JP6281421B2 - Vibration type angular velocity sensor - Google Patents

Description

  The present invention relates to a vibration type angular velocity sensor.

  Conventionally, in Patent Document 1, a vibration type angular velocity sensor has been proposed. In this angular velocity sensor, when the drive vibration of the movable part provided in the angular velocity sensor and the detection vibration direction are on the xy plane, when unnecessary vibration in the z-axis direction occurs, the detection signal does not require unnecessary vibration. Since a signal is included, this is corrected. Specifically, a correction electrode is formed on the movable part, and a correction signal having a phase opposite to that of the detection signal included in the detection signal is extracted by the correction electrode and added to the detection signal so that the unnecessary signal is attenuated. I have to.

JP 2011-59040 A

  As described in Patent Document 1 described above, unnecessary vibrations vibrate in a direction other than the direction in which the movable part is originally intended to vibrate, and noise is added to the detection signal due to the unnecessary vibrations, so that the vibration-type angular velocity is increased. The detection accuracy of the sensor is lowered. As shown in Patent Document 1, even if the correction signal with the opposite phase is extracted by the correction electrode and the unnecessary signal can be attenuated from the detection signal, the unnecessary vibration cannot be suppressed, so the unnecessary vibration itself is suppressed. It is desirable to do.

  Conventionally, unnecessary vibrations have been made less likely to occur by improving the rigidity of the movable part or designing the frequency, but if the direction and magnitude of the unnecessary vibrations change, that is, if they have fluctuations. Can not respond.

  Therefore, the inventors have made a trial examination of a vibration type angular velocity sensor configured as follows as a vibration type angular velocity sensor capable of suppressing unnecessary vibration. In this vibration type angular velocity sensor, an xy direction is defined as one direction on the plane of the substrate on which the sensor structure is formed, a y-axis is defined as a direction perpendicular thereto, and a z-axis is defined as a normal direction relative to the plane of the substrate. It is configured on a plane and has a function of suppressing unnecessary vibration in the z-axis direction.

  For example, the semiconductor layer included in the substrate is patterned to form the fixed portion and the movable portion, and the sensor structure is formed by forming the beam portion including the detection beam and the drive beam that supports the movable portion. The vibration type angular velocity sensor is configured.

  Specifically, the detection beam is extended in the y-axis direction with the fixed portion as the center, and the drive weight and the detection weight serving as the movable weight and the detection weight are provided on both sides in the x-axis direction with the fixed portion interposed therebetween. The driving beam is extended in the y-axis direction around the driving and detection weight. The tip of the detection beam opposite to the fixed portion and the tip of the drive beam opposite to the drive / detection weight are connected by a support member, and a rectangular frame is formed by the drive beam, the support member, and the drive / detection weight. Make up body. The drive beam includes a drive unit that drives and vibrates the drive and detection weight in the x-axis direction together with the drive beam based on voltage application, and a control unit that suppresses unnecessary vibration in the z-axis direction based on voltage application. doing. Further, the detection beam is provided with a detection unit that detects the angular velocity by electrically extracting the displacement of the detection beam when the angular velocity is applied.

  In such a configuration, at the time of angular velocity detection, a driving voltage is applied to the driving unit to drive and vibrate the driving beams and driving / detecting weights located on both sides of the fixed unit in opposite directions. . When an angular velocity is applied in this state, a displacement vibration is generated that is displaced in the rotational direction around the fixed portion including movement in the y-axis direction on the xy plane. For this reason, it is possible to detect the angular velocity by displacing the detection beam and taking out the displacement as an electrical signal from the detection unit provided in the detection beam.

  In addition, when unnecessary vibration occurs in the z-axis direction, a voltage for suppressing unnecessary vibration is applied to the control unit to generate vibration having an opposite phase to the unnecessary vibration, thereby canceling the unnecessary vibration. Thereby, unnecessary vibration can be suppressed. In this way, unnecessary vibrations can be fed back and the control unit can be driven to cancel the unnecessary vibrations, so that even if the direction and magnitude of the unnecessary vibrations change, it is possible to respond to them. Become.

  However, in order to suppress unnecessary vibrations accurately in such a configuration, it is important to separate unnecessary vibrations generated in the z-axis direction from drive vibrations generated in the x-axis direction and detected vibrations generated in the x-axis and y-axis directions. It is. That is, it is necessary to separate the vibration axis so that the unnecessary vibration in the z-axis direction can be accurately detected.

  Here, in order to suppress unnecessary vibration, the case where the structure is provided with a control unit for the driving beam has been described as an example, but there are other forms for suppressing unnecessary vibration, and an angular velocity detection signal is provided. It is also possible to improve the accuracy of angular velocity detection by removing unnecessary vibration components. When any of these forms is applied, it is important to accurately detect unnecessary vibrations.

  The present invention has been made in view of the above points, and an object of the present invention is to separate the vibration axes generated in the vibration-type angular velocity sensor so as to accurately detect unnecessary vibrations.

  In order to achieve the above object, in the vibration type angular velocity sensor according to the first aspect of the present invention, a fixed portion (20, 100) fixed to the substrate (1) and a drive weight (31, 32, 122). And a movable portion (30, 120) having a detection weight (31, 32, 121) and a driving beam (42, 42) that supports the fixed weight while allowing the driving weight to move on a plane parallel to the plane of the substrate. 114) and a beam portion (40, 110) having a detection beam (41, 113) that supports the fixed portion while allowing the detection weight to move on a plane parallel to the plane of the substrate. The angular velocity is detected based on the fact that the weight is driven and vibrated in one direction on the plane of the substrate, and the detected weight vibrates in the direction perpendicular to the one direction on the plane of the substrate as the angular velocity is applied.

  In such a configuration, the drive units (51, 131) that drive and vibrate the drive weight, the detection elements (53, 133) that detect displacement of the detection beam accompanying application of the angular velocity, the vibration direction is the x-axis direction, the substrate X-axis vibration detection that detects vibration in the x-axis direction of the drive weight, with the vertical direction with respect to the x-axis direction on the plane parallel to the plane as the y-axis direction and the vertical direction with respect to the x-axis direction and the y-axis direction as the z-axis direction Unit (61, 65, 141, 145), y-axis vibration detection unit (62, 67, 142, 147) for detecting vibration in the y-axis direction of the driving weight, and vibration in the z-axis direction of the driving weight. and an unnecessary vibration detector (60, 140) including a z-axis vibration detector (63, 143).

