Actuator Device

Abstract

To provide an actuator device that can suppress deterioration of wiring provided at a connection part.SOLUTION: An actuator device comprises: a support part; a movable part; a first connection part which connects the movable part to the support part on a prescribed axis so that the movable part can oscillate around the axis; a first wiring provided at the first connection part; a second wiring provided at the movable part; a first insulation layer having a first opening that exposes a surface on a side opposite to the movable part at a first connection portion of one wiring of the first wiring and the second wiring that is positioned at the movable part; and a second insulation layer which covers the first wiring and the second wiring. The other wiring of the first wiring and the second wiring is connected to the surface of the first connection portion at the first opening, and a region of the surface of the insulation layer on a side opposite to movable part that corresponds to a corner of the other wiring of the first wiring and the second wiring convexly curves toward the opposite side of the movable part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an actuator device configured as, for example, a MEMS (Micro Electro Mechanical Systems) device. [Background technology]

[0002] Known MEMS devices include an actuator device that includes a support portion, a movable portion, a connecting portion that connects the movable portion to the support portion along an axis so that the movable portion can oscillate about a predetermined axis, and wiring provided on the connecting portion and the support portion. In such actuator devices, for example, the movable portion may oscillate at high speeds at its resonant frequency level (several kilohertz to several tens of kilohertz). In such cases, metal fatigue may occur in the wiring on the connecting portion, which may lead to deterioration of characteristics, breakage, etc.

[0003] In order to solve the problems described above, a technology has been proposed in which a first wiring made of a high-rigidity metal material is provided on a connecting portion, and the first wiring and a second wiring made of a low-rigidity metal material are electrically connected to each other in a low-stress region on a support portion (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 8,218,218 Summary of the Invention [Problem to be solved by the invention]

[0005] The inventor discovered that by positioning the electrical connection position between the first wiring and the second wiring on the support portion, and by devising the electrical connection structure between the first wiring and the second wiring, it is possible to further suppress deterioration of the wiring provided on the connecting portion and the support portion.

[0006] An object of the present invention is to provide an actuator device that can suppress deterioration of wiring provided on a connecting portion and a supporting portion. [Means for solving the problem]

[0007] The actuator device of the present invention comprises a support portion, a movable portion, a connecting portion that connects the movable portion to the support portion on an axis so that the movable portion can swing around a predetermined axis, a first wiring provided on the connecting portion, a second wiring provided on the support portion, and an insulating layer that has a first opening that exposes the surface opposite to the support portion at a first connection portion of one of the first wiring and the second wiring that is located on the support portion and covers a corner of the first connection portion, wherein the first metal material that constitutes the first wiring has higher rigidity than the second metal material that constitutes the second wiring, and the other of the first wiring and the second wiring is connected to the surface of the first connection portion at the first opening.

[0008] In this actuator device, the first metal material constituting the first wiring provided on the connecting portion is more rigid than the second metal material constituting the second wiring provided on the support portion. This suppresses deterioration of the first wiring provided on the connecting portion. At this time, deformation (warping, etc.) of the support portion, which is caused by the entire wiring provided on the connecting portion and the support portion being made of a highly rigid metal material, is also suppressed. Furthermore, the first wiring and the second wiring are connected to each other at a first connection portion located on the support portion. This reduces stress acting on the first connection portion, thereby suppressing deterioration of the first connection portion. Furthermore, the corners of the first connection portion are covered by an insulating layer, and the first wiring and the second wiring are connected to each other at the surface of the support portion opposite the first connection portion exposed by the first opening in the insulating layer. This reduces stress acting from the first wiring to the second wiring by the insulating layer, thereby suppressing deterioration of the second wiring made of a second metal material less rigid than the first metal material. Therefore, this actuator device can suppress deterioration of the wiring provided on the connecting portion and the support portion.

[0009] In the actuator device of the present invention, the first connection portion may be spaced a predetermined distance from the axis. This configuration makes it possible to reduce stress acting on the first connection portion while ensuring an area on the support portion for providing other components.

[0010] In the actuator device of the present invention, the distance may be greater than half the minimum width of the connecting portion. This configuration ensures an area on the support portion for providing other components, while further reducing the stress acting on the first connecting portion.

[0011] In the actuator device of the present invention, the cross-sectional area of ​​the first wiring may be larger than the cross-sectional area of ​​the second wiring. With this configuration, even if the resistivity of the first metal material is higher than the resistivity of the second metal material, an increase in the resistance value of the first wiring can be suppressed.

[0012] In the actuator device of the present invention, the width of the first wire may be greater than the width of the second wire. With this configuration, it is possible to prevent interference with twisting of the connecting portion, while ensuring the cross-sectional area of ​​the first wire and preventing an increase in the resistance value of the first wire.

[0013] In the actuator device of the present invention, the first opening may be located away from a corner of the first connection portion. This configuration can reliably reduce the stress acting from the first wiring to the second wiring.

[0014] In the actuator device of the present invention, the surface of the insulating layer opposite the support portion may have a region corresponding to the corner of the first connection portion that is convexly curved toward the opposite side of the support portion. This configuration further reduces the stress acting from the first wiring to the second wiring.

[0015] The actuator device of the present invention further includes a coil provided on the movable part, a magnetic field generating unit that applies a magnetic field to the coil, and a third wiring provided on the movable part and electrically connected to the coil, wherein the insulating layer has a second opening that exposes a surface of one of the first wiring and the third wiring that is located on the movable part at a second connection portion opposite the movable part and covers a corner of the second connection portion, the first metal material has higher rigidity than the third metal material constituting the third wiring, and the other of the first wiring and the third wiring is connected to the surface of the second connection portion at the second opening. With this configuration, deterioration of the connecting portion and the wiring provided on the movable part can be suppressed.

