Vibration element, method for manufacturing the same, physical quantity sensor, and inertial measurement device

Abstract

Provided are a vibrating element, a method for manufacturing the same, a physical quantity sensor, and an inertial measurement device. The vibrating element is characterized by including a base portion, a vibrating arm extending from the base portion and having an arm portion and a weight application portion, and a weight application film disposed on the weight application portion. The weight application portion has a first main surface and a second main surface in a positive and negative relationship. A center of gravity of the weight application portion is located on a side of the first main surface relative to a center surface in a thickness direction of the arm portion. A center of gravity of the weight application film is located on a side of the second main surface relative to the center surface.

Description

[0001] This application is a divisional application of the invention patent application entitled "Vibration Element and Manufacturing Method Thereof, Physical Quantity Sensor, Inertial Measurement Device", filed on January 21, 2019, with application number 201910052463.5. Technical Field

[0002] This invention relates to vibration elements, methods for manufacturing vibration elements, physical quantity sensors, inertial measurement devices, electronic devices, and moving bodies. Background Technology

[0003] Previously, vibrating elements for devices such as quartz oscillators and vibrating gyroscope sensors were known. Patent Document 1, as an example of such a vibrating element, describes a tuning fork-type quartz resonator having a base and a pair of vibrating arms extending in parallel from the base. Here, at the end of each vibrating arm is a weighted portion, processed to be thinner than the arm portion of the vibrating arm, and a metal film for adjusting the frequency of the tuning fork-type quartz resonator is provided on the weighted portion. Furthermore, Patent Document 2 describes a tuning fork-type piezoelectric resonator having a base and a pair of vibrating arms extending in parallel from the base, with a portion thinner than a predetermined thickness formed on the weighted portion at the end, where the width is greater than the arm portion of the vibrating arm. A metal film for adjusting the frequency is provided on both the upper and lower surfaces of this weighted portion.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2006-311444

[0005] Patent Document 2: Japanese Patent Application Publication No. 2010-213262

[0006] However, in the tuning fork type quartz oscillator described in Patent Documents 1 and 2, the center of gravity of the structure consisting of the weighting part and the metal film deviates in the thickness direction relative to the center plane of the arm portion of the oscillating arm. Therefore, when a pair of oscillating arms vibrate in directions close to or separated from each other (in-plane direction), the oscillating arms will generate vibrations containing a component in the thickness direction (out-of-plane direction). As a result, there is a problem that the vibration component in the thickness direction leaks out of the oscillating element through the base and becomes a source of noise vibration from the outside of the oscillating element. Summary of the Invention

[0007] The purpose of this invention is to provide a vibration element capable of reducing noise vibration to the outside of the vibration element and a method for manufacturing the same, and to provide a physical quantity sensor, inertial measurement device, electronic device and moving body having the vibration element.

[0008] This invention was made to solve at least some of the above-mentioned problems and can be implemented as the following application examples or methods.

[0009] The vibration element of this application example has: a base; a vibration arm extending from the base, having an arm portion located on the base side and a weighting portion located at a position closer to the end of the arm portion; and a weighting membrane disposed on the weighting portion. The vibration element is characterized in that the weighting portion has a first main surface and a second main surface that are in opposite directions in the thickness direction of the vibration element, the center of gravity of the weighting portion is located at a position closer to the first main surface than the center surface of the arm portion in the thickness direction, and the center of gravity of the weighting membrane is located at a position closer to the second main surface than the center surface of the arm portion in the thickness direction.

[0010] According to this vibrating element, the center of gravity of the weighting part is located on the side closer to the first main surface than the center plane of the arm in the thickness direction, while the center of gravity of the weighting membrane is located on the side closer to the second main surface than the center plane of the arm in the thickness direction. Therefore, the center of gravity of the structure composed of the weighting part and the weighting membrane can be made close to this center plane (the center in the thickness direction of the vibrating arm). As a result, the unwanted vibration (vibration in the thickness direction) of the vibrating arm can be reduced, and consequently, the noise vibration to the outside of the vibrating element can be reduced.

[0011] In the vibration element of this application example, it is preferable that the weight-applying part has a first part and a second part that is thinner than the first part, and the second main surface has a stepped shape by utilizing the first part and the second part.

[0012] Therefore, with a relatively simple structure, the center of gravity of the weight-bearing part can be located on the side of the first main surface closer to the center surface in the thickness direction of the arm part.

[0013] In the vibration element of this application example, it is preferable that, when viewed in a plane from the thickness direction of the weight-bearing portion, the weight-bearing portion has a portion whose thickness gradually decreases between the first portion and the second portion.

[0014] Therefore, the weighting film can be easily and continuously formed across the first and second parts. Furthermore, cracks in the weighting film caused by the steps between the first and second parts can be reduced.

[0015] In the vibration element of this application example, it is preferable that, when viewed in a plane from the thickness direction, the width of the weight-bearing portion is greater than the width of the arm portion.

[0016] This increases the area of ​​the weight-applying section that can form the weight-applying film.

[0017] In the vibration element of this application example, it is preferable that the second part is disposed on both sides of the vibration arm in the width direction relative to the first part.

[0018] This reduces the torsional torque of the vibrating arm.

[0019] In the vibration element of this application example, it is preferable that the second part is disposed on the side opposite to the base relative to the first part.

[0020] This reduces the area of ​​the second part when viewed from a plane. Furthermore, it has the advantage that the mass in the width direction of the weighted part is less likely to become unbalanced.

[0021] In the vibration element of this application example, it is preferable that, when viewed in a plane from the thickness direction of the weight-bearing portion, the first portion is configured to surround the second portion.

[0022] Therefore, the design of Part 2 becomes easier.

[0023] In the vibration element of this application example, it is preferable that the first main surface is a flat surface.

[0024] Therefore, there is no need to process the first main surface side of the weight-bearing part to set the first part and the second part on the weight-bearing part, which simplifies the manufacturing process of the vibration element.

[0025] In the vibration element of this application example, it is preferable that the weight-applying membrane is disposed on the first part and the second part.

[0026] This allows for an increase in the mass of the weighted film. Furthermore, it simplifies the formation of the weighted film.

[0027] In the vibration element of this application example, it is preferable that the arm has a shape that is symmetrical about the center plane of the arm in the thickness direction.

[0028] This reduces vibration in the thickness direction caused by the shape of the vibrating arm.

[0029] In the vibration element of this application example, it is preferable that the vibration element has: a first vibration arm as the vibration arm, the first vibration arm extending from the base having a first arm portion as the arm portion and a first weighting portion as the weighting portion; a second vibration arm extending from the base, having a second arm portion located on the base side and a second weighting portion located on the end side of the second arm portion; a first weighting film as the weighting film disposed on the first weighting portion; and a second weighting film disposed on the second weighting portion, the center of gravity of the second weighting portion being located on the side of the first main surface closer to the center surface in the thickness direction of the second arm portion, and the center of gravity of the second weighting film being located on the side of the second main surface closer to the center surface in the thickness direction of the second arm portion.

[0030] This reduces unwanted vibrations (vibrations in the thickness direction) between the first and second vibrating arms. Furthermore, the centers of gravity of both the first and second weighting portions are located on the first main surface side (the same side as each other), and the centers of gravity of both the first and second weighting films are located on the second main surface side (the same side as each other), thus making it easy to form these weighting portions and films.

[0031] In the vibration element of this application example, preferably, the vibration element includes: a drive arm that drives vibration; and a detection arm that deforms in response to inertial force, the base having a base body and a connecting portion extending from the base body, the drive arm being the vibration arm extending from the connecting portion, and the detection arm extending from the base body.

[0032] Therefore, it is possible to improve the characteristics of so-called double-T type vibrating elements.

[0033] In the vibration element of this application example, preferably, the vibration element includes: a drive arm that extends from the base to drive vibration; and a detection arm that extends from the base in the opposite direction to the drive arm and deforms in response to inertial force, wherein the drive arm is the vibration arm.

[0034] Therefore, it is possible to improve the characteristics of so-called H-type vibrating elements.

[0035] In the vibration element of this application example, it is preferable that the weighting membrane has a first weighting membrane and a second weighting membrane with a thickness thinner than the first weighting membrane.

[0036] Therefore, when adjusting the resonant frequency of the vibrating arm by removing a portion of the weighting membrane using energy lines such as lasers, it is possible to easily perform fine and coarse adjustments.

[0037] The manufacturing method of the vibration element in this application example is characterized by comprising the following steps: forming a base and a vibration arm, the vibration arm extending from the base and having a first main surface and a second main surface that are opposite in the thickness direction, the center of gravity of the vibration arm being closer to the first main surface than the center surface of the vibration arm in the thickness direction; forming a weighting film on the vibration arm, the center of gravity of the weighting film being closer to the second main surface than the center surface of the vibration arm in the thickness direction; and adjusting the resonant frequency of the vibration arm by adjusting the mass of the weighting film.

[0038] According to this method of manufacturing the vibrating element, the characteristics of the obtained vibrating element can be improved. In addition, since the weighting membrane can be disposed only on one side of the weighting part (specifically, the second main side), the manufacturing process of the vibrating element can be simplified, and a portion of the weighting membrane can be removed by using energy lines such as lasers, thereby reducing the amount of scum generated when adjusting the resonant frequency of the vibrating arm.

[0039] The physical quantity sensor of this application example is characterized by having: the vibration element of this application example; and a package housing the vibration element.

[0040] Based on such a physical quantity sensor, the sensor characteristics (e.g., detection accuracy) can be improved by utilizing the superior characteristics of the vibration element.

[0041] The inertial measurement device of this application example is characterized by having: a physical quantity sensor of this application example; and a circuit electrically connected to the physical quantity sensor.

[0042] Based on such an inertial measurement device, the characteristics of the inertial measurement device (e.g., measurement accuracy) can be improved by utilizing the excellent sensor characteristics of physical quantity sensors.

[0043] The electronic device of this application example is characterized in that it has a vibration element of this application example.

[0044] According to such an electronic device, the superior characteristics of the vibrating element can be utilized to improve the characteristics (e.g., reliability) of the electronic device.

[0045] The moving body in this application example is characterized in that it has a vibration element of this application example.

[0046] Based on such a moving body, the characteristics of the moving body (e.g., reliability) can be improved by utilizing the superior characteristics of the vibrating element. Attached Figure Description

[0047] Figure 1 This is a plan view showing the vibration element according to the first embodiment of the present invention.

[0048] Figure 2 It is along Figure 1 A cross-sectional view along line AA in the diagram.

[0049] Figure 3 It is a plan view showing the weight-applying part and weight-applying membrane of the vibrating arm (drive arm) of the vibrating element, magnified.

[0050] Figure 4 It is along Figure 3 A cross-sectional view of the BB line.

[0051] Figure 5 It is along Figure 3 A cross-sectional view of the CC line.

[0052] Figure 6 This is a flowchart illustrating an example of a method for manufacturing a vibrating element.