  Thus, the unnecessary vibration detection part provided with the x-axis vibration detection part, the y-axis vibration detection part, and the z-axis vibration detection part is provided. In such a configuration, the vibration in the x-axis direction of the drive weight is detected by the x-axis vibration detection unit, the vibration in the y-axis direction is detected by the y-axis vibration detection unit, and the x-axis vibration is detected from the vibration in the z-axis direction. The vibration component in the z-axis direction generated based on the vibration in the direction and the y-axis direction can be removed. This makes it possible to extract unnecessary vibration components included in the vibration in the z-axis direction. Therefore, it is possible to accurately detect unnecessary vibration by separating the axis of vibration generated in the vibration type angular velocity sensor.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a top view of a vibration type angular velocity sensor concerning a 1st embodiment of the present invention. It is a perspective view of the vibration type angular velocity sensor shown in FIG. FIG. 3 is a sectional view taken along line III-III ′ in FIG. 1. FIG. 4 is a sectional view taken along line IV-IV ′ in FIG. 1. It is a detailed enlarged view of the area | region enclosed with the dashed-two dotted line in FIG. FIG. 6 is a sectional view taken along line VI-VI ′ in FIG. 5. It is the top view which showed the mode at the time of the drive vibration of the vibration type angular velocity sensor shown in FIG. It is the top view which showed the mode at the time of the angular velocity application of the vibration type angular velocity sensor shown in FIG. It is sectional drawing of the vibration type angular velocity sensor demonstrated in 2nd Embodiment. It is the figure which showed the manufacturing process of the vibration type angular velocity sensor shown in FIG. It is the figure which showed the manufacturing process of the vibration type angular velocity sensor following FIG. FIG. 12 is a diagram illustrating a manufacturing process of the vibration type angular velocity sensor subsequent to FIG. 11. It is a perspective view of a vibration type angular velocity sensor concerning a 3rd embodiment of the present invention. It is a detailed enlarged view of the area | region enclosed with the dashed-two dotted line in FIG. It is the enlarged view which showed an example of the structural example of the unnecessary vibration detection part 60 demonstrated by other embodiment. It is the enlarged view which showed an example of the structural example of the unnecessary vibration detection part 60 demonstrated by other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
A first embodiment of the present invention will be described. The vibration type angular velocity sensor (gyro sensor) described in the present embodiment is a sensor for detecting an angular velocity as a physical quantity, and is used for detecting a rotational angular velocity around a center line parallel to the vertical direction of the vehicle, for example. Further, the vibration type angular velocity sensor can be applied to other than the vehicle.

  Hereinafter, the vibration type angular velocity sensor according to the present embodiment will be described with reference to FIGS. In FIGS. 1 and 2, the drawings are simplified, but when a portion surrounded by a two-dot chain line in FIG. 1 is enlarged, the structure shown in FIG. 5 is obtained.

  The vibration type angular velocity sensor is mounted on the vehicle such that the xy plane in FIG. 1 is oriented in the horizontal direction of the vehicle and the z-axis direction coincides with the vertical direction of the vehicle. The vibration type angular velocity sensor is formed using a plate-like substrate 10. In the present embodiment, the substrate 10 is configured by an SOI (Silicon on insulator) substrate having a structure in which a buried oxide film 13 that is a sacrificial layer is sandwiched between a support substrate 11 and a semiconductor layer 12. One direction of the plane of the substrate 10 is the x-axis, the direction perpendicular to the x-axis on the plane is the y-axis, and the normal direction of the plane and the direction perpendicular to the x-axis and the y-axis are the z-axis. Is a plane parallel to the xy plane. A vibration type angular velocity sensor is configured using such a substrate 10 and, as shown in FIG. 2, for example, the buried oxide film 13 is partially removed after the semiconductor layer 12 side is etched into the pattern of the sensor structure. And it is comprised by releasing a part of sensor structure. Although the support substrate 11 is simplified in the drawing, it is actually configured as a flat plate. Although FIG. 2 is not a cross-sectional view, hatching is shown in the support substrate 11 and the buried oxide film 13 in order to make the drawing easy to see.

  The semiconductor layer 12 is patterned into the fixed portion 20, the movable portion 30 and the beam portion 40. As shown in FIG. 2, the fixed portion 20 has the buried oxide film 13 left at least on a part of the back surface thereof, and is not released from the support substrate 11, but is supported via the buried oxide film 13. 11 is fixed. The movable portion 30 and the beam portion 40 constitute a vibrator in the vibration type angular velocity sensor. The movable portion 30 is released from the support substrate 11 from which the buried oxide film 13 is removed on the back surface side. The beam portion 40 supports the movable portion 30 and displaces the movable portion 30 in the x-axis direction and the y-axis direction in order to detect angular velocity. Specific structures of the fixed portion 20, the movable portion 30, and the beam portion 40 will be described.

  The fixed portion 20 is a portion that supports the movable portion 30 and is formed with a pad for applying a driving voltage and a pad for taking out a detection signal used for angular velocity detection (not shown). In the present embodiment, each of these functions is realized by a single fixed unit 20, but for example, a support fixed unit for supporting the movable unit 30, a drive fixed unit to which a drive voltage is applied, and angular velocity detection. It may be configured to be divided into detection fixing parts to be used. In this case, for example, the fixing unit 20 shown in FIG. 1 is used as a support fixing unit, and a driving fixing unit and a detection fixing unit are provided so as to be connected to the supporting fixing unit, and a driving voltage is applied to the driving fixing unit. And a detection signal extraction pad may be provided in the detection fixing portion.

  Specifically, the fixed portion 20 has, for example, a quadrangular upper surface shape, and has a structure in which a detection beam 41 (to be described later) in the beam portion 40 is connected to the center portion of two opposite sides. The buried oxide film 13 is left below the fixed portion 20, and the fixed portion 20 is fixed to the support substrate 11 through the buried oxide film 13.

  The movable portion 30 is a portion that is displaced in response to the application of the angular velocity, and a detection weight that is vibrated according to the angular velocity when the angular velocity is applied during the driving vibration and a driving weight that is driven and vibrated by the application of the driving voltage. The configuration includes a weight. In the case of the present embodiment, as the movable portion 30, drive and detection weights 31, 32 that serve as a drive weight and a detection weight by the same weight are provided. The drive and detection weights 31 and 32 are disposed on both sides of the fixed portion 20 in the x-axis direction, and are disposed at equal intervals from the fixed portion 20. Each of the driving and detection weights 31 and 32 is configured with the same size (the same mass), and in the case of the present embodiment, the upper surface shape is configured with a quadrangle. Each of the drive / detection weights 31 and 32 is supported at both ends by being connected to a drive beam 42 (described later) provided in the beam portion 40 at two opposite sides. Under the driving and detection weights 31 and 32, the buried oxide film 13 is removed, and the driving and detection weights 31 and 32 are released from the support substrate 11. For this reason, each of the driving and detecting weights 31 and 32 can be driven to vibrate in the x-axis direction by deformation of the driving beam 42, and when the angular velocity is applied, the fixed portion including the y-axis direction by deformation of the driving beam 42 and the like. It is also possible to vibrate in the direction of rotation about 20.