[0016] The actuator device of the present invention may further include a frame that supports the support portion and the movable portion, and the support portion may be connected to the frame so as to be swingable around an axis that intersects with the axis. With this configuration, the movable portion can be swung around each of the two axes that intersect with each other.

[0017] The actuator device of the present invention may further include a mirror provided on the movable part. With this configuration, the mirror can be swung around an axis and used for scanning light, etc. [Effects of the Invention]

[0018] According to the present invention, deterioration of the wiring provided on the connecting portion and the supporting portion can be suppressed. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a perspective view of an actuator device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a plan view of the circuit configuration of the actuator device of FIG. [Figure 3] FIG. 3 is a partially enlarged view of FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 4 is a cross-sectional view taken along line VV in FIG. [Figure 6]FIG. 10 is a cross-sectional view of a first connection portion of an actuator device according to a first modified example. [Figure 7] FIG. 10 is a cross-sectional view of a first connection portion of an actuator device according to a second modified example. [Figure 8] FIG. 10 is a partial enlarged view of an actuator device according to a third modified example. DETAILED DESCRIPTION OF THE INVENTION

[0020] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the same or equivalent elements will be designated by the same reference numerals, and redundant description will be omitted.

[0021] 1 and 2, the actuator device 1 includes a mirror 2, a magnetic field generating unit 3, a frame 4, a support unit 5, a movable unit 6, a pair of connecting units 7, and a pair of connecting units 8. The actuator device 1 is configured as a MEMS device that oscillates the mirror 2 about a first axis X1 and a second axis X2 that are perpendicular to each other. Such an actuator device 1 is used, for example, in an optical switch for optical communication, an optical scanner, or the like.

[0022] The mirror 2 is a light-reflecting film made of a metal film. The mirror 2 has a circular shape in a plan view (when viewed from a direction perpendicular to the plane on which at least the support portion 5, the movable portion 6, and the pair of connecting portions 7 are arranged). The metal material constituting the mirror 2 is, for example, aluminum (Al), gold (Au), or silver (Ag).

[0023] The magnetic field generating unit 3 is a rectangular flat plate having a pair of main surfaces. The magnetic field generating unit 3 applies a magnetic field to a coil 11 provided on the support unit 5 and a coil 12 provided on the movable unit 6 (the coils 11 and 12 will be described later). The magnetic field generating unit 3 is composed of, for example, permanent magnets. The magnetic poles in the magnetic field generating unit 3 are arranged in a Halbach array, for example.

[0024] The frame 4 is a flat frame body having a rectangular shape in a plan view. The frame 4 is disposed on one main surface of the magnetic field generating unit 3. The frame 4 supports the support unit 5, the movable unit 6, the mirror 2, etc. via a pair of connecting units 7. Each connecting unit 7 connects the support unit 5 to the frame 4 on the first axis X1 so that the support unit 5 can swing around the first axis X1. In other words, each connecting unit 7 functions as a torsion bar. Each connecting unit 7 has a serpentine shape in a plan view to improve strength and facilitate adjustment of the torsional spring constant.

[0025] The support unit 5 is a flat frame body having a rectangular shape in a plan view, and is located inside the frame unit 4. The support unit 5 is disposed so as to face one main surface of the magnetic field generation unit 3 and to be spaced apart from the one main surface of the magnetic field generation unit 3. The support unit 5 supports the movable unit 6, the mirror 2, etc. via a pair of connecting units 8. Each connecting unit 8 connects the movable unit 6 to the support unit 5 on the second axis X2 so that the movable unit 6 can swing around the second axis X2. In other words, each connecting unit 8 functions as a torsion bar.

[0026] As shown in FIG. 3 , each connecting portion 8 is a flat, generally rectangular member in a plan view, extending along the second axis X2. The end 8a of each connecting portion 8 on the movable portion 6 side increases in width as it approaches the movable portion 6. Here, the width of a connecting portion 8 refers to the length of the connecting portion 8 in a direction perpendicular to the second axis X2 in a plan view. When the connecting portion 8 is widened at at least one end and connected to the support portion 5 or the movable portion 6, the connecting portion 8 is, for example, a region whose width is 1.5 times the minimum width W0. In FIG. 3 , the boundary B between the connecting portion 8 and the support portion 5 and the boundary B between the connecting portion 8 and the movable portion 6 are indicated by two-dot chain lines. Note that the connecting portion 8 may be a region in which the stress acting upon the swinging of the movable portion 6 relative to the support portion 5 is 2 / 3 times the maximum stress.

[0027] 1 and 2, the movable part 6 is a flat frame body having a rectangular shape in a plan view, and is located inside the support part 5. The movable part 6 is arranged to face one main surface of the magnetic field generation part 3 and to be spaced apart from the one main surface of the magnetic field generation part 3. A placement part 9 having a circular shape in a plan view is provided inside the movable part 6. The mirror 2 is arranged on the placement part 9. In other words, the mirror 2 is provided on the movable part 6. The frame part 4, the support part 5, the movable part 6, the pair of connecting parts 7, and the pair of connecting parts 8 are integrally formed from, for example, silicon (Si).

[0028] As shown in Fig. 2, the actuator device 1 further includes a coil 11 provided in the support portion 5 and a coil 12 provided in the movable portion 6. The coil 11 is embedded in the support portion 5, and the coil 12 is embedded in the movable portion 6. Each of the coils 11 and 12 is made of a metal material such as copper (Cu). Note that in Fig. 2, each wire is shown with a solid line for ease of understanding, but each wire such as the coils 11 and 12 is actually covered with an insulating layer 52 and / or an insulating layer 53, which will be described later.

