Patent Publication Number: US-10759655-B2

Title: Actuator device

Description:
TECHNICAL FIELD 
     The present disclosure relates to an actuator device configured as, for example, a micro electro mechanical systems (MEMS) device. 
     BACKGROUND ART 
     As an MEMS device, there is known an actuator device including a support portion, a movable portion, a connection portion connecting the movable portion to the support portion on a predetermined axis so that the movable portion is swingable about the axis, and wirings provided on the connection portion and the support portion. In such an actuator device, for example, there are cases where the movable portion is oscillated at a high speed corresponding to a resonance frequency level (several kHz to several tens of kHz). In such a case, because metal fatigue occurs in the wiring on the connection portion, there is concern that characteristics may be deteriorated and disconnection may occur. 
     In order to solve the above-described problems, there is proposed a technique in which a first wiring formed of a high-rigid metal material is provided on a connection portion and the first wiring is electrically connected to a second wiring formed of a low-rigid metal material in a low-stress region on a support portion (for example, see Patent Literature 1). 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: U.S. Pat. No. 8,218,218 
     SUMMARY OF INVENTION 
     Technical Problem 
     The present inventor has found that it is possible to further suppress deterioration of wirings provided on the connection portion and the support portion by contriving an electric connection structure between the first wiring and the second wiring in addition to disposing the electric connection position between the first wiring and the second wiring on the support portion. 
     An object of an embodiment of the present disclosure is to provide an actuator device capable of suppressing deterioration of wirings provided on a connection portion and a support portion. 
     Solution to Problem 
     An actuator device according to an embodiment of the present disclosure includes a support portion; a movable portion; a connection portion which connects the movable portion to the support portion on a predetermined axis so that the movable portion is swingable about the axis; a first wiring which is provided on the connection portion; and a second wiring which is provided on the support portion, in which rigidity of a first metal material forming the first wiring is higher than rigidity of a second metal material forming the second wiring, and in which the second wiring is connected to a surface opposite to the support portion in the first connection part located on the support portion in the first wiring. 
     In the actuator device, the rigidity of the first metal material forming the first wiring provided on the connection portion is higher than the rigidity of the second metal material forming the second wiring provided on the support portion. Accordingly, deterioration of the first wiring provided on the connection portion is suppressed. Also, deformation (curving or the like) of the support portion caused when all of the wirings provided on the connection portion and the support portion are formed of a high-rigid metal material is also suppressed. Further, the first wiring and the second wiring are connected to each other at the first connection part located on the support portion. Accordingly, because stress applied to the first connection part is reduced, deterioration of the first connection part is suppressed. Further, the second wiring is connected to the first wiring of the surface opposite to the support portion in the first connection part. Accordingly, because stress applied from the first wiring to the second wiring is released to the opposite side to the support portion, deterioration of the second wiring formed of the second metal material having rigidity lower than that of the first metal material is suppressed. Thus, according to the actuator device, it is possible to suppress deterioration of the wirings provided on the connection portion and the support portion. 
     In the actuator device according to an embodiment of the present disclosure, the first connection part may be separate from the axis by a predetermined distance. According to this configuration, it is possible to suppress stress applied to the first connection part while securing a region for providing another configuration on the support portion. 
     In the actuator device according to an embodiment of the present disclosure, the distance may be larger than ½ times a minimum width of the connection portion. According to this configuration, it is possible to further reduce stress applied to the first connection part while securing a region for providing another configuration on the support portion. 
     In the actuator device according to an embodiment of the present disclosure, a cross-sectional area of the first wiring may be larger than a cross-sectional area of the second wiring. According to this configuration, it possible to suppress an increase in resistance value of the first wiring even when the resistivity of the first metal material is higher than that of the second metal material. 
     In the actuator device according to an embodiment of the present disclosure, a width of the first wiring may be larger than a width of the second wiring. According to this configuration, it is possible to suppress an increase in resistance value of the first wiring by securing the cross-sectional area of the first wiring while suppressing the torsion of the connection portion from being obstructed. 
     The actuator device according to an embodiment of the present disclosure further includes a coil which is provided with the movable portion; a magnetic field generator which applies a magnetic field to the coil; and a third wiring which is provided on the movable portion and is electrically connected to the coil, in which the rigidity of the first metal material may be higher than that of a third metal material forming the third wiring and the third wiring may be connected to a surface opposite to the movable portion in the second connection part located on the movable portion in the first wiring. According to this configuration, it is possible to suppress deterioration of the wirings provided on the connection portion and the movable portion. 