  Further, in the present embodiment, the unnecessary vibration detection unit 60 that can accurately detect the unnecessary vibration generated in the vibration type angular velocity sensor is provided around the driving and detection weights 31 and 32 (see FIG. 5). The structure of the unnecessary vibration detector 60 will be described later.

  The beam portion 40 is configured to include a detection beam 41, a drive beam 42, and a support member 43.

  The detection beam 41 is a linear beam extending in the y-axis direction that connects the fixed portion 20 and the support member 43. The dimension of the detection beam 41 in the x-axis direction is thinner than the dimension in the z-axis direction, and can be deformed in the x-axis direction.

  The drive beam 42 is a linear beam extending in the y-axis direction connecting the drive and detection weights 31 and 32 and the support member 43, that is, in a direction parallel to the detection beam 41. The driving beam 42 provided on each of the driving and detection weights 31 and 32 and the detection beam 41 are equidistant. The dimension of the drive beam 42 in the x-axis direction is also thinner than the dimension in the z-axis direction, and can be deformed in the x-axis direction. Thereby, the drive and detection weights 31 and 32 can be displaced in the xy plane.

  The support member 43 is a linear member extending in the x-axis direction, and the detection beam 41 is connected at the center position of the support member 43, and the drive beams 42 are connected at both end positions. The support member 43 has a dimension in the y-axis direction larger than a dimension in the x-axis direction of the detection beam 41 and the drive beam 42. For this reason, the driving beam 42 is mainly deformed during driving vibration, and the detection beam 41 and the driving beam 42 are mainly deformed when the angular velocity is applied.

  With such a structure, the drive beam 42, the support member 43, and the drive / detection weights 31 and 32 form a frame having a quadrangular upper surface shape, and the vibration beam type in which the detection beam 41 and the fixing portion 20 are disposed inside thereof. An angular velocity sensor is configured.

  Further, the drive beam 42 is formed with a drive unit 51 and a control unit 52 as shown in FIGS. 1 and 3, and the detection beam 41 is detected with vibration as shown in FIG. A portion 53 is formed. The drive type 51, the control unit 52, and the vibration detection unit 53 are electrically connected to a control device (not shown) provided outside, so that the vibration type angular velocity sensor is driven.

  As shown in FIG. 1, the drive unit 51 is provided in the vicinity of the connection portion of each drive beam 42 to the support member 43, and two drive units 51 are arranged at a predetermined distance from each other in the y-axis direction. It is extended. As shown in FIG. 3, the driving unit 51 has a structure in which a lower layer electrode 51a, a driving thin film 51b, and an upper layer electrode 51c are sequentially stacked on the surface of the semiconductor layer 12 constituting the driving beam. The lower layer electrode 51a and the upper layer electrode 51c are composed of, for example, an Al electrode. The lower layer electrode 51a and the upper layer electrode 51c are connected to a pad or GND for applying a driving voltage (not shown) through the wiring members 51d and 51e drawn out to the fixing unit 20 through the support member 43 and the detection beam 41 shown in FIG. It is connected to the pad for connection. The driving thin film 51b is made of, for example, a lead zirconate titanate (PZT) film.

  In such a configuration, by generating a potential difference between the lower layer electrode 51a and the upper layer electrode 51c, the driving thin film 51b sandwiched therebetween is displaced, and the driving beam 42 is forcibly vibrated, thereby driving and driving. The detection weights 31 and 32 are driven to vibrate along the x-axis direction. For example, one drive unit 51 is provided at each end in the x-axis direction of each drive beam 42, and the drive thin film 51b of one drive unit 51 is displaced by a compressive stress and the other drive unit 51 is driven. The thin film 51b is displaced by tensile stress. Such voltage application is alternately and repeatedly performed on each drive unit 51, thereby driving and detecting weights 31 and 32 to be driven to vibrate along the x-axis direction.

  As shown in FIGS. 1 and 3, the control unit 52 is provided in the vicinity of the connecting portion with the support member 43 among the drive beams 42, and between the two drive units 51 arranged at each location. These are disposed at a predetermined distance from each drive unit 51 and extend in the y-axis direction. As shown in FIG. 3, the control unit 52 has a structure in which a lower layer electrode 52 a, a control thin film 52 b, and an upper layer electrode 52 c are sequentially stacked on the surface of the semiconductor layer 12 constituting the drive beam 42. The lower layer electrode 52a, the upper layer electrode 52c, and the control thin film 52b have the same configuration as the lower layer electrode 51a, the upper layer electrode 51c, and the driving thin film 51b that constitute the driving unit 51, respectively. The lower layer electrode 52a and the upper layer electrode 52c are connected to a pad or GND connection for applying a control voltage (not shown) through the wiring parts 52d and 52e drawn to the fixing part 20 through the support member 43 and the detection beam 41 shown in FIG. Is connected to the pad.

  In such a configuration, by generating a potential difference between the lower layer electrode 52a and the upper layer electrode 52c, the control thin film 52b sandwiched therebetween is displaced, and a desired vibration is applied to the drive beam 42. it can. Thereby, it is possible to control the vibrations of the drive and detection weights 31 and 32 and to apply vibrations that suppress unnecessary vibrations.

  As shown in FIGS. 1 and 4, the vibration detection unit 53 is provided in the vicinity of the connection portion of the detection beam 41 with the fixed unit 20, and is provided on each side of the detection beam 41 in the x-axis direction. It extends in the y-axis direction. As shown in FIG. 4, the vibration detection unit 53 has a structure in which a lower layer electrode 53a, a detection thin film 53b, and an upper layer electrode 53c are sequentially stacked on the surface of the semiconductor layer 12 constituting the detection beam 41. The lower layer electrode 53a, the upper layer electrode 53c, and the detection thin film 53b have the same configuration as the lower layer electrode 51a, the upper layer electrode 51c, and the driving thin film 51b that constitute the vibration detection unit 53, respectively. The lower layer electrode 53a and the upper layer electrode 53c are connected to a detection signal output pad (not shown) through the wiring portions 53d and 53e drawn to the fixing portion 20 shown in FIG.

  In the vibration type angular velocity sensor configured as described above, when the detection beam 41 is displaced as the angular velocity is applied, the detection thin film 53b is deformed accordingly. As a result, for example, an electric signal (current value in the case of constant voltage driving, current value in the case of constant current driving) between the lower layer electrode 53a and the upper layer electrode 53c changes, and this is used as a detection signal indicating the angular velocity. The signal is output to the outside through a detection signal output pad (not shown).

  Further, as shown in FIGS. 5 and 6, an unnecessary vibration detecting unit 60 is provided around the driving and detecting weights 31 and 32 and the periphery thereof. The detailed structure of the unnecessary vibration detection unit 60 will be described. 5 and 6 show the drive / detection weight 32 and the unnecessary vibration detector 60 provided around the drive / detection weight 32, the drive / detection weight 31 and the periphery thereof have the same structure. It has been.

