ACCELERATION SENSOR

Abstract

An accelerometer comprises a device-side substrate with a first main surface and a second main surface opposite the first main surface, a recessed section extending from the first main surface towards the second main surface, a MEMS electrode provided in the recessed section comprising a fixed electrode with a first fixed electrode and a second fixed electrode electrically isolated from the first fixed electrode, and a movable electrode with a first movable electrode and a second movable electrode electrically isolated from the first movable electrode, forming a differential circuit, wherein an insulating joining connection mechanically connects the first movable electrode and the second movable electrode while simultaneously electrically isolating the first movable electrode and the second movable electrode.

Description

TECHNICAL AREA

[0001] The present invention relates to an acceleration sensor. STATE OF THE ART:

[0002] Patent document 1 discloses a capacitive MEMS accelerometer (hereinafter referred to as the accelerometer). The accelerometer includes a capacitor with a fixed and a movable electrode and detects a change in the capacitance of one of the capacitors caused by the displacement of the movable electrode when subjected to acceleration. The acceleration is calculated based on the detected change in the capacitor's capacitance.

[0003] A fully differential accelerometer is known as an accelerometer. The fully differential accelerometer includes two proof masses, a first movable electrode and a second movable electrode, each connected to the two proof masses, as well as a first fixed electrode and a second fixed electrode. The first through fourth capacitors are constructed from a combination of the first and second movable electrodes and the first and second fixed electrodes.

[0004] In a differential acceleration sensor, two symmetrical output voltages are detected when an acceleration is applied. These two output voltages can include common-mode noise and an offset (hereinafter collectively referred to as common-mode noise and the like). However, by obtaining a difference between the two output voltages, an output can be obtained in which the common-mode noise and the like are suppressed or canceled out, and the acceleration can be accurately calculated based on the output. Patent documents

[0005] Patent Document 1: JP 2019-49434 A SUMMARY Problems to be solved by the invention

[0006] The two test masses may each exhibit individual deviations, including variations in dimensions, shapes, and the like, and / or distortions or deformations, such as thermal deformation (hereinafter collectively referred to as "deviations"). Consequently, the two output voltages may each also include disturbances or noise caused by the individual deviations (hereinafter referred to as individual disturbances). Therefore, if a difference is obtained between two output voltages, the individual disturbances do not cancel each other out, and thus the acceleration cannot be calculated accurately in some cases.

[0007] One objective of the present disclosure is to provide an accelerometer that is capable of improving the accuracy of acceleration calculations. Solutions to the problems

[0008] One aspect of the present disclosure provides an accelerometer which includes the following: a substrate with a first main surface and a second main surface facing the first main surface; a recessed section that extends from the first main surface towards the second main surface side; a MEMS electrode provided in the recessed section, comprising a fixed electrode with a first fixed electrode and a second fixed electrode electrically isolated from the first fixed electrode, and a movable electrode with a first movable electrode and a second movable electrode electrically isolated from the first movable electrode; an insulating joint that mechanically connects the first movable electrode and the second movable electrode while simultaneously electrically isolating the first movable electrode and the second movable electrode.

[0009] According to the present disclosure, since the first movable electrode and the second movable electrode are mechanically connected to each other and simultaneously electrically insulated via the insulating joint, two movable electrodes with different potentials can be enclosed in a test mass that is displaced as a single unit. Consequently, individual deviations occur jointly in the first and second movable electrodes, and thus, by achieving a difference between the two obtained output voltages, in addition to eliminating common-mode interference and the like, outputs are also obtained in which individual disturbances caused by individual deviations cancel each other out. Therefore, the accuracy of the acceleration calculation can be improved based on an output in which common-mode interference and the like, as well as individual disturbances, are suppressed. Effects of the invention

[0010] According to the accelerometer of the present disclosure, the accuracy of the acceleration calculation can be improved. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a top view of an acceleration sensor according to a first embodiment of the present disclosure; Fig. Figure 2 is a top view of a main part, which contains a MEMS electrode of the accelerometer. Fig. 1 shows; Fig. Figure 3 is an enlarged top view showing the edge of a first area of Fig. 2 shows; Fig. 4 is a cross-sectional view along the in Fig. 3 shown line IV-IV; Fig. 5 is a cross-sectional view along the in Fig. 3 shown line VV; Fig. 6 is a cross-sectional view along the in Fig. 3 shown line VI-VI; Fig. 7 is a cross-sectional view along the in Fig. 3 shown line VII-VII; Fig. 8A is a simplified element diagram representing the accelerometer of Fig. 1. Illustrated in a simplified way; Fig. 8B is a corresponding circuit diagram of Fig. 8A; Fig. 8C is a corresponding circuit diagram in which Fig. 8B is simplified; Fig. Figure 9 is a top view illustrating the MEMS electrode of the accelerometer according to a second embodiment of the present disclosure; Fig. 10 is an enlarged top view showing an X1 side of Fig. 9 illustrates; Fig. 11 is a cross-sectional view along the in Fig. 10 shown line XI-XI; Fig. 12 is a cross-sectional view along the in Fig. 10 shown line XII-XII; Fig. 13 is a cross-sectional view along the in Fig. 10 shown line XIII-XIII; Fig. Figure 14 is an enlarged top view showing an X2 side of Fig. 9 illustrates; Fig. 15 is a cross-sectional view along the in Fig. 14 shown line XV-XV; Fig. Figure 16 is a top view illustrating the MEMS electrode of the accelerometer according to a third embodiment of the present disclosure; Fig. 17 is an enlarged top view showing the edge of a first area of Fig. 16 shows; Fig. 18 is a cross-sectional view along the in Fig. 17 shown line XVIII-XVIII; Fig. 19 is a cross-sectional view along the in Fig. 17 shown line XIX-XIX; Fig. 20 is a cross-sectional view along the in Fig. 17 shown line XX-XX; Fig. Figure 21 is a top view illustrating the MEMS electrode of the accelerometer according to a fourth embodiment of the present disclosure; and Fig. Figure 22 is a top view illustrating the MEMS electrode of the accelerometer according to a fifth embodiment of the present disclosure. DETAILED DESCRIPTION

[0011] An acceleration sensor according to one embodiment of the present disclosure is described below with reference to the accompanying drawings. It should be noted that the following description is merely exemplary and is not intended to limit the present invention, its application, or its use. [First embodiment](overall configuration)

[0012] Fig. Figure 1 is a schematic top view illustrating an acceleration sensor 1 according to a first embodiment of the present disclosure. The acceleration sensor 1 is a uniaxial acceleration sensor that detects acceleration in a uniaxial direction. As shown in Fig. As illustrated in Figure 1, the accelerometer 1 includes a device-side substrate 2 with a rectangular shape in plan view, a sensor unit 3 arranged in a central section of the device-side substrate 2, an electrode pad 4 arranged on one side of the sensor unit 3 in the device-side substrate 2, and a cover-side substrate 5. It should be noted that, although the size of the accelerometer 1 is not limited according to the present disclosure, the accelerometer 1 is designed to be relatively small by using a so-called micro-electro-machining system (MEMS) technique.

[0013] The device-side substrate 2 is made of conductive silicon and comprises a first main surface 2a, to which the lid-side substrate 5 is bonded, and a second main surface 2b (see Fig. 4) one, which is located on one of the sides opposite and facing the first main surface 2a. The following is done in Fig. 1. The description assumes that a left-right direction is an X-direction, a vertical or up-down direction is a Y-direction, and a direction orthogonal to both the X-direction and the Y-direction is a Z-direction. More precisely, in the X-direction, the right side is... Fig. The left side is designated as the X1 side, the right side is designated as the X2 side, and in the Y direction the top side is designated as Fig. The first side is designated as Y1-side and the lower side is designated as Y2-side. Furthermore, as in the Fig. Figures 4 to 7 illustrate that, in the Z direction, the side of the first main surface 2a is called the Z1 side and the side of the second main surface 2b is called the Z2 side. (Sensor unit configuration)

[0014] Fig. Figure 2 is an enlarged top view showing an edge of the sensor unit 3, with the cover-side substrate 5 of Fig. 1 is away. As in Fig. As illustrated in Figure 2, the sensor unit 3 includes a recessed section 10 formed in the device-side substrate 2, a MEMS electrode 6 located in the recessed section, and a frame 90 that supports the MEMS electrode 6. The MEMS electrode 6 and the frame 90 are formed by machining the device-side substrate 2, which is made of conductive silicon, using a MEMS technique.

[0015] The recessed section 10 is designed such that it extends from the first main surface 2a towards the second main surface 2b. In plan view, the recessed section 10 has a rectangular shape and is defined by a plurality of wall surfaces 11 of the recessed section.A multitude of the wall surfaces 11 of the recessed section include a bottom surface 12 of the recessed section located on the Z2 side, and in the bottom surface 12 of the recessed section a first side surface 13 of the recessed section extending from an edge section of the X1 side towards the Z1 side, a second side surface 14 of the recessed section extending from an edge section of the Y1 side towards the Z1 side, a third side surface 15 of the recessed section extending from an edge section of the X2 side towards the Z1 side, and a fourth side surface 16 of the recessed section extending from an edge section of the Y2 side towards the Z1 side.

[0016] The recessed section 10 is subdivided in plan view into a first region S1, a second region S2, a third region S3, and a fourth region S4 by an X-direction centerline O1, which passes through the center point in the X direction and extends in the Y direction, and a Y-direction centerline O2, which passes through the center point in the Y direction and extends in the X direction. An intersection of the X-direction centerline O1 and the Y-direction centerline O2 is called the center and center point O, respectively (see figure). Fig. 1) of the excavated section 10 (the ground surface 12 of the excavated section) defined.

[0017] Specifically, the first area S1 is located on the X1 side with respect to the X-direction centerline O1 and on the Y1 side with respect to the Y-direction centerline O2. The second area S2 is located on the X1 side with respect to the X-direction centerline O1 and on the Y2 side with respect to the Y-direction centerline O2. The third area S3 is located on the X2 side with respect to the X-direction centerline O1 and on the Y1 side with respect to the Y-direction centerline O2. The fourth area S4 is located on the X2 side with respect to the X-direction centerline O1 and on the Y2 side with respect to the Y-direction centerline O2. (MEMS electrode configuration)

[0018] The MEMS electrode 6 includes a fixed electrode 7 and a movable electrode 8, which has a comb shape. The fixed electrode 7 includes a first fixed electrode 20 and a second fixed electrode 30, which is electrically insulated from the first fixed electrode 20. The movable electrode 8 includes a first movable electrode 40 and a second movable electrode 50, which is electrically insulated from the first movable electrode 40. An insulating film 18 (see the cross-sectional view of the respective electrodes) Fig. 4 to 7), which is made from an oxide film (for example silicon oxide), is laminated onto a surface on the Z1 side of the fixed electrode 7 and the movable electrode 8.

[0019] The first fixed electrode 20 is located in the first region S1 and in the fourth region S4. The second fixed electrode 30 is located in the second region S2 and in the third region S3. That is, the first fixed electrodes 20 and the second fixed electrodes 30 are each arranged in regions that are diagonally across the center point O. On the other hand, the first and second movable electrodes 40 and 50 are each arranged in the first to fourth regions S1 to S4.