[0029] The coil 11 is wound in a spiral shape with multiple turns in a plan view. One end of the wiring 14a is electrically connected to the inner end of the coil 11. One end of the wiring 14b is electrically connected to the outer end of the coil 11. Each of the wirings 14a, 14b is made of a metal material such as aluminum. Each of the wirings 14a, 14b is provided on one of the connecting portions 7 and extends from the support portion 5 to the frame portion 4. The other end of the wiring 14a is electrically connected to an electrode 15a provided on the support portion 5, and the other end of the wiring 14b is electrically connected to an electrode 15b provided on the support portion 5. Each of the electrodes 15a, 15b is electrically connected to a control circuit or the like. The wiring 14a crosses the coil 11 three-dimensionally so as to pass above the coil 11.

[0030] The coil 12 is wound in a spiral shape multiple times in a plan view. One end of the wiring 16a is electrically connected to the inner end of the coil 12. One end of the wiring 16b is electrically connected to the outer end of the coil 12. Each of the wirings 16a, 16b is provided on the pair of connecting portions 8, the support portion 5, and the other connecting portion 7, and extends from the movable portion 6 to the frame portion 4. The other end of the wiring 16a is electrically connected to an electrode 17a provided on the support portion 5, and the other end of the wiring 16b is electrically connected to an electrode 17b provided on the support portion 5. Each of the electrodes 17a, 17b is electrically connected to a control circuit, etc. The wiring 16a crosses the coil 12 three-dimensionally so as to pass above the coil 12.

[0031] Each of the wirings 16a, 16b has a first wiring 21 provided on each connecting portion 8, a second wiring 31 provided on the support portion 5, and a third wiring 41 provided on the movable portion 6. Hereinafter, the configurations of the first wiring 21, the second wiring 31, and the third wiring 41 in the vicinity of one of the connecting portions 8 will be described with reference to FIGS. 3, 4, and 5. The configurations of the first wiring 21, etc. in the vicinity of the other connecting portion 8 are similar to the configurations of the first wiring 21, etc. in the vicinity of one of the connecting portions 8, and therefore will not be described again. Note that an insulating layer 52 (see FIGS. 4 and 5), which will be described later, is omitted from FIG. 3.

[0032] The first wiring 21 is made of a first metal material. The first wiring 21 is provided over the support portion 5, the connecting portion 8, and the movable portion 6. The first wiring 21 has a first portion 22, a second portion 23, and a third portion 24. The first portion 22 extends along the second axis X2 on the support portion 5, the connecting portion 8, and the movable portion 6. The second portion 23 extends on the support portion 5 from an end of the first portion 22 on the support portion 5 side to the other connecting portion 7 side. The third portion 24 extends on the movable portion 6 from an end of the first portion 22 on the movable portion 6 side to one connecting portion 7 side. The extending direction of the first portion 22 and the extending direction of the second portion 23 are mutually orthogonal, and the extending direction of the first portion 22 and the extending direction of the third portion 24 are mutually orthogonal.

[0033] The first wiring 21 is electrically connected to the second wiring 31 at a first connection portion 25 located at an end of the support portion 5. The first wiring 21 is electrically connected to the third wiring 41 at a second connection portion 26 located at an end of the movable portion 6. The first connection portion 25 is spaced a predetermined distance D1 from the second axis X2. The distance D1 is greater than half the minimum width W0 of the connecting portion 8. The second connection portion 26 is spaced a predetermined distance D2 from the second axis X2. The distance D2 is greater than half the minimum width W0 of the connecting portion 8. The first portion 22, the second portion 23, and the third portion 24 all have the same width. The width W1 of the first wiring 21 is at least half the minimum width W0 of the connecting portion 8, and in this example, is at least two-thirds the minimum width W0. Here, the width W1 of the first wiring 21 refers to the length of the first wiring 21 in a direction perpendicular to the extension direction of the first wiring 21 in a plan view. The width W1 of the first wiring 21 is, for example, about 50 to 100 μm.

[0034] The second wiring 31 is made of a second metal material. One end of the second wiring 31 is electrically connected to the first wiring 21. The other end of the second wiring 31 is electrically connected to the electrode 17a. One end of the second wiring 31 is provided with a widened portion 32 that is wider than other portions. The second wiring 31 is electrically connected to the first connection portion 25 of the first wiring 21 at the widened portion 32.

[0035] The third wiring 41 is made of a third metal material. One end of the third wiring 41 is electrically connected to the first wiring 21. The other end of the third wiring 41 is electrically connected to the coil 12. One end of the third wiring 41 is provided with a widened portion 42 that is wider than other portions. The third wiring 41 is electrically connected to the second connection portion 26 of the first wiring 21 at the widened portion 42.

[0036] The first metal material constituting the first wiring 21 has higher rigidity than the second metal material constituting the second wiring 31. The first metal material constituting the first wiring 21 has higher rigidity than the third metal material constituting the third wiring 41. In other words, the second metal material constituting the second wiring 31 has lower rigidity than the first metal material constituting the first wiring 21. The third metal material constituting the third wiring 41 has lower rigidity than the first metal material constituting the first wiring 21. Examples of combinations of the first metal material and the second metal material include a combination of tungsten (W) (first metal material) and aluminum (second metal material), a combination of tungsten (first metal material) and copper (second metal material), and a combination of tungsten (first metal material) and gold (second metal material). Examples of combinations of the first metal material and the third metal material include a combination of tungsten (W) (first metal material) and aluminum (third metal material), a combination of tungsten (first metal material) and copper (third metal material), a combination of tungsten (first metal material) and gold (third metal material), etc. The first metal material may be an aluminum alloy (such as AL-Cu), nickel (Ni), platinum (Pt), etc.