  As shown in FIG. 5, the drive / detection weight 32 has a quadrangular shape and is connected to the drive beam 42 at two opposite sides parallel to the x-axis. A plurality of movable comb electrodes 61 are formed along the y-axis direction from the side parallel to the x-axis on both sides of the portion connected to the drive beam 42 in the drive / detection weight 32. Also, a plurality of movable comb electrodes 62 are formed along the x-axis direction on each of two opposite sides parallel to the y-axis of the drive / detection weight 32. A portion of the drive / detection weight 32 connected to the drive beam 42 is wide in the x-axis direction, and a z-axis vibration detection unit 63 is formed on the surface thereof. As shown in FIG. 6, the z-axis vibration detection unit 63 has a structure in which a lower layer electrode 63 a and a detection thin film 63 b formed of a piezoelectric film and an upper layer electrode 63 c are sequentially stacked on the surface of the semiconductor layer 12. The detection thin film 61b and the upper layer electrode 63c configured by the lower layer electrode 63a and the piezoelectric film have the same configurations as the lower layer electrode 51a and the upper layer electrode 51c and the drive thin film 51b that configure the drive unit 51, respectively.

  On the other hand, a comb fixing portion 64 is formed at a position facing the side parallel to the x-axis in the driving / detecting weight 32, and the comb fixing portion 64 includes a plurality of movable comb electrodes 61 and Opposing fixed comb electrodes 65 are formed. Further, a comb fixing portion 66 is formed at a position facing the side parallel to the y-axis in the driving and detecting weight 32, and the comb fixing portion 66 includes a plurality of movable comb electrodes 62 and Opposing fixed comb electrodes 67 are formed.

  Among these, the movable comb electrode 61 and the fixed comb electrode 65 function as an x-axis vibration detection unit that detects vibration in the x-axis direction of the driving and detection weight 32. The movable comb electrode 62 and the fixed comb electrode 67 function as a y-axis vibration detection unit that detects vibration in the y-axis direction of the driving and detection weight 32.

  Specifically, although not shown in the drawing, the comb-tooth fixing portions 64 and 66 are electrically connected to a wiring portion drawn out to the control device through the support substrate 11, for example. The movable comb electrodes 61 and 62 are electrically connected to the drive / detection weight 32, and the drive / detection weight 32 is drawn out to the fixed portion 20 through the drive beam 42, the support member 43, and the detection beam 41. It is electrically connected to the control device through wiring. In addition, the lower layer electrode 63 a and the upper electrode 63 c in the z-axis vibration detection unit 63 are electrically connected to the control device through wiring drawn out to the fixed unit 20 through the drive beam 42, the support member 43, and the detection beam 41.

  When the driving / detecting weight 32 vibrates in the x-axis direction, a capacitance change formed between the movable comb electrode 61 and the fixed comb electrode 65 is output to the control device through the comb fixing portion 64. Further, when the driving and detecting weight 32 vibrates in the y-axis direction, a capacitance change configured between the movable comb electrode 62 and the fixed comb electrode 67 is output to the control device through the comb fixing portion 66. Similarly, when the drive / detection weight 32 vibrates in the z-axis direction, the detection thin film 63b is displaced, and the electrical signal between the lower layer electrode 63a and the upper layer electrode 63c changes, which is output to the control device. The In this way, the x, y, and z vibration drive units can detect vibrations in the x-axis, y-axis, and z-axis directions of the drive / detection weight 32, respectively.

  As described above, the vibration type angular velocity sensor according to the present embodiment is configured. Next, the operation of the vibration type angular velocity sensor configured as described above will be described.

  First, as shown in FIG. 3, a drive voltage is applied to the drive unit 51 provided in the drive beam 42. Specifically, by generating a potential difference between the lower layer electrode 51a and the upper layer electrode 51c, the driving thin film 51b sandwiched therebetween is displaced. Of the two driving units 51 provided side by side, the driving thin film 51b of one driving unit 51 is displaced by compressive stress and the driving thin film 51b of the other driving unit 51 is displaced by tensile stress. . Such voltage application is alternately and repeatedly performed on each drive unit 51, thereby driving and vibrating the weights 31 and 32 for driving and detection along the x-axis direction. As a result, as shown in FIG. 7, the driving and detection weights 31 and 32 supported at both ends by the driving beam 42 are moved in opposite directions in the x-axis direction with the fixed portion 20 interposed therebetween. That is, both the driving and detection weights 31 and 32 are in a mode in which the state where the fixed portion 20 approaches and the state where the fixing portion 20 moves away are repeated.

  When this drive vibration is performed, if an angular velocity, that is, vibration around the x-axis with the fixed portion 20 as the central axis is applied to the vibration-type angular velocity sensor, as shown in FIG. In the detection mode, the weights 31 and 32 vibrate in the rotational direction around the fixed portion 20 including the y-axis direction. Accordingly, the detection beam 41 is also displaced, and the detection thin film 53 b provided in the vibration detection unit 53 is deformed along with the displacement of the detection beam 41. Thereby, for example, an electrical signal between the lower layer electrode 53a and the upper layer electrode 53c changes, and the generated angular velocity can be detected by inputting this electrical signal to a control device (not shown) provided outside. It becomes.

  When performing such an operation, for example, vibration transmitted from a part other than the vibration type angular velocity sensor (vehicle vibration, etc.), axial orientation deviation, processing asymmetry, existence of crystal defects, etc. Unnecessary vibration may occur.

  In this case, the detection thin film 63b provided in the z-axis vibration detection unit 63 is deformed by unnecessary vibration in the z-axis direction, and the electrical signal between the lower layer electrode 63a and the upper layer electrode 63b changes accordingly. This is input to a control device (not shown) provided outside as a detection signal indicating unnecessary vibration of the driving and detecting weight 31.

  However, the detection thin film 63b provided in the z-axis vibration detection unit 63 can be deformed by vibration in the x-axis or y-axis direction of the driving and detection weights 31 and 32. For this reason, vibrations in the x-axis direction of the drive and detection weights 31 and 32 are detected by the x-axis vibration detection unit, and vibrations in the y-axis direction are detected by the y-axis vibration detection unit. The vibration component in the z-axis direction generated based on the vibration in the x-axis direction and the y-axis direction is removed. Thereby, an unnecessary vibration component included in the vibration in the z-axis direction is extracted.

  Specifically, the distance between the movable comb electrode 61 and the fixed comb electrode 65 constituting the x-axis vibration detection unit is changed by the vibration in the x-axis direction of the driving and detection weights 31 and 32. The electric signal between the movable comb electrode 61 and the fixed comb electrode 65 changes. This is input to a control device (not shown) provided outside as a detection signal indicating vibration in the x-axis direction of the drive / detection weight 31. Similarly, the distance between the movable comb electrode 62 and the fixed comb electrode 67 constituting the y-axis vibration detection unit is changed by the vibration in the y-axis direction of the driving and detection weights 31 and 32, so that the movable comb-shaped electrode 67 is movable. An electric signal between the comb electrode 62 and the fixed comb electrode 67 changes. This is input to a control device (not shown) provided outside as a detection signal indicating vibration in the y-axis direction of the driving and detection weights 31 and 32. In this way, it is possible to detect vibrations in the x-axis and y-axis directions in the drive / detection weights 31 and 32.