[0053] Figure 7 This is a cross-sectional view showing the process of preparing the substrate in the vibrating plate forming process.

[0054] Figure 8 This is a cross-sectional view showing the process of forming a corrosion-resistant film and a photoresist film in the vibrating plate forming process.

[0055] Figure 9 This is a cross-sectional view showing the process of forming the shape of the vibrating plate in the vibrating plate forming process.

[0056] Figure 10 This is a cross-sectional view showing a process in which a portion of the corrosion-resistant film is removed during the vibrating plate forming process.

[0057] Figure 11 This is a cross-sectional view showing the process of forming the groove in the vibrating plate forming process.

[0058] Figure 12 This is a cross-sectional view showing the process of removing the corrosion-resistant film and the photoresist film in the vibrating plate forming process.

[0059] Figure 13 This is a cross-sectional view showing the electrode forming process.

[0060] Figure 14 This is a cross-sectional view showing the weighted film formation process.

[0061] Figure 15 This is a cross-sectional view showing the frequency adjustment process.

[0062] Figure 16 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the second embodiment of the present invention.

[0063] Figure 17 It is along Figure 16 A cross-sectional view of the CC line.

[0064] Figure 18 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the third embodiment of the present invention.

[0065] Figure 19 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the fourth embodiment of the present invention.

[0066] Figure 20 It is along Figure 19A cross-sectional view of the BB line.

[0067] Figure 21 This is a plan view showing the vibration element according to the fifth embodiment of the present invention.

[0068] Figure 22 This is a plan view showing the vibration element according to the sixth embodiment of the present invention.

[0069] Figure 23 This is a cross-sectional view illustrating a physical quantity sensor according to an embodiment of the present invention.

[0070] Figure 24 This is an exploded perspective view showing an embodiment of the inertial measuring device of the present invention.

[0071] Figure 25 yes Figure 24 The diagram shows a three-dimensional view of the substrate of the inertial measurement device.

[0072] Figure 26 This is a perspective view showing an embodiment of the electronic device of the present invention (a mobile (or notebook) personal computer).

[0073] Figure 27 This is a plan view illustrating an embodiment (mobile phone) of the electronic device of the present invention.

[0074] Figure 28 This is a perspective view illustrating an embodiment of the electronic device of the present invention (digital still camera).

[0075] Figure 29 This is a perspective view showing an embodiment (automobile) of the mobile body of the present invention.

[0076] Label Explanation

[0077] 1: Vibrating element; 1A: Vibrating element; 1B: Vibrating element; 1C: Vibrating element; 1D: Vibrating element; 1E: Vibrating element; 2: Vibrating plate; 2D: Vibrating plate; 2E: Vibrating plate; 2a: First main surface; 2b: Second main surface; 3: Weighting film; 3D: Weighting film; 4: Electrode film; 10: Physical quantity sensor; 11: Encapsulation; 12: Support component; 13: Circuit element; 14: Connecting terminal; 15: Connecting terminal; 16: Terminal; 17: Conductive adhesive; 19: Adhesive; 20: Quartz substrate; 20A: Quartz substrate; 21: Base; 21D: Base; 21E: Base; 22: Detection arm; 22D: Detection arm; 23: Detection arm; 23D: Detection arm; 24: Drive arm; 2 4A: Drive arm; 24B: Drive arm; 24C: Drive arm; 24D: Drive arm; 24E: Vibrating arm; 25: Drive arm; 25D: Drive arm; 25E: Vibrating arm; 26: Drive arm; 27: Drive arm; 31: Weighting film; 31D: Weighting film; 32: Weighting film; 32D: Weighting film; 33: Weighting film; 33D: Weighting film; 33E: Weighting film; 34: Weighting film; 34D: Weighting film; 34E: Weighting film; 35: Weighting film; 36: Weighting film; 41: Drive signal electrode; 42: Drive ground electrode; 43: Detection signal electrode; 44: Detection ground electrode; 51: Corrosion resistant film; 52: Corrosion resistant film; 52A: Corrosion resistant film; 53: Resistant film; 54: Resistant film; 1 11: Base; 112: Cover; 113: Connecting component; 121: Support substrate; 122: Wiring pattern; 123: Protrusion; 211: Base body; 212: Connecting arm; 213: Connecting arm; 214: First base; 215: Connecting part; 216: Second base; 221: Arm; 222: Weight-bearing part; 223: Groove; 231: Arm; 232: Weight-bearing part; 233: Groove; 241: Arm; 242: Weight-bearing part; 242A: Weight-bearing part; 242B: Weight-bearing part; 242C: Weight-bearing part; 242a: First part; 242b: Second part; 242c: Second part; 242d: First part; 242e: Second part; 242f: First part; 242g: Second part Part; 242h: Part 2; 242i: Part 1; 243: Groove; 244: Step; 245: Step; 247: Recess; 251: Arm; 252: Weight-bearing part; 253: Groove; 261: Arm; 262: Weight-bearing part; 263: Groove; 271: Arm; 272: Weight-bearing part; 273: Groove; 1100: Personal computer; 1102: Keyboard; 1104: Main body; 1106: Display unit; 1108: Display part; 1200: Mobile phone; 1202: Operation button; 1204: Answering port; 1206: Talking port; 1208: Display part; 1300: Digital still camera; 1302: Housing; 1304: Light receiving unit; 1306: Shutter button;1308: Memory; 1310: Display unit; 1500: Automobile; 1501: Vehicle body; 1502: Vehicle body attitude control device; 1503: Wheel; 2000: Inertial measurement unit; 2100: Housing; 2110: Threaded hole; 2200: Connecting component; 2300: Sensor module; 2310: Inner shell; 2311: Recess; 2312: Opening; 2320: Substrate; 2330: Connector; 2340X: Angular velocity sensor; 2340Y: Angular velocity sensor Sensors; 2340Z: Angular velocity sensor; 2350: Accelerometer sensor; 2360: Control IC; A1: Arrow; A2: Arrow; B1: Arrow; B2: Arrow; C: Center; C1: Arrow; C2: Arrow; G: Center of gravity; G1: Center of gravity; G2: Center of gravity; LL: Energy line; S10: Vibrator forming process; S20: Electrode forming process; S30: Weighting film forming process; S40: Frequency adjustment process; a: Arrow; b: Arrow; c: Arrow; ω: Angular velocity; Detailed Implementation

[0078] The vibration element, the method for manufacturing the vibration element, the physical quantity sensor, the inertial measurement device, the electronic device, and the moving body of the present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings.

[0079] 1. Vibrating elements and their manufacturing methods

[0080] <First Implementation>

[0081] First, the vibration element and its manufacturing method will be explained.

[0082] (Vibrating element)

[0083] Figure 1 This is a plan view showing the vibration element according to the first embodiment of the present invention. Figure 2 It is along Figure 1 A cross-sectional view along line AA in the diagram. Figure 3 It is a plan view showing the weight-applying part and weight-applying membrane of the vibrating arm (drive arm) of the vibrating element, magnified. Figure 4 It is along Figure 3 A cross-sectional view of the BB line. Figure 5 It is along Figure 3 The cross-sectional view along the CC line is shown in the figures. The dimensions of each component are exaggerated as needed, and the aspect ratios of the components may not necessarily match the actual aspect ratios. The positions, orientations, and sizes of the components described below also include manufacturing tolerances (e.g., within ±1%), and are not limited to the positions, orientations, and sizes described in this specification, as long as the necessary functions of each component are achieved.

[0084] In addition, for ease of explanation, we will use three mutually perpendicular axes—the x-axis, y-axis, and z-axis—for the following explanation. The direction parallel to the x-axis will be called the "x-axis direction," the direction parallel to the y-axis will be called the "y-axis direction," and the direction parallel to the z-axis will be called the "z-axis direction." In the diagram, the end of the arrow representing the x-axis, y-axis, and z-axis will be labeled "+," and the base will be labeled "-." Furthermore, the +z-axis direction will be called "up," the -z-axis direction will be called "down," the +x-axis direction will be called "right," and the -x-axis direction will be called "left." Finally, viewing from the z-axis direction will be referred to as "planar viewing." Figure 1 For ease of explanation, the diagram of electrode film 4, which will be described later, is omitted.

[0085] Figure 1 The vibration element 1 shown is a sensor element for detecting the angular velocity about the z-axis. This vibration element 1 includes: a vibrating plate 2 (see reference). Figure 1 ); Electrode film 4 disposed on vibrating plate 2 (refer to Figure 2 ); and the weighting film 3 disposed on the electrode film 4 (refer to Figure 1 ).

[0086] like Figure 1 As shown, the vibrating plate 2 has a so-called double-T structure. Specifically, the vibrating plate 2 has a base 21, a pair of detection arms 22 and 23 (first and second detection arms) extending from the base 21, a pair of drive arms 24 and 25 (first drive arm) and a pair of drive arms 26 and 27 (second drive arm).

[0087] Here, the base 21 has: a base body 211, which is supported on the package 11 described later (see reference). Figure 23 The base body 211 has a connecting arm 212 extending along the +x-axis direction; and a connecting arm 213 extending along the -x-axis direction, opposite to the extension direction of the connecting arm 212. Furthermore, a detection arm 22 (first detection arm) extends from the base body 211 along the +y-axis direction, intersecting the extension directions of the connecting arms 212 and 213. Conversely, a detection arm 23 (second detection arm) extends from the base body 211 along the -y-axis direction, opposite to the extension direction of the detection arm 22. A drive arm 24 (first drive arm) extends from the end region of the connecting arm 212 along the +y-axis direction. Conversely, a drive arm 25 (first drive arm) extends from the end region of the connecting arm 212 along the -y-axis direction, opposite to the extension direction of the drive arm 24. Similarly, drive arm 26 (second drive arm) extends from the end region of connecting arm 213 along the +y axis direction, while drive arm 27 extends from the end region of connecting arm 213 along the -y axis direction, which is opposite to the extension direction of drive arm 26.

[0088] Furthermore, the detection arm 22 has: an arm portion 221 (detection arm portion) extending from the base body 211; a weighting portion 222 (detection weighting portion) disposed at the end of the arm portion 221, which is wider than the arm portion 221; and slots 223 respectively disposed on the upper and lower surfaces of the arm portion 221. Similarly, the detection arm 23 has an arm portion 231 (detection arm portion), a weighting portion 232 (detection weighting portion), and a pair of slots 233. Furthermore, the drive arm 24 has: an arm portion 241 (drive arm portion) extending from the connecting arm 212; a weighting portion 242 (drive weighting portion) disposed at the end of the arm portion 241, which is wider than the arm portion 241; and a pair of slots 243 disposed on the upper and lower surfaces of the arm portion 241. Similarly, the drive arm 25 has an arm portion 251 (drive arm portion), a weighting portion 252 (drive weighting portion), and a pair of slots 253. Furthermore, the drive arm 26 includes: an arm portion 261 (drive arm portion) extending from the connecting arm 213; a weight-applying portion 262 (drive weight-applying portion) disposed at the end of the arm portion 261, having a width greater than the arm portion 261; and a pair of slots 263 disposed on the upper and lower surfaces of the arm portion 261. Similarly, the drive arm 27 includes an arm portion 271 (drive arm portion), a weight-applying portion 272 (drive weight-applying portion), and a pair of slots 273.

