angular velocity sensor element 5 and are conductive wiring patterns. In this embodiment, each lead 62 is made of a metal foil such as copper foil. This facilitates the formation of the leads 62. The base ends of each lead 62 are supported on the lower surface of the substrate 61. In addition, each lead 62 bends towards the Z-axis midway along its extension direction to tilt upwards, and its front end passes through the opening 611 and is located higher than the substrate 61 (see reference). Figure 1 Furthermore, the base 50 of the angular velocity sensor element 5 is joined to the front end of each lead 62 via a conductive bonding member B2. These eight leads 62 are electrically connected to the drive electrode terminal T1, the drive constant potential electrode terminal T2, the first detection electrode terminal T3, the second detection electrode terminal T4, the third detection electrode terminal T5, the fourth detection electrode terminal T6, the first constant potential electrode E71, and the second constant potential electrode E72. It should be noted that the bonding member B2 in this embodiment is a gold bump. However, the bonding member B2 is not limited to this; for example, it may be silver paste, solder, conductive adhesive material, etc.

[0063] The support substrate 6 has been described above. There are no particular limitations on the composition of the support substrate 6.

[0064] Accelerometer sensor unit 3

[0065] Accelerometer unit 3 is a triaxial accelerometer unit capable of independently detecting acceleration Ax in the X-axis direction, acceleration Ay in the Y-axis direction, and acceleration Az in the Z-axis direction. With this configuration, the physical quantity detection device 1 can have more detection axes, increasing its convenience. Furthermore, accelerometer unit 3 is a silicon MEMS (Micro-Electro-Mechanical Systems). This configuration allows for miniaturization of accelerometer unit 3.

[0066] like Figure 12 As shown, the accelerometer sensor unit 3 includes a support substrate 31, a first sensor portion 32 and a second sensor portion 33 supported on the support substrate 31, and a cover 34 bonded to the support substrate 31 and housing the first and second sensor portions 32 and 33 between the cover 34 and the support substrate 31. The support substrate 31 and the first and second sensor portions 32 and 33 are integrally formed, for example, from an SOI (silicon on insulator) substrate. Specifically, the support substrate 31 is formed from the entire SOI substrate, and the first and second sensor portions 32 and 33 are formed from the upper silicon layer (device layer). The cover 34 is formed from a silicon substrate, and its lower surface is bonded to the upper surface of the support substrate 31 via a bonding member (not shown). With this configuration, the accelerometer sensor unit 3 can be easily and precisely manufactured using a silicon semiconductor process.

[0067] The support substrate 31 has a first recess 311 and a second recess 312 opening on its upper surface. These first and second recesses 311 and 312 are arranged along the X-axis. When viewed from the Z-axis, the first recess 311 overlaps with the first sensor portion 32 and functions as a retraction portion to avoid contact with the first sensor portion 32. On the other hand, when viewed from the Z-axis, the second recess 312 overlaps with the second sensor portion 33 and functions as a retraction portion to avoid contact with the second sensor portion 33. In addition, the support substrate 31 has a columnar first anchor point 313 erected at the center of the bottom surface of the first recess 311 and a columnar second anchor point 314 erected at the center of the bottom surface of the second recess 312. Furthermore, the first sensor portion 32 is fixed to the upper surface of the first anchor point 313, and the second sensor portion 33 is fixed to the upper surface of the second anchor point 314.

[0068] The first sensor unit 32 is a sensor unit that detects acceleration Az in the Z-axis direction. Such a first sensor unit 32 is as follows: Figure 13As shown, it has a movable part 321, a first fixed body 322, and a second fixed body 323. Furthermore, the movable part 321, the first fixed body 322, and the second fixed body 323 are respectively fixed to the upper surface of the first anchor point 313. It should be noted that... Figure 13 In the diagram, shading is used to make the parts easier to understand, but this does not represent a cross-section.

[0069] Furthermore, the first fixing body 322 has a first fixed comb electrode 322a located on the positive side of the X-axis direction relative to the first anchor point 313. On the other hand, the second fixing body 323 has a second fixed comb electrode 323a located on the negative side of the X-axis direction relative to the first anchor point 313.