     The actuator device according to an embodiment of the present disclosure may further include a frame which supports the support portion and the movable portion, in which the support portion is connected to the frame to be swingable about an axis intersecting the axis. According to this configuration, it is possible to swing the movable portion about each of two orthogonal axes. 
     The actuator device according to an embodiment of the present disclosure may further include a mirror which is provided with the movable portion. According to this configuration, it is possible to use the mirror for the light scanning or the like by swinging the mirror about the axis. 
     Advantageous Effects of Invention 
     According to an embodiment of the present disclosure, it is possible to suppress deterioration of the wirings provided on the connection portion and the support portion. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view of an actuator device according to an embodiment of the present disclosure. 
         FIG. 2  is a plan view of a circuit configuration of the actuator device of  FIG. 1 . 
         FIG. 3  is a partially enlarged view of  FIG. 2 . 
         FIG. 4  is a cross-sectional view taken along a line IV-IV of  FIG. 3 . 
         FIG. 5  is a cross-sectional view taken along a line V-V of  FIG. 3 . 
         FIG. 6  is a cross-sectional view of a first connection part of an actuator device of a first modified example. 
         FIG. 7  is a cross-sectional view of a first connection part of an actuator device of a second modified example. 
         FIG. 8  is a partially enlarged view of an actuator device of a third modified example. 
     
    
    
     DESCRIPTION OF EMBODIMENT 
     Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. In the following description, the same reference numerals will be used for the same or corresponding components and a repetitive description will be omitted. 
     As illustrated in  FIGS. 1 and 2 , an actuator device  1  includes a mirror  2 , a magnetic field generator  3 , a frame  4 , a support portion  5 , a movable portion  6 , a pair of connection portions  7 , and a pair of connection portions  8 . The actuator device  1  is configured as an MEMS device which swings the mirror  2  about each of a first axis X 1  and a second axis X 2  which are orthogonal to each other. Such an actuator device  1  is used in, for example, an optical switch or optical scanner. 
     The mirror  2  is a light reflection film formed by a metal film. The mirror  2  has a circular shape in the plan view (when viewed from a direction orthogonal to a plane in which at least the support portion  5 , the movable portion  6 , and the pair of connection portions  7  are arranged). A metal material forming the mirror  2  is, for example, aluminum (Al), gold (Au), or silver (Ag). 
     The magnetic field generator  3  is a rectangular flat plate and includes a pair of main surfaces. The magnetic field generator  3  applies a magnetic field to a coil  11  provided with the support portion  5  and a coil  12  provided with the movable portion  6  (the coils  11  and  12  will be described later). The magnetic field generator  3  is configured as, for example, a permanent magnet or the like. The array of the magnetic poles of the magnetic field generator  3  is, for example, a Halbach array. 
     The frame  4  is a flat plate-shaped frame having a rectangular shape in the plan view. The frame  4  is disposed on one main surface of the magnetic field generator  3 . The frame  4  supports the support portion  5 , the movable portion  6 , and the mirror  2  via the pair of connection portions  7 . Each connection portion  7  connects the support portion  5  to the frame  4  on the first axis X 1  so that the support portion  5  is swingable about the first axis X 1 . That is, each connection portion  7  serves as a torsion bar. Each connection portion  7  is formed in an S-shape in the plan view in order to improve the strength and facilitate the adjustment of the torsion spring constant. 
     The support portion  5  is a flat plate-shaped frame having a rectangular shape in the plan view and is located at the inside of the frame  4 . The support portion  5  is disposed to face one main surface of the magnetic field generator  3  and to be separate from one main surface of the magnetic field generator  3 . The support portion  5  supports the movable portion  6  and the mirror  2  via the pair of connection portions  8 . Each connection portion  8  connects the movable portion  6  to the support portion  5  on the second axis X 2  so that the movable portion  6  is swingable about the second axis X 2 . That is, each connection portion  8  serves as a torsion bar. 
     As illustrated in  FIG. 3 , each connection portion  8  is a flat plate-shaped member having a substantially rectangular shape in the plan view and extends along the second axis X 2 . An end  8   a  on the side of the movable portion  6  in each connection portion  8  increases in width as it approaches the movable portion  6 . Here, the width of the connection portion  8  means the length of the connection portion  8  in a direction orthogonal to the second axis X 2  in the plan view. When the connection portion  8  increases in width in at least one end and is connected to the support portion  5  or the movable portion  6 , the connection portion  8  is, for example, a region until the width becomes 1.5 times a minimum width W 0 . In  FIG. 3 , a boundary B between the connection portion  8  and the support portion  5  and a boundary B between the connection portion  8  and the movable portion  6  are indicated by a two-dotted chain line. The connection portion  8  may be a region where the stress applied during the swing of the movable portion  6  with respect to the support portion  5  is larger than ⅔ times the maximum stress. 