[0089] Furthermore, at least one of the upper and lower pairs of slots 223, 233, 243, 253, 263, and 273 may be omitted. Additionally, the upper and lower pairs of slots 223, 233, 243, 253, 263, and 273 may be interconnected. That is, through holes opening towards the upper and lower surfaces may also be provided on the arms 221, 231, 241, 251, 261, and 271. Furthermore, the width of the weighting portions 222, 232, 242, 252, 262, and 272 may be less than or equal to the width of the arms 221, 231, 241, 251, 261, and 271.

[0090] Here, arm 221 is the portion that bends (deforms) when the detection arm 22 vibrates (during vibration detection), and it is also the portion that detects the charge generated accompanying the detection vibration of the detection arm 22 (the portion equipped with the detection signal electrode 43 and the detection ground electrode 44, described later). Similarly, arm 231 is the portion that bends (deforms) when the detection arm 23 vibrates (during vibration detection), and it is also the portion that detects the charge generated accompanying the detection vibration of the detection arm 23 (the portion equipped with the detection signal electrode 43 and the detection ground electrode 44, described later). Furthermore, arm 241 is the portion that bends (deforms) when the drive arm 24 vibrates (during drive vibration), and it is also the portion for which an electric field is applied to drive the drive arm 24 (the portion equipped with the drive signal electrode 41 and the drive ground electrode 42, described later). Similarly, arms 251, 261, and 271 are the portions that bend (deform) when the drive arms 25, 26, and 27 vibrate (during drive vibration), and are also the portions where an electric field is applied to drive the drive arms 25, 26, and 27 (the portions equipped with drive signal electrodes 41 and drive ground electrodes 42, described later). Furthermore, the weight-applying portion 222 is the portion further to the end than arm 221. Likewise, weight-applying portions 232, 242, 252, 262, and 272 are the portions further to the end than arm 231, 241, 251, 261, and 271.

[0091] like Figure 3 As shown, the weight-bearing portion 242 has: a first portion 242a located on the extension line of the arm portion 241; and a pair of second portions 242b and 242c located on both sides of the first portion 242a in the width direction. Furthermore, as... Figure 4 As shown, the thickness t2 of each of the second portions 242b and 242c is thinner than the thickness t1 of the first portion 242a. Here, the first main surface 2a is flat, while the second main surface 2b is provided with steps 244 and 245 formed by the first portion 242a and the second portions 242b and 242c. These steps 244 and 245 are configured to include inclined surfaces, and the thickness of the weighting portion 242 gradually increases from the side of the second portions 242b and 242c toward the side of the first portion 242a. As will be described later, such second portions 242b and 242c can be formed by etching (anisotropic etching) the second main surface 2b of the weighting portion 242.

[0092] like Figure 4As shown, the center of gravity G1 of the weight-applying part 242 is located on the side of the first main surface 2a, which is opposite to the center C of the drive arm 24 in the thickness direction. That is, the center of gravity G1 of the weight-applying parts 242, 252, 262, and 272 is located on the side of the first main surface 2a, which is closer to the center surface CP in the thickness direction of the arm parts 241, 251, 261, and 271. In contrast, the center of gravity G2 of the weight-applying films 33, 34, 35, and 36 is located on the side of the second main surface 2b, which is closer to the center surface CP in the thickness direction of the arm parts 241, 251, 261, and 271. By shifting the center of gravity G1 relative to the center C in the thickness direction in such a manner, as described later, balance with the weighting membrane 33, which has a center of gravity G2 located on the opposite side to the center of gravity G1 of the weighting section 242, can be achieved. Similarly, the centers of gravity G1 of the weighting sections 252, 262, and 272 are located on the first main surface 2a side of the first main surface 2a (lower surface) and the second main surface 2b (upper surface) of the weighting sections 252, 262, and 272, respectively, relative to the center C in the thickness direction of the drive arms 25, 26, and 272. Furthermore, the centers of gravity of the weighting sections 222 and 232 are also located on the first main surface side of the first main surface (lower surface) and the second main surface (upper surface) of the weighting sections 222 and 232, respectively, relative to the center in the thickness direction of the detection arms 22 and 23.

[0093] Here, "the center plane CP in the thickness direction of arm 241" is a plane perpendicular to the thickness direction (z-axis direction) of arm 241, and is a plane whose distances in the thickness direction on the first main surface 2a side and the second main surface 2b side are equal. Furthermore, the center planes in the thickness direction of arms 251, 261, and 271 are also defined in the same way as the center plane CP in the thickness direction of arm 241. "Weighting film 33" refers to a laminate (on the drive arm 24) whose mass per unit area is greater than that of the electrode films 4 (drive signal electrode 41 and drive ground electrode 42) of arm 241. Furthermore, the weighting films 34, 35, and 36 are also defined in the same way as the weighting film 33.

[0094] Furthermore, the difference between the depth d1 of the steps 244 and 245 of the second main surface 2b, i.e., the thickness t1 of the first part 242a and the thickness t2 of the second parts 242b and 242c, is not particularly limited, but is preferably equal to the depth d2 of the groove 243 (see reference). Figure 5 Thus, the aforementioned steps 244 and 245 can be formed together with the groove 243 through etching. The depth d1 of the step is preferably 0.1 to 0.5 times the thickness t1 of the weighting portion 242, more preferably 0.15 to 0.4 times.

[0095] Furthermore, the widths Wb and Wc of the second portions 242b and 242c can be equal or unequal, but preferably the width Wc of the second portion 242c is greater than the width Wb of the second portion 242b. In the case where the vibrating plate 2 is formed by anisotropic etching of a Z-cut quartz plate, the average thickness of the second portion 242b is greater than the average thickness of the second portion 242c due to the anisotropy of the vibrating plate 2. Therefore, by making the width Wc of the second portion 242c greater than the width Wb of the second portion 242b, it is possible to make the mass of the second portion 242b equal to the mass of the second portion 242c.

[0096] Furthermore, the widths Wb and Wc of the specific second parts 242b and 242c are determined based on the thickness and area of ​​the weighting film 33 described later, and are not particularly limited, but are approximately 0.3 to 0.8 times the width Wa of the first part 242a. Additionally, the areas of the second parts 242b and 242c in planar view are not particularly limited, but are, for example, approximately 0.1 to 2 times the area of ​​the first part 242a in planar view.

[0097] The vibrator 2 is constructed from a Z-cut quartz plate. By using quartz (Z-cut quartz plate) to construct the vibrator 2, its vibration characteristics (especially its frequency-temperature characteristics) are excellent. Furthermore, the vibrator 2 can be formed with high dimensional accuracy through etching. Quartz belongs to the trigonal crystal system and has mutually perpendicular X-axis, Y-axis, and Z-axis as crystal axes. The X-axis, Y-axis, and Z-axis are respectively called the electrical axis, mechanical axis, and optical axis. The Z-cut quartz plate is a quartz substrate that is plate-shaped, extends in the XY plane defined by the Y-axis (mechanical axis) and X-axis (electric axis), and has thickness in the Z-axis (optical axis) direction. Here, the X-axis of the quartz constituting the vibrator 2 is parallel to the x-axis, the Y-axis is parallel to the y-axis, and the Z-axis is parallel to the z-axis.

[0098] Alternatively, the vibrating plate 2 can also be made of a piezoelectric material other than quartz. Examples of piezoelectric materials other than quartz include lithium tantalate, lithium niobate, lithium borate, and barium titanate. Furthermore, depending on the structure of the vibrating plate 2, it can also be made of a quartz plate with bevels other than Z-cut. Additionally, the vibrating plate 2 can be made of a material other than a piezoelectric material (a material without piezoelectric properties), such as silicon. In this case, piezoelectric elements (elements formed by sandwiching a piezoelectric film made of PZT or the like between a pair of electrodes) can be arranged on each arm of the detection arms 22, 23 and the drive arms 24, 25, 26, 27.

[0099] An electrode film 4 is disposed on the surface of the vibrating plate 2 constructed in this way. For example... Figure 2As shown, the electrode film 4 has a drive signal electrode 41, a drive ground electrode 42, a detection signal electrode 43, a detection ground electrode 44, and multiple terminals (not shown) electrically connected to these electrodes.

[0100] The drive signal electrode 41 is used to excite the drive vibration of the drive arms 24, 25, 26, and 27. For example... Figure 2 As shown, drive signal electrodes 41 are respectively disposed on the upper and lower surfaces of the arm portion 241 of the drive arm 24 and on both sides of the arm portion 261 of the drive arm 26. Similarly, although not shown, drive signal electrodes 41 are respectively disposed on the upper and lower surfaces of the arm portion 251 of the drive arm 25 and on both sides of the arm portion 271 of the drive arm 27.

[0101] On the other hand, the drive ground electrode 42 has a potential (e.g., ground potential) relative to the drive signal electrode 41 as a reference. Figure 2 As shown, drive grounding electrodes 42 are respectively disposed on both sides of the arm portion 241 of drive arm 24 and on the upper and lower surfaces of the arm portion 261 of drive arm 26. Similarly, although not shown, drive grounding electrodes 42 are respectively disposed on both sides of the arm portion 251 of drive arm 25 and on the upper and lower surfaces of the arm portion 271 of drive arm 27.

[0102] The detection signal electrode 43 is an electrode that detects the charge generated by the detection vibration when the detection arm 22 is excited. For example... Figure 2 As shown, the detection signal electrode 43 is disposed on the upper and lower surfaces of the arm portion 221 of the detection arm 22.

[0103] On the other hand, the detection ground electrode 44 has a potential (e.g., ground potential) relative to the detection signal electrode 43 as a reference. Figure 2 As shown, the detection grounding electrode 44 is disposed on both sides of the arm portion 221 of the detection arm 22.

[0104] Furthermore, although not shown, detection signal electrodes for detecting the charge generated by the detection vibration when the detection arm 23 is excited are provided on the upper and lower surfaces of the arm portion 231 of the detection arm 23. Similarly, detection ground electrodes of the detection arm 23, having a potential (e.g., ground potential) relative to the detection signal electrodes of the detection arm 23 as a reference, are provided on both sides of the arm portion 231 of the detection arm 23. Moreover, vibration detection can also be performed using the differential signal between the detection signal electrodes 43 of the detection arm 22 and the detection signal electrodes of the detection arm 23.