[0070] Furthermore, the movable part 321 includes a spring portion 321a extending from the first anchor point 313 to both sides in the Y-axis direction, and a movable plate 321b supported by the first anchor point 313 via the spring portion 321a and oscillating relative to the support base plate 31 about the swing axis J along the Y-axis by the elastic deformation of the spring portion 321a. Additionally, the movable plate 321b has a first movable comb electrode 321c engaging with the first fixed comb electrode 322a and a second movable comb electrode 321d engaging with the second fixed comb electrode 323a. Furthermore, the movable plate 321b is asymmetrical with respect to the swing axis J; the mass of its portion on the negative side in the X-axis direction is greater than the mass of its portion on the positive side in the X-axis direction relative to the swing axis J.

[0071] In the first sensor unit 32 configured in this way, a first electrostatic capacitance is formed between the first fixed comb tooth electrode 322a and the first movable comb tooth electrode 321c, and a second electrostatic capacitance is formed between the second fixed comb tooth electrode 323a and the second movable comb tooth electrode 321d. When an acceleration Az is applied in the Z-axis direction, the movable plate 321b elastically deforms the spring part 321a according to the magnitude and orientation of the applied acceleration Az, and also oscillates around the swing axis J. The first and second electrostatic capacitances change together with this oscillation. Therefore, the applied acceleration Az can be detected based on the changes in the first and second electrostatic capacitances.

[0072] The second sensor unit 33 is a sensor unit that independently detects the acceleration Ax in the X-axis direction and the acceleration Ay in the Y-axis direction, respectively. Such a second sensor unit 33 is as follows: Figure 14 As shown, it includes a movable part 331, a first fixed body 332, a second fixed body 333, a third fixed body 334, and a fourth fixed body 335. Furthermore, these movable parts 331, first fixed bodies 332, second fixed bodies 333, third fixed bodies 334, and fourth fixed bodies 335 are respectively fixed to the upper surface of the second anchor point 314. It should be noted that... Figure 14In the diagram, shadows are used to make the parts easier to understand, but this does not represent a cross-section.

[0073] Furthermore, the first fixing body 332 has a first fixed comb electrode 332a located on the positive side of the X-axis direction relative to the second anchor point 314. Additionally, the second fixing body 333 has a second fixed comb electrode 333a located on the negative side of the X-axis direction relative to the second anchor point 314. The first and second fixing bodies 332 and 333 are symmetrically arranged with respect to the second anchor point 314.

[0074] Furthermore, the third fixing body 334 has a third fixed comb electrode 334a located on the positive side of the Y-axis direction relative to the second anchor point 314. Additionally, the fourth fixing body 335 has a fourth fixed comb electrode 335a located on the negative side of the Y-axis direction relative to the second anchor point 314. The third and fourth fixing bodies 334 and 335 are symmetrically arranged with respect to the second anchor point 314.

[0075] Additionally, the movable part 331 has four spring portions 331a extending radially from the second anchor point 314, and a frame-shaped movable plate 331b supported by the second anchor point 314 via the spring portions 331a and displaced relative to the support base plate 31 in the X-axis and Y-axis directions by the elastic deformation of the spring portions 331a. Furthermore, the movable plate 331b has a first movable comb electrode 331c engaging with the first fixed comb electrode 332a, a second movable comb electrode 331d engaging with the second fixed comb electrode 333a, a third movable comb electrode 331e engaging with the third fixed comb electrode 334a, and a fourth movable comb electrode 331f engaging with the fourth fixed comb electrode 335a.