[0020] Fig. Figure 3 is an enlarged top view illustrating an edge of the first area S1 of the sensor unit 3. First, with reference to Fig. 3 describes a configuration of the MEMS electrode 6 in the first region S1. In the first region S1, the first solid electrode 20 includes a plurality of first solid electrode elements 21 extending in the Y direction and arranged in the X direction, a base section 22 of the first solid electrode connected to a Y1-side end section of a plurality of first solid electrode elements 21 extending in the X direction, and an extension section 23 of the first solid electrode extending from an end section on the X1 side of the base section 22 of the first solid electrode to the Y2 side in the direction of the Y-direction center line O2.

[0021] The first movable electrode 40 includes a plurality of first movable electrode elements 41 extending in the Y direction and arranged in the X direction. The second movable electrode 50 includes a plurality of second movable electrode elements 51 extending in the Y direction and arranged in the X direction. The first and second movable electrode elements 41 and 51 are arranged alternately in the X direction. In the first region S1, the first movable electrode element 41 and the second movable electrode element 51 located on the X1 side adjacent to the first movable electrode element 41 are connected such that they form a first set of movable electrode elements 8A.

[0022] An insulating joining compound 9 serves to connect the first movable electrode element 41 and the second movable electrode element 51. The insulating joining compound 9 is, for example, silicon oxide formed by thermal oxidation of conductive silicon, and connects the two mechanically while electrically isolating them.

[0023] In the first region S1, a plurality of the first fixed electrode elements 21 and a plurality of the movable electrode elements 8A of the first set are arranged alternately in the X-direction and are opposite each other. Therefore, in the first region S1, the first movable electrode element 41 is located on the X1 side of the first fixed electrode element 21, and the second movable electrode element 51 is located on the X2 side of the first fixed electrode element 21. In the first region S1, the first fixed electrode element 21 and the first movable electrode element 41 form a first capacitor C1. Furthermore, the first fixed electrode element 21 and the second movable electrode element 51 form a second capacitor C2.

[0024] In the first region S1, the movable electrode 8 further includes a first section 61 of the first conductive path, which is connected via the insulating joint 9 to a Y2-side end section of a plurality of the movable electrode elements 8A of the first set and extends in the X direction over the first and third regions S1 and S3. The first conductive path section 61 includes a first section 62 of the first conductive path, located on the Y1 side, and a second section 63 of the first conductive path, located on the Y2 side. The first section 62 of the first conductive path and the second section 63 of the first conductive path are connected via the insulating joint 9.

[0025] In the present embodiment, the first conductive path section 61 is configured in a conductor-like manner, such that a section extending in the X direction in three rows and a section extending from each of the first and second movable electrode elements 41 and 51 to the Y2 side intersect, two rows on the Y1 side form the first section 62 of the first conductive path and one row on the Y2 side forms the second section 63 of the first conductive path.

[0026] The first movable electrode element 41 and the first section 62 of the first conductive path are electrically connected via a first wiring layer 42. Fig. Figure 4 is a cross-sectional view along the first wiring layer 42 in the Fig. 3 shown line IV-IV. As in Fig. As illustrated in Figure 4, the first wiring layer 42 is formed on the insulating film 18, which is laminated onto a surface on the Z1 side of the first movable electrode element 41 and the first section 62 of the first conductive path, and is electrically connected to the first movable electrode element 41 and the first section 62 of the first conductive path via a first contact 43 that penetrates the insulating film 18 in the Z direction.

[0027] They are similar to those in Fig. Figure 3 illustrates that the second movable electrode element 51 and the second section 63 of the first conductive path are electrically connected via a second wiring layer 52. The second wiring layer 52 is formed on the insulating film 18, which is laminated onto a surface on the Z-side of the second movable electrode element 51 and the second section 63 of the first conductive path, and is connected via a second contact 53 (see Figure 3). Fig. 5), which penetrates the insulating film 18 in the Z direction, is electrically connected to the second movable electrode element 51 and the second section 63 of the first conductive path.

[0028] The first wiring layer 42 is formed at a position corresponding to the first movable electrode element 41 in the X-direction. The second wiring layer 52 is formed at a position corresponding to the second movable electrode element 51 in the X-direction. Therefore, the first wiring layer 42 and the second wiring layer 52 are arranged alternately in the X-direction. The first and second wiring layers 42 and 52 are made of conductive metal, for example, aluminum.

[0029] The movable electrode 8 further includes a first spring section 71, which is connected to an X1-side end section of the first conductive path section 61 and is configured to be elastically deformable in the X direction. The first spring section 71 is electrically conductive and mechanically connected to the first section 62 of the first conductive path of the first conductive path section 61. The first spring section 71 is located between the first fixed electrode element 21, which is located closest to the X1 side among a plurality of first fixed electrode elements 21, and the extension section 23 of the first fixed electrode.

[0030] The movable electrode 8 further includes a base section 76 of the first conductive path, which is conductively and mechanically connected to the X1 side of the first spring section 71. In the base section 76 of the first conductive path, a tip section of the extension section 23 of the first fixed electrode is connected to the Y1 side via the insulating joint 9.

[0031] Next, a configuration of the MEMS electrode 6 in the second area S2 will be described with reference to the Fig. 2 and Fig. 3 described. In the second region S2, the second solid electrode 30 includes a plurality of second solid electrode elements 31 extending in the Y direction and arranged in the X direction, a base section 32 of the second solid electrode connected to a Y2-sided end section of a plurality of the second solid electrode elements 31 extending in the X direction, and an extension section 33 of the second solid electrode extending from an end section on the X1 side of the base section 32 of the second solid electrode to the Y1 side in the direction of the Y-direction center line O2.

[0032] In the second region S2, similar to the first region S1, the first and second movable electrode elements 41 and 51 are arranged alternately in the X-direction; however, the arrangement sequence of the first and second movable electrode elements 41 and 51 differs from that in the first region S1. In particular, in the second region S2, the first movable electrode element 41 and the second movable electrode element 51, located on the X2 side next to the first movable electrode element 41, form a movable electrode element 8B of a second set, which is mechanically connected via the insulating joint 9.

[0033] A large number of the movable electrode elements 8B of the second set are positioned in locations corresponding to the movable electrode elements 8A of the first set in the first region S1 in the X-direction. That is, the first movable electrode element 41 in the first region S1 and the second movable electrode element 51 in the second region S2 are opposite each other in the Y-direction across the Y-direction center line O2. Furthermore, the second movable electrode element 51 in the first region S1 and the first movable electrode element 41 in the second region S2 are opposite each other in the Y-direction across the Y-direction center line O2.

[0034] In the second region S2, a plurality of the second fixed electrode elements 31 and a plurality of the second set's movable electrode elements 8B are arranged alternately in the X-direction and are opposite each other. Therefore, in the second region S2, the first movable electrode element 41 is located on the X2 side of the second fixed electrode element 31, and the second fixed electrode element 31 and the first movable electrode element 41 form a third capacitor C3. Furthermore, the second movable electrode element 51 is located on the X1 side of the second fixed electrode element 31, and the second fixed electrode element 31 and the second movable electrode element 51 form a fourth capacitor C4.

[0035] In the second region S2, the movable electrode 8 further includes a second conductive path section 65, which is connected via the insulating joint 9 to a Y1-side end section of a plurality of the movable electrode elements 8B of the second set and extends in the X direction over the second and fourth regions S1 and S4. The second conductive path section 65 includes a first section 66 of the second conductive path, located on the Y1 side, and a second section 67 of the second conductive path, located on the Y2 side. The first section 66 and the second section 67 of the second conductive path are connected via the insulating joint 9.

[0036] In the present embodiment, the second conductive path section 65 is configured in a conductor-like manner, such that a section extending in three rows in the X direction and a section extending from each of the first and second fixed electrode elements 21 and 31 to the Y1 side intersect, one row on the Y1 side forms the first section 66 of the second conductive path and two rows on the Y2 side form the second section 67 of the second conductive path.

[0037] The first movable electrode element 41 and the first section 66 of the second conductive path are electrically connected via a third wiring layer 44. As shown in Fig. As illustrated in Figure 4, the third wiring layer 44 is formed on the insulating film 18, which is laminated onto a surface on the Z1 side of the first movable electrode element 41 and the first section 66 of the second conductive path, and is electrically connected to the first movable electrode element 41 and the first section 66 of the second conductive path via a third contact 45 that penetrates the insulating film 18 in the Z direction.

[0038] They are similar to those in Fig. Figure 3 illustrates that the second movable electrode element 51 and the second section 67 of the second conductive path are electrically connected via a fourth wiring layer 54. The fourth wiring layer 54 is formed on the insulating film 18, which is laminated onto a surface on the Z-side of the second movable electrode element 51 and the second section 67 of the second conductive path, and is connected via a fourth contact 55 (see Figure 3). Fig. 5), which penetrates the insulating film 18 in the Z direction, is electrically connected to the second movable electrode element 51 and the second section 67 of the second conductive path.

[0039] The third wiring layer 44 is formed at a position corresponding to the first movable electrode element 41 in the X-direction. The fourth wiring layer 54 is formed at a position corresponding to the second movable electrode element 51 in the X-direction. Therefore, the third wiring layer 44 and the fourth wiring layer 54 are arranged alternately in the X-direction. The third and fourth wiring layers 44 and 54 are made of conductive metal, for example, aluminum.

[0040] The movable electrode 8 further includes a second spring 72, which is connected to an X1-side end section of the second conductive path section 65 and is configured to be elastically deformable in the X direction. The second spring section 72 is electrically conductive and mechanically connected to the second section 67 of the second conductive path of the second conductive path section 65. The second spring section 72 is located between the second fixed electrode element 31, which is located closest to the X1 side among a plurality of second fixed electrode elements 31, and the extension section 33 of the second fixed electrode.

[0041] The movable electrode 8 further includes a base section 78 of the second conductive path, which is conductively and mechanically connected to the X1 side of the second spring section 72. In the base section 78 of the second conductive path, a tip section of the extension section 33 of the second fixed electrode is connected to the Y2 side via the insulating joint 9.

[0042] Next, with reference to the Fig. 2 and Fig. Figure 3 describes a configuration of the MEMS electrode 6 in the third region S3. The second fixed electrode 30 is configured to be point-symmetric with respect to the center point O with the second fixed electrode 30 in the second region S2. The first and second movable electrode elements 41 and 51 are configured similarly to the first and second movable electrode elements 41 and 51 in the second region S2. As described above, in the third region S3, the first conductive path segment 61 extends in the X-direction from the first region S1 to the third region S3.

[0043] In particular, in the third region S3, the second fixed electrode 30 includes a plurality of the second fixed electrode elements 31 extending in the Y direction and arranged in the X direction, the base section 32 of the second fixed electrode, which is connected to a Y1-side end section of a plurality of the second fixed electrode elements 31 and extends in the X direction, and the extension section 33 of the second fixed electrode, which extends from an end section on the X2 side of the base section 32 of the second fixed electrode to the Y2 side in the direction of the Y-direction center line O2.

[0044] The first and second movable electrode elements 41 and 51 are arranged alternately in the X direction. In particular, in the third region S3, the first movable electrode element 41 and the second movable electrode element 51, located on the X2 side next to the first movable electrode element 41, form the movable electrode element 8B of the second set, which is mechanically connected via the insulating joint 9.