[0037] In the actuator device 1, the width W1 of the first wiring 21 is larger than the width W2 of the second wiring 31 and the width W3 of the third wiring 41. The thickness of the first wiring 21 is equal to the thickness of the second wiring 31 and the thickness of the third wiring 41. Therefore, the cross-sectional area of ​​the first wiring 21 is larger than the cross-sectional area of ​​the second wiring 31 and the cross-sectional area of ​​the third wiring 41. Here, the width W2 of the second wiring 31 refers to the length of the second wiring 31 (excluding the widened portion 32) in a direction perpendicular to the extension direction of the second wiring 31 in a plan view. The width W3 of the third wiring 41 refers to the length of the third wiring 41 (excluding the widened portion 42) in a direction perpendicular to the extension direction of the third wiring 41 in a plan view. The cross-sectional area of ​​the first wiring 21 refers to the area of ​​a cross section perpendicular to the extension direction of the first wiring 21. The cross-sectional area of ​​the second wiring 31 refers to the area of ​​a cross section perpendicular to the extension direction of the second wiring 31. The cross-sectional area of ​​the third wiring 41 refers to the area of ​​a cross section perpendicular to the extending direction of the third wiring 41. The width of the second wiring 31 is, for example, about 5 to 10 μm.

[0038] 4, the actuator device 1 further includes insulating layers 51, 52, and 53. Each of the insulating layers 51, 52, and 53 is, for example, a silicon oxide film (SiO2).

[0039] The insulating layer 51 is provided on the surfaces of the frame portion 4, the support portion 5, the movable portion 6, the pair of connecting portions 7, and the pair of connecting portions 8. The first wiring 21 is provided on the insulating layer 51. In other words, the first wiring 21 is provided on the support portion 5 with the insulating layer 51 interposed therebetween.

[0040] The insulating layer 52 is provided on the insulating layer 51 so as to cover the first wiring 21. The insulating layer 52 is provided over the frame 4, the support 5, the movable portion 6, the pair of connecting portions 7, and the pair of connecting portions 8. The insulating layer 52 has a first opening 52a exposing a surface 25a of the first connection portion 25 opposite the support portion 5. The first opening 52a is a hole having a circular shape in a plan view. The first opening 52a is a predetermined distance away from a corner 25b of the first connection portion 25. The insulating layer 52 covers the corner 25b of the first connection portion 25. A region 53d of the surface of the insulating layer 52 opposite the support portion 5, which corresponds to the corner 25b, is curved convexly toward the opposite side of the support portion 5. Here, the corner 25b of the first connection portion 25 refers to a portion along the outer edge of the surface 25a of the first connection portion 25 (a portion where at least two surfaces intersect in the first connection portion 25).

[0041] The second wiring 31 is provided on the insulating layer 52. That is, the second wiring 31 is provided on the support part 5 via the insulating layers 51 and 52. The widened part 32 of the second wiring 31 rides on the first connection part 25 so as to cover the first opening 52a. A part 32a of the widened part 32 is disposed within the first opening 52a and is connected to the surface 25a of the first connection part 25 at the first opening 52a. The widened part 32 has a recess 32b on the opposite surface of the support part 5 at a position corresponding to the first opening 52a. The recess 32b is formed when the part 32a of the widened part 32 enters the first opening 52a during the formation of the second wiring 31.

[0042] The electrical connection structure between the first wiring 21 and the third wiring 41 is similar to the electrical connection structure between the first wiring 21 and the second wiring 31 described above. That is, as shown in FIG. 3 , the insulating layer 52 has a second opening 52b that exposes the surface 26a of the second connection portion 26 opposite the movable portion 6. The second opening 52b is a hole that is circular in plan view. The second opening 52b is a predetermined distance away from the corner 26b of the second connection portion 26. The insulating layer 52 covers the corner 26b of the second connection portion 26. A region of the surface of the insulating layer 52 opposite the movable portion 6 that corresponds to the corner 26b is convexly curved toward the opposite side of the movable portion 6. Here, the corner 26b of the second connection portion 26 refers to a portion along the outer edge of the surface 26a of the second connection portion 26 (a portion where at least two surfaces intersect in the second connection portion 26).

[0043] The third wiring 41 is provided on the insulating layer 52. That is, the third wiring 41 is provided on the movable part 6 via the insulating layers 51, 52. The widened part 42 of the third wiring 41 rides on the second connection part 26 so as to cover the second opening 52b. A part of the widened part 42 is disposed within the second opening 52b and is connected to the surface 26a of the second connection part 26 at the second opening 52b. The widened part 42 has a recess on the surface opposite to the support part 5 at a position corresponding to the second opening 52b. The recess is formed when a part of the widened part 42 enters the second opening 52b during the formation of the third wiring 41.

[0044] The insulating layer 53 is provided on the insulating layer 52 so as to cover the second wiring 31 and the third wiring 41. The insulating layer 53 is provided over the frame 4, the support 5, the movable portion 6, the pair of connecting portions 7, and the pair of connecting portions 8. The insulating layer 53 has a recess 53a on the surface opposite the support 5 at a position corresponding to the first opening 52a. The recess 53a is formed when a portion of the insulating layer 53 enters the recess 32b during the formation of the insulating layer 53. The insulating layer 53 has a recess on the surface opposite the support 5 at a position corresponding to the second opening 52b. The recess in the insulating layer 53 is formed when a portion of the insulating layer 53 enters the recess in the widened portion 42 during the formation of the insulating layer 53.

[0045] As shown in FIG. 5 , the movable part 6 has a groove 55 having a shape corresponding to the coil 12. An insulating layer 51 is provided on the inner surface of the groove 55. A seed layer 56 is provided on the insulating layer 51 in the groove 55. The seed layer 56 is made of, for example, titanium nitride (TiN). The coil 12 is disposed in the groove 55 via the insulating layer 51 and the seed layer 56. The coil 12 is formed by, for example, burying a metal material such as copper in the groove 55 by a damascene method. The insulating layer 52 is provided so as to cover the coil 12 disposed in the groove 55. The third wiring 41 is electrically connected to the coil 12 through an opening provided in the insulating layer 52 so as to expose the inner end of the coil 12.