[0105] The constituent materials of the electrode film 4 are not particularly limited. For example, metals such as gold (Au), gold alloys, platinum (Pt), aluminum (Al), aluminum alloys, silver (Ag), silver alloys, chromium (Cr), chromium alloys, copper (Cu), molybdenum (Mo), niobium (Nb), tungsten (W), iron (Fe), titanium (Ti), cobalt (Co), zinc (Zn), and zirconium (Zr), or transparent electrode materials such as ITO and ZnO, can be used. Among these materials, metals with gold as the main material (gold, gold alloys) or platinum are preferred. In addition, a layer of Ti, Cr, etc., can be provided between the electrode film 4 and the vibrating plate 2 as a base layer that prevents the electrode film 4 from peeling off from the vibrating plate 2.

[0106] Such an electrode film 4 has a portion disposed on the weighting portions 222, 232, 242, 252, 262, and 272 of the aforementioned vibrating plate 2. Furthermore, a weighting film 3 is disposed on the weighting portions 222, 232, 242, 252, 262, and 272, spaced apart from this portion. Alternatively, the electrode film 4 may not be disposed directly below the weighting film 3.

[0107] like Figure 1 As shown, the weighting membrane 3 includes: a weighting membrane 31 disposed on the weighting section 222; a weighting membrane 32 disposed on the weighting section 232; a weighting membrane 33 disposed on the weighting section 242; a weighting membrane 34 disposed on the weighting section 252; a weighting membrane 35 disposed on the weighting section 262; and a weighting membrane 36 disposed on the weighting section 272. Weighting membranes 31 and 32 are membranes that can be appropriately removed using energy lines such as laser beams to adjust the resonant frequencies of the detection arms 22 and 23. Furthermore, weighting membranes 33, 34, 35, and 36 are membranes that can be appropriately removed using energy lines such as laser beams to adjust the resonant frequencies of the drive arms 24, 25, 26, and 27.

[0108] The weight-applying membrane 33 is disposed on the second main surface 2b of the first main surface 2a (lower surface) and the second main surface 2b (upper surface) of the weight-applying portion 242, which are in a front-to-back relationship, and is not disposed on the first main surface 2a. Furthermore, the weight-applying membrane 33 is not disposed on the sides (left and right sides and end surface) of the weight-applying portion 242. In this embodiment, the weight-applying membrane 33 is provided across the entire width direction (x-axis direction) of the weight-applying portion 242, with a portion removed from the base end side of the weight-applying portion 242. Therefore, the weight-applying membrane 33 is disposed across the first portion 242a and the second portions 242b and 242c of the weight-applying portion 242.

[0109] like Figure 4As shown, the center of gravity G2 of such a weighting membrane 33 is located on the second main surface 2b side of the first main surface 2a (lower surface) and the second main surface 2b (upper surface) of the weighting part 242, which are in an opposing relationship, relative to the center C in the thickness direction of the drive arm 24. By shifting the center of gravity G2 relative to the center C in such a way, as previously described, balance with the weighting part 242, which has a center of gravity G1 located on the opposite side of the center of gravity G2 of the weighting membrane 33, can be achieved. Similarly, the weighting membranes 34, 35, and 36 are located on the second main surface 2b side of the first main surface 2a (lower surface) and the second main surface 2b (upper surface) of the weighting parts 252, 262, and 272, respectively, relative to the center C in the thickness direction of the drive arms 25, 26, and 27, which are in an opposing relationship. Furthermore, the centers of the weighting films 31 and 32 in the thickness direction relative to the detection arms 22 and 23 are located on the second main surface side of the first main surface (lower surface) and the second main surface (upper surface) of the weighting parts 222 and 232, which are in a positive-negative relationship.

[0110] Furthermore, the position, size, and extent of the weight-applying membranes 31 to 36 are not limited to those shown in the illustrations. For example, the weight-applying membranes 3 can also be disposed on the first main surface 2a and side surfaces of the weight-applying portions 222, 232, 242, 252, 262, and 272. In this case, the thickness and arrangement of the weight-applying membranes 33, 34, 35, and 36 (excluding weight-applying membranes 31 and 32) can be adjusted so that their center of gravity G2 is located on the side of the second main surface 2b. Additionally, the weight-applying membranes 3 can be disposed throughout the entire length direction (y-axis direction) of the weight-applying portions 222, 232, 242, 252, 262, and 272.

[0111] The constituent material of such a weighting film 3 is not particularly limited; for example, metals, inorganic compounds, resins, etc., can be used, but metals or inorganic compounds are preferred. Metals or inorganic compounds can be easily and precisely formed into films using vapor phase film deposition methods. Furthermore, the weighting films 31 to 36 composed of metals or inorganic compounds can be efficiently and precisely removed by irradiation with an energy beam. Thus, by forming the weighting film 3 from a film composed of metals or inorganic compounds, the frequency adjustment described later becomes more efficient and precise.

[0112] Examples of suitable metals include nickel (Ni), gold (Au), gold alloys, platinum (Pt), aluminum (Al), aluminum alloys, silver (Ag), silver alloys, chromium (Cr), chromium alloys, nickel (Ni), copper (Cu), molybdenum (Mo), niobium (Nb), tungsten (W), iron (Fe), titanium (Ti), cobalt (Co), zinc (Zn), and zirconium (Zr), and one or more of these can be used in combination. Among these materials, based on the viewpoint that the weighting film 3 can be formed using the same apparatus as the electrode film 4, Al, Cr, Fe, Ni, Cu, Ag, Au, Pt, or alloys containing at least one of these are also preferred as the metal. More specifically, the weighting film 3 is preferably a structure obtained by laminating an upper layer of Au (gold) on a base layer made of Cr (chromium). This results in excellent adhesion to the oscillator 2 or electrode film 4 formed using quartz, and allows for high-precision and efficient adjustment of the resonant frequency.

[0113] In addition, examples of such inorganic compounds include oxide ceramics such as alumina, silicon dioxide, titanium dioxide, zirconium oxide, yttrium oxide, and calcium phosphate, silicon nitride, aluminum nitride, nitride ceramics such as titanium nitride and boron nitride, carbide ceramics such as graphite and tungsten carbide, as well as ferroelectric materials such as barium titanate, strontium titanate, PZT, PLZT, and PLLZT. Among these materials, insulating materials such as silicon dioxide (SiO2), titanium dioxide (TiO2), and alumina (Al2O3) are preferred.

[0114] Furthermore, the thickness (average thickness) of the weighted film 3 is not particularly limited, but is, for example, between 10 nm and 10,000 nm.

[0115] The vibration element 1, constructed as described above, detects the angular velocity ω about the z-axis as follows. First, a voltage (drive signal) is applied between the drive signal electrode 41 and the drive ground electrode 42. Figure 1In the direction indicated by arrow a, drive arms 24 and 26 undergo bending vibration (drive vibration) by repeatedly approaching and separating from each other. Similarly, drive arms 25 and 27 undergo bending vibration (drive vibration) by repeatedly approaching and separating from each other in the same direction as the bending vibration described above. At this time, without applying an angular velocity to the vibrating element 1, drive arms 24, 25 and 26, 27 vibrate symmetrically about the yz plane passing through the center point (center of gravity G). Therefore, the base body 211, connecting arms 212, 213, and detection arms 22, 23 hardly vibrate. Furthermore, as described above, the centers of gravity G1 of the weighting parts 242, 252, 262, 272 and the centers of gravity G2 of the weighting membranes 33, 34, 35, 36 are located on opposite sides of the center C of the drive arms 24, 25, 26, 27. Therefore, the out-of-plane vibration of the drive arms 24, 25, 26, 27 can be reduced.

[0116] In the state (driving mode) where the drive arms 24-27 are driven to vibrate in this manner, when an angular velocity ω about the normal line (i.e., about the z-axis) passing through its center of gravity G is applied to the vibrating element 1, Coriolis forces are applied to the drive arms 24-27 respectively. As a result, the connecting arms 2212 and 213... Figure 1 The bending vibration occurs in the direction indicated by the middle arrow b. Simultaneously, to counteract this bending vibration, the detection arms 22 and 23 are excited in... Figure 1 The bending vibration (detected vibration) is in the direction indicated by the middle arrow c. Furthermore, through the detection vibration (detection mode) of such detection arms 22 and 23, a charge is generated between the detection signal electrode 43 and the detection ground electrode 44. The angular velocity ω applied to the vibrating element 1 can be determined from this charge.

[0117] As described above, the vibrating element 1 includes: a base 21; drive arms 24, 25, 26, and 27 extending from the base 21, having arm portions 241, 251, 261, and 271 located on the side of the base 21, and weight-bearing portions 242, 252, 262, and 272 located at positions closer to the ends of the arm portions 241, 251, 261, and 271; and weight-bearing membranes 33, 34, 35, and 36 disposed on the weight-bearing portions 242, 252, 262, and 272. Here, the weight-bearing portions 242, 252, 262, and 272 have a first main surface 2a and a second main surface 2b in a positive-negative relationship. Furthermore, the center of gravity G1 of the weight-applying parts 242, 252, 262, and 272 is located on the side closer to the first main surface 2a than the center plane CP in the thickness direction of the arm parts 241, 251, 261, and 271 (a plane passing through the center C in the thickness direction of the drive arms 24, 25, 26, and 27 and perpendicular to the z-axis). In contrast, the center of gravity G2 of the weight-applying membranes 33, 34, 35, and 36 is located on the side closer to the second main surface 2b than the center plane CP in the thickness direction of the arm parts 241, 251, 261, and 271.

[0118] According to this vibrating element 1, the center of gravity G1 of the weight-applying parts 242, 252, 262, and 272 is located closer to the first main surface 2a than the center plane CP in the thickness direction of the arms 241, 251, 261, and 271. Conversely, the center of gravity G2 of the weight-applying membranes 33, 34, 35, and 36 is located closer to the second main surface 2b than the center plane CP in the thickness direction of the arms 241, 251, 261, and 271. Therefore, the center of gravity of the entire structure composed of the weight-applying parts 242, 252, 262, and 272 and the weight-applying membranes 33, 34, 35, and 36 can be made close to the center plane CP (the center C of the driving arms 24, 25, 26, and 27). As a result, the unwanted vibration (vibration in the thickness direction) of the driving arms 24, 25, 26, and 27 can be reduced, and consequently, the noise vibration to the outside of the vibrating element 1 can be reduced. Furthermore, the manufacturing method will be described later. However, the weighting films 33, 34, 35, and 36 can be disposed only on one side of the weighting parts 242, 252, 262, and 272 (specifically, the second main surface 2b side). Therefore, the manufacturing process of the vibrating element 1 can be simplified, and a portion of the weighting films 33, 34, 35, and 36 can be removed using energy lines such as lasers, thereby reducing the droplets (debris) generated when adjusting the resonant frequency of the vibrating arm.