  Then, vibration components in the x-axis and y-axis directions included in the vibration in the z-axis direction are removed. For example, assuming that the change in the electrical signal between the lower layer electrode 63a and the upper layer electrode 63b of the z-axis vibration detection unit 63 due to the vibration of the driving and detection weights 31 and 32 is represented by a voltage change, the detection thin film 63b Let ΔV be the amount of voltage change from when it is not deformed. Further, the voltage change amounts due to the deformation of the detection thin film 63b of the z-axis vibration detection unit 63 based on the vibrations of the driving and detection weights 31 and 32 in the x-axis and y-axis directions are respectively expressed by ΔVx and ΔVy, respectively When the voltage change amount due to deformation of the detection thin film 63b based only on unnecessary vibration in the direction is ΔVz, ΔV = ΔVx + ΔVy + ΔVz. Therefore, if ΔVx and ΔVy can be obtained in addition to ΔV, Δz can be obtained.

  On the other hand, ΔV can be obtained based on the electrical signal of the z-axis vibration detection unit 63. Further, regarding ΔVx and ΔVy, the x-axis vibration detection unit and the y-axis vibration detection unit can detect vibrations in the x-axis and y-axis directions. It is possible to determine how much the thin film 63b is deformed based on experimental results. Therefore, ΔVz can be obtained by subtracting ΔVx and ΔVy obtained from the detection results of the x-axis vibration detection unit and the y-axis vibration detection unit from ΔV obtained from the detection result of the z-axis vibration detection unit 63. Thereby, it is possible to extract only unnecessary vibration in the z-axis direction. Therefore, it is possible to accurately detect unnecessary vibration by separating the axis of vibration generated in the vibration type angular velocity sensor.

(Second Embodiment)
A second embodiment of the present invention will be described. In the present embodiment, the configuration of the z-axis vibration detection unit 63 is changed with respect to the first embodiment, and the others are the same as those in the first embodiment. Therefore, only the parts different from the first embodiment are described. explain.

  In the present embodiment, the z-axis vibration detection unit 63 is configured not to detect vibration using a piezoelectric film but to detect vibration based on a capacitance change.

  Also in this embodiment, the basic structure of the sensor structure is the same as that of the first embodiment. However, the lower electrode 63a, the detection thin film 63b, and the upper electrode 63c are formed as a part of the z-axis vibration detection unit 63 at a connection portion between the drive and detection weights 31 and 32 and the drive beam 42 in the sensor structure. Instead, a movable surface electrode 63d is provided.

  In addition, a fixed surface electrode 63e disposed opposite to the movable surface electrode 63d is provided at a position separated from the sensor structure, and the capacitive z-axis vibration detection unit 63 is configured by the movable surface electrode 63d and the fixed surface electrode 63e. Has been.

  Specifically, as shown in FIG. 9, the semiconductor layer 12 and the buried oxide film 13 are left on the substrate 10 on which the sensor structure is formed so as to surround the sensor structure. Then, the cavity 14 is formed by removing the buried oxide film 13 and the surface layer portion of the semiconductor layer 2 at a position below the fixed portion 20 in the sensor structure. In addition, a pattern wiring 16 is formed on the surface of the semiconductor layer 12 via an insulating film 15 in a portion surrounding the sensor structure, and a cap member 17 is disposed on the pattern wiring 16 to thereby form the sensor structure. The body is covered.

  The cap member 17 is formed by forming a wiring or the like on a semiconductor substrate 17a such as a silicon substrate. A plurality of through holes 17b are formed in the semiconductor substrate 17a, and an insulating film 17c is formed so as to cover the surface of the semiconductor substrate 17a including the inside of the plurality of through holes 17b. A conductor layer 17d is formed in the through hole 17b and on one surface of the semiconductor substrate 17a opposite to the substrate 10, with an insulating film 17c interposed therebetween. The conductor layer 17d is patterned so that each part of the sensor structure is not shown. A pad 17e for electrical connection with the control device is provided. As described above, the conductor layer 17d is formed in the through hole 17b, thereby forming a so-called TSV (Through-Silicon Via) structure. A protective film 17f is formed on the surface of the conductor layer 17d, and the pad 17e is exposed to the outside by forming an opening in the protective film 17f. A conductor layer 17g is also formed on the surface of the semiconductor substrate 17a on the sensor structure side through an insulating film 17c. A concave portion 17h in which a portion corresponding to the sensor structure is recessed is formed on the surface of the semiconductor substrate 17a on the sensor structure side so that the sensor structure does not come into contact with the cap member 17. A part of the conductor layer 17g is extended into the recess 17h. The fixed surface electrode 68 is constituted by this portion. The fixed surface electrode 68 configured as described above is preferably set to have a large area in consideration of the amount of movement of the movable surface electrode 63d so that the fixed surface electrode 68d is always opposed even if the movable surface electrode 63d moves.

  In FIG. 9, only a part of the conductor layers 17d and 17g is shown, but actually, the conductor layers 17d and 17g are patterned in a desired layout so as to be electrically connected to each part of the sensor structure. Yes.

  As described above, the z-axis vibration detection unit 63 may be a capacitive type configured by the movable surface electrode 63d and the fixed surface electrode 63e.

  Next, a manufacturing method of the vibration type angular velocity sensor having the above configuration will be described with reference to FIGS.

[Step shown in FIG. 10A]
After preparing the support substrate 11 composed of a silicon substrate or the like, the buried oxide film 13 is formed on the surface of the support substrate 11 by, for example, thermal oxidation. Subsequently, after forming a resist (not shown) on the buried oxide film 13, the buried oxide film 13 is patterned by performing a photolithography etching process. Then, the cavity 14 is formed by partially etching the support substrate 11 using the resist and the buried oxide film 13 as a mask. At this time, the buried oxide film 13 is left in the portion to be the fixing portion 20 (right side portion in the drawing) so that the support substrate 11 is not removed.

  Here, the cavity 14 is formed after the buried oxide film 13 is formed. However, after the cavity 14 is formed using the resist disposed on the surface of the support substrate 11 as a mask, the support substrate including the inside of the cavity 14 is formed. Alternatively, the buried oxide film 13 may be formed on the surface 11.

[Step shown in FIG. 10B]
The semiconductor layer 12 is attached on the support substrate via the buried oxide film 13. For example, a silicon substrate is disposed on the buried oxide film 13 made of SiO ₂ and annealed to attach the silicon substrate on the buried oxide film 13 by Si—Si direct bonding. Then, the semiconductor layer 12 having a predetermined thickness can be formed by grinding and polishing the silicon substrate.