[0046] During the formation process of the coil 12, a groove 13 is formed along the boundary between the surface of the coil 12 facing the insulating layer 52 and the seed layer 56. The insulating layer 52 has a groove 52c at a position corresponding to the groove 13 on the surface opposite the movable portion 6. The groove 52c is formed when a part of the insulating layer 52 enters the groove 13 during the formation of the insulating layer 52. The third wiring 41 has a groove 41a at a position corresponding to the groove 12a on the surface opposite the movable portion 6. The groove 41a is formed when a part of the third wiring 41 enters the groove 52c during the formation of the third wiring 41. The insulating layer 53 has a groove 53b at a position corresponding to the groove 12a on the surface opposite the movable portion 6. The groove 53b is formed when a part of the insulating layer 53 enters the groove 41a during the formation of the insulating layer 53.

[0047] In the actuator device 1, when a current flows through the coil 11, the magnetic field generated by the magnetic field generating unit 3 generates a Lorentz force in a predetermined direction on the electrons flowing through the coil 11. As a result, the coil 11 receives a force in the predetermined direction. Therefore, by controlling the direction or magnitude of the current flowing through the coil 11, the support unit 5 can be swung about the first axis X1. Similarly, by controlling the direction or magnitude of the current flowing through the coil 12, the movable unit 6 can be swung about the second axis X2. Therefore, by controlling the direction or magnitude of the currents in the coils 11 and 12, respectively, the mirror 2 can be swung about the first axis X1 and the second axis X2, which are perpendicular to each other. Furthermore, by passing a current of a frequency corresponding to the resonant frequency of the movable unit 6 through the coil 12, the movable unit 6 can be swung at high speed at the resonant frequency level.

[0048] In the actuator device 1 described above, the first metal material constituting the first wiring 21 provided on the connecting portion 8 is more rigid than the second metal material constituting the second wiring 31 provided on the support portion 5. This suppresses deterioration of the first wiring 21 provided on the connecting portion 8. At the same time, deformation (warping, etc.) of the support portion 5, which is caused by the entire wiring provided on the connecting portion 8 and the support portion 5 being made of the highly rigid first metal material, is also suppressed. Furthermore, the first wiring 21 and the second wiring 31 are connected to each other at a first connection portion 25 located on the support portion 5. This reduces stress acting on the first connection portion 25, suppressing deterioration of the first connection portion 25. Furthermore, in the actuator device 1, the corner 25b of the first connection portion 25 is covered by the insulating layer 52, and the first wiring 21 and the second wiring 31 are connected to each other at a surface 25a of the first connection portion 25 opposite the support portion 5, which is exposed by the first opening 52a in the insulating layer 52. As a result, the stress acting from the first wiring 21 to the second wiring 31 is reduced by the insulating layer 52, thereby suppressing deterioration of the second wiring 31 made of the second metal material that is less rigid than the first metal material. Therefore, according to the actuator device 1, it is possible to suppress deterioration of the wirings 16a, 16b provided on the connecting portion 8 and the support portion 5. Furthermore, since the first wiring 21 and the second wiring 31 are directly connected, it is possible to reduce the resistance of the wirings 16a, 16b provided on the connecting portion 8 and the support portion 5.

[0049] In the actuator device 1, the first connection portion 25 is spaced a predetermined distance D from the second axis X2. This makes it possible to reduce the stress acting on the first connection portion 25 while ensuring an area on the support portion 5 for providing other components (for example, the coil 11). That is, compared to the case where the stress acting on the first connection portion 25 is reduced by ensuring a distance along the second axis X2 between the first connection portion 25 and the coupling portion 8, it is possible to ensure an area on the support portion 5 for providing other components.

[0050] In the actuator device 1, the distance D is greater than half the minimum width W0 of the connecting portion 8. This makes it possible to further reduce the stress acting on the first connecting portion 25 while ensuring an area on the support portion 5 for providing other components.

[0051] In the actuator device 1, the cross-sectional area of ​​the first wiring 21 is larger than the cross-sectional area of ​​the second wiring 31. As a result, even if the resistivity of the first metal material constituting the first wiring 21 is higher than the resistivity of the second metal material constituting the second wiring 31, an increase in the resistance value of the first wiring 21 can be suppressed.

[0052] In the actuator device 1, the width of the first wiring 21 is greater than the width of the second wiring 31. This makes it possible to prevent the twisting of the connecting portion 8 from being hindered, while ensuring the cross-sectional area of ​​the first wiring 21 and suppressing an increase in the resistance value of the first wiring 21.

[0053] In the actuator device 1, the first opening 52a is located away from the corner 25b of the first connection portion 25. This makes it possible to reliably reduce the stress acting on the second wiring 31 from the first wiring 21.

[0054] In the actuator device 1, a region 53d of the surface of the insulating layer 52 opposite the support portion 5, which corresponds to the corner 25b, is curved in a convex shape toward the opposite side of the support portion, thereby further reducing the stress acting from the first wiring 21 to the second wiring 31.

[0055] In the actuator device 1, the first metal material constituting the first wiring 21 provided on the connecting portion 8 has higher rigidity than the third metal material constituting the third wiring 41 provided on the movable portion 6. Furthermore, the first wiring 21 and the third wiring 41 are connected to each other at the second connection portion 26 located on the movable portion 6. Furthermore, the corner 26b of the second connection portion 26 is covered by the insulating layer 52, and the first wiring 21 and the third wiring 41 are connected to each other at the surface 26a of the second connection portion 26 opposite the movable portion 6, which is exposed by the second opening 52b of the insulating layer 52. Therefore, deterioration of the wirings 16a, 16b provided on the connecting portion 8 and the movable portion 6 can be suppressed.