[0045] In the third region S3, a plurality of the second fixed electrode elements 31 and a plurality of the movable electrode elements 8B of the second set are arranged alternately in the X direction and are opposite each other. Therefore, in the third region S3, the first movable electrode element 41 is located on the X2 side of the second fixed electrode element 31, and the second fixed electrode element 31 and the first movable electrode element 41 form the third capacitor C3. Furthermore, the second movable electrode element 51 is located on the X1 side of the second fixed electrode element 31, and the second fixed electrode element 31 and the second movable electrode element 51 form a fourth capacitor C4.

[0046] In the third area S3, similar to the first area S1, each of the first movable electrode elements 41 is electrically connected to the first section 62 of the first conductive path via the first wiring layer 42, and each of the second movable electrode elements 51 is electrically connected to the second section 63 of the first conductive path via the second wiring layer 52.

[0047] The movable electrode 8 further includes a third spring section 73, which is connected to an X2-sided end section of the first conductive path section 61 and is configured to be elastically deformable in the X direction. The third spring section 73 is electrically conductive and mechanically connected to the first section 62 of the first conductive path of the first conductive path section 61. The third spring section 73 is located between the second fixed electrode element 31, which is located closest to the X2 side among a plurality of second fixed electrode elements 31, and the extension section 33 of the second fixed electrode.

[0048] The movable electrode 8 further includes the base section 76 of the first conductive path, which is conductively and mechanically connected to the X2 side of the third spring section 73. In the base section 76 of the first conductive path, a tip section of the extension section 33 of the second fixed electrode is connected to the Y1 side via the insulating joint 9.

[0049] Next, with reference to the Fig. 2 and Fig. 3 describes a configuration of the MEMS electrode 6 in the fourth region S4. The first fixed electrode 20 is configured to be point-symmetric with respect to the center point O with the first fixed electrode 20 in the first region S1. The first and second movable electrode elements 41 and 51 are configured similarly to the first and second movable electrode elements 41 and 51 in the first region S1. As described above, in the fourth region S4, the second conductive path segment 65 extends in the X-direction from the second region S2 to the fourth region S4.

[0050] In particular, in the fourth region S4, the first solid electrode 20 includes a plurality of first solid electrode elements 21 extending in the Y direction and arranged in the X direction, the base section 22 of the first solid electrode, which is connected to a Y2-sided end section of a plurality of first solid electrode elements 21 and extending in the X direction, and the extension section 23 of the first solid electrode, which extends from an end section on the X2 side of the base section 22 of the first solid electrode to the Y1 side in the direction of the Y-direction center line O2.

[0051] The first and second movable electrode elements 41 and 51 are arranged alternately in the X direction. In particular, in the fourth region S4, the first movable electrode element 41 and the second movable electrode element 51, located on the X1 side next to the first movable electrode element 41, form the movable electrode element 8A of the first set, which is mechanically connected via the insulating joint 9.

[0052] A large number of the movable electrode elements 8A of the first set are positioned in locations corresponding to the movable electrode elements 8B of the second set in the third region S3 in the X-direction. That is, the first movable electrode element 41 in the third region S3 and the second movable electrode element 51 in the fourth region S4 are opposite each other in the Y-direction across the Y-direction center line O2. Furthermore, the second movable electrode element 51 in the third region S3 and the first movable electrode element 41 in the fourth region S4 are opposite each other in the Y-direction across the Y-direction center line O2.

[0053] In the fourth region S4, a plurality of the first fixed electrode elements 21 and a plurality of the movable electrode elements 8A of the first set are arranged alternately in the X-direction and are opposite each other. Therefore, in the fourth region S4, the first movable electrode element 41 is located on the X1 side of the first fixed electrode element 21, and the first fixed electrode element 21 and the first movable electrode element 41 form the first capacitor C1. Furthermore, the second movable electrode element 51 is located on the X2 side of the first fixed electrode element 21, and the first fixed electrode element 21 and the second movable electrode element 51 form the second capacitor C2.

[0054] In the fourth region S4, similar to the second region S2, each of the first movable electrode elements 41 is electrically connected to the first section 66 of the second conductive path via the third wiring layer 44, and each of the second movable electrode elements 51 is electrically connected to the second section 67 of the second conductive path via the fourth wiring layer 54.

[0055] The movable electrode 8 further includes a fourth spring section 74, which is connected to an X2-sided end section of the second conductive path section 65 and is configured to be elastically deformable in the X direction. The fourth spring section 74 is electrically conductive and mechanically connected to the second section 67 of the second conductive path of the second conductive path section 65. The fourth spring section 74 is located between the first fixed electrode element 21, which is located closest to the X2 side among a plurality of first fixed electrode elements 21, and the extension section 23 of the first fixed electrode.

[0056] The movable electrode 8 further includes the base section 78 of the second conductive path, which is conductively and mechanically connected to the X2 side of the fourth spring section 74. In the base section 78 of the second conductive path, a tip section of the extension section 33 of the second fixed electrode is connected to the Y2 side via the insulating joint 9.

[0057] As in Fig. As illustrated in Figure 3, the first conductive path section 61 and the second conductive path section 65 are arranged such that they are separated from each other on both sides in the Y-direction across the X-direction center line O1. The first conductive path section 61 and the second conductive path section 65 are mechanically connected in the Y-direction by a connecting section 69 of the conductive path at a central section in the X-direction. The first conductive path section 61, the second conductive path section 65, and the connecting section 69 of the conductive path form an H-shaped conductive path section 60.

[0058] The connecting section 69 of the conductive path is located at the midpoint O and is configured to have a rectangular shape, elongated in the X-direction over a region extending across the first to fourth sections S1 to S4. The connecting section 69 of the conductive path is connected via the insulating joint 9 to each of the first conductive path section 61 and the second conductive path section 65.

[0059] In the connecting section 69 of the conductive path, a first wiring layer 64 of the connecting section, which electrically connects the first section 62 of the first conductive path and the first section 66 of the second conductive path, and a second wiring layer 68 of the connecting section, which electrically connects the second section 63 of the first conductive path and the second section 67 of the second conductive path, are formed. The first wiring layer 64 of the connecting section extends over the first and second regions S1 and S2 in the connecting section 69 of the conductive path and is formed at a position corresponding to the first movable electrode element 41 in the first region S1 in the X direction.The second wiring layer 68 of the connection section extends over the third and fourth regions S3 and S4 in the connection section 69 of the conductive path and is formed at a position corresponding to the second movable electrode element 51 in the fourth region S4 in the X direction.

[0060] Fig. Figure 5 is a cross-sectional view along the first wiring layer 64 of the connection section along the in Fig. Line VV shown in section 3. As in Fig. As illustrated in Figure 5, the first wiring layer 64 of the connecting section is formed on the insulating film 18, which is laminated onto the connecting section 69 of the conductive path, extends continuously towards the Y2 side to the first wiring layer 42, which is formed on the first section 62 of the first conductive path, and is electrically connected to the first section 66 of the second conductive path via a fifth contact 56.

[0061] Fig. Figure 6 is a cross-sectional view along the second wiring layer 68 of the connection section along the in Fig. 3 shown line VI-VI. As in Fig. As illustrated in Figure 6, the second wiring layer 68 of the connecting section is formed on the insulating film 18, which is laminated onto the connecting section 69 of the conductive path, extends continuously towards the Y1 side to the fourth wiring layer 54, which is formed on the second section 67 of the second conductive path, and is electrically connected to the second section 63 of the first conductive path via a sixth contact 57.

[0062] In the movable electrode 8, the H-shaped conductor track section 60 forms a test mass. That is, a plurality of the first movable electrode elements 41 and a plurality of the second movable electrode elements 51 are connected to a single test mass. (Frame configuration)

[0063] Next, the frame 90, which supports the MEMS electrode 6, is described. The MEMS electrode 6 is in a state where it is supported by the frame 90 and is free-floating from the bottom surface 12 of the recessed section 10. That is, it is separated from the bottom surface 12 of the recessed section in the direction of the Z1 side and is not rigidly connected to any of the first to fourth side surfaces 13 to 16 of the recessed section. Here, "rigidly connected" in this patent specification means that no connection is included that allows a certain degree of elastic displacement via an elastic element, such as a flexible conduit described later, but rather that there is a rigid connection that does not allow any active displacement.

[0064] As in Fig. Indicated by a dashed line, frame 90 includes an anchor 91 provided in an anchor area R, which is a sub-area of ​​the bottom surface 12 of the recessed section, and a support frame 92 connected to the anchor 91 and supporting the MEMS electrode 6. The support frame 92 includes an anchor connection frame 93 extending in the X direction from the anchor 91 and a base frame 94 arranged around the MEMS electrode 6.

[0065] Fig. Figure 7 is a cross-sectional view along the X-direction of anchor 91 along the in Fig. 3 shown line VII-VII. As in Fig. As illustrated in Figure 7, anchor 91 protrudes from the bottom surface 12 of the excavated section towards the Z1 side. In other words, anchor 91 is integrally formed with the bottom surface 12 of the excavated section in the anchor area R, which is a sub-area of ​​the bottom surface 12 of the excavated section. As shown in Fig. Indicated by a two-dot dashed line in Figure 1, the anchor region R is a region that, in plan view, encloses the center point O in the bottom surface 12 of the recessed section. More precisely, the center position in plan view of the anchor region R coincides with the center point O. A width dimension in the X-direction of the anchor region R is 2.5 µm or more and 25 µm or less, and is, for example, 10 µm in the present embodiment.

[0066] In the present embodiment, the anchors 91 are provided as a pair on both sides enclosing the connecting section 69 of the conductive path in the X direction between them, and include a first anchor 91a located on the X1 side of the connecting section 69 of the conductive path and a second anchor 91b located on the X2 side.

[0067] The anchor connection frame 93 is separated from the bottom surface 12 of the recessed section in the direction of the Z1 side and is not rigidly connected to any of the multiple wall surfaces 11 of the recessed section. As shown in Fig. As illustrated in Figure 1, the anchor connection frame 93 is formed integrally with the anchor 91 and includes a first connection frame 93a extending from the first anchor 91a to the X1 side, and a second connection frame 93b extending from the second anchor 91b to the X2 side.

[0068] The first connecting frame 93a extends to positions corresponding in the X-direction to the base section 76 of the first conductive path located in the first region S1 and to the base section 78 of the second conductive path located in the second region S2, and is connected to each of the base sections 76 and 78 of the first and second conductive paths via the insulating joint 9. The second connecting frame 93b, on the other hand, extends to positions corresponding in the X-direction to the base section 76 of the first conductive path located in the third region S3 and to the base section 78 of the second conductive path located in the fourth region S4, and is connected to each of the base sections 76 and 78 of the first and second conductive paths via the insulating joint 9.

[0069] The base frame 94 is separated from the bottom surface 12 of the recessed section in the direction of the Z1 side and is not connected to any of the first to fourth side surfaces 13 to 16 of the recessed section. The base frame 94 includes a first base frame 95, which is essentially U-shaped with an opening on the Y2 side, so that it surrounds the MEMS electrode 6 in a top view from the Y1 side, and a second base frame 96, which is essentially U-shaped with an opening on the Y1 side, so that it surrounds the MEMS electrode 6 from the Y2 side.