[0119] Furthermore, the center of gravity G1 of the weight-applying parts 242, 252, 262, and 272 is located on the same side of the first main surface 2a, and the center of gravity G2 of the weight-applying membranes 33, 34, 35, and 36 is located on the same side of the second main surface 2b. Therefore, it is easy to form these weight-applying parts 242, 252, 262, and 272 and weight-applying membranes 33, 34, 35, and 36. In addition, one of the drive arms 24, 25, 26, and 27 corresponds to the "first vibrating arm", and the other corresponds to the "second vibrating arm". Moreover, the first vibrating arm has any one of the arm portions 241, 251, 261, and 271 as the first arm portion, and has a weight-applying part of the weight-applying parts 242, 252, 262, and 272 that is connected to the first arm portion as the first weight-applying part. The second vibrating arm has a weight-applying portion, which is different from the first weight-applying portion, among arm portions 241, 251, 261, and 271, as the second arm portion, and also has a weight-applying portion, which is connected to the second arm portion, among weight-applying portions 242, 252, 262, and 272, as the second weight-applying portion. Furthermore, any one of weight-applying membranes 33, 34, 35, and 36 is disposed on the first weight-applying portion as the first weight-applying membrane, and any one of weight-applying membranes 33, 34, 35, and 36 is disposed on the second weight-applying portion as the second weight-applying membrane.

[0120] Here, the arms 241, 251, 261, and 271 preferably have shapes that are symmetrical about the center plane CP in the thickness direction. This reduces vibrations in the thickness direction caused by the shapes of the drive arms 24, 25, 26, and 27.

[0121] The vibration element 1 of this embodiment includes: drive arms 24, 25, 26, and 27 that drive vibration; and detection arms 22 and 23 that deform in response to inertial forces. The base 21 has a base body 211 and connecting arms 212 and 213 extending from the base body 211 as connecting portions. Furthermore, the drive arms 24, 25, 26, and 27 are vibration arms extending from the connecting arms 212 and 213, and the detection arms 22 and 23 extend from the base body 211. Therefore, the characteristics of the so-called double-T type vibration element 1 can be improved.

[0122] When viewed in a plane along the thickness direction of the weight-applying portion 242, the width W of the weight-applying portions 242, 252, 262, and 272 is greater than the width W0 of the arm portions 241, 251, 261, and 271. This increases the area of ​​the weight-applying portions 242, 252, 262, and 272 that can form the weight-applying membranes 33, 34, 35, and 36. Furthermore, the lengths of the drive arms 24, 25, 26, and 27 can be shortened, resulting in miniaturization of the vibrating element 1.

[0123] Furthermore, the weight-bearing part 242 has a first part 242a and second parts 242b and 242c, which are thinner than the first part 242a. Moreover, the second main surface 2b utilizes the first part 242a and the second parts 242b and 242c to form stepped steps 244 and 245. Thus, with a relatively simple structure, the center of gravity G1 of the weight-bearing part 242 can be located closer to the first main surface 2a than the center surface CP in the thickness direction of the arm part 241. Furthermore, the weight-bearing parts 252, 262, and 272 are also constructed in the same way as the weight-bearing part 242, achieving the same effect. Here, "step 244" refers to a shape in the first part 242a where the average distance from the center surface in the thickness direction of the weight-bearing part 242 to the second main surface 2b is greater than the average distance from the center surface in the thickness direction of the weight-bearing part 242 to the second main surface 2b in the second part 242b. The "center plane in the thickness direction of the weight-bearing part 242" is a plane perpendicular to the thickness direction of the weight-bearing part 242, and is a plane whose distances in the thickness direction on the first main surface 2a side and the second main surface 2b side are equal. The thickness direction of the weight-bearing part 242 is the same as the thickness direction of the arm part 241. In the illustration, the center plane in the thickness direction of the weight-bearing part 242 and the center plane CP in the thickness direction of the arm part 241 are located on the same surface. Furthermore, step 245 is defined in the same way as step 244.

[0124] Furthermore, the steps 244 and 245 provided on the second main surface 2b are configured to include inclined surfaces, and when viewed in a plane from the thickness direction of the weighting portion 242, the weighting portion 242 has a portion whose thickness gradually decreases between the first portion 242a and the second portions 242b and 242c. Therefore, the weighting film 33 can be easily and continuously formed across the first portion 242a and the second portions 242b and 242c. Furthermore, cracks in the weighting film 33 caused by the steps 244 and 245 between the first portion 242a and the second portions 242b and 242c can be reduced. Moreover, the weighting portions 252, 262, and 272 are also configured in the same way as the weighting portion 242, achieving the same effect.

[0125] In this embodiment, the second portions 242b and 242c are disposed on both sides of the drive arm 24 (vibrating arm) in the width direction relative to the first portion 242a. This reduces the mass at both ends of the weight-applying portion 242 in the width direction, thereby reducing the torsional torque of the drive arm 24. Furthermore, the weight-applying portions 252, 262, and 272 are also configured in the same way as the weight-applying portion 242, achieving the same effect.

[0126] Furthermore, the first main surface 2a of the weight-applying portion 242 is a flat surface. Therefore, it is unnecessary to machine the first main surface 2a side of the weight-applying portion 242 to form the first portion 242a and the second portions 242b and 242c on the weight-applying portion 242, resulting in a simplified manufacturing process for the vibrating element 1. Furthermore, the weight-applying portions 252, 262, and 272 are also constructed in the same manner as the weight-applying portion 242, achieving the same effect. Additionally, the first main surface 2a can have steps like the second main surface 2b, but since it is positioned at the center of gravity G1 as described above, the depth of the steps on the first main surface 2a is preferably shallower than the depth of the steps on the second main surface 2b.

[0127] The weight-applying membrane 33 is disposed on the first part 242a and the second parts 242b and 242c. This increases the mass of the weight-applying membrane 33. Furthermore, it simplifies the formation of the weight-applying membrane 33. Additionally, weight-applying membranes 34, 35, and 36 are also constructed in the same manner as the weight-applying membrane 33, achieving the same effect. Furthermore, if the center of gravity G2 is located as described above, the weight-applying membrane 33 can be disposed on only one of the first part 242a and the second parts 242b and 242c. Here, when the weight-applying membrane 33 is disposed only on the first part 242a, compared to when it is disposed only on the second parts 242b and 242c, there is an advantage in that it is easier to achieve mass balance of the drive arm 24 in the width direction.

[0128] Furthermore, while the thickness of the weighting film 33 is uniform in the illustration, it can also have multiple portions with varying thicknesses. That is, the weighting film 33 can also have a first weighting film and a second weighting film with a thickness thinner than the first weighting film. In this case, fine-tuning and coarse-tuning can be easily performed when adjusting the resonant frequency of the drive arm 24 by removing a portion of the weighting film 33 using energy lines such as lasers. Here, the thicker first weighting film has a larger mass per unit area, making it suitable for coarse-tuning (coarse adjustment) of the resonant frequency of the drive arm 24. On the other hand, the thinner second weighting film has a smaller mass per unit area, making it suitable for fine-tuning (fine-tuning) of the resonant frequency of the drive arm 24. Furthermore, weighting films 34, 35, and 36 are also constructed in the same way as weighting film 33, thereby achieving the same effect.

[0129] Furthermore, in this embodiment, the driving arms 24, 25, 26, and 27 are described in such a way that the center of gravity of the entire structure composed of the weighting portions 242, 252, 262, and 272 and the weighting membranes 33, 34, 35, and 36 is close to the center C of the driving arms 24, 25, 26, and 27. However, the detection arms 22 and 23 can also be constructed in the same way as the driving arms 24, 25, 26, and 27. In this case, the center planes in the thickness direction of the arms 221 and 231 are defined in the same way as the center plane in the thickness direction of the arm 241. The weighting membranes 31 and 32 are defined in the same way as the weighting membrane 33.

[0130] (Manufacturing method of vibrating element)

[0131] Hereinafter, the manufacturing method of the vibration element of the present invention will be described using the manufacturing of the above-described vibration element 1 as an example.

[0132] Figure 6 This is a flowchart illustrating an example of a method for manufacturing a vibrating element. For example... Figure 6 As shown, the manufacturing method of the vibrating element 1 includes a vibrating plate forming step S10, an electrode forming step S20, a weighting film forming step S30, and a frequency adjustment step S40. Each step will be described in turn below.

[0133] -Vibration plate forming process S10-

[0134] Figure 7 This is a cross-sectional view showing the process of preparing the substrate in the vibrating plate forming process. Figure 8 This is a cross-sectional view showing the process of forming a corrosion-resistant film and a photoresist film in the vibrating plate forming process. Figure 9 This is a cross-sectional view showing the process of forming the shape of the vibrating plate in the vibrating plate forming process. Figure 10 This is a cross-sectional view showing a process in which a portion of the corrosion-resistant film is removed during the vibrating plate forming process. Figure 11 This is a cross-sectional view showing the process of forming the groove in the vibrating plate forming process. Figure 12 This is a cross-sectional view showing the process of removing the corrosion-resistant film and the photoresist film during the vibratory plate formation process. Additionally, Figures 7 to 12 It shows the corresponding Figure 5 The cross section.

[0135] First, a vibrating plate 2 is formed. Specifically, for example, firstly, as... Figure 7 As shown, a quartz substrate 20 is prepared, which has a first main surface 2a and a second main surface 2b. Then, as... Figure 8 As shown, corrosion-resistant films 51 and 52 and photoresist films 53 and 54 are sequentially formed on both sides of the quartz substrate 20. Here, corrosion-resistant films 51 and 52 are, for example, laminated films obtained by sequentially layering chromium and gold using methods such as vapor deposition and sputtering, respectively. They are resistant to the etching solutions used in the shape forming process and the trench forming process described later, and are patterned corresponding to the planar shape (outer shape) of the vibrating plate 2. Furthermore, photoresist films 53 and 54 are films made of photoresist material, and are resistant to the etching solutions used in the shape forming process and the trench forming process described later. They are patterned not only corresponding to the planar shape (outer shape) of the vibrating plate 2, but also to the planar shapes of the trench 243 and the second parts 242b and 242c, etc., through exposure and development.

[0136] Next, as Figure 9As shown, the quartz substrate 20 is etched using corrosion-resistant films 51 and 52 and resist films 53 and 54 as masks to obtain a quartz substrate 20A with the same shape as the vibrating plate 2 (shape forming process). Then, as... Figure 10 As shown, a corrosion-resistant film 52A is obtained by etching the corrosion-resistant film 52 using the resist film 54 as a mask. Furthermore, as... Figure 11 As shown, the quartz substrate 20A is etched using corrosion-resistant films 51 and 52A and resist films 53 and 54 as masks, as follows: Figure 12 As shown, the corrosion-resistant films 51 and 52A and the resist films 53 and 54 are removed by etching, thereby obtaining the vibrating plate 2 (groove formation process).

[0137] Here, the vibrating element 2 can also be connected to other parts of the quartz substrate 20A (hereinafter also referred to as "wafer state"). In the wafer state, the vibrating element 2 is connected to other parts of the quartz substrate 20A, for example, via a broken portion, wherein at least one of the width and thickness of the broken portion is small and fragile. Furthermore, in the wafer state, multiple vibrating elements 1 can be formed simultaneously on the quartz substrate 20A.