[0076] In the second sensor unit 33 configured in this way, a first electrostatic capacitance is formed between the first fixed comb electrode 332a and the first movable comb electrode 331c, a second electrostatic capacitance is formed between the second fixed comb electrode 333a and the second movable comb electrode 331d, a third electrostatic capacitance is formed between the third fixed comb electrode 334a and the third movable comb electrode 331e, and a fourth electrostatic capacitance is formed between the fourth fixed comb electrode 335a and the fourth movable comb electrode 331f. When an acceleration Ax is applied in the X-axis direction, the movable plate 331b will elastically deform the spring part 331a according to the magnitude and direction of the applied acceleration Ax, and displace along the X-axis direction. The first and second electrostatic capacitances change in conjunction with this displacement. It should be noted that the third and fourth electrostatic capacitances do not actually change at this time. Therefore, the applied acceleration Ax can be detected based on the change in the first and second electrostatic capacitances. On the other hand, when an acceleration Ay is applied in the Y-axis direction, the movable plate 331b will elastically deform the spring part 331a according to the magnitude and direction of the applied acceleration Ay, and simultaneously displace along the Y-axis direction. The third and fourth electrostatic capacitances change in conjunction with this displacement. It should be noted that, at this time, the first and second electrostatic capacitances do not actually change. Therefore, the applied acceleration Ay can be detected based on the changes in the third and fourth electrostatic capacitances.

[0077] like Figure 12 As shown, the cover 34 has a recess 341 that opens onto its lower surface. It is also joined to the upper surface of the support substrate 31 in such a way that the first and second sensor portions 32 and 33 are housed within the recess 341.

[0078] Here, as Figure 2 As shown, the support substrate 31 is larger than the cover 34, and a portion of its upper surface extends out from the cover 34. Furthermore, a plurality of terminals T94, electrically connected to the first and second sensor sections 32 and 33, are disposed in this extended portion. Each terminal T94 is electrically connected to the circuit element 7 via a conductive wire W2.

[0079] The acceleration sensor unit 3 has been described above. However, there are no particular limitations on the configuration of the acceleration sensor unit 3. For example, the second sensor unit 33 may be configured to detect only one of accelerations Ax and Ay. Alternatively, the first and second sensor units 32 and 33 may both detect the same acceleration, such as Az. Furthermore, for example, it may be possible to have a sensor unit that detects acceleration Ax, a sensor unit that detects acceleration Ay, and a sensor unit that detects acceleration Az, totaling three sensor units. Alternatively, the acceleration sensor unit 3 may be omitted.

[0080] Circuit element 7

[0081] like Figure 1 As shown, circuit element 7 is joined and fixed to the bottom surface of the third recess 211c via a joining member (not shown). Furthermore, the acceleration sensor unit 3 is stacked on the upper surface of circuit element 7 to form a laminate H. Additionally, as... Figure 2 As shown, circuit element 7 is electrically connected to terminal T91 disposed on the bottom surface of the second recess 211b via a conductive wire W1. However, it is not limited to this. Conversely, in this embodiment, the acceleration sensor unit 3 can be bonded to the bottom surface of the third recess 211c, and a laminate H can be formed by stacking circuit element 7 on the upper surface of the acceleration sensor unit 3.

[0082] Additionally, circuit element 7 is electrically connected to the acceleration sensor unit 3 and the angular velocity sensor element 5 via the base 21, and is input with signals from the acceleration sensor unit 3 and the angular velocity sensor element 5. Circuit element 7 is, for example, a Micro Controller Unit (MCU), which comprehensively controls the various parts of the physical quantity detection device 1. Such a circuit element 7 is... Figure 1 As shown, it includes: a first control circuit 71 that controls the driving of the acceleration sensor unit 3 and detects accelerations Ax, Ay, and Az based on signals input from the acceleration sensor unit 3; a second control circuit 72 that controls the driving of the angular velocity sensor element 5 and detects angular velocity ωz based on signals input from the angular velocity sensor element 5; and an interface circuit 73 that performs communication with external devices.

[0083] In addition, such as Figure 15 As shown, the second control circuit section 72 includes a drive circuit 79 for applying a drive signal to the angular velocity sensor element 5 to drive the angular velocity sensor element 5, and a detection circuit 75 for detecting the angular velocity ωz based on the detection signal from the angular velocity sensor element 5. Furthermore, the detection circuit 75 includes a charge amplifier 751, a charge amplifier 752, a differential amplifier circuit 753, an AC amplifier circuit 754, a synchronous detector circuit 755, a smoothing circuit 756, a variable amplifier circuit 757, and a filter circuit 758.