[0056] The actuator device 1 further includes a frame 4 that supports a support portion 5 and a movable portion 6, and the support portion 5 is connected to the frame 4 so as to be swingable about a first axis X1 that is perpendicular to the second axis X2. This allows the movable portion 6 to swing about each of the two axes that are perpendicular to each other.

[0057] The actuator device 1 further includes a mirror 2 provided on the movable part 6. This allows the mirror 2 to be swung about each of the first axis X1 and the second axis X2, and can be used for light scanning, etc.

[0058] In the actuator device 1, the second wiring 31 is connected to a surface 25a of the first wiring 21 at a first connection portion 25 located on the support portion 5, on the opposite side from the support portion 5. This allows stress acting from the first wiring 21 to the second wiring 31 to escape to the opposite side of the support portion 5, thereby suppressing deterioration of the second wiring 31 made of a second metal material that is less rigid than the first metal material. In other words, it is possible to prevent the stress acting from the second wiring 31 on the first wiring 21 and the reaction force from the support portion 5 from acting concentratedly on the end of the second wiring 31, as would occur if the end of the second wiring 31 were sandwiched between the first wiring 21 and the support portion 5. This also enables the actuator device 1 to suppress deterioration of the wirings 16a, 16b provided on the connecting portion 8 and the support portion 5.

[0059] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, as in a first modification shown in FIG. 6 , the second wiring 31 may be electrically connected to the first wiring 21 at a first connection portion 33 located at an end of the support portion 5. In the first modification, the second wiring 31 is provided on an insulating layer 51. An insulating layer 52 is provided on the insulating layer 51 so as to cover the second wiring 31. The insulating layer 52 has a first opening 52a that exposes a surface 33a of the first connection portion 33 opposite the support portion 5. The insulating layer 52 covers a corner 33b of the first connection portion 33. A region 53d of the surface of the insulating layer 52 opposite the support portion 5, corresponding to the corner 25b, is curved convexly toward the opposite side of the support portion 5. The first wiring 21 is provided on the insulating layer 52. The tip of the second portion 23 of the first wiring 21 extends over the first connection portion 33 so as to cover the first opening 52a. A part 23a of the second portion 23 is disposed within the first opening 52a and is connected to the surface 33a of the first connection portion 33 at the first opening 52a. As in the above embodiment, this first modification also makes it possible to suppress deterioration of the wiring 16a, 16b provided on the coupling portion 8 and the support portion 5. Furthermore, as in the first modification, the third wiring 41 may be electrically connected to the first wiring 21 at the second connection portion 26 located at the end portion on the movable portion 6.

[0060] As in a second modified example shown in FIG. 7 , a diffusion layer 58 may be provided instead of the insulating layer 51. The diffusion layer 58 is provided in a region on the surfaces of the support portion 5, the movable portion 6, and the pair of connecting portions 8 that contacts the first wiring 21. The diffusion layer 58 is, for example, a diffusion region formed by diffusing p-type impurities into the surface of an n-type silicon substrate. This second modified example also suppresses deterioration of the wirings 16a and 16b provided on the connecting portion 8 and the support portion 5, as in the above embodiment. Furthermore, according to the second modified example, the diffusion layer 58 functions as part of the first wiring 21, thereby ensuring insulation at the diffusion layer 58 and reducing the resistance of the wirings 16a and 16b provided on the connecting portion 8 and the support portion 5. Furthermore, when the first metal material is tungsten, tungsten easily adheres to the diffusion layer 58, allowing the first wiring 21 to be stably provided on the connecting portion 8.

[0061] As in a third modified example shown in Fig. 8, the width of the end 8b of each connecting portion 8 on the support portion 5 side may increase as it approaches the support portion 5. In Fig. 8, the boundary B between the connecting portion 8 and the support portion 5 and the boundary B between the connecting portion 8 and the movable portion 6 are indicated by two-dot chain lines. As in the above embodiment, this third modified example also makes it possible to suppress deterioration of the wiring 16a, 16b provided on the connecting portion 8 and the support portion 5.

[0062] In the above embodiment, the first wiring 21, the second wiring 31, and the third wiring 41 may be provided not only on the connecting portion 8 but also on the connecting portion 7. In this case, the first wiring 21 is provided on the connecting portion 7, the second wiring 31 is provided on the frame portion 4 and electrically connected to the electrodes 15a, 15b or the electrodes 17a, 17b, and the third wiring 41 is provided on the support portion 5 and electrically connected to the coil 11 or the second wiring 31 in the above embodiment. The connecting portion 7 may be linear. The connecting portion 8 may have any shape as long as it connects the movable portion 6 to the support portion 5 on the second axis X2 so that the movable portion 6 can swing about the second axis X2.

[0063] In the above embodiment, the insulating layer 52 is provided over the frame portion 4, the support portion 5, the movable portion 6, the pair of connecting portions 7, and the pair of connecting portions 8. However, it is sufficient that the insulating layer 52 is provided so as to be interposed at least between the first wiring 21 and the second wiring 31 or the third wiring 41. The shapes of the first opening 52a and the second opening 52b are not limited to circular. The first opening 52a and the second opening 52b may have, for example, a rectangular or diamond shape. Furthermore, the first opening 52a and the second opening 52b may have, for example, a notch shape that is open in the extension direction of the second portion 23 or the third portion 24.