[0138] -Electrode forming process S20-

[0139] Figure 13 This is a cross-sectional view showing the electrode forming process.

[0140] like Figure 13 As shown, electrode film 4 is formed. More specifically, a metal film is uniformly formed on the surface of the vibrating plate 2, for example, by sputtering. Furthermore, after obtaining a photoresist mask by exposure and development through coating with photoresist, the portion of the metal film exposed from the photoresist mask is removed using an etchant. Thus, electrode film 4 is formed.

[0141] -Weighted film formation process S30-

[0142] Figure 14 This is a cross-sectional view showing the weighted film formation process.

[0143] like Figure 14 As shown, a weighted film 3 is formed by mask evaporation or other methods.

[0144] -Frequency adjustment process S40-

[0145] Figure 15 This is a cross-sectional view showing the frequency adjustment process.

[0146] like Figure 15As shown, a portion of the weighting membrane 3 is removed using the energy line LL as needed. More specifically, a portion of the weighting membranes 33-36 is removed as needed to make the resonant frequencies of the drive arms 24-27 equal to each other, thereby adjusting the frequency of the drive vibration (the resonant frequencies of the drive arms 24-27). In addition, a portion of the weighting membranes 31 and 32 is removed as needed to adjust the frequency of the detection vibration (the resonant frequencies of the detection arms 22 and 23).

[0147] As an energy line LL, for example, pulsed lasers such as YAG, YVO4, and excimer lasers, continuous oscillating lasers such as carbon dioxide gas lasers, FIB (Focused Ion Beam), IBF (Ion Beam Figuring), etc. can be used.

[0148] This frequency adjustment process S40 can be performed in the wafer state or in the state of being mounted in the package 11 described later. In addition, the frequency adjustment process S40 can also be performed in multiple steps. For example, coarse adjustment can be performed in the wafer state as the first adjustment, and fine adjustment can be performed in the state of being mounted in the package 11 as the second adjustment.

[0149] As described above, the manufacturing method of the vibrating element 1 includes the following steps: a step of forming a base 21 and a drive arm 24 (vibrating arm) (vibrating plate forming step S10), the drive arm 24 (vibrating arm) extending from the base 21 and having a first main surface 2a and a second main surface 2b that are opposite in orientation in the thickness direction of the vibrating element 1, the center of gravity G1 of the drive arm 24 being closer to the first main surface 2a than the center surface of the drive arm 24 in the thickness direction; a step of forming a weighting film 33 on the drive arm 24 (weighting film forming step S30), the center of gravity G2 of the weighting film 33 being closer to the second main surface 2b than the center surface of the drive arm 24 in the thickness direction; and a step of adjusting the resonant frequency of the drive arm 24 by adjusting the mass of the weighting film 33 (frequency adjustment step S40). According to such a manufacturing method of the vibrating element 1, the characteristics of the obtained vibrating element 1 can be improved. Here, the "center plane in the thickness direction of the drive arm 24" is a plane perpendicular to the thickness direction of the drive arm 24, and it is a plane whose distances in the thickness direction on the first main surface 2a side and the thickness direction on the second main surface 2b side are equal. Furthermore, in this embodiment, the example described is the case where the mass of the weighting film 33 is reduced by removing a portion of the weighting film 33 using energy lines LL. However, the mass of the weighting film 33 can also be increased by forming a film on the weighting film 33 using a film deposition method such as sputtering. The same applies to the resonant frequencies of the other drive arms 25-27 and the detection arms 22 and 23.

[0150] <Second Implementation Method>

[0151] Figure 16 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the second embodiment of the present invention. Figure 17 It is along Figure 16 A cross-sectional view of the CC line.

[0152] The second embodiment will be described below, focusing on its differences from the embodiment described above, omitting descriptions of identical items. Furthermore, in Figure 16 and Figure 17 In this document, structures identical to those described in the above embodiments are labeled with the same reference numerals. Furthermore, one drive arm will be described representatively below, but the same applies to other drive arms.

[0153] This embodiment is the same as the first embodiment described above, except that the structure (shape) of the weight-bearing part is different.

[0154] like Figure 16 As shown, the vibration element 1A of this embodiment has a weight-bearing portion 242A of a drive arm 24A, which has: a first portion 242d connected to the arm portion 241; and a second portion 242e disposed on the side opposite to the arm portion 241 relative to the first portion 242d. Furthermore, as... Figure 17 As shown, the thickness t2 of the second part 242e is thinner than the thickness t1 of the first part 242d. Here, the weighted membrane 33 is disposed across the first part 242d and the second part 242e.

[0155] According to this embodiment, similar to the first embodiment described above, the characteristics can also be improved.

[0156] Furthermore, in this embodiment, the second portion 242e is positioned on the side opposite to the base 21 relative to the first portion 242d. Therefore, the second portion 242e is located at the end of the drive arm 24A, where the mass effect is large, thus reducing the area of ​​the second portion 242e when viewed in planar view. Additionally, it has the advantage that the mass of the weight-applying portion 242A is less likely to become unbalanced in the width direction.

[0157] <Third Implementation Method>

[0158] Figure 18 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the third embodiment of the present invention.

[0159] The third embodiment will be described below, focusing on its differences from the embodiments described above, omitting descriptions of identical items. Furthermore, in Figure 18In this document, structures identical to those described in the above embodiments are labeled with the same reference numerals. Furthermore, one drive arm will be described representatively below, but the same applies to other drive arms.

[0160] This embodiment is the same as the first embodiment described above, except that the structure (shape) of the weight-bearing part is different.

[0161] The vibration element 1B of this embodiment has a weight-bearing portion 242B of the drive arm 24B that combines the first and second embodiments described above. That is, as... Figure 18 As shown, the weighting portion 242B has: a first portion 242f, which is connected to the arm portion 241; and a second portion 242g, which is located on both sides and the end side of the first portion 242f in the width direction. Furthermore, the thickness of the second portion 242g is thinner than the thickness of the first portion 242f. Here, the weighting membrane 33 is disposed across the first portion 242f and the second portion 242g.

[0162] According to this embodiment, similar to the first embodiment described above, the characteristics can also be improved.

[0163] <Fourth Implementation>

[0164] Figure 19 This is an enlarged plan view showing the weight-applying portion and the weight-applying membrane of the vibrating arm (driving arm) of the vibrating element according to the fourth embodiment of the present invention. Figure 20 It is along Figure 19 A cross-sectional view of the BB line.

[0165] The fourth embodiment will be described below, focusing on its differences from the embodiments described above, omitting descriptions of identical items. Furthermore, in Figure 19 and Figure 20 In this document, structures identical to those described in the above embodiments are labeled with the same reference numerals. Furthermore, one drive arm will be described representatively below, but the same applies to other drive arms.

[0166] This embodiment is the same as the first embodiment described above, except that the structure (shape) of the weight-bearing part is different.

[0167] like Figure 19 As shown, the vibration element 1C of this embodiment has a weight-bearing portion 242C of the drive arm 24C, which includes: a frame-shaped first portion 242i connected to the arm portion 241; and a second portion 242h located inside the first portion 242i. Furthermore, as... Figure 20 As shown, the thickness t2 of the second part 242h is thinner than the thickness t1 of the first part 242i. Here, the weighting membrane 33 is disposed across the first part 242i and the second part 242h in the width direction of the weighting portion 242C.

[0168] According to this embodiment, similar to the first embodiment described above, the characteristics can also be improved.

[0169] Furthermore, in this embodiment, when viewed in a plane along the thickness direction of the weighting portion 242C, the first portion 242i is configured to surround the second portion 242h. This second portion 242h is provided by forming a recess 247. Similar to the groove 243 described above, the recess 247 can also be formed by etching. Therefore, the design of the second portion 242h becomes easier.

[0170] <Fifth Implementation>

[0171] Figure 21 This is a plan view showing the vibration element according to the fifth embodiment of the present invention.

[0172] The fifth embodiment will be described below, but the description will focus on the differences from the embodiments described above, and the description of the same items will be omitted.

[0173] This embodiment is the same as the first embodiment described above, except that the invention is applied to a so-called H-type vibrating element.

[0174] Figure 21 The vibration element 1D shown is a sensor element for detecting angular velocity about the y-axis. The vibration element 1D has a vibrating plate 2D, and an electrode film (not shown) and a weighting film 3D disposed on the vibrating plate 2D.

[0175] The vibrating plate 2D has a base 21D, a pair of drive arms 24D and 25D, and a pair of detection arms 22D and 23D. They are integrally formed using a Z-cut quartz plate. Furthermore, the correspondence between the crystal axis of the quartz and the x-axis, y-axis, and z-axis is the same as in the first embodiment described above.

[0176] The base 21D is supported on the package 11, which will be described later.

[0177] Drive arms 24D and 25D extend from the base 21D in the y-axis direction (+y direction). Drive arms 24D and 25D are configured similarly to the drive arms in any of the first to fourth embodiments described above. Although not shown, similar to drive arms 24 to 27 in the first embodiment, each drive arm 24D and 25D is provided with a pair of drive electrodes (drive signal electrode and drive ground electrode). These drive electrodes, when energized, cause drive arms 24B and 26B to bend and vibrate in the x-axis direction. These drive electrodes are electrically connected to terminals (not shown) on the base 21D via wiring (not shown).

[0178] Detection arms 22D and 23D extend from the base 21D in the y-axis direction (-y direction). Although not shown, a pair of detection electrodes (a detection signal electrode and a detection ground electrode) are provided on the detection arms 22D and 23D, which detect the charge generated by the bending vibration of the detection arms 22D and 23D in the z-axis direction. The pair of detection electrodes are electrically connected to terminals (not shown) on the base 21D via wiring (not shown).

[0179] The weighting membrane 3D includes: weighting membranes 31D and 32D, which are disposed on the end portions (weighting portions) of the detection arms 22D and 23D; and weighting membranes 33D and 34D, which are disposed on the end portions (weighting portions) of the drive arms 24D and 25D.

[0180] In this type of vibrating element 1D, by applying a driving signal between a pair of driving electrodes, such as Figure 21 As shown by arrows A1 and A2, drive arm 24D and drive arm 25D undergo bending vibration (drive vibration) by repeatedly approaching and separating each other.

[0181] Under the state of driving vibration of drive arms 24D and 25D, when an angular velocity ω about the y-axis is applied to the vibrating element 1D, drive arms 24D and 25D experience Coriolis force, such as Figure 21 As indicated by arrows B1 and B2, they undergo bending vibrations in opposite directions along the z-axis. Meanwhile, as... Figure 21 As indicated by arrows C1 and C2, the detection arms 22D and 23D bend and vibrate in opposite directions along the z-axis (vibration detection).

[0182] Then, a charge generated between the pair of detection electrodes by the bending vibration of such detection arms 22D and 23D is output from the pair of detection electrodes. The angular velocity ω applied to the vibrating element 1D can be determined from such charge.

[0183] According to this embodiment, similar to the first embodiment described above, the characteristics can also be improved.