[0084] The charge amplifier 751 is configured to include an operational amplifier, a feedback resistor, and a feedback capacitor. A first detection signal output from the first detection electrode E3 and a fourth detection signal output from the fourth detection electrode E6 are input to the inverting input terminal (- terminal) of the operational amplifier, while the non-inverting input terminal (+ terminal) of the operational amplifier is fixed at a reference potential. It should be noted that the first and fourth detection signals are signals with the same polarity. The charge amplifier 751 converts the first and fourth detection signals input to the operational amplifier into AC voltage signals.

[0085] The charge amplifier 752 is configured to include an operational amplifier, a feedback resistor, and a feedback capacitor. A second detection signal output from the second detection electrode E4 and a third detection signal output from the third detection electrode E5 are input to the inverting input terminal (- terminal) of the operational amplifier, while the non-inverting input terminal (+ terminal) of the operational amplifier is fixed at a reference potential. It should be noted that the second and third detection signals are signals with the same polarity. Furthermore, the polarity of the second and third detection signals is opposite to that of the first and fourth detection signals. The charge amplifier 752 converts the second and third detection signals input to the operational amplifier into AC voltage signals.

[0086] The output signals of charge amplifiers 751 and 752 are input to differential amplifier circuit 753. Differential amplifier circuit 753 outputs a signal obtained by amplifying the potential difference between the output signals of charge amplifiers 751 and 752. The output signal of differential amplifier circuit 753, after being amplified by AC amplifier circuit 754, is input to synchronous detector circuit 755. Synchronous detector circuit 755 extracts the angular velocity component, for example, by synchronously detecting the output signal of AC amplifier circuit 754 based on a drive signal generated by drive circuit 79. The angular velocity component signal extracted by synchronous detector circuit 755 is smoothed into a DC voltage signal by smoothing circuit 756 and input to variable amplifier circuit 757. Variable amplifier circuit 757 amplifies or attenuates the output signal of smoothing circuit 756 according to a set ratio to change the angular velocity sensitivity. The signal amplified or attenuated by variable amplifier circuit 757 is input to filter circuit 758. The filter circuit 758 removes high-frequency noise components outside the sensor's frequency band from the output signal of the variable amplifier circuit 757, and outputs a detection signal whose polarity and voltage level correspond to the direction and magnitude of the angular velocity ωz. This detection signal is then output to the outside of the device from the interface circuit section 73.

[0087] In this detection circuit 75, the input signal of the charge amplifier 751 is the signal obtained by adding the first detection signal and the fourth detection signal. Since the first and fourth detection signals are signals with the same polarity and in phase, the amplitude of the input signal of the charge amplifier 751 is the sum of the amplitudes of the first and fourth detection signals. Similarly, the input signal of the charge amplifier 752 is the signal obtained by adding the second and third detection signals. Since the second and third detection signals are signals with the same polarity and in phase, the amplitude of the input signal of the charge amplifier 752 is the sum of the amplitudes of the second and third detection signals.

[0088] Furthermore, the input signals of charge amplifier 751 and charge amplifier 752 are in opposite phases with opposite polarities. Therefore, according to the detection circuit 75, compared to the conventional configuration where a fixed potential is supplied to the second and fourth detection electrodes E4 and E6, and only the first detection signal is input to charge amplifier 751 and only the third detection signal is input to charge amplifier 752, if the structure of the angular velocity sensor element 5 is the same, the amount of charge (current) input to the detection circuit 75 increases when the same angular velocity ωz is detected, thus improving the detection sensitivity of angular velocity ωz. As a result, the S / N ratio of the output signal of the detection circuit 75 is improved, and low noise can be achieved. In addition, due to the increased detection sensitivity, the temperature characteristics of the output signal of the detection circuit 75 are relatively reduced. Therefore, a high-precision and highly stable physical quantity detection device 1 can be realized.

[0089] The physical quantity detection device 1 has been described above. Next, the manufacturing method of the angular velocity sensor element 5 will be described. Figure 16 As shown, the manufacturing method of the angular velocity sensor element 5 includes: a substrate preparation step S1 for preparing a vibration substrate 500, a metal film forming step S2 for forming a metal film E on the vibration substrate 500, and an electrode forming step S3 for patterning the metal film E to form an electrode.