[0064] A portion of the first opening 52a may be in contact with the corner 25b of the first connection portion 25. With this configuration, the corner 25b is also covered by the insulating layer 52, thereby reducing the stress acting from the first wiring 21 to the second wiring 31, as in the above embodiment. A portion of the second opening 52b may be in contact with the corner 26b of the second connection portion 26. With this configuration, the corner 26b is also covered by the insulating layer 52, thereby reducing the stress acting from the first wiring 21 to the second wiring 31, as in the above embodiment. A region of the surface of the insulating layer 52 opposite the support portion 5 that corresponds to the corner 25b does not have to be convexly curved and may be, for example, flat. With this configuration, the stress acting from the first wiring 21 to the second wiring 31 can be reduced, as in the above embodiment. A region of the surface of the insulating layer 52 opposite the movable portion 6 that corresponds to the corner 26b does not have to be convexly curved and may be, for example, flat. With this configuration, the stress acting from the first wiring 21 to the second wiring 31 can be reduced, similar to the above embodiment.

[0065] The first connection portion 25 may be a predetermined distance from the second axis X2, but may not be a distance D1 greater than half the minimum width W0 of the coupling portion 8. Similarly, the second connection portion 26 may be a predetermined distance from the second axis X2, but may not be a distance D2 greater than half the minimum width W0 of the coupling portion 8. The second wiring 31 may not be provided with the widened portion 32, and the third wiring 41 may not be provided with the widened portion 42. The third wiring 41 may be electrically connected to the coil 12 via another member made of a metal material.

[0066] In the first wiring 21, the first portion 22 and the second portion 23 or the third portion 24 may intersect at an angle other than perpendicular. Alternatively, the entire first wiring 21 may extend straight along the extension direction of the coupling portion. In this case, the first connection portion 25 is located on the second axis X2. The first portion 22, the second portion 23, and the third portion 24 may not have the same width. In this case, the width of the first wiring 21 refers to the minimum width or maximum width of the first portion 22, the second portion 23, and the third portion 24.

[0067] As long as the cross-sectional area of ​​the first wiring 21 is larger than the cross-sectional area of ​​the second wiring 31, the width W1 of the first wiring 21 may be smaller than the width W2 of the second wiring 31. For example, the thickness of the first wiring 21 may be larger than the thickness of the second wiring 31, and thus the cross-sectional area of ​​the first wiring 21 may be larger than the cross-sectional area of ​​the second wiring 31. However, the above embodiment is preferable in that it can prevent interference with twisting of the connecting portion 8 and can facilitate manufacturing. Similarly, as long as the cross-sectional area of ​​the first wiring 21 is larger than the cross-sectional area of ​​the third wiring 41, the width W1 of the first wiring 21 may be smaller than the width W3 of the third wiring 41. The cross-sectional area of ​​the first wiring 21 may be equal to or smaller than the cross-sectional area of ​​the second wiring 31 or the third wiring 41.

[0068] The actuator device 1 may also drive something other than the mirror 2. The shape of the mirror 2 is not limited to a circular shape. The mirror 2 may have, for example, a rectangular or diamond shape. In the above embodiment, the mirror 2 is oscillated (driven) by electromagnetic force, but it may also be oscillated by, for example, a piezoelectric element. In this case, wiring for applying a voltage to the piezoelectric element is provided instead of the coils 11 and 12. The magnetic field generating unit 3 may be omitted.

[0069] The first axis X1 and the second axis X2 do not have to be perpendicular to each other, as long as they intersect. The actuator device 1 may be one that swings only around the second axis X2. In this case, the frame portion 4 and the connecting portion 7 may be omitted, and electrodes for electrical connection with a control circuit, etc. may be provided on the support portion 5. The connecting portion 8 may be a region whose width is twice the minimum width W0. Alternatively, the connecting portion 8 may be a region whose stress acting when the movable portion 6 swings relative to the support portion 5 is half the maximum stress. [Explanation of symbols]

[0070] 1...actuator device, 2...mirror, 3...magnetic field generating section, 4...frame section, 5...support section, 6...movable section, 8...connecting section, 12...coil, 21...first wiring, 25, 33...first connection section, 25a, 33a...surface, 25b, 33b...corner, 26...second connection section, 26a...surface, 26b...corner, 31...second wiring, 41...third wiring, 52...insulating layer, 52a...first opening, 52b...second opening.

Claims

1. A support part; A movable part; a first connecting portion that connects the movable portion to the support portion on a predetermined axis so that the movable portion can swing around the axis; a first wiring provided in the first connecting portion; a third wiring provided on the movable portion; a first insulating layer having a second opening exposing a surface of one of the first wiring and the third wiring, the surface being opposite to the movable portion, at a second connection portion located at the movable portion; a second insulating layer covering the first wiring and the third wiring, the other of the first wiring and the third wiring is connected to the surface of the second connection portion in the second opening, a region of the surface of the second insulating layer opposite to the movable portion, the region corresponding to a corner of the other of the first wiring and the third wiring, is curved in a convex shape toward the opposite side of the movable portion, An actuator device, wherein a total length of the first wirings is longer than a total length of the third wirings.

2. A support part; A movable part; a first connecting portion that connects the movable portion to the support portion on a predetermined axis so that the movable portion can swing around the axis; a first wiring provided in the first connecting portion; a third wiring provided on the movable portion; a first insulating layer having a second opening exposing a surface of one of the first wiring and the third wiring, the surface being opposite to the movable portion, at a second connection portion located at the movable portion; a second insulating layer covering the first wiring and the third wiring; a first connecting part, separate from the first connecting part, that connects the movable part to the support part on the side opposite to the first connecting part on the axis so that the movable part can swing around the axis; a first wiring provided in the other first coupling portion and different from the first wiring; a third wiring provided on the movable portion and separate from the third wiring, the other of the first wiring and the third wiring is connected to the surface of the second connection portion in the second opening, a region of the surface of the second insulating layer opposite to the movable portion, the region corresponding to a corner of the other of the first wiring and the third wiring, is curved in a convex shape toward the opposite side of the movable portion, When a connection portion of one of the different first wiring and the different third wiring that is located at the movable portion is defined as a second connection portion that is different from the second connection portion, the first insulating layer has a second opening separate from the second opening, which exposes a surface of the other second connection portion opposite to the movable portion; An actuator device, wherein the other of the separate first wiring and the separate third wiring is connected to the surface of the separate second connection portion at the separate second opening.