[0070] The first base frame 95 includes a first section 95a of the first frame, which is located on the Y1 side of the MEMS electrode 6 and extends in the X direction along the second side surface 14 of the recessed section over the first and third regions S1 and S3, a second section 95b of the first frame, which is located on the X1 side of the MEMS electrode 6 and extends in the Y direction along the first side surface 13 of the recessed section, and a third section 95c of the first frame, which is located on the X2 side of the MEMS electrode 6 and extends in the Y2 side or direction along the third side surface 15 of the recessed section.

[0071] Also referring to Fig. 2 The first section 95a of the first frame is connected via the insulating joint 9 to the base section 22 of the first fixed electrode and the base section 32 of the second fixed electrode. In the present embodiment, the insulating joints 9 are provided at one location in an X1-sided end section and at two locations in an X2-sided end section of the base section 22 of the first fixed electrode, and are provided at two locations in an X1-sided end section and at one location in an X2-sided end section of the base section 32 of the second fixed electrode.

[0072] The second section 95b of the first frame extends from an X1-side end section of the first section 95a of the first frame to the Y2 side and extends to just before a first flexible conductor 81, which will be described later. The second section 95b of the first frame is connected to the extension section 23 of the first fixed electrode via the insulating joint 9. In the present embodiment, the insulating joint 9 is provided at one location of a Y1-side end section and at two locations of a Y2-side end section of the extension section 23 of the first fixed electrode.

[0073] The third section 95c of the first frame extends from an end section on the X2 side of the first section 95a of the first frame to the Y2 side and extends to just before a fifth flexible conductor 85, which will be described later. The third section 95c of the first frame is connected to the extension section 33 of the second fixed electrode via the insulating joint 9. In the present embodiment, the insulating joint 9 is provided at one location of a Y1-side end section and at two locations of a Y2-side end section of the extension section 33 of the second fixed electrode.

[0074] It should be noted that, as in Fig. Figure 3 illustrates that the second section 95b of the first frame is electrically connected to the first connecting frame 93a via a fifth wiring layer 97 formed on the insulating film 18. Similarly, although not illustrated, the third section 95c of the first frame is electrically connected to the second connecting frame 93b via a wiring layer formed on the insulating film 18. Therefore, the first base frame 95 is electrically connected to either the first connecting frame 93a or the second connecting frame 93b and is set to the same potential as the armature connecting frame 93.

[0075] As in Fig. As illustrated in Figure 1, the second base frame 96 includes a first section 96a of the second frame, located on the Y2 side of the MEMS electrode 6 and extending in the X direction along the fourth side surface 16 of the recessed section over the second and fourth regions S2 and S4, a second section 96b of the second frame, located on the X1 side of the MEMS electrode 6 and extending in the Y direction along the first side surface 13 of the recessed section, and a third section 96c of the second frame, located on the X2 side of the MEMS electrode 6 and extending in the Y direction along the third side surface 15 of the recessed section.

[0076] Also referring to Fig. 2 The first section 96a of the second frame is connected via the insulating joint 9 to the base section 22 of the first fixed electrode and the base section 32 of the second fixed electrode. In the present embodiment, the insulating joints 9 are provided at two locations in an X1-sided end section and at one location in an X2-sided end section of the base section 22 of the first fixed electrode, and are provided at one location in an X1-sided end section and at two locations in an X2-sided end section of the base section 32 of the second fixed electrode.

[0077] The second section 96b of the second frame extends from an end section on the X1 side of the first section 96a of the second frame to the Y1 side and extends to just before a third flexible conductor 83, which will be described later. The second section 96b of the second frame is connected to the extension section 33 of the second fixed electrode via the insulating joint 9. In the present embodiment, the insulating joint 9 is provided at two locations of a Y1-side end section and at one location of a Y2-side end section of the extension section 33 of the second fixed electrode.

[0078] The third section 96c of the second frame extends from an end section on the X2 side of the first section 96a of the second frame to the Y1 side and extends to just before a seventh flexible conductor 87, which will be described later. The third section 96c of the second frame is connected to the extension section 23 of the first fixed electrode via the insulating joint 9. In the present embodiment, the insulating joint 9 is provided at two locations of a Y1-side end section and at one location of a Y2-side end section of the extension section 23 of the first fixed electrode.

[0079] It should be noted that, as in Fig. Figure 3 illustrates that the second section 96b of the second frame is electrically connected to the first connecting frame 93a via a sixth wiring layer 98 formed on the insulating film 18. Similarly, although not illustrated, the third section 96c of the second frame is electrically connected to the second connecting frame 93b via a wiring layer formed on the insulating film 18. Therefore, the second base frame 96 is electrically connected to either the first connecting frame 93a or the second connecting frame 93b and is set to the same potential as the armature connecting frame 93.

[0080] The following is a summary of how the MEMS electrode 6 is supported by the frame 90.

[0081] The movable electrode 8 has an X1-sided end section (the base sections 76 and 78 of the first and second conductive paths in the first and second regions S1 and S2) which is connected to the first connecting frame 93a via the insulating joining connection 9, and an X2-sided end section (the base sections 76 and 78 of the first and second conductive paths in the third and fourth regions S3 and S4) which is connected to the second connecting frame 93b via the insulating joining connection 9.

[0082] The fixed electrode 7 has an X1-sided end section (the extension sections 23 and 33 of the first and second fixed electrodes in the first and second regions S1 and S2) which is connected via the insulating joint 9 to the base sections 76 and 78 of the first and second conductive paths of the movable electrode 8, and an X2-sided end section (the extension sections 23 and 33 of the first and second fixed electrodes in the third and fourth regions S3 and S4) which is connected via the insulating joint 9 to the base sections 76 and 78 of the first and second conductive paths of the movable electrode 8. Furthermore, in the fixed electrode 7, the base sections 22 and 32 of the first and second fixed electrodes are connected via the insulating joint 9 to the first section 95a of the first frame or the first section 96a of the second frame.

[0083] Therefore, both the fixed electrode 7 and the movable electrode 8 are supported by the frame 90, are rigidly connected via the frame 90 to the anchor area R of the bottom surface 12 of the recessed section and are not rigidly connected to any of any further section of the bottom surface of the recessed section and any further of the wall surfaces 11 of the recessed section. (Configuration of the flexible line)

[0084] As in Fig. As illustrated in Figure 2, the sensor unit 3 in the first region S1 includes the first flexible conductor 81, which connects a Y2-sided end section of the extension section 23 of the first fixed electrode and the first side surface 13 of the recessed section in the X direction, and a second flexible conductor 82, which connects the base section 76 of the first conductive path and the first side surface 13 of the recessed section in the X direction. In the second region S2, the sensor unit 3 includes the third flexible conductor 83, which connects a Y1-sided end section of the extension section 33 of the second fixed electrode and the first side surface 13 of the recessed section in the X direction, and a fourth flexible conductor 84, which connects the base section 78 of the second conductive path and the first side surface 13 of the recessed section in the X direction.

[0085] In the third region S3, the sensor unit 3 includes the fifth flexible conductor 85, which connects a Y2-sided end section of the extension section 33 of the second fixed electrode and the third side surface 15 of the recessed section in the X direction, and a sixth flexible conductor 86, which connects the base section 76 of the first conductive path and the third side surface 15 of the recessed section in the X direction. In the fourth region S4, the sensor unit 3 includes the seventh flexible conductor 87, which connects a Y1-sided end section of the extension section 23 of the first fixed electrode and the third side surface 15 of the recessed section in the X direction, and an eighth flexible conductor 88, which connects the base section 78 of the second conductive path and the third side surface 15 of the recessed section in the X direction.

[0086] Furthermore, the sensor unit 3 includes a ninth flexible conductor 89a, which connects in the X direction the first connecting frame 93a and the first side surface 13 of the recessed section between the second flexible conductor 82 and the fourth flexible conductor 84. The sensor unit 3 also includes a tenth flexible conductor 89b, which connects in the X direction the second connecting frame 93b and the third side surface 15 of the recessed section between the sixth flexible conductor 86 and the eighth flexible conductor 88. The ninth and tenth flexible conductors 89a and 89b are provided as a pair across the Y-direction center line O2.

[0087] That is, the first to fourth and the ninth flexible leads 81 to 84 and 89a are located on the X1 side of the MEMS electrode 6, and the fifth to eighth and the tenth flexible leads 85 to 88 and 89b are located on the X2 side of the MEMS electrode 6.

[0088] Each of the first to ten flexible leads 81 to 89b (hereinafter referred to collectively as flexible lead 80 in some cases) is made of conductive silicon and has sections bent by 180° at a multitude of locations, such that one section is moved back and forth several times in the X direction and another section is moved back and forth several times in the Y direction. It is configured to be stretchable in the X and Y directions by bending and deforming it with these bent sections as a starting point. The flexible lead 80 merely provides an electrical connection from the outside of the recessed section 10 to the sensor unit 3 and does not rigidly connect the sensor unit 3 to the wall surface 11 of the recessed section. The flexible lead 80 is electrically connected to the electrode pad 4 via wiring (not illustrated). (Circuit configuration of the MEMS electrode)

[0089] Fig. Figure 8A is a simplified element diagram illustrating a simplified circuit configuration of the MEMS electrode 6. As shown in Fig. As illustrated in Figure 8A, a first capacitor C1a and a second capacitor C2a are configured in the first region S1, a third capacitor C3a and a fourth capacitor C4a are configured in the second region S2, a third capacitor C3b and a fourth capacitor C4b are configured in the third region S3, and a first capacitor C1b and a second capacitor C2b are configured in the fourth region S4. In the present embodiment, in each of the capacitors C1 to C4, the distances between the electrodes are set such that they are equal in a reference state in which no acceleration is acting, and thus the capacitances are equal.

[0090] It should be noted that in Fig. 8A, to distinguish between the first and second capacitors C1 and C2, which are located in the first and fourth sections S1 and S4 respectively, the first and second capacitors located in the first section S1 are designated C1a and C2a, and the first and second capacitors located in the fourth section S4 are designated C1b and C2b. Similarly, in Fig. 8A, to distinguish between the third and fourth capacitors C3 and C4, which are located in the second and third areas S2 and S3, the third and fourth capacitors located in the second area S2 are designated C3a and C4a, and the third and fourth capacitors located in the third area S3 are designated C3b and C4b.

[0091] In the present embodiment, the acceleration is detected on the basis of the first output voltage Vp output by the first and seventh flexible lines 81 and 87 and the second output voltage Vn output by the third and fifth flexible lines 83 and 85, when the first input voltage drvn, which is an alternating voltage, is applied to the base section 76 of the first conductive path via the second and sixth flexible lines 82 and 86, and the second input voltage drvp, which is an alternating voltage, is applied to the base section 78 of the second conductive path via the fourth and eighth flexible lines 84 and 88.

[0092] In a case where the movable electrode 8 is removed from the in Fig. In the state illustrated in Figure 8A, when the fixed electrode 7 is shifted towards the X2 side, the capacitance in the first and fourth capacitors C1 and C4 increases with a change in the distance between the fixed electrode 7 and the movable electrode 8, while the capacitance in the second and third capacitors C2 and C3 decreases. Conversely, in a case where the movable electrode 8 is moved from the X2 side, the capacitance decreases. Fig. 8A illustrates the state with respect to the fixed electrode 7 being shifted to the X1 side, increasing the capacitance in the first and fourth capacitors C1 and C4, while increasing the capacitance in the second and third capacitors C2 and C3.