[0184] Here, the vibration element 1D of this embodiment includes: drive arms 24D and 25D, which extend from the base 21D and drive vibration; and detection arms 22D and 23D, which extend from the base 21D in the opposite direction to the drive arms 24D and 25D and deform in response to inertial force. The drive arms 24D and 25D are vibration arms. Thus, the characteristics of the so-called H-type vibration element 1D can be improved.

[0185] <Sixth Implementation>

[0186] Figure 22This is a plan view showing the vibration element according to the sixth embodiment of the present invention.

[0187] The sixth embodiment will be described below, but the description will focus on the differences from the above embodiments, and the description of the same items will be omitted.

[0188] This embodiment is the same as the first embodiment described above, except that the invention is applied to a so-called two-legged tuning fork type vibrating element.

[0189] Figure 22 The vibration element 1E shown is a sensor element for detecting angular velocity about the y-axis. The vibration element 1E has a vibrating plate 2E, and an electrode diaphragm (not shown) and a weighting diaphragm 33E and 34E disposed on the vibrating plate 2E.

[0190] The vibrating plate 2E has a base 21E and a pair of vibrating arms 24E and 25E, which are integrally formed using a Z-cut quartz plate. Furthermore, the correspondence between the crystal axis of the quartz and the x-axis, y-axis, and z-axis is the same as in the first embodiment described above.

[0191] The base 21E includes: a first base 214 connected to the vibrating arms 24E and 25E; a second base 216 disposed opposite to the first base 214 on the opposite side of the vibrating arms 24E and 25E; and a connecting portion 215 connecting the first base 214 and the second base 216. The connecting portion 215 is located between the first base 214 and the second base 216, and its width (length in the x-axis direction) is smaller than that of the first base 214. This reduces the length of the base 21E along the y-axis and decreases vibration leakage. Here, the second base 216 is supported, for example, on the package 11 described later.

[0192] Vibration arms 24E and 25E extend from the base 21E in the y-axis direction (+y direction). Vibration arms 24E and 25E are configured similarly to the drive arms in any of the first to fourth embodiments described above. Although not shown, similar to the drive arms 24 to 27 of the first embodiment, each vibration arm 24E and 25E is provided with a pair of drive electrodes (drive signal electrode and drive ground electrode). These drive electrodes, when energized, cause the drive arms 24E and 25E to bend and vibrate in the x-axis direction. These drive electrodes are electrically connected to terminals (not shown) on the base 21E via wiring (not shown).

[0193] In addition, although not shown, besides the aforementioned pair of drive electrodes, the vibrating arms 24E and 25E are also provided with a pair of detection electrodes (detection signal electrode and detection ground electrode). These detection electrodes detect the charge generated by the bending vibration of the vibrating arms 24E and 25E in the z-axis direction. These detection electrodes are electrically connected to terminals (not shown) on the base 21E via wiring (not shown).

[0194] The weighting membranes 33E and 34E are mounted on the ends (weighting parts) of the vibrating arms 24E and 25E.

[0195] In the vibrating element 1E configured in this way, by applying a driving signal between a pair of driving electrodes, the vibrating arm 24E and the vibrating arm 25E perform bending vibration (driving vibration) in a manner that repeatedly approaches and separates from each other.

[0196] When the vibrating arms 24E and 25E are driven to vibrate, and an angular velocity ω about the y-axis is applied to the vibrating element 1E, the Coriolis force excites vibrations in the vibrating arms 24E and 25E, causing them to bend towards each other in the z-axis direction. Then, a charge generated between the pair of detection electrodes due to this excitation vibration is output from the pair of detection electrodes. The angular velocity ω applied to the vibrating element 1E can be determined from this charge.

[0197] According to this embodiment, similar to the first embodiment described above, the characteristics can also be improved.

[0198] 2. Physical quantity sensors

[0199] Figure 23 This is a cross-sectional view illustrating a physical quantity sensor according to an embodiment of the present invention.

[0200] Figure 23 The physical quantity sensor 10 shown is a vibrating gyroscope sensor that detects the angular velocity about the x-axis, y-axis, or z-axis. The physical quantity sensor 10 has a vibrating element 1 (or 1A, 1B, 1C, 1D, 1E), a support component 12, a circuit element 13 (integrated circuit chip), and a package 11 that houses them.

[0201] The package 11 has: a box-shaped base 111 having a recess for receiving the vibrating element 1; and a plate-shaped cover 112, which is engaged with the base 111 via a coupling member 113 in a manner that seals the opening of the recess of the base 111. The package 11 can be in a depressurized (vacuum) state, or it can be sealed with an inert gas such as nitrogen, helium, or argon.

[0202] The recess of the base 111 has: an upper surface located on the opening side; a lower surface located on the bottom side; and a middle surface located between the upper and lower surfaces. The material of the base 111 is not particularly limited, but various ceramics such as alumina and various glass materials can be used. Furthermore, the material of the cover 112 is not particularly limited, but any component with a coefficient of linear expansion similar to that of the base 111 can be used. For example, if the base 111 is made of a ceramic as described above, it is preferable to make the cover 112 of an alloy such as an iron-nickel-cobalt alloy. In this embodiment, a seam ring is used as the joining member 113, but the joining member 113 can also be constructed using, for example, low-melting-point glass, adhesives, etc.

[0203] Multiple connection terminals 14 and 15 are respectively provided on the upper and middle sections of the recessed portion of the base 111. A portion of the multiple connection terminals 15 provided on the middle section is electrically connected to a terminal 16 provided on the bottom surface of the base 111 via a wiring layer (not shown) provided on the base 111, and the remaining portion is electrically connected to the multiple connection terminals 14 provided on the upper section via wiring (not shown). These connection terminals 14 and 15 are not particularly limited as long as they are conductive, and for example, they can be made of a metal cover film, which is formed by stacking various cover films such as Ni (nickel), Au (gold), Ag (silver), Cu (copper), etc. on a metallization layer (base layer) of Cr (chromium), W (tungsten), etc.

[0204] The circuit element 13 is fixed to the lower surface of the recess in the base 111 using an adhesive 19 or similar agent. For example, epoxy, silicone, or polyimide adhesives can be used as the adhesive 19. The circuit element 13 has a plurality of terminals (not shown), each of which is electrically connected to a connection terminal 15 disposed on the aforementioned middle surface via a conductive wire. The circuit element 13 includes a drive circuit for driving the vibrating element 1 to vibrate, and a detection circuit for detecting the vibration generated on the vibrating element 1 when an angular velocity is applied.

[0205] Furthermore, the support member 12 is connected to a plurality of connecting terminals 14 provided on the upper surface of the recess of the base 111 via a conductive adhesive 17. The support member 12 has: a wiring pattern 122 connected to the conductive adhesive 17; and a support substrate 121 supporting the wiring pattern 122. As the conductive adhesive 17, conductive adhesives such as epoxy, silicone, and polyimide adhesives mixed with conductive substances such as metal fillers can be used, for example.

[0206] The support substrate 121 has an opening in the center, and a plurality of elongated leads of the wiring pattern 122 extend within the opening. The vibrating element 1 is connected to the ends of these leads via conductive bumps 123.

[0207] In addition, in this embodiment, the circuit element 13 is disposed inside the package 11, but the circuit element 13 may also be disposed outside the package 11.

[0208] As described above, the physical quantity sensor 10 includes a vibrating element 1 (or 1A, 1B, 1C, 1D, 1E) and a package 11 that houses the vibrating element 1 (or 1A, 1B, 1C, 1D, 1E). With such a physical quantity sensor 10, the sensor characteristics (e.g., detection accuracy) of the physical quantity sensor 10 can be improved by utilizing the superior characteristics of the vibrating element 1 (or 1A, 1B, 1C, 1D, 1E).

[0209] 3. Inertial measurement device

[0210] Figure 24 This is an exploded perspective view showing an embodiment of the inertial measuring device of the present invention. Figure 25 yes Figure 24 The diagram shows a three-dimensional view of the substrate of the inertial measurement device.

[0211] Figure 24 The inertial measurement unit (IMU) 2000 shown is a so-called 6-axis motion sensor, which is used, for example, to install on a moving body (the object of measurement) such as a car or a robot, to detect the posture and behavior (inertial motion) of the moving body.

[0212] The inertial measurement device 2000 has a housing 2100, a connecting member 2200 and a sensor module 2300, the sensor module 2300 being fitted (inserted) into the housing 2100 with the connecting member 2200 in between.

[0213] The outer casing 2100 is box-shaped, and threaded holes 2110 are provided at two opposite corners of the outer casing 2100. The threaded holes 2110 are used to thread the object to be measured.

[0214] The sensor module 2300 has an inner shell 2310 and a substrate 2320. The inner shell 2310 is housed inside the outer shell 2100 while supporting the substrate 2320. Here, the inner shell 2310 is joined to the outer shell 2100 via a joining member 2200 (e.g., a rubber gasket) using an adhesive or the like. Furthermore, the inner shell 2310 has a recess 2311, which functions as a storage space for components mounted on the substrate 2320; and an opening 2312, which exposes a connector 2330 provided on the substrate 2320 to the outside. The substrate 2320 is, for example, a multilayer wiring substrate, and is joined to the inner shell 2310 using an adhesive or the like.

[0215] like Figure 25As shown, a connector 2330, angular velocity sensors 2340X, 2340Y, and 2340Z, an acceleration sensor 2350, and a control IC 2360 are mounted on the substrate 2320.

[0216] Connector 2330 is used for electrical connection with an external device (not shown) to transmit and receive electrical signals such as power and measurement data between the external device and the inertial measurement device 2000.

[0217] Angular velocity sensor 2340X detects the angular velocity about the X-axis, angular velocity sensor 2340Y detects the angular velocity about the Y-axis, and angular velocity sensor 2340Z detects the angular velocity about the Z-axis. Here, angular velocity sensors 2340X, 2340Y, and 2340Z are the physical quantity sensors 10 mentioned above. Furthermore, accelerometer 2350 is, for example, an accelerometer formed using MEMS technology, detecting acceleration in each of the X, Y, and Z axis directions.

[0218] The control IC 2360 is a Microcontroller Unit (MCU) that integrates a storage unit including non-volatile memory, an A / D converter, etc., and controls various parts of the inertial measurement device 2000. The storage unit contains programs that define the order and content for detecting acceleration and angular velocity, programs that digitize the detected data and assemble it into grouped data, and supplementary data.

[0219] As described above, the inertial measurement device 2000 includes a physical quantity sensor 10 and a control IC 2360, which is electrically connected to the physical quantity sensor 10. With such an inertial measurement device 2000, the characteristics of the inertial measurement device 2000 (e.g., measurement accuracy) can be improved by utilizing the excellent sensor characteristics of the physical quantity sensor 10.

[0220] 4. Electronic devices

[0221] Figure 26 This is a perspective view showing an embodiment of the electronic device of the present invention (a mobile (or notebook) personal computer).