[Step shown in FIG. 10 (c)]
Although simplified in the drawing, an electrode layer, a piezoelectric film, and an electrode layer are sequentially formed on the surface of the semiconductor layer 12 and then patterned to form a drive unit 51, a control unit 52, and a detection unit. 53 is configured.

[Step shown in FIG. 10 (d)]
After the insulating film 15 is formed on the surface of the semiconductor layer 12 on which the drive unit 51, the control unit 52, and the detection unit 53 are formed, this is patterned. Further, a wiring material such as an Al layer is formed on the semiconductor layer 17 including the insulating film 15 and then patterned, thereby pattern wiring 16 and various wiring portions 51d, 51e, 52d, 52e, 53d. , 53e, and the like.

[Step shown in FIG. 10 (e)]
After disposing a mask (not shown) on the semiconductor layer 12, the semiconductor layer 12 is patterned to release a portion of the sensor structure excluding the fixed portion 20, that is, the movable portion 30 and the beam portion 40 from the support substrate 11. . Thereby, a sensor structure is constituted.

[Step shown in FIG. 11A]
For forming the cap member 17, a semiconductor substrate 17 a is prepared separately from the substrate 10. Then, after disposing a mask (not shown) on the back surface of the semiconductor substrate 17a, a photolithography / etching process is performed to form a recess 17h on the back surface of the semiconductor substrate 17a.

[Step shown in FIG. 11B]
An insulating film 17c is formed by, for example, thermal oxidation so as to cover the entire surface of the semiconductor substrate 17a in which the recesses 17h are formed. Thereafter, after a wiring material such as Al is formed on the insulating film 17c, the conductor layer 17g is formed by patterning using a mask (not shown). Thereby, the cap member 17 before the through-hole 17b etc. are formed is comprised.

[Step shown in FIG. 12 (a)]
The substrate 10 on which the sensor structure is formed through the steps of FIG. 10A to FIG. 10E and the cap member 17 that has passed through the steps of FIG. 11A and FIG. For example, the cap member 17 can be attached to the substrate 10 by bonding the pattern wiring 16 formed on the front surface of the substrate 10 and the conductor layer 17g formed on the back surface of the cap member 17 by metal bonding. .

[Step shown in FIG. 12B]
After disposing a mask (not shown) on the surface of the cap member 17, a photolithography / etching process is performed to form a through hole 17b penetrating the front and back of the semiconductor substrate 17a. Thereby, the conductor layer 17 formed on the back surface of the semiconductor substrate 17a is exposed from the through hole 17b. Moreover, the inside of the through-hole 17b is also covered with the insulating film 17c as needed.

[Step shown in FIG. 12 (c)]
A conductor layer 17d is formed on the insulating film 17c formed on the surface of the semiconductor substrate 17a including the inside of the through hole 17b, and the conductor layer 17d is patterned using a mask (not shown). Thereby, the conductor layer 17d is electrically connected to the conductor layer 17g on the back surface side of the semiconductor substrate 17a exposed from each through hole 17b.

  Although the subsequent steps are not shown in the drawing, a protective film 17f is formed on the insulating film 17c formed on the surface of the semiconductor substrate 17a including the conductor layer 17d, and this is then patterned. A pad 17e is formed in which the conductor layer 17d is partially exposed. As described above, the vibration type angular velocity sensor according to the present embodiment is configured.

(Third embodiment)
A third embodiment of the present invention will be described. In this embodiment, the shape of the vibration type angular velocity sensor is changed with respect to the first embodiment, and the other parts are the same as those in the first embodiment. Therefore, only the parts different from the first embodiment will be described.

  The vibration type angular velocity sensor of the present embodiment shown in FIG. 13 also patterns the semiconductor layer 12 formed on the support substrate 11 via the buried oxide film 13, and fixes the fixed portion 100, the beam portion 110, the movable portion 120, and the like. It is manufactured by forming. Specifically, the vibration type angular velocity sensor of the present embodiment is configured as follows.

  A cantilever support beam 111 is formed from one side of the fixed portion 100 having a quadrangular upper surface, and a support member 112 extends in a direction perpendicular to the support beam 111. Specifically, the support beam 111 is coupled at the center position of the support member 112. Then, a detection beam 113 is formed on the opposite side of the support beam 111 with the support member 112 interposed therebetween, and a detection weight 121 is provided at the tip of the detection beam 113 and is driven in the same direction as the support beam 111 at both ends of the support member 112. A beam 114 is formed, and a driving weight 122 is provided at the tip thereof.

  Among these, the fixed part 100 corresponds to the fixed part 20 in the first embodiment. The support member 112, the detection beam 113, and the drive beam 114 correspond to the support member 43, the detection beam 102, and the detection beam 41 in the first embodiment, respectively, and play a similar role, and configure the beam portion 110 together with the support member 111. doing. The detection weight 121 and the driving weight 122 constitute the movable part 120. Although these are constituted separately, the roles of the driving and detection weights 31 and 32 are performed separately.

  The support beam 111 supports the detection beam 113, the detection weight 121, the drive beam 114, and the drive weight 122 via the support member 112, and is fixed to the fixing portion 100.

  Although various wirings are not shown, a drive unit 131 and a control unit 132 are formed on the drive beam 114, and a vibration detection unit 133 is formed on the detection beam 113. The drive unit 131, the control unit 132, and the vibration detection unit 133 play the same role as the drive unit 51, the control unit 52, and the vibration detection unit 53 in the first embodiment.

  As described above, the vibration-type angular velocity sensor having the structure in which the movable unit 120 and the beam unit 110 are cantilevered by the fixed unit 100 also includes a control unit 52 in addition to the drive unit 51 and the vibration detection unit 53. be able to.

  In such a configuration, as shown in FIG. 14, an unnecessary vibration detection unit 140 that detects unnecessary vibrations by detecting vibrations in the x-axis, y-axis, and z-axis directions with respect to the drive weight 122 is provided. .

  As shown in FIG. 14, the drive weight 122 has a quadrangular shape and is connected to the drive beam 114 on one side parallel to the x axis. A plurality of movable comb electrodes 141 are formed along the y-axis direction from sides parallel to the x-axis on both sides of the portion connected to the drive beam 114 in the drive weight 122. A plurality of movable comb electrodes 142 are also formed along the x-axis direction on each of two opposite sides of the drive weight 122 that are parallel to the y-axis. A portion of the drive weight 122 connected to the drive beam 114 is wide in the x-axis direction, and a z-axis vibration detection unit 143 is formed on the surface thereof.

  On the other hand, a comb-tooth fixing portion 144 is formed at a position facing the side parallel to the x-axis in the drive weight 122, and the comb-tooth fixing portion 144 is fixed to face the plurality of movable comb-tooth electrodes 141. Comb electrodes 145 are formed. A comb-tooth fixing portion 146 is formed at a position facing the side parallel to the y-axis in the driving weight 122, and the comb-tooth fixing portion 146 is fixed to face the plurality of movable comb-tooth electrodes 142. Comb electrodes 147 are formed.