3. A support part; A movable part; a first connecting portion that connects the movable portion to the support portion on a predetermined axis so that the movable portion can swing around the axis; a first wiring provided in the first connecting portion; a third wiring provided on the movable portion; a first insulating layer having a second opening exposing a surface of one of the first wiring and the third wiring, the surface being opposite to the movable portion, at a second connection portion located at the movable portion; a second insulating layer covering the first wiring and the third wiring; A frame portion and a second connecting portion that connects the support portion to the frame portion on another axis line that intersects with the axis line so that the support portion can swing around the another axis line, the other of the first wiring and the third wiring is connected to the surface of the second connection portion in the second opening, An actuator device, wherein a region of the surface of the second insulating layer opposite the movable portion corresponding to the corner of the other of the first wiring and the third wiring is convexly curved toward the opposite side of the movable portion.

4. A support part; A movable part; a first connecting portion that connects the movable portion to the support portion on a predetermined axis so that the movable portion can swing around the axis; a first wiring provided in the first connecting portion; a third wiring provided on the movable portion; a first insulating layer having a second opening exposing a surface of one of the first wiring and the third wiring, the surface being opposite to the movable portion, at a second connection portion located at the movable portion; a second insulating layer covering the first wiring and the third wiring, the other of the first wiring and the third wiring is connected to the surface of the second connection portion in the second opening, a region of the surface of the second insulating layer opposite to the movable portion, the region corresponding to a corner of the other of the first wiring and the third wiring, is curved in a convex shape toward the opposite side of the movable portion, An actuator device, wherein a width of the end of the first connecting portion on the movable portion side increases as it approaches the movable portion.

5. 5. An actuator device according to claim 1, wherein one of the first wiring and the third wiring is the first wiring, and the other of the first wiring and the third wiring is the third wiring.

6. 5. An actuator device according to claim 1, wherein one of the first wiring and the third wiring is the third wiring, and the other of the first wiring and the third wiring is the first wiring.

7. Further comprising a coil provided on the movable part, An actuator device as described in any one of claims 1 to 6, wherein the movable part has a groove portion having a shape corresponding to the coil, the coil is disposed within the groove portion, and is electrically connected to the first wiring and the third wiring.

8. 8. The actuator device according to claim 1, wherein the first wiring is provided across the support portion, the first connecting portion, and the movable portion.

9. 9. The actuator device according to claim 1, wherein the movable portion has a frame portion connected to the first connecting portion and an arrangement portion arranged inside the frame portion, and a mirror is arranged in the arrangement portion.

10. The actuator device according to claim 3 , wherein the first connecting portion has a straight shape and the second connecting portion has a serpentine shape.

11. A support part; A movable part; a first connecting portion that connects the movable portion to the support portion on a predetermined axis so that the movable portion can swing around the axis; a first wiring provided in the first connecting portion; a second wiring provided on the support portion; a first insulating layer having a first opening exposing a surface of one of the first wiring and the second wiring, the surface being opposite to the support portion at a first connection portion located on the support portion; a second insulating layer covering the first wiring and the second wiring, the other of the first wiring and the second wiring is connected to the surface of the first connection portion in the first opening, An actuator device, wherein a region of the surface of the second insulating layer opposite the support portion, which corresponds to the corner of the other of the first wiring and the second wiring, is convexly curved toward the opposite side of the support portion.

12. The actuator device according to claim 11 , wherein the one of the first wiring and the second wiring is the first wiring, and the other of the first wiring and the second wiring is the second wiring.

13. The actuator device according to claim 11 , wherein the one of the first wiring and the second wiring is the second wiring, and the other of the first wiring and the second wiring is the first wiring.

14. Further comprising a coil provided on the movable part, An actuator device as described in any one of claims 11 to 13, wherein the movable part is provided with a groove portion having a shape corresponding to the coil, the coil is disposed in the groove portion, and is electrically connected to the first wiring and the second wiring.

15. 15. The actuator device according to claim 11, wherein the first wiring is provided across the support portion, the first connecting portion, and the movable portion.

16. 16. The actuator device according to claim 11, wherein a total length of the second wirings is longer than a total length of the first wirings.

17. 17. The actuator device according to claim 11, wherein the movable portion has a frame portion connected to the first connecting portion and an arrangement portion arranged inside the frame portion, and a mirror is arranged in the arrangement portion.

18. a first connecting part, separate from the first connecting part, that connects the movable part to the support part on the side opposite to the first connecting part on the axis so that the movable part can swing around the axis; a first wiring provided in the other first coupling portion and different from the first wiring; a second wiring provided on the support portion and separate from the second wiring, When a connection portion of one of the other first wiring and the other second wiring that is located on the support portion is defined as a first connection portion that is different from the first connection portion, the first insulating layer has a first opening separate from the first opening, exposing a surface of the other first connection portion opposite to the support portion; An actuator device according to any one of claims 11 to 17, wherein the other of the separate first wiring and the separate second wiring is connected to the surface of the separate first connection portion at the separate first opening.

19. A frame portion and 19. The actuator device according to claim 11, further comprising: a second connecting portion that connects the support portion to the frame portion on another axis line that intersects with the axis line so that the support portion can swing around the other axis line.

20. 20. The actuator device according to claim 19, wherein the first connecting portion has a straight shape and the second connecting portion has a serpentine shape.

21. The actuator device according to any one of claims 11 to 20, wherein a width of the end of the first connecting portion on the support portion side increases as it approaches the support portion.

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