[0222] In this figure, the personal computer 1100 consists of a main body 1104 with a keyboard 1102 and a display unit 1106 with a display unit 1108. The display unit 1106 is rotatably supported on the main body 1104 via a hinge structure. This personal computer 1100 incorporates an inertial measurement device 2000 that includes the aforementioned vibration elements 1 (or 1A, 1B, 1C, 1D, 1E).

[0223] Figure 27This is a plan view illustrating an embodiment (mobile phone) of the electronic device of the present invention.

[0224] In this figure, the mobile phone 1200 has an antenna (not shown), multiple operation buttons 1202, a receiver 1204, and a call port 1206. A display unit 1208 is arranged between the operation buttons 1202 and the receiver 1204. This mobile phone 1200 has a built-in inertial measurement device 2000 containing the aforementioned vibration element 1 (or 1A, 1B, 1C, 1D, 1E).

[0225] Figure 28 This is a perspective view illustrating an embodiment of the electronic device of the present invention (digital still camera).

[0226] A display unit 1310 is provided on the back of the housing 1302 in the digital still camera 1300. This display unit is configured to display the image signal from the CCD and functions as a viewfinder that displays the subject as an electronic image. Furthermore, a light-receiving unit 1304, including an optical lens (camera optical system) and a CCD, is provided on the front side (back side in the figure) of the housing 1302. When the photographer confirms the image of the subject displayed on the display unit 1310 and presses the shutter button 1306, the image signal from the CCD at that moment is transmitted to the memory 1308 for storage. This digital still camera 1300 incorporates an inertial measurement device 2000 that includes the aforementioned vibration elements 1 (or 1A, 1B, 1C, 1D, 1E). The measurement results of this inertial measurement device 2000 are used, for example, for shake correction.

[0227] Such an electronic device has a vibrating element 1 (or 1A, 1B, 1C, 1D, 1E). According to such an electronic device, the characteristics of the electronic device (e.g., reliability) can be improved by utilizing the superior characteristics of the vibrating element 1 (or 1A, 1B, 1C, 1D, 1E).

[0228] In addition, the electronic device of the present invention, besides Figure 26 Personal computers Figure 27 mobile phones, Figure 28Besides digital still cameras, it can also be applied to smartphones, tablets, watches (including smartwatches), inkjet printers, wearable devices such as HMDs (head-mounted displays), laptops, televisions, cameras, video recorders, car navigation systems, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, video game devices, word processors, workstations, video phones, anti-theft television monitors, electronic binoculars, POS terminals, medical devices (such as electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiogram measuring devices, ultrasound diagnostic devices, and electronic endoscopes), fish detectors, various measuring devices, measuring instruments (such as measuring instruments for vehicles, airplanes, and ships), base stations for portable terminals, flight simulators, etc.

[0229] 5. Moving objects

[0230] Figure 29 This is a perspective view showing an embodiment (automobile) of the mobile body of the present invention.

[0231] The vehicle 1500 has an inertial measurement device 2000 built into it, which includes the aforementioned vibration elements 1 (or 1A, 1B, 1C, 1D, 1E). For example, the inertial measurement device 2000 can detect the attitude of the vehicle body 1501. The detection signal from the inertial measurement device 2000 is provided to the vehicle attitude control device 1502. The vehicle attitude control device 1502 can detect the attitude of the vehicle body 1501 based on the signal, and control the stiffness of the suspension and the braking of each wheel 1503 accordingly.

[0232] Furthermore, such posture control can be used for bipedal walking robots or radio-controlled helicopters (including drones). As described above, an inertial measurement unit 2000 is assembled to achieve posture control of various moving bodies.

[0233] As described above, the automobile 1500, as a moving body, has a vibration element 1 (or 1A, 1B, 1C, 1D, 1E). According to such an automobile 1500, the characteristics (e.g., reliability) of the automobile 1500 can be improved by utilizing the superior characteristics of the vibration element 1 (or 1A, 1B, 1C, 1D, 1E).

[0234] The vibration element, the method for manufacturing the vibration element, the physical quantity sensor, the inertial measurement device, the electronic device, and the moving body of the present invention have been described above with reference to the illustrated embodiments. However, the present invention is not limited thereto, and the structure of each part can be replaced with any structure having the same function. In addition, other arbitrary structures can be added to the present invention.

[0235] Furthermore, in the above embodiments, the vibrating element is formed in the shape of a so-called double T-type, H-type, or double-legged tuning fork, but it is not limited to any element that has a vibrating arm that vibrates in the in-plane direction. For example, it can also be a three-legged tuning fork, orthogonal type, prism type, or various other types.

[0236] The entire disclosure of Japanese Patent Application No. 2018-009173, filed on January 23, 2018, is hereby clearly incorporated by reference.

Claims

1. A vibrating element, characterized in that, When the three mutually perpendicular axes are designated as the x-axis, y-axis, and z-axis, the vibrating element comprises: base; and A vibrating arm that extends from the base in a direction along the y-axis. The vibrating arm comprises: The arm portion, which is located on the base side; The weight-bearing portion, which is located further to the end of the arm, includes a first principal surface and a second principal surface that are opposite to each other along the z-axis direction; and A weight-applying membrane is disposed on the second main surface side of the weight-applying portion. The weight-applying part includes: Part 1; and Part 2 is thinner than Part 1 in the z-axis direction. When viewed in section along the y-axis, the second portion is positioned on either side of the first portion. The center of gravity of the weight-bearing part is closer to the first main surface than the center plane of the arm in the z-axis direction. The center of gravity of the weight-bearing membrane is closer to the second main surface than the center surface. The weight-applying membrane comprises: A first weighting film, disposed on the second main surface of the first portion; and The second weighting film is disposed on the second main surface of the second part. The height from the center plane to the surface of the first weighting film is greater than the height from the center plane to the surface of the second weighting film.

2. The vibration element according to claim 1, characterized in that, The first principal surface is flat.

3. The vibration element according to claim 1, characterized in that, The weighting membrane is disposed at the portion of the second main surface where the thickness in the z-axis direction of the weighting portion is the greatest.

4. The vibration element according to claim 1, characterized in that, The second part is positioned on the opposite side of the arm relative to the first part.

5. A vibrating element, characterized in that, When the three mutually perpendicular axes are designated as the x-axis, y-axis, and z-axis, the vibrating element comprises: base; and A vibrating arm that extends from the base in a direction along the y-axis. The vibrating arm comprises: The arm portion, which is located on the base side; The weight-bearing portion, which is located further to the end of the arm, includes a first principal surface and a second principal surface that are opposite to each other along the z-axis direction; and A weight-applying membrane is disposed on the second main surface side of the weight-applying portion. The weight-applying part includes: Part 1; and Part 2 is thinner than Part 1 in the z-axis direction. When viewed in section along the y-axis, the first portion is positioned on either side of the second portion. The center of gravity of the weight-bearing part is closer to the first main surface than the center plane of the arm in the z-axis direction. The center of gravity of the weight-bearing membrane is closer to the second main surface than the center surface. The weight-applying membrane comprises: A first weighting film, disposed on the second main surface of the first portion; and The second weighting film is disposed on the second main surface of the second part. The height from the center plane to the surface of the first weighting film is greater than the height from the center plane to the surface of the second weighting film.

6. The vibration element according to claim 5, characterized in that, When the weight-applying part is viewed from the z-axis direction... The first part is frame-shaped. The second part is disposed inside the frame-shaped first part.

7. The vibration element according to claim 5, characterized in that, The weighting membrane is disposed at the portion of the second main surface where the thickness in the z-axis direction of the weighting portion is the greatest.

8. The vibration element according to claim 5, characterized in that, The first part is positioned on the opposite side of the arm relative to the second part.

9. The vibration element according to claim 5, characterized in that, The first part is disposed on the arm side relative to the second part.

10. A vibrating element, characterized in that, When the three mutually perpendicular axes are designated as the x-axis, y-axis, and z-axis, the vibrating element comprises: base; and A vibrating arm that extends from the base in a direction along the y-axis. The vibrating arm comprises: The arm portion, which is located on the base side; A weight-applying section, located further to the end of the arm, comprising a first main surface and a second main surface that are opposite to each other along the z-axis; and A weight-applying membrane is disposed on the second main surface side of the weight-applying portion. The weight-applying part includes: Part 1; and Part 2 is thinner than Part 1 in the z-axis direction. The second part is positioned relative to the first part on the side opposite to the arm. The center of gravity of the weight-bearing part is closer to the first main surface than the center plane of the arm in the z-axis direction. The center of gravity of the weighted membrane is closer to the second main surface than the center surface.

11. The vibration element according to claim 10, characterized in that, When viewed from above along the z-axis The first part is connected to the arm. The second part is connected to the first part on the side opposite to the arm.

12. The vibration element according to claim 10, characterized in that, The weighting film includes a second weighting film disposed on the second main surface of the second portion.

13. The vibration element according to claim 10, characterized in that, The weighting film includes a first weighting film disposed on the second main surface of the first portion.

14. The vibration element according to claim 10, characterized in that, The weighting membrane is disposed at the portion of the second main surface where the thickness in the z-axis direction of the weighting portion is the greatest.

15. The vibration element according to any one of claims 1 to 14, characterized in that, The first main surface of the first part and the first main surface of the second part are located on the same plane.

16. The vibrating element according to any one of claims 1 to 14, characterized in that, The width of the weight-bearing part in the x-axis direction is greater than the width of the arm in the x-axis direction.

17. The vibration element according to any one of claims 1 to 14, characterized in that, The weight-bearing section includes a step formed by the first part and the second part.

18. The vibration element according to claim 17, characterized in that, The step includes a portion whose thickness gradually decreases in the z-axis direction.

19. The vibration element according to any one of claims 1 to 14, characterized in that, The arm portion is symmetrical about the central plane.

20. The vibration element according to any one of claims 1 to 14, characterized in that, An electrode diaphragm is disposed on the vibrating arm. The weighting membrane is disposed on the electrode membrane.

21. The vibration element according to any one of claims 1 to 14, characterized in that, The base includes: Base body; and The connecting portion extends from the base body. The vibrating element comprises: The drive arm, which serves as the vibrating arm, extends from the connecting portion; and The detection arm extends from the base body.

22. The vibration element according to any one of claims 1 to 14, characterized in that, The vibrating element comprises: The drive arm, which serves as the vibrating arm, extends from the base; and The detection arm extends from the base in the opposite direction to the drive arm.

23. A physical quantity sensor, characterized in that, The physical quantity sensor includes: The vibrating element according to any one of claims 1 to 22; and The enclosure houses the vibrating element.

24. An inertial measurement device, characterized in that, The inertial measurement device includes: The physical quantity sensor according to claim 23; and A microcontroller unit that controls the physical quantity sensor.

25. An electronic device, characterized in that, The electronic device comprises a vibration element as described in any one of claims 1 to 22.

26. A mobile body, characterized in that, The moving body comprises a vibrating element as described in any one of claims 1 to 22.

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