  Among these, the movable comb electrode 141 and the fixed comb electrode 145 function as an x-axis vibration detection unit that detects vibration in the x-axis direction of the drive weight 122. The movable comb electrode 142 and the fixed comb electrode 147 function as a y-axis vibration detection unit that detects vibration in the y-axis direction of the drive weight 122. The movable comb electrode 141, the comb fixed portion 144, and the fixed comb electrode 145 have the same configuration as the movable comb electrode 61, the comb fixed portion 64, and the fixed comb electrode 65 shown in the first embodiment. Yes. Further, the movable comb electrode 142, the comb fixing portion 146, and the fixed comb electrode 147 have the same configuration as the movable comb electrode 62, the comb fixing portion 66, and the fixed comb electrode 67 shown in the first embodiment. Has been. The z-axis vibration detection unit 143 has the same configuration as the z-axis vibration detection unit 63 described in the first embodiment.

  As described above, the vibration type angular velocity sensor configured to cantilever the detection weight 121 and the drive weight 122 can extract unnecessary vibrations by detecting vibrations in the x-axis, y-axis, and z-axis directions in the drive unit 122. The same effects as those of the first embodiment can be obtained.

(Other embodiments)
The present invention is not limited to the embodiment described above, and can be appropriately changed within the scope described in the claims.

For example, in each of the above-described embodiments, the same piezoelectric film as that of the drive units 51 and 131 and the control units 52 and 132 is used as a detection element constituting the z-axis vibration detection units 63 and 163 in the unnecessary vibration detection units 60 and 140. A structure or a capacity type is used. However, in addition to the piezoelectric film and the capacitive type, other detection elements may be used as long as the detection elements can extract the displacement of the drive beams 42 and 114 as an electric signal. For example, a piezoresistor (gauge resistor) may be formed in the semiconductor layer 12 constituting the drive beams 42 and 114, and the piezoresistor may be used as a detection element. For example, a piezoresistor can be obtained by forming a p ⁺ -type layer or an n ⁺ -type layer in the surface layer portion of the semiconductor layer 12.

Similarly, in each of the above-described embodiments, a capacitive element is used as an example of the detection element constituting the x-axis vibration detection unit and the y-axis vibration detection unit in the unnecessary vibration detection units 60 and 140, but other configurations are used. May be. For example, a detection element using a piezoelectric film may be configured by laminating a lower electrode, a piezoelectric film, and an upper electrode on the side surfaces of the drive beams 42 and 114, that is, on a plane parallel to the z-axis, by sputtering or the like. Further, impurities are implanted into the side surfaces of the semiconductor layer 12 constituting the driving beams 42 and 114 by oblique ion implantation or the like to form a p ⁺ -type layer or an n ⁺ -type layer, thereby constituting a piezoresistor. A resistor may be used as the detection element.

  Furthermore, a capacitive detection element may be used as a detection element constituting the x-axis vibration detection unit and the y-axis vibration detection unit in the unnecessary vibration detection units 60 and 140, and a configuration different from the above may be used. For example, in each of the above embodiments, as shown in FIG. 15A, a squeeze-type capacitive sensor that causes a capacitance change due to a change in the distance between the movable comb electrode 61 and the fixed comb electrode 65 is used. Constitutes an x-axis vibration detector. On the other hand, as shown in FIG. 15B, the movable comb electrode 61 slides in the longitudinal direction, and the capacitance change is caused by the change in the facing area between the movable comb electrode 61 and the fixed comb electrode 65. You may comprise an x-axis vibration detection part with the slide-type capacity | capacitance sensor which arises. Of course, not only the x-axis vibration detection unit but also the y-axis vibration detection unit can be a slide-type capacitive sensor as well as a squeeze type.

  In addition, a comb-tooth electrode is provided on the detection beams 41 and 113, and a capacitive sensor including a comb-tooth electrode facing the comb-tooth electrode provided on the detection beams 41 and 113 as a detection fixing portion is used as a detection element. You may make it take out the change of the capacity | capacitance comprised between electrodes as an electrical signal.

  In each of the above embodiments, each vibration detection unit of the unnecessary vibration detection unit 60 is formed in a line-symmetric shape centering on a straight line parallel to the x-axis, y-axis, and z-axis, but is not necessarily in a line-symmetric shape. There is no need. However, if a line-symmetric shape is used, detection of the angular velocity can be performed with higher accuracy, such as obtaining detection signals from each symmetrically arranged element and taking the differential between them to enable cancellation of unnecessary vibration components. Is possible.

  The detection beams 41 and 113 are also provided with a control unit similar to the control units 52 and 132, and when unnecessary vibration is applied to the detection beams 41 and 113, the unnecessary vibration can be suppressed.

  Moreover, in the said embodiment, the drive parts 51 and 131, the control parts 52 and 132, and the vibration detection parts 53 and 133 are provided only in the vicinity of the support members 43 and 112 among the detection beams 41 and 113 and the drive beams 42 and 114. Structure. This is merely an example. For example, these may be provided in the entire area of the detection beams 41 and 113 and the drive beams 42 and 114.

  Further, in the above embodiment, the drive units 51 and 131 are piezoelectric types that perform drive vibration using a piezoelectric film, but electrostatic types that perform drive vibration using electrostatic force are used. May be.

DESCRIPTION OF SYMBOLS 10 Substrate 20,100 Fixed part 30,120 Movable part 31,32 Drive and detection weight 40,110 Beam part 41,113 Detection beam 42,114 Drive beam 51,131 Drive part 52,132 Control part 53,133 Vibration detection 60, 140 Unnecessary vibration detector 121 Detection weight 122 Drive weight

Claims (10)