[0090] -Substrate preparation process S1-

[0091] In the substrate preparation process, photolithography and etching techniques are used to pattern the Z-cut crystal substrate, thereby, as... Figure 17 As shown, a vibrating substrate 500 is formed. It should be noted that, as an etching technique, dry etching, wet etching, etc., can be used.

[0092] - Metal film formation process S2 -

[0093] In the metal film formation process S2, film formation techniques such as evaporation and sputtering are used, for example... Figure 18 As shown, the metal film E is formed over the entire surface area of ​​the vibrating substrate 500.

[0094] - Electrode forming process S3 -

[0095] In electrode formation step S3, firstly, photoresist is deposited on the metal film E. It should be noted that the photoresist can be either a negative pattern where the photosensitive portion becomes a negative pattern, or a positive pattern where the non-photosensitive portion becomes a positive pattern. Next, the photoresist is exposed using a photomask. That is, if the photoresist is positive, the desired portion is exposed; conversely, if the photoresist is negative, the unwanted portion is exposed. Next, the photoresist is immersed in a developing solution to develop it, and the unwanted portions are removed. Through the above, as... Figure 19 As shown, a mask M corresponding to the electrode pattern is formed on a metal film E.

[0096] Here, as mentioned earlier, for the angular velocity sensor element 5, it is not necessary to remove the metal film E from the vibrating substrate 500 on the side facing the positive X-axis direction and the side facing the negative X-axis direction. This is achieved by forming the first protrusion 591 and the second protrusion 592 on the side of the base 50 facing the X-axis direction, and by distributing the first and second wiring separation portions G1 and G2 on the side of the first protrusion 591 and the second protrusion 592 facing the Y-axis direction.

[0097] With this configuration, since exposure of the side facing the positive X-axis and the side facing the negative X-axis is unnecessary, the number of photoresist exposures can be reduced. Specifically, the process can be completed in a total of four exposures: exposing the photoresist on the upper surface of the vibrating substrate 500 using exposure from the positive Z-axis, exposing the photoresist on the lower surface of the vibrating substrate 500 using exposure from the negative Z-axis, exposing the photoresist on the side of the vibrating substrate 500 facing the positive Y-axis using exposure from the positive Y-axis, and exposing the photoresist on the side of the vibrating substrate 500 facing the negative Y-axis using exposure from the negative Y-axis. Therefore, the manufacture of the angular velocity sensor element 5 is simplified.

[0098] Next, the metal film E is etched using a mask M to remove unwanted portions (those protruding from the mask M). As a result, electrodes E1 to E7 and terminals T1 to T6 are formed on the vibrating substrate 500. Specifically, by removing the metal film E on the negative Y-axis side of the first protrusion 591, the fourth detection electrode E6 is separated from the drive constant potential electrode E2; and by removing the metal film E on the positive Y-axis side of the second protrusion 592, the second detection electrode E4 is separated from the drive constant potential electrode E2. Finally, the mask M is removed from the metal film E. Through these steps, the angular velocity sensor element 5 is obtained.

[0099] According to the manufacturing method of this angular velocity sensor element 5, any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 is difficult to approach the drive electrode E1, which can effectively reduce their capacitive coupling. Therefore, the drive signal applied to the drive electrode E1 is less likely to be mixed into the detection signals taken from the first to fourth detection electrodes E3 to E6, and a detection signal with less noise can be obtained. Therefore, an angular velocity sensor element 5 capable of detecting angular velocity ωz with higher accuracy can be realized.