[0093] Fig. 8B is a corresponding circuit diagram that shows each element of Fig. 8A illustrates. Fig. 8C illustrates this in Fig. Figure 8B illustrated the corresponding circuit diagram in a further simplified manner. As in Fig. Figure 8C illustrates that when the first input voltage drvn and the second input voltage drvp, which is symmetrical to the first input voltage drvn, are applied to the MEMS electrode 6, the first output voltage Vp and the second output voltage Vn, which is symmetrical to the first output voltage Vp, are output along with a change in the capacitance of the first to fourth capacitors C1 to C4. At this point, the first output Vp and the second output Vn may similarly contain common-mode noise and the like.

[0094] Next, by calculating the difference between the first output voltage Vp and the second output voltage Vn, an output can be obtained in which common-mode interference and the like are suppressed. Since the MEMS electrode 6 encloses a test mass, individual interferences caused by individual variations in the test mass can be present in both the first output voltage Vp and the second output voltage Vn. Therefore, by calculating the difference between the first output voltage Vp and the second output voltage Vn, it is possible to obtain an output in which not only common-mode interference and the like, but also individual interferences are suppressed. Thus, the accuracy of the acceleration calculation can be improved by calculating the acceleration based on the output.

[0095] According to the accelerometer 1 according to the above embodiment, the following effects are observed.

[0096] (1) The accelerometer 1 includes the device-side substrate 2 with the first main surface 2a and the second main surface 2b facing the first main surface 2a, the recessed section 10 which extends from the first main surface 2a towards the second main surface 2b, the MEMS electrode 6 provided in the recessed section 10 which includes the fixed electrode 7 with the first fixed electrode 20 and the second fixed electrode 30, which is electrically insulated from the first fixed electrode 20, and the movable electrode 8 with the first movable electrode 40 and the second movable electrode 50, which is electrically insulated from the first movable electrode 40, forming a differential circuit, and the insulating joint 9.which mechanically connects the first movable electrode 40 and the second movable electrode 50 and simultaneously electrically insulates the first movable electrode 40 and the second movable electrode 50.

[0097] Consequently, since the first movable electrode 40 and the second movable electrode 50 are mechanically connected and simultaneously electrically insulated via the insulating joint 9, two movable electrodes with different potentials can be enclosed in a test mass that is displaced as a single unit. As a result, individual deviations occur simultaneously at the first movable electrode 40 and the second movable electrode 50. By achieving a difference between the two obtained output voltages, outputs are obtained in which individual deviations cancel each other out, in addition to eliminating common-mode interference and the like. Therefore, the accuracy of the acceleration calculation can be improved based on an output in which common-mode interference and the like, as well as individual deviations, are suppressed.

[0098] (2) The first fixed electrode 20 includes a plurality of the first fixed electrode elements 21, the second fixed electrode 30 includes a plurality of the second fixed electrode elements 31, the first movable electrode 40 includes a plurality of the first movable electrode elements 41, and the second movable electrode 50 includes a plurality of the second movable electrode elements 51. The MEMS electrode 6 includes the first capacitor C1, which includes a plurality of the first fixed electrode elements 21 and a plurality of the first movable electrode elements 41 facing each of the first fixed electrode elements 21 in the X direction, the second capacitor C2, which includes a plurality of the first fixed electrode elements 21 and a plurality of the second movable electrode elements 51 facing each of the first fixed electrode elements 21 in the X direction, and the third capacitor C3.which includes a plurality of the second fixed electrode elements 31 and a plurality of the first movable electrode elements 41, which are oriented in the X-direction towards each of the second fixed electrode elements 31, and the fourth capacitor C4, which includes a plurality of the second fixed electrode elements 31 and a plurality of the second movable electrode elements 51, which are oriented in the X-direction towards each of the second fixed electrode elements 31. When the first movable electrode 40 and the second movable electrode 50 are displaced in the X-direction in a state in which the input voltages drvn and drvp are applied to the first movable electrode 40 and the second movable electrode 50 with opposite phases, the output voltages Vp and Vn with opposite phases are output from the first fixed electrode 20 and the second fixed electrode 30.

[0099] This means that the above effect manifests itself appropriately in a fully differential acceleration sensor.

[0100] (3) In a top view, the MEMS electrode 6 encloses the first capacitor C1 and the second capacitor C2 in the first region S1 on the Y1 side and encloses the third capacitor C3 and the fourth capacitor C4 in the second region S2 on the Y2 side. In the first region S1, the first movable electrode element 41 and the second movable electrode element 51, arranged next to the X1 side of the first movable electrode element 41, are connected to each other via the insulating joint 9, and these form the first set of movable electrode elements 8A. Each plurality of the first set of movable electrode elements 8A and each plurality of the first fixed electrode elements 21 are arranged alternately in the X direction.In the second region S2, the first movable electrode element 41 and the second movable electrode element 51, arranged next to the X2 side of the first movable electrode element 41, are connected to each other via the insulating joint 9, and these form the movable electrode element 8B of the second set. Each plurality of the movable electrode elements 8B of the second set and each plurality of the second fixed electrode elements 31 are arranged alternately in the X direction.

[0101] As a result, when the movable electrode 8 is displaced in the X direction, the increase and decrease of the capacitance in the first capacitor C1 and in the third capacitor C3 and the increase and decrease of the capacitance in the second capacitor C2 and in the fourth capacitor C4 are symmetrical, so that a fully differential MEMS accelerometer can be formed by the first to fourth capacitors C1 to C4.

[0102] (4) The movable electrode 8 further includes the conductive path section 60, which extends in the X direction between a plurality of the movable electrode elements of the first set 8A and a plurality of the movable electrode elements 8B of the second set.

[0103] As a result, the conductive path section 60 can be compactly arranged between the movable electrode element 8A of the first set and the movable electrode elements 8B of the second set.

[0104] (5) The conductive path section 60 includes the first conductive path section 61, which is mechanically connected to a plurality of the movable electrode elements 8A of the first set, and the second conductive path section 65, which is mechanically connected to a plurality of the movable electrode elements 8B of the second set.

[0105] As a result, the first conductive path section 61, which is electrically connected to the movable electrode element 8A of the first set, and the second conductive path section 65, which is electrically connected to the movable electrode element 8B of the second set, are individually configured in the conductive path section 60, so that the circuit connection of the conductive path section 60 can be simplified.

[0106] (6) The first conductive path section 61 includes the first section 62 of the first conductive path, which is electrically connected to the first movable electrode element 41, and the second section 63 of the first conductive path, which is electrically connected to the second movable electrode element 51. The second conductive path section 65 includes the first section 66 of the second conductive path, which is electrically connected to the first movable electrode element 41, and the second section 67 of the second conductive path, which is electrically connected to the second movable electrode element 51. The first section 62 of the first conductive path and the first section 66 of the second conductive path are electrically connected, and the second section 63 of the first conductive path and the second section 67 of the second conductive path are electrically connected.

[0107] As a result, the first movable electrode elements 41, which are located in different areas (for example, the first area S1 and the second area S2), can be electrically connected to each other via the first conductive path section 61 and the second conductive path section 65, and the second movable electrode elements 51, which are located in different areas (for example, the first area S1 and the second area S2), can be electrically connected to each other via the first conductive path section 61 and the second conductive path section 65, so that the circuit connection of the conductive path section 60 can be simplified.

[0108] (7) The first section 62 of the first conductive path and the second section 63 of the first conductive path are connected via the insulating joint 9. The first section 66 of the second conductive path and the second section 67 of the second conductive path are connected via the insulating joint 9.

[0109] As a result, the first section 62 of the first conductive path and the second section 63 of the first conductive path can be configured as one test ground, and the first section 66 of the second conductive path and the second section 67 of the second conductive path can be configured as a single ground.

[0110] (8) The first conductive path section 61 and the second conductive path section 65 are connected via the insulating joint 9.

[0111] As a result, the first conductive path section 61 and the second conductive path section 65 can be configured as a single test mass.

[0112] (9) The first section 62 of the first conductive path and the first section 66 of the second conductive path are electrically connected via the first wiring layer 64 of the connecting section. The second section 63 of the first conductive path and the second section 67 of the second conductive path are electrically connected via the second wiring layer 68 of the connecting section.

[0113] As a result, while the first conductive path section 61 and the second conductive path section 65 are configured as a single test mass, the first movable electrode elements 41 enclosed in each region can be electrically connected to each other while maintaining insulation with respect to the second movable electrode element 51, and the second movable electrode elements 51 enclosed in each region can be electrically connected to each other while maintaining insulation with respect to the first movable electrode element 41.

[0114] (10) The first conductive path section 61 includes the first and third spring sections 71 and 73, which are elastically deformed at both end sections in the X-direction. The second conductive path section 65 includes the second and fourth spring sections 72 and 74, which are elastically deformed at both end sections in the X-direction.

[0115] Consequently, a pair of spring sections 71 to 74 is provided in the Y-direction on each side of the conductive path section 60 in the X-direction. Therefore, the first movable electrode element 8A and the second movable electrode element 8B can be elastically and stably supported by a pair of common spring sections 71 to 74, which are provided in the Y-direction on each side of the conductive path section 60 in the X-direction. Therefore, the structure can be simplified compared to a case in which a pair of spring sections is provided individually in the Y-direction for each of the movable electrode elements 8A of the first set and 8B of the second set.

[0116] (11) In the recessed section 10, the third area S3 is further included in plan view next to the first area S1 in the X direction, and the fourth area S4 is included next to the second area S2 in the X direction and next to the third area S3 in the Y direction, and the first and second capacitors C1 and C2 are also located in the fourth area S4 in addition to the first area S1, and the third and fourth capacitors C3 and C4 are located in the third area S3 in addition to the second area S2.

[0117] Consequently, the first to fourth capacitors, C1 to C4, are arranged diagonally in the recessed section 10. As a result, since deviations of a pair of diagonally arranged capacitors occur in opposite directions, the disturbances caused by the fluctuations are suppressed by canceling each other out.

[0118] (12) The accelerometer 1 includes the device-side substrate 2 with the first main surface 2a and the second main surface 2b facing the first main surface 2a, the recessed section 10 which extends from the first main surface 2a towards the second main surface 2b and is defined by a plurality of the wall surfaces 11 of the recessed section, the anchor 91 which projects from the anchor area R which is a sub-area of ​​any plurality of the wall surfaces 11 of the recessed section, the support frame 92, one end section of which is connected to the anchor 91 and extends into the recessed section 10 and is separated from a plurality of the wall surfaces 11 of the recessed section, the MEMS electrode 6 which is located in the recessed section 10, and the insulating joint 9.which mechanically connects the MEMS electrode 6 to the support frame 92 and simultaneously electrically insulates the MEMS electrode 6 from the support frame 92.

[0119] In this scenario, an accelerometer is generally mounted on a printed circuit board or similar substrate in a housing and is used by being installed in various devices. Housing stresses can arise when the housing is mounted on a printed circuit board or similar substrate and / or when the housing is installed / used in a device. Consequently, when the housing stress is transferred to the accelerometer, distortion occurs in the accelerometer, and a characteristic of the accelerometer may change. That is, there is a problem in providing an accelerometer where distortion due to housing stresses can be suppressed.