A fixing part (20, 100) fixed to the substrate (1);
A movable part (30, 120) having a drive weight (31, 32, 122) and a detection weight (31, 32, 121);
A driving beam (42, 114) that supports the fixed weight while allowing the driving weight to move on a plane parallel to the plane of the substrate, and the detection weight on a plane parallel to the plane of the substrate A beam portion (40, 110) having a detection beam (41, 113) that is movable and supports the fixed portion,
The drive weight is driven to vibrate in one direction on the plane of the substrate, and angular velocity detection is performed based on the fact that the detection weight vibrates in the direction perpendicular to the one direction on the plane of the substrate as the angular velocity is applied. A vibration type angular velocity sensor,
Driving units (51, 131) for driving and vibrating the driving weight;
Detection elements (53, 133) for detecting displacement of the detection beam accompanying application of the angular velocity;
The vibration direction is an x-axis direction, a direction perpendicular to the x-axis direction on a plane parallel to the plane of the substrate is a y-axis direction, and the x-axis direction and the direction perpendicular to the y-axis direction are z-axis directions. An x-axis vibration detection unit (61, 65, 141, 145) that detects vibration in the x-axis direction of a weight, and a y-axis vibration detection unit (62, 67, 142) that detects vibration in the y-axis direction of the drive weight. 147), and an unnecessary vibration detection unit (60, 140) including a z-axis vibration detection unit (63, 143) for detecting the vibration of the drive weight in the z-axis direction. A characteristic vibration type angular velocity sensor. Drive and detection weights (31, 32) serving as the drive weight and the detection weight are arranged on both sides of the fixed portion as the center in the same direction as the direction of the drive vibration,
The detection beam (41) extends on both sides in a direction perpendicular to the direction of the drive vibration, with the fixed portion as a center,
The drive beam (42) extends on both sides in a direction perpendicular to the direction of the drive vibration, with the drive / detection weight as the center.
2. The detection beam according to claim 1, wherein a side of the detection beam opposite to the fixed portion and a side of the drive beam opposite to the driving and detection weight are connected to a linear support member (43). Vibration type angular velocity sensor. The fixed part, the movable part and the beam part are formed by patterning a semiconductor layer (12) provided in the substrate,
The x-axis vibration detector is formed by patterning the semiconductor layer, and has a movable comb electrode (61) extending from the driving / detection weight and a fixed comb electrode (fixed to the substrate). 65), and detecting the vibration in the x-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The y-axis vibration detection unit is formed by patterning the semiconductor layer, and includes a movable comb electrode (62) extending from the drive / detection weight and a fixed comb electrode (fixed to the substrate). 67), and detecting the vibration in the y-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The z-axis vibration detection unit is formed at a connection portion of the drive / detection weight with the drive beam, and a detection thin film (63a) and a piezoelectric thin film on the semiconductor layer ( 63b) and an upper layer electrode (63c) are stacked, and the vibration in the z-axis direction is detected based on the deformation of the thin film for detection disposed between the lower layer electrode and the upper layer electrode. 3. The vibration type angular velocity sensor according to claim 2, wherein The fixed part, the movable part and the beam part are formed by patterning a semiconductor layer (12) provided in the substrate,
The x-axis vibration detector is formed by patterning the semiconductor layer, and has a movable comb electrode (61) extending from the driving / detection weight and a fixed comb electrode (fixed to the substrate). 65), and detecting the vibration in the x-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The y-axis vibration detection unit is formed by patterning the semiconductor layer, and includes a movable comb electrode (62) extending from the drive / detection weight and a fixed comb electrode (fixed to the substrate). 67), and detecting the vibration in the y-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The z-axis vibration detecting unit is formed at a connecting portion of the driving and detecting weight with the driving beam, and is movable with respect to the movable surface electrode (63d) and the movable surface electrode formed on the surface of the semiconductor layer. And a fixed surface electrode (63e) arranged opposite to each other, wherein the vibration in the z-axis direction is detected based on a change in capacitance between the movable surface electrode and the fixed surface electrode. 3. The vibration type angular velocity sensor according to 2. A cap member (17) covering the semiconductor layer side of the substrate;
The vibration type angular velocity sensor according to claim 4, wherein the fixed surface electrode is formed on a back surface of the cap member on the semiconductor layer side. The cap member includes a semiconductor substrate (17a), a through hole (17b) penetrating a surface side opposite to the substrate of the semiconductor substrate and a back surface side serving as the substrate side, A conductor layer (17d) disposed from the front surface side including the inside of the through hole, and a conductor layer (17g) provided on the back surface side of the semiconductor substrate and connected to the conductor layer disposed in the through hole. And including
The vibration-type angular velocity sensor according to claim 5, wherein the fixed surface electrode is configured by the conductor layer provided on a back surface side of the semiconductor substrate. A control unit (52) including a control thin film (52b) disposed on the drive beam and configured by a piezoelectric film that generates vibrations that suppress unnecessary vibrations in which the drive weight moves in a direction normal to the plane of the substrate. 132),
The control unit is configured to detect the x-axis direction and the y-axis direction detected by the x-axis vibration detection unit and the y-axis vibration detection unit based on the z-axis direction vibration detected by the z-axis vibration detection unit. The vibration which suppresses the unnecessary vibration component contained in the vibration of the said z-axis direction which removed the vibration component of the said z-axis direction which has generate | occur | produced based on the vibration is generated. The vibration type angular velocity sensor according to any one of the above. The fixed part, the movable part and the beam part are formed by patterning a semiconductor layer (12) provided in the substrate,
The driving unit is disposed on the driving beam, and a driving thin film (51b) and an upper layer electrode (51c) configured of a lower layer electrode (51a) and a piezoelectric film for driving and vibrating the driving weight on the semiconductor layer. And a driving voltage is applied between the lower layer electrode and the upper layer electrode to deform the driving thin film to drive and vibrate the driving weight.
The control unit has a configuration in which a lower layer electrode (52a), the control thin film, and an upper layer electrode (52c) are stacked on the semiconductor layer, and a control voltage is applied between the lower layer electrode and the upper layer electrode. 8. The vibration type angular velocity sensor according to claim 7, wherein when applied, the control thin film is deformed to generate vibrations that suppress the unnecessary vibrations. The beam portion (110) has a support beam (111) fixed to the fixed portion,
A linear support member (112) extending in the direction of the drive vibration is provided on the opposite side of the fixed portion across the support beam,
The detection beam (113) extends in a direction perpendicular to the direction of the drive vibration on the opposite side to the fixed portion across the support member, and at the end portion on the opposite side to the support member. The detection weight (121) is connected,
The drive beam (42) extends in a direction perpendicular to the direction of the drive vibration on the opposite side to the fixed portion across the support member, and at the end opposite to the support member, the drive beam (42). The vibration type angular velocity sensor according to claim 1, wherein a driving weight (122) is connected. The fixed part, the movable part and the beam part are formed by patterning a semiconductor layer (12) provided in the substrate,
The x-axis vibration detector is formed by patterning the semiconductor layer, and includes a movable comb electrode (141) extending from the driving weight and a fixed comb electrode (145) fixed to the substrate. And detecting vibration in the x-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The y-axis vibration detection unit is formed by patterning the semiconductor layer, and includes a movable comb electrode (142) extending from the driving weight and a fixed comb electrode (147) fixed to the substrate. And detecting vibration in the y-axis direction based on a change in capacitance between the movable comb electrode and the fixed comb electrode,
The z-axis vibration detection unit is formed at a connection portion of the drive weight with the drive beam, and a thin film for detection and an upper layer electrode composed of a lower layer electrode and a piezoelectric film are stacked on the semiconductor layer. The vibration type angular velocity according to claim 9, wherein the vibration in the z-axis direction is detected based on deformation of the thin film for detection disposed between the lower layer electrode and the upper layer electrode. Sensor.

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