[0100] The physical quantity detection device 1 has been described above. As previously described, the angular velocity sensor element 5 of this physical quantity detection device 1 includes: a vibrating substrate 500, having a base 50, a plurality of vibrating arms connected to the base 50, and a protrusion 59 protruding from the side of the base 50; and a first detection electrode E3, a second detection electrode E4, a third detection electrode E5, a fourth detection electrode E6, a driving electrode E1, and a driving constant potential electrode E2, disposed in any one of the plurality of vibrating arms. Furthermore, a wiring separation section G is disposed on the side of the protrusion 59 to separate any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 from the driving constant potential electrode E2. Moreover, when viewed from above the base 50, the driving electrode E1 is disposed on the side of the protrusion 59 opposite to the side of the wiring separation section G. With this configuration, any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 is difficult to approach the drive electrode E1, effectively reducing their capacitive coupling. Therefore, the drive signal applied to the drive electrode E1 is less likely to be mixed into the detection signals taken from the first to fourth detection electrodes E3 to E6, resulting in a detection signal with low noise. Thus, an angular velocity sensor element 5 capable of detecting angular velocity ωz with higher accuracy can be realized.

[0101] Furthermore, as described above, the protrusion 59 has a first protrusion 591 and a second protrusion 592, and the wiring separation section G has a first wiring separation section G1 disposed on the first protrusion 591 and separating the second detection electrode E4 from the driving constant potential electrode E2, and a second wiring separation section G2 disposed on the second protrusion 592 and separating the fourth detection electrode E6 from the driving constant potential electrode E2. The first wiring separation section G1 is located on the side of the first protrusion 591 opposite to the second protrusion 592, and the second wiring separation section G2 is located on the side of the second protrusion 592 opposite to the first protrusion 591. With this configuration, it is possible to effectively suppress the proximity of the driving electrode E1 and the second detection electrode E4, and effectively reduce their capacitive coupling. Furthermore, it is possible to effectively suppress the proximity of the driving electrode E1 and the fourth detection electrode E6, and effectively reduce their capacitive coupling.

[0102] Furthermore, as previously described, the protrusion 59 has a third protrusion 593 and a fourth protrusion 594 disposed on the side opposite to the first protrusion 591 and the second protrusion 592 relative to the base 50. With this configuration, since the protrusion 59 can be disposed in a well-balanced manner relative to the base 50, deviation of the center of gravity from the center O can be effectively suppressed. Therefore, it is possible to suppress the decrease in vibration balance of the angular velocity sensor element 5 in the drive vibration mode described later.

[0103] Furthermore, as previously described, the plurality of vibrating arms includes a first detection arm 51 and a second detection arm 52 connected to the base 50. The first detection arm 51 is equipped with a first detection electrode E3 and a second detection electrode E4, and the second detection arm 52 is equipped with a third detection electrode E5 and a fourth detection electrode E6. With this configuration, the angular velocity ωz can be detected with high precision based on a first detection signal taken from the first detection electrode E3, a second detection signal taken from the second detection electrode E4, a third detection signal taken from the third detection electrode E5, and a fourth detection signal taken from the fourth detection electrode E6.

[0104] In addition, as mentioned above, the plurality of vibrating arms include a first connecting arm 53 and a second connecting arm 54 connected to the base 50, a first driving arm 55 and 56 connected to the first connecting arm 53, and a second driving arm 57 and 58 connected to the second connecting arm 54. A driving electrode E1 and a driving constant potential electrode E2 are respectively disposed in the first driving arm 55 and 56 and the second driving arm 57 and 58. Furthermore, the vibration substrate 500 includes a base 50, a first detection arm 51 extending from the base 50 in a first direction (Y-axis direction) to one side, a second detection arm 52 extending from the base 50 in the other direction (Y-axis direction), a first connecting arm 53 extending from the base 50 in a second direction orthogonal to the Y-axis direction (X-axis direction) to one side, a second connecting arm 54 extending from the base 50 in the other direction (X-axis direction), a pair of first drive arms 55 and 56 extending from the first connecting arm 53 in the Y-axis direction to one side and the other side, respectively, and a pair of second drive arms 57 and 58 extending from the second connecting arm 54 in the Y-axis direction to one side and the other side, respectively. With this configuration, the angular velocity sensor element 5 exhibits excellent vibration balance, thereby enabling high-precision detection of the angular velocity ωz.