[0120] On the other hand, since in the accelerometer 1 the support frame 92 is supported by the armature 91 with respect to the armature area R, any housing stress (distortion) that may occur in the device-side substrate 2 is transmitted via the armature 91 and the support frame 92 to the MEMS electrode 6 supported by the support frame 92. Consequently, compared to a case where housing stresses are transmitted from a multitude of locations, if the MEMS electrode 6 is supported at a multitude of locations with respect to the wall surface 11 of the recessed section, any distortion that may occur in the MEMS electrode 6 can be easily minimized. Therefore, it is easy to stabilize the detection by the accelerometer 1.

[0121] (13) The anchor area R is located on the bottom surface 12 of the excavated section.

[0122] As a result, it is easy to support the support frame 92 in a balanced manner by the anchor 91 provided on the bottom surface 12 of the recessed section, compared to a case where the anchor 91 is provided on one of the first to fourth side surfaces 13 to 16 of the recessed section.

[0123] (14) The anchor area R has a width dimension in the X direction of 2.5 µm or more and 25 µm or less.

[0124] As a result, stresses transmitted from the device-side substrate 2 via the armature 91 to the support frame 92 can be easily reduced. In cases where the width dimension R of the armature area in the X-direction is less than 2.5 µm, it is difficult to ensure the support stiffness of the support frame 92 by the armature 91. On the other hand, if the width dimension R of the armature area in the X-direction exceeds 25 µm, the stress transmitted from a device-side substrate via the armature 91 to the support frame 92 tends to be large, the MEMS electrode 6 tends to be distorted in a complex manner, and therefore disturbances in the measurement by the accelerometer 1 tend to increase.

[0125] (15) The anchor area R encloses the center point O in plan view of the bottom surface of the sunken section.

[0126] As a result, the support frame 92 can be more easily and evenly supported by the armature 91, and stresses that may arise due to the support in the MEMS electrode 6 can be easily suppressed.

[0127] (16) The center point of anchor 91 coincides in plan view with the center point O of the bottom surface of the sunken section.

[0128] As a result, the support frame 92 can be more easily supported by the armature 91 in a more balanced manner, and stresses that may arise due to the support in the MEMS electrode 6 can be more easily suppressed.

[0129] (17) The support frame 92 includes the anchor connection frame 93, which extends from the anchor 91 towards the wall surface 11 of the recessed section, and the base frame 94, which is rigidly connected directly or indirectly to the anchor connection frame 93 and extends along a plurality of the wall surfaces 11 of the recessed section around the MEMS electrode 6.

[0130] Consequently, while the anchor 91 is provided in the anchor area R of the bottom surface 12 of the recessed section, the base frame 94 can easily be configured to be separated from the anchor 91 by the anchor connection frame 93 and to extend along the wall surface 11 of the recessed section. The foregoing makes it easy to ensure ample space within the base frame 94 for the MEMS electrode 6.

[0131] (18) The MEMS electrode 6 is supported by the base frame 94.

[0132] As a result, the MEMS electrode 6 arranged inside the base frame 94 can be appropriately supported by the base frame.

[0133] (19) The anchor 91 includes the first anchor 91a and a second anchor 91b separate from the first anchor 91a.

[0134] As a result, anchor 91 can be configured separately as first anchor 91a and second anchor 91b, and design freedom in construction can be improved.

[0135] (20) The movable electrode 8 further includes the conductive path section 60, which is connected to a plurality of the first and second movable electrode elements 41 and 51, and the conductive path section 60 has a section between the first armature 91a and the second armature 91b which extends in the Y direction which intersects the X direction in which the first armature 91a and the second armature 91b are arranged.

[0136] As a result, the connecting section 69 of the conductive path, which connects the first conductive path section 61 and the second conductive path section 65, can be arranged compactly using a space between the first anchor 91a and the second anchor 91b.

[0137] (21) The fixed electrode 7 and the movable electrode 8 are connected to the wall surface 11 of the recessed section via a flexible conductor 80 which is conductive and elastically deformable.

[0138] Consequently, while the MEMS electrode 6, supported by the frame 92, is electrically connected to the device-side substrate 2 via the flexible cable 80, the transmission of voltage / distortion from the device-side substrate 2 to the MEMS electrode 6 is suppressed. Since any distortion that may occur in the MEMS electrode 6 is suppressed, the detection accuracy of the accelerometer can therefore be easily stabilized. [Second embodiment]

[0139] Fig. Figure 9 is an enlarged top view similar to Fig. 2, illustrating a sensor unit 103 of an accelerometer 100 according to a second embodiment of the present disclosure. As in Fig. As illustrated in Figure 9, the sensor unit 103 differs from the sensor unit 3 of the first embodiment with respect to a configuration of a conductive path section 160 and a frame 190. Components common to the sensor unit 3 are designated with the same reference numerals, and their explanation is omitted.

[0140] The frame 190 differs from the frame 90 of the first embodiment in that it does not include the armature 91 and the armature connection frame 93, but instead inserts a pair of connection sections 110 from wall surfaces of the recessed section, which connects a MEMS electrode 106 to each of the first and third side surfaces 13 and 15 of the recessed section.

[0141] A pair of connecting sections 110 of wall surfaces of the recessed section is located between the base section 76 of the first conductive path and the base section 78 of the second conductive path on both sides of the X1 side and the X2 side of the MEMS electrode 106 and is connected to them via the insulating joint 9. Furthermore, each of the connecting sections 110 of wall surfaces of the recessed section is connected to the first side surface 13 of the recessed section or the third side surface 15 of the recessed section.

[0142] Fig. Figure 10 is an enlarged view of the conductive path segment 160 around the X1 side. As in Fig. As illustrated in Figure 10, since the anchor 91 and the anchor connection frame 93 are not provided, a first conductive path section 161 and a second conductive path section 165 are directly connected in the Y direction via the insulating joint 9, and the ninth and tenth flexible conductors 89a and 89b are not provided. The conductive path section 160 forms an I-shaped test mass extending in the X direction in six rows.

[0143] Fig. Figure 11 is a cross-sectional view along the first movable electrode element 41 in the first region S1 (of the second movable electrode element 51 in the second region S2) along the in Fig. Line XI-XI shown in 10. As in Fig. As illustrated in Figure 11, in the first region S1 the first movable electrode element 41 is electrically connected via the first wiring layer 42 to a first section 162 of a first conductive path, and in the second region S2 the second movable electrode element 51 is electrically connected via the fourth wiring layer 54 to a second section 167 of a second conductive path.

[0144] Fig. Figure 12 is a cross-sectional view along the second movable electrode element 51 in the first region S1 (of the first movable electrode element 41 in the second region S2) along the in Fig. Line XII-XII shown in 10. As in Fig. As illustrated in Figure 12, the second movable electrode element 51 in the first region S1 is electrically connected to a second section 163 of the first conductive path via the second wiring layer 52, and in the second region S2 the first movable electrode element 41 is electrically connected to a first section 166 of the second conductive path via the third wiring layer 44.

[0145] Fig. Figure 14 is an enlarged view of the conductive path segment 160 around the X2 side. As shown in the Fig. 10 and Fig. As illustrated in Figure 14, the conductive path section 160 includes a seventh wiring layer 164, which electrically connects the first section 162 of the first conductive path and the first section 166 of the second conductive path, and an eighth wiring layer 168, which electrically connects the second section 163 of the first conductive path and the second section 167 of the second conductive path. The seventh wiring layer 164 is provided at an end section on the X1 side of the conductive path section 160, specifically at a position corresponding to the extension sections 23 and 33 of the first and second fixed electrodes in the X direction. The eighth wiring layer 168 is provided at an end section on the X2 side of the conductive path section 160, more precisely at a position corresponding to the extension sections 23 and 33 of the first and second fixed electrodes in the X direction.

[0146] Fig. Figure 13 is a cross-sectional view along the seventh wiring layer 164 along the in Fig. Line XIII-XIII shown in 10. As in Fig. As illustrated in Figure 13, the seventh wiring layer 164 is formed on the insulating film 18, which is laminated onto a surface on the Z1 side of the conductive path section 160, and electrically connects the first section 162 of the first conductive path and the first section 166 of the second conductive path via a contact that penetrates the insulating film 18 in the Z direction.

[0147] Fig. 15 is a cross-sectional view along the eighth wiring layer 168 along the in Fig. Line XV-XV shown in 14. As in Fig. As illustrated in Figure 15, the eighth wiring layer 168 is formed on the insulating film 18, which is laminated onto a surface on the Z1 side of the conductive path section 160, and electrically connects the second section 163 of the first conductive path and the second section 167 of the second conductive path via a contact that penetrates the insulating film 18 in the Z direction.

[0148] Also in the present embodiment, the first movable electrode element 41 and the second movable electrode element 51, while connected via the insulating joint 9 to a single test ground formed by the conductive path section 160, are electrically connected to the corresponding conductive path section 160, while the insulation is maintained via the first wiring layer 42, the second wiring layer 52, the third wiring layer 44, and the fourth wiring layer 54. Therefore, a fully differential accelerometer can be configured by the sensor unit 103, and, as in the first embodiment, an output can be obtained in which both common-mode and individual interferences are suppressed, thus improving the accuracy of the acceleration calculation based on the output. [Third embodiment (reference)]

[0149] Fig. Figure 16 is an enlarged top view similar to Fig. 2, illustrating a sensor unit 203 of an accelerometer 200 according to a third embodiment of the present disclosure. As in Fig. As illustrated in Figure 16, the sensor unit 203 differs from the sensor unit 3 of the first embodiment with respect to a configuration of a conductive path section 260 (see Figure 16). Fig. 17) and a frame 290. Furthermore, sensor unit 203 differs from sensor unit 3 in that the first and second capacitors C1 and C2 are provided together in each of the first to fourth sections S1 to S4, and the third and fourth capacitors C3 and C4 are not provided. Components common to sensor unit 3 are designated with the same reference numerals and are omitted from the explanation.

[0150] First, a configuration of the frame 290 is described. The frame 290 differs from the frame 90 according to the first embodiment with respect to a configuration of an anchor 291 and an anchor connection frame 293. In particular, the anchors 291 are provided as a pair in the Y-direction across the conductive path section 260 in an anchor area R1 long in the X-direction, which is located in the middle of the bottom surface 12 of the recessed section, and include a first anchor 291a located on the Y1 side and a second anchor 291b located on the Y2 side.

[0151] The anchor connection frame 293 includes a first connection frame 293a, which is connected to the first anchor 291a, and a second connection frame 293b, which is connected to the second anchor 291b. The first connection frame 293a extends from the first anchor 291a towards the Y1 side and is connected to a section 95a of the first frame section that is central in the X direction. The second connection frame 293b extends from the second anchor 291b towards the Y2 side and is connected to the first section 96a of the second frame.

[0152] In the frame 290, the armature 291, the armature connection frame 293 and the base frame 94 are formed in one piece by machining the device-side substrate 2 made of conductive silicon using a MEMS technique. Fig. Figure 17 is an enlarged top view illustrating an edge of the first area S1 of the sensor unit 203. Fig. Figure 18 is a cross-sectional view parallel to the X-direction, passing through the first anchor 291a and along the in Fig. Line XVIII-XVIII shown in 17 is taken. As in Fig. As illustrated in Figure 18, the first anchor 291a protrudes from the ground surface 12 of the sunken section towards the Z1 side, while the first connecting frame 293a is separated from the ground surface 12 of the sunken section towards the Z1 side.