[0105] Furthermore, as described above, the physical quantity detection device 1 includes: an angular velocity sensor element 5 as a physical quantity detection element; and a circuit element 7, including a drive circuit 79 for driving the angular velocity sensor element 5 and a detection circuit 75 for detecting the angular velocity ωz as a physical quantity based on the detection signal from the angular velocity sensor element 5. With this configuration, since the effects of the aforementioned angular velocity sensor element 5 can be enjoyed, a physical quantity detection device 1 capable of detecting the angular velocity ωz with high precision can be realized.

[0106] Furthermore, as described above, the manufacturing method of the angular velocity sensor element 5 includes: a substrate preparation step S1, preparing a vibrating substrate 500, wherein the vibrating substrate 500 has a base 50, a plurality of vibrating arms connected to the base 50, and a protrusion 59 protruding from the side of the base 50; a metal film formation step S2, forming a metal film E on the vibrating substrate 500; and an electrode formation step S3, patterning the metal film E to form a first detection electrode E3, a second detection electrode E4, a third detection electrode E5, a fourth detection electrode E6, a driving electrode E1, and a driving constant potential electrode E2. In the electrode formation step S3, by removing the metal film E located on the side of the protrusion 59, any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 is separated from the driving constant potential electrode E2. According to this manufacturing method, any one of the first detection electrode E3, the second detection electrode E4, the third detection electrode E5, and the fourth detection electrode E6 is difficult to approach the drive electrode E1, effectively reducing their capacitive coupling. Therefore, the drive signal applied to the drive electrode E1 is less likely to be mixed into the detection signals taken from the first to fourth detection electrodes E3 to E6, resulting in a detection signal with less noise. Thus, an angular velocity sensor element 5 capable of detecting angular velocity ωz with higher accuracy can be realized.

[0107] Second Implementation Method

[0108] Figure 20 This is a flowchart illustrating the manufacturing process of the angular velocity sensor element according to the second embodiment. Figure 21 This is a top view used to illustrate the manufacturing method of an angular velocity sensor element.

[0109] In this embodiment, except for the manufacturing method of the angular velocity sensor element 5, it is the same as the physical quantity detection device 1 of the first embodiment described above. It should be noted that in the following description, this embodiment will be described primarily for its differences from the aforementioned embodiments, and descriptions of identical items will be omitted. Furthermore, in the figures of this embodiment, the same reference numerals are used for components that are the same as in the aforementioned embodiments.

[0110] like Figure 20 As shown, the manufacturing method of the angular velocity sensor element 5 in this embodiment also includes a protrusion removal step S4, which removes the protrusion 59 after the electrode formation step S3. Since the steps up to the electrode formation step S3 are the same as those in the first embodiment described above, only the protrusion removal step S4 will be described below.

[0111] - Protrusion Removal Process S4 -

[0112] In the protrusion removal process S4, such as Figure 21 As shown, the first, second, third, and fourth protrusions 591, 592, 593, and 594 are removed. Thus, by removing the first protrusion 591, even if the formation of the first wiring separation section G1 is incomplete, preventing the separation of the fourth detection electrode E6 from the drive constant potential electrode E2, reliably separation is achieved. Similarly, by removing the second protrusion 592, even if the formation of the second wiring separation section G2 is incomplete, preventing the separation of the second detection electrode E4 from the drive constant potential electrode E2, reliably separation is achieved. Therefore, the yield of the angular velocity sensor element 5 can be improved. Furthermore, by removing the third and fourth protrusions 593 and 594, the decrease in vibration balance of the angular velocity sensor element 5 can be suppressed.

[0113] In summary, the manufacturing method of the angular velocity sensor element 5 of this embodiment includes a protrusion removal step S4, which removes the protrusion 59, performed after the electrode formation step S3. According to this method, the yield of the angular velocity sensor element 5 can be improved.

[0114] This second implementation method can achieve the same effect as the first implementation method described above.

[0115] The physical quantity detection element, physical quantity detection device, and manufacturing method of the physical quantity detection element of the present invention have been described above based on the illustrated embodiments. However, the present invention is not limited thereto, and the configuration of each part can be replaced with any configuration having the same function. In addition, each process can be replaced with any process having the same function. Furthermore, any configuration or process thereof can be added to the present invention. In addition, the various embodiments can be appropriately combined.