[0153] Next, a configuration of a MEMS electrode 206 will be described with reference to the Fig. 16 and Fig. 17 described. In the present embodiment, the arrangement of the first and second movable electrode elements 41 and 51 is the same in all regions S1 to S4, from the first to the fourth, and the first and second fixed electrode elements 21 and 31 are the same as those in the first and second embodiments. In particular, in all regions S1 to S4, from the first to the fourth, the first movable electrode element 8A of the first set is formed by the first movable electrode element 41 and the second movable electrode element 51 located next to the X1 side of the first movable electrode element 41.

[0154] This means that in the first and fourth regions S1 and S4, the movable electrode element 8A of the first set and the first fixed electrode element 21 are arranged alternately such that they face each other in the X-direction. In the first and fourth regions S1 and S4, the first fixed electrode element 21 and the first movable electrode element 41 located on the X1 side of the first fixed electrode element 21 form the first capacitor C1, and the first fixed electrode element 21 and the second movable electrode element 51 located on the X2 side of the first fixed electrode element 21 form the second capacitor C2.

[0155] On the other hand, in the second and third regions S2 and S3, the movable electrode element 8A of the first set and the second fixed electrode element 31 are arranged alternately such that they face each other in the X direction. In the second and third regions S2 and S3, the second fixed electrode element 31 and the first movable electrode element 41 located on the X1 side of the second fixed electrode element 31 form the third capacitor C3, and the second fixed electrode element 31 and the second movable electrode element 51 located on the X2 side of the second fixed electrode element 31 form the fourth capacitor C4.

[0156] The conductive path section 260 includes a first conductive path section 261, located on the Y1 side, and a second conductive path section 265, located on the Y2 side. In the first conductive path section 261, the Y2-side end sections of the movable electrode element 8A of the first set, located in the first and third regions S1 and S3, are connected via the insulating joint 9. In the second conductive path section 265, the Y1-side end sections of the movable electrode element 8A of the first set, located in the second and fourth regions S2 and S4, are connected via the insulating joint 9.

[0157] Each of the first and second conductive path sections 261 and 265 is configured in a conductor-like manner such that a section extending in two rows in the X-direction and a section extending in the Y-direction of each of the first and second movable electrode elements 41 and 51 intersect. In the first conductive path section 261, only a first section 262 of the first conductive path is formed. In the second conductive path section 265, only a second section 267 of the second conductive path is formed.

[0158] Fig. Figure 19 is a cross-sectional view along the first movable electrode element 41 along the in Fig. Line XIX-XIX shown in 17. As in Fig. As illustrated in Figure 19, the first movable electrode elements 41, which are located on the Y1 side and the Y2 side with respect to the conductive path section 260, are all electrically connected to the first section 262 of the first conductive path via a first wiring layer 242.

[0159] Fig. Figure 20 is a cross-sectional view along the second movable electrode element 51 along the in Fig. Line XX-XX shown in 17. As in Fig. As illustrated in Figure 20, the second movable electrode elements 51, which are located on the Y1 side and the Y2 side with respect to the conductive path section 260, are all electrically connected to the second section 267 of the second conductive path via a second wiring layer 252.

[0160] Both the first and second wiring layers 242 and 252 are formed on the insulating film 18, which is laminated onto a Z1-side surface of the conductive path section 260, and are electrically connected via a contact penetrating the insulating film 18 to the first and second movable electrode elements 41 and 51, the first conductive path section 261, and the second conductive path section 265. The first and second wiring layers 242 and 252 are made of conductive metal, for example, aluminum.

[0161] Also according to the present embodiment, since the MEMS electrode 6 includes the conductive path section 260, which is configured as a single test ground, individual disturbances caused by individual deviations can be collectively contained in the output voltage, which is output based on a change in the capacitance of the first to fourth capacitors C1 to C4. Furthermore, since the MEMS electrode 206 is supported by the frame 290 through the armature area R1 of the bottom surface 12 of the recessed section, hardly any case stresses are transferred to the MEMS electrodes 206. [Fourth embodiment (reference)]

[0162] Fig. 21 is an enlarged top view similar to Fig. 2, illustrating a sensor unit 303 of an accelerometer 300 according to a fourth embodiment of the present disclosure. As in Fig. As illustrated in Figure 21, in the sensor unit 303 a MEMS electrode 306 is supported by a frame 390 from an anchor area R2 which is located in the middle of the bottom surface 12 of the recessed section.

[0163] Frame 390 includes an anchor 391 located in anchor area R2, an anchor connection frame 393 extending from anchor 391 to the X2 side, and a base frame 394 extending along the wall surface 11 of the recessed section and connected to the anchor connection frame 393. Frame 390 differs from frame 90 according to the first embodiment and frame 290 according to the third embodiment in that the anchor connection frame 393 is not configured as a pair but as a single frame. In frame 390, the anchor connection frame 393 and the base frame 394 are separated from the bottom surface 12 of the recessed section in the direction of the Z1 side and are not connected to any of the other wall surfaces 11 of the recessed section.

[0164] The MEMS electrode 306 includes a first fixed electrode 320 and a first movable electrode 340 located on the Y1 side, and a second fixed electrode 330 and a second movable electrode 350 located on the Y2 side. A plurality of first fixed electrode elements 321 of the first fixed electrode 320 and a plurality of first movable electrode elements 341 of the first movable electrode 340 are arranged so that they face each other in the Y direction. Similarly, a plurality of second fixed electrode elements 331 of the second fixed electrode 330 and a plurality of second movable electrode elements 351 of the second movable electrode 350 are arranged so that they face each other in the Y direction.

[0165] The first and second fixed electrodes 320 and 330 and the first and second movable electrodes 340 and 350 are connected to the base frame 394 via the insulating joint 9. Furthermore, in the present embodiment, since the MEMS electrode 306 is supported by the frame 390 through the anchor area R2 of the bottom surface 12 of the recessed section, hardly any housing stresses are transferred to the MEMS electrodes 306. [Fifth embodiment (reference)]

[0166] Fig. 22 is an enlarged top view similar to Fig. 2, illustrating a sensor unit 403 of an accelerometer 400 according to a fifth embodiment of the present disclosure. As in Fig. As illustrated in Figure 22, in the sensor unit 403 four MEMS electrodes 406 are supported by a frame 490 from an anchor area R3 located in the middle of the bottom surface 12 of the recessed section.

[0167] Frame 490 includes an anchor 491 located in anchor area R3, an anchor connection frame 493 extending from anchor 491 on both sides in the x-direction and both sides in the y-direction, and a base frame 494 extending along the wall surface 11 of the recessed section and connected to the anchor connection frame 493. Frame 490 differs from frame 90 of the first embodiment and frame 290 of the third embodiment in that the anchor connection frames 493 are configured as a pair in both the x-direction and the y-direction. In frame 490, the anchor connection frame 493 and the base frame 494 are separated from the bottom surface 12 of the recessed section in the direction of the Z1 side and are not connected to any of the other wall surfaces 11 of the recessed section.

[0168] The anchor connection frame 493 includes a first connection frame 493a extending from anchor 491 to the X1 side, a second connection frame 493b extending from anchor 491 to the X2 side, a third connection frame 493c extending from anchor 491 to the Y1 side, and a fourth connection frame 493d extending from anchor 491 to the Y2 side. Each of the first to fourth connection frames 493a to 493d is connected to each side of the base frame 494. Therefore, within the frame 490, the first to fourth enclosed spaces Q1 to Q4 are formed, each with a rectangular shape in plan view, with the first space designated S1, the second space S2, the third space S3, and the fourth space S4, respectively.

[0169] A MEMS electrode 406a for detecting acceleration in the Y direction is arranged in the first and fourth enclosed spaces Q1 and Q4, which are diagonally above the center point O, and a MEMS electrode 406b for detecting acceleration in the X direction is arranged in the second and third enclosed spaces Q2 and Q3. Each of the MEMS electrodes 406 is connected to the armature connection frame 493 and / or the base frame 494 via the insulating connection 9.

[0170] According to the present embodiment, since four of the MEMS electrodes 406 are carried via one of the frame 490 through the anchor area R3 of the bottom surface 12 of the recessed section, hardly any case stresses are transferred to the MEMS electrodes 406.

[0171] It should be noted that the present disclosure is not limited to the configuration described in the embodiment above and various modifications are possible.

[0172] [Additional Note] An accelerometer according to the present disclosure offers one of the following aspects. [First aspect]

[0173] Accelerometer, which includes the following: a substrate with a first main surface and a second main surface opposite or facing the first main surface; a recessed section that extends from the first main surface towards the second main surface; a MEMS electrode provided in the recessed section, and the MEMS electrode includes a fixed electrode with a first fixed electrode and a second fixed electrode electrically isolated from the first fixed electrode, and a movable electrode with a first movable electrode and a second movable electrode electrically isolated from the first movable electrode, forming a differential circuit; and an insulating joining connection that mechanically connects the first movable electrode and the second movable electrode and simultaneously electrically insulates the first movable electrode and the second movable electrode from each other. [Second aspect]

[0174] Accelerometer according to the first aspect, where the first solid electrode includes a multitude of first solid electrode elements, the second solid electrode includes a multitude of second solid electrode elements, the first movable electrode includes a multitude of first movable electrode elements, the second movable electrode includes a plurality of second movable electrode elements, The MEMS electrode includes the following: a first capacitor comprising the plurality of first fixed electrode elements and the plurality of first movable electrode elements facing each of the plurality of first fixed electrode elements in a first direction; a second capacitor comprising the plurality of first fixed electrode elements and the plurality of second movable electrode elements facing each of the plurality of first fixed electrode elements in the first direction; a third capacitor comprising the plurality of second fixed electrode elements and the plurality of first movable electrode elements facing each of the plurality of second fixed electrode elements in the first direction; and a fourth capacitor, which includes the plurality of second fixed electrode elements and the plurality of second movable electrode elements, which are oriented towards each of the plurality of second fixed electrode elements in the first direction, and When the first movable electrode and the second movable electrode are shifted in the first direction in a state in which input voltages of opposite phases are applied to the first movable electrode and the second movable electrode, output voltages of opposite phases are output from the first fixed electrode and the second fixed electrode. [Third aspect]

[0175] Accelerometer according to the second aspect, where The MEMS electrode, shown in top view, includes the following: the first capacitor and the second capacitor in a first region located on one side in a second direction orthogonal to the first direction; and the third capacitor and the fourth capacitor in a second region located on the other side in the second direction, wherein in the first region the first movable electrode element and the second movable electrode element, which is arranged next to one side in the first direction of the first movable electrode element, are connected to each other via the insulating joining connection, and these form a movable electrode element of a first set, and each of a plurality of the movable electrode elements of the first set and each of the plurality of first fixed electrode elements are arranged alternately in the first direction, and wherein in the second region the first movable electrode element and the second movable electrode element, which is arranged next to the other side in the first direction of the first movable electrode element, are connected to each other via the insulating joining connection, and these form a movable electrode element of a second set, and each of a plurality of movable electrode elements of the second set and each of the plurality of second fixed electrode elements are arranged alternately in the first direction. [Fourth aspect]

[0176] Accelerometer according to the third aspect, in which the movable electrode further includes a conductive path section extending in the first direction between the plurality of movable electrode elements of the first set and the plurality of movable electrode elements of the second set. [Fifth aspect]