[0116] Furthermore, in the aforementioned embodiments, an angular velocity sensor element that detects angular velocity ωz is used as a physical quantity detection element; however, it is not limited to this. For example, the physical quantity detection element may also be an angular velocity sensor element that detects angular velocity about the X-axis or an angular velocity sensor element that detects angular velocity about the Y-axis. In addition, the detected physical quantity is not limited to angular velocity, and may also be acceleration, pressure, etc.

Claims

1. A physical quantity detection element, characterized in that, include: A vibrating substrate includes a base, a plurality of vibrating arms connected to the base, and a protrusion extending from the side of the base; as well as The first detection electrode, the second detection electrode, the third detection electrode, the fourth detection electrode, the driving electrode, and the driving constant potential electrode are disposed in any one of the plurality of vibrating arms. A wiring separation section is disposed on the side of the protrusion, which separates any one of the first detection electrode, the second detection electrode, the third detection electrode, and the fourth detection electrode from the driving constant potential electrode. When viewed from above, the driving electrode is positioned on the side of the protrusion opposite to the side of the wiring separation portion.

2. The physical quantity detection element according to claim 1, characterized in that, The protrusion has a first protrusion and a second protrusion. The wiring separation section includes: A first wiring separation portion is disposed on the first protrusion portion, and separates the second detection electrode from the driving constant potential electrode; and A second wiring separation section is disposed on the second protrusion and separates the fourth detection electrode from the driving constant potential electrode. The first wiring separation part is located on the side of the first protrusion opposite to the second protrusion. The second wiring separation part is located on the side of the second protrusion opposite to the first protrusion.

3. The physical quantity detection element according to claim 2, characterized in that, The protrusions include a third protrusion and a fourth protrusion disposed relative to the base on the side opposite to the first protrusion and the second protrusion.

4. The physical quantity detection element according to claim 3, characterized in that, The plurality of vibrating arms includes a first detection arm and a second detection arm connected to the base. The first detection electrode and the second detection electrode are disposed on the first detection arm. The third detection electrode and the fourth detection electrode are disposed on the second detection arm.

5. The physical quantity detection element according to claim 4, characterized in that, The plurality of vibrating arms includes: a first connecting arm and a second connecting arm connected to the base; a first drive arm connected to the first connecting arm; and a second drive arm connected to the second connecting arm. The driving electrode and the driving constant potential electrode are respectively disposed on the first driving arm and the second driving arm. The vibrating substrate includes: The base; The first detection arm extends from the base to one side in the first direction; The second detection arm extends from the base to the other side in the first direction; The first connecting arm extends from the base toward a second direction orthogonal to the first direction; The second connecting arm extends from the base to the other side in the second direction; A pair of first drive arms extending from the first connecting arm to one side and the other side in the first direction, respectively; and A pair of second drive arms extending from the second connecting arm to one side and the other side of the first direction, respectively.

6. A physical quantity detection device, characterized in that, include: The physical quantity detection element according to any one of claims 1 to 5; as well as The circuit element includes a driving circuit and a detection circuit, wherein the driving circuit drives the physical quantity detection element, and the detection circuit detects the physical quantity based on a detection signal from the physical quantity detection element.

7. A method for manufacturing a physical quantity detection element, characterized in that, include: The substrate preparation process prepares a vibrating substrate, wherein the vibrating substrate includes a base, a plurality of vibrating arms connected to the base, and a protrusion extending from the side of the base; The metal film formation process involves forming a metal film on the vibrating substrate; and In the electrode forming process, the metal film is patterned to form a first detection electrode, a second detection electrode, a third detection electrode, a fourth detection electrode, a driving electrode, and a driving constant potential electrode. In the electrode forming process, the metal film located on the side of the protrusion is removed to separate any one of the first detection electrode, the second detection electrode, the third detection electrode, and the fourth detection electrode from the driving constant potential electrode.

8. The method for manufacturing a physical quantity detection element according to claim 7, characterized in that, This includes a protrusion removal process performed after the electrode forming process to remove the protrusion.

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