[0177] Accelerometer according to the fourth aspect, in which The conductive path section includes the following: a first conductive path section that is mechanically connected to the plurality of movable electrode elements of the first set; and a second conductive path section that is mechanically connected to the multitude of movable electrode elements of the second set. [Sixth Aspect]

[0178] Accelerometer according to the fifth aspect, in which the first conductive path section includes a first section of the first conductive path that is electrically connected to the first movable electrode element, and a second section of the first conductive path that is electrically connected to the second movable electrode element, the second conductive path section includes a first section of the second conductive path that is electrically connected to the first movable electrode element, and a second section of the second conductive path that is electrically connected to the second movable electrode element, the first section of the first conductive path and the first section of the second conductive path are electrically connected, and the second section of the first conductive path and the second section of the second conductive path are electrically connected. [Seventh aspect]

[0179] Accelerometer according to the sixth aspect, in which the first section of the first conductive path and the second section of the first conductive path are connected via the insulating joint and the first section of the second conductive path and the second section of the second conductive path are connected via the insulating joint. [Eighth Aspect]

[0180] Accelerometer according to the seventh aspect, in which the first conductive path section and the second conductive path section are connected via the insulating joint. [Ninth aspect]

[0181] Accelerometer according to the eighth aspect, in which the first section of the first conductive path and the first section of the second conductive path are electrically connected via a first wiring layer and The second section of the first conductive path and the second section of the second conductive path are electrically connected via a second wiring layer that differs from the first wiring layer. [Tenth aspect]

[0182] Accelerometer according to one of the sixth to ninth aspects, wherein each of the first conductive path section and the second conductive path section includes a spring section that deforms elastically in the first direction at both end sections. [Eleventh aspect]

[0183] Accelerometer according to one of the third to tenth aspects, which further includes the following in top view in the recessed section: a third area, located adjacent to the first area in the first direction; and a fourth area, which lies next to the second area in the first direction and next to the third area in the second direction, where the first capacitor and the second capacitor are also located in the fourth area in addition to the first area and The second capacitor and the third capacitor are located in the third area in addition to the second area. [Twelfth Aspect]

[0184] Accelerometer, which includes the following: a substrate with a first main surface and a second main surface opposite the first main surface; a recessed section that extends from the first main surface towards the second main surface and is defined by a plurality of wall surfaces of the recessed section; an anchor protruding from an anchor area which is a sub-area of ​​a first wall surface which is included in the multitude of wall surfaces of the recessed section; a supporting frame, one end section of which is connected to the anchor and extends into the recessed section, the supporting frame being separated from the multitude of wall surfaces of the recessed section; a MEMS electrode located in the recessed section; and an insulating joint that mechanically connects the MEMS electrode to the support frame and simultaneously electrically insulates the MEMS electrode from the support frame. [Thirteenth aspect]

[0185] Accelerometer according to the twelfth aspect, in which the anchor area is located in the ground surface of the sunken section, which is a ground surface of the sunken section. [Fourteenth Aspect]

[0186] Accelerometer according to the thirteenth aspect, in which The anchor area has a width dimension of 2.5 µm or more and 25 µm or less. [Fifteenth aspect]

[0187] Accelerometer according to the fourteenth aspect, in which The anchor area, viewed from above, includes the center of the ground surface of the sunken section. [Sixteenth Aspect]

[0188] Accelerometer according to the fifteenth aspect, in which The anchor, when viewed from above, has a center that coincides with the center of the ground surface of the sunken section. [Seventeenth Aspect]

[0189] Accelerometer according to one of the twelfth to sixteenth aspects, wherein The support frame includes the following: an anchor connection frame extending from the anchor towards the wall surface of the recessed section; and a base frame that is rigidly connected directly or indirectly to the anchor connection frame, the base frame extending along a plurality of the wall surfaces of the recessed section around the MEMS electrode. [Eighteenth Aspect]

[0190] Accelerometer according to the seventeenth aspect, in which The MEMS electrode is supported by the base frame. [Nineteenth Aspect]

[0191] Accelerometer according to one of the twelfth to eighteenth aspects, wherein The MEMS electrode includes the following: a solid electrode comprising a multitude of solid electrode elements; and a movable electrode comprising a plurality of movable electrode elements facing a plurality of fixed electrode elements, [Twentieth aspect]

[0192] Accelerometer according to the nineteenth aspect, in which The anchor includes the following: a first anchor; and a second anchor that is separate from the first anchor. [Twenty-first aspect]

[0193] Accelerometer according to the twentieth aspect, in which the movable electrode further includes a conductive path section that is connected to a plurality of the movable electrode elements, and the conductive path segment between the first anchor and the second anchor extends in a second direction that intersects a first direction in which the first anchor and the second anchor are aligned. [Twenty-second aspect]

[0194] Accelerometer according to the twenty-first aspect, in which The fixed electrode and the movable electrode are connected to the wall surface of the recessed section via a flexible conductor that is conductive and elastically deformable. DESCRIPTION OF REFERENCE MARKS 1 accelerometer 2 device-side substrate 3 Sensor unit 4 electrode pads 6 MEMS electrode 7 fixed electrode 8 movable electrode 8A movable electrode element of the first set 8B movable electrode element of the second set 9 Insulating joint or insulating seam 10 in-depth section 11 Wall surface of the recessed section 12. Ground surface of the excavated section 18 insulating film 20 first solid electrode 21 first fixed electrode element 22 Base section of the first solid electrode 23 Extension section of the first fixed electrode 30 second fixed electrode 31 second fixed electrode element 32 Base section of the second fixed electrode 33 Extension section of the second fixed electrode 40 first movable electrode 41 first movable electrode element 42 first wiring layer 44 third wiring layer 50 second movable electrode 51 second movable electrode element 52 second wiring layer 54 fourth wiring layer 60 conductive path section 61 first conductive path section 62 first section of the first conductive path 63 second section of the first conductive path 64 First wiring layer of the connection section 65 second conductive path section 66 first section of the second conductive path 67 second section of the second conductive path 68 second wiring layer of the connection section 69 Connecting section of the conductive path 71 first spring section 72 second spring section 73 third spring section 74 fourth spring section 76 Base section of the first conductive path 78 Base section of the second conductive path 81 first flexible line or first flexible connection (“lead”) 82 second flexible line 83 third flexible line 84 fourth flexible line 85 fifth flexible line 86 sixth flexible line 87 seventh flexible line 88 eighth flexible line 89a ninth flexible line 89b tenth flexible line 90 frames 91 anchors 91a first anchor 91b second anchor 92 support frames 93 Anchor connection frames 93a first connecting frame 93b second connecting frame 94 base frames 95 first base frame 96 second base frame QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2019-49434 A

[0005]

Claims

[1] Acceleration sensor comprising: a substrate having a first main surface and a second main surface opposite the first main surface; a recessed portion recessed from the first main surface toward the second main surface; a MEMS electrode provided in the recessed portion and comprising a fixed electrode including a first fixed electrode and a second fixed electrode electrically insulated from the first fixed electrode, and a movable electrode including a first movable electrode and a second movable electrode electrically insulated from the first movable electrode, forming a differential circuit; and an insulating joint that mechanically connects the first movable electrode and the second movable electrode and simultaneously electrically isolates the first movable electrode and the second movable electrode. [2] Acceleration sensor according to claim 1, wherein the first fixed electrode includes a plurality of first fixed electrode elements, the second fixed electrode includes a plurality of second fixed electrode elements, the first movable electrode includes a plurality of first movable electrode elements, the second movable electrode includes a plurality of second movable electrode elements, and the MEMS electrode includes: a first capacitor including the plurality of first fixed electrode elements and the plurality of first movable electrode elements facing each of the plurality of first fixed electrode elements in a first direction; a second capacitor including the plurality of first fixed electrode elements and the plurality of second movable electrode elements facing each of the plurality of first fixed electrode elements in the first direction; a third capacitor including the plurality of second fixed electrode elements and the plurality of first movable electrode elements facing each of the plurality of second fixed electrode elements in the first direction; and a fourth capacitor including the plurality of second fixed electrode elements and the plurality of second movable electrode elements facing each of the plurality of second fixed electrode elements in the first direction, and wherein, when the first movable electrode and the second movable electrode are displaced in the first direction in a state where input voltages of opposite phases are input to the first movable electrode and the second movable electrode, output voltages of opposite phases are output from the first fixed electrode and the second fixed electrode. [3] The acceleration sensor according to claim 2, wherein the MEMS electrode in plan view includes: the first capacitor and the second capacitor in a first region located on one side in a second direction orthogonal to the first direction; and the third capacitor and the fourth capacitor in a second region located on the other side in the second direction, wherein in the first region, the first movable electrode element and the second movable electrode element arranged adjacent to one side in the first direction of the first movable electrode element are connected to each other via the insulating joint, forming a movable electrode element of a first set, and wherein each of a plurality of the movable electrode elements of the first set and each of the plurality of first fixed electrode elements are arranged alternately in the first direction, and wherein in the second region, the first movable electrode element and the second movable electrode element arranged adjacent to the other side in the first direction of the first movable electrode element are connected to each other via the insulating joint,wherein these form a movable electrode element of a second set, and wherein each of a plurality of movable electrode elements of the second set and each of the plurality of second fixed electrode elements are arranged alternately in the first direction. [4] The acceleration sensor according to claim 3, wherein the movable electrode further includes a conductive path portion extending in the first direction between the plurality of movable electrode elements of the first set and the plurality of movable electrode elements of the second set. [5] An acceleration sensor according to claim 4, wherein the conductive path portion includes: a first conductive path portion mechanically connected to the plurality of movable electrode elements of the first set; and a second conductive path portion mechanically connected to the plurality of movable electrode elements of the second set. [6] Acceleration sensor according to claim 5, wherein the first conductive path portion includes a first portion of the first conductive path electrically connected to the first movable electrode element and a second portion of the first conductive path electrically connected to the second movable electrode element, the second conductive path portion includes a first portion of the second conductive path electrically connected to the first movable electrode element and a second portion of the second conductive path electrically connected to the second movable electrode element, the first section of the first conductive path and the first section of the second conductive path are electrically connected, and the second portion of the first conductive path and the second portion of the second conductive path are electrically connected. [7] Acceleration sensor according to claim 6, wherein the first section of the first conductive path and the second section of the first conductive path are connected via the insulating joint and the first section of the second conductive path and the second section of the second conductive path are connected via the insulating joint. [8] The acceleration sensor according to claim 7, wherein the first conductive path portion and the second conductive path portion are connected via the insulating joint. [9] Acceleration sensor according to claim 8, wherein the first section of the first conductive path and the first section of the second conductive path are electrically connected via a first wiring layer and the second portion of the first conductive path and the second portion of the second conductive path are electrically connected via a second wiring layer different from the first wiring layer. [10] An acceleration sensor according to any one of claims 6 to 9, wherein each of the first conductive path portion and the second conductive path portion includes a spring portion elastically deforming in the first direction at both end portions. [11] Acceleration sensor according to one of claims 3 to 10, further comprising in plan view in the recessed portion: a third area adjacent to the first area in the first direction; and a fourth region adjacent to the second region in the first direction and adjacent to the third region in the second direction, wherein the first capacitor and the second capacitor are also located in the fourth region in addition to the first region and the second capacitor and the third capacitor are located in the third region in addition to the second region.

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