     As illustrated in  FIGS. 1 and 2 , the movable portion  6  is a flat plate-shaped frame having a rectangular shape in the plan view and is located at the inside of the support portion  5 . The movable portion  6  is disposed to face one main surface of the magnetic field generator  3  and to be separate from one main surface of the magnetic field generator  3 . An arrangement portion  9  having a circular shape in the plan view is provided at the inside of the movable portion  6 . The mirror  2  is disposed on the arrangement portion  9 . That is, the mirror  2  is provided with the movable portion  6 . The frame  4 , the support portion  5 , the movable portion  6 , the pair of connection portions  7 , and the pair of connection portions  8  are integrally formed of, for example, silicon (Si). 
     The actuator device  1  further includes, as illustrated in  FIG. 2 , the coil  11  provided with the support portion  5  and the coil  12  provided with the movable portion  6 . The coil  11  is buried in the support portion  5  and the coil  12  is buried in the movable portion  6 . Each of the coils  11  and  12  is formed of, for example, a metal material such as copper (Cu). In  FIG. 2 , each wiring is indicated by a solid line in order to facilitate understanding, but the wirings like the coils  11  and  12  are covered by an insulation layer  52  and/or an insulation layer  53  which will be described later. 
     The coil  11  is wound a plurality of turns in a spiral shape in the plan view. One end of a wiring  14   a  is electrically connected to an inner end of the coil  11 . One end of a wiring  14   b  is electrically connected to an outer end of the coil  11 . Each of the wirings  14   a  and  14   b  is formed of, for example, a metal material such as aluminum. Each of the wirings  14   a  and  14   b  is provided on one connection portion  7  and extends from the support portion  5  to the frame  4 . The other end of the wiring  14   a  is electrically connected to an electrode  15   a  provided with the support portion  5  and the other end of the wiring  14   b  is electrically connected to an electrode  15   b  provided with the support portion  5 . Each of the electrodes  15   a  and  15   b  is electrically connected to a control circuit or the like. The wiring  14   a  three-dimensionally intersects the coil  11  to pass over the coil  11 . 
     The coil  12  is wound a plurality of turns in a spiral shape in the plan view. One end of a wiring  16   a  is electrically connected to an inner end of the coil  12 . One end of a wiring  16   b  is electrically connected to an outer end of the coil  12 . Each of the wirings  16   a  and  16   b  is provided on the pair of connection portions  8 , the support portion  5 , and the other connection portion  7  and extends from the movable portion  6  to the frame  4 . The other end of the wiring  16   a  is electrically connected to an electrode  17   a  provided with the support portion  5  and the other end of the wiring  16   b  is electrically connected to an electrode  17   b  provided with the support portion  5 . Each of the electrodes  17   a  and  17   b  is electrically connected to a control circuit or the like. The wiring  16   a  three-dimensionally intersects the coil  12  to pass over the coil  12 . 
     Each of the wirings  16   a  and  16   b  includes a first wiring  21  provided on each connection 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 connection portion  8  will be described with reference to  FIGS. 3, 4, and 5 . Because the configurations of the first wiring  21  and the like in the vicinity of the other connection portion  8  are the same as the configurations of the first wiring  21  and the like in the vicinity of one connection portion  8 , a description thereof will be omitted. The insulation layer  52  (see  FIGS. 4 and 5 ) is omitted in  FIG. 3 . 
     The first wiring  21  is formed of a first metal material. The first wiring  21  is provided over the support portion  5 , the connection portion  8 , and the movable portion  6 . The first wiring  21  includes a first portion  22 , a second portion  23 , and a third portion  24 . The first portion  22  extends along the second axis X 2  on the support portion  5 , the connection portion  8 , and the movable portion  6 . The second portion  23  extends from an end on the side of the support portion  5  in the first portion  22  to the other connection portion  7  on the support portion  5 . The third portion  24  extends from an end on the side of the movable portion  6  in the first portion  22  to the one connection portion  7  on the movable portion  6 . The extension direction of the first portion  22  and the extension direction of the second portion  23  are orthogonal to each other and the extension direction of the first portion  22  and the extension direction of the third portion  24  are orthogonal to each other. 
     The first wiring  21  is electrically connected to the second wiring  31  in a first connection part  25  located at an end on the support portion  5 . The first wiring  21  is electrically connected to the third wiring  41  in a second connection part  26  located at an end on the movable portion  6 . The first connection part  25  is separate from the second axis X 2  by a predetermined distance D 1 . The distance D 1  is larger than ½ times the minimum width W 0  of the connection portion  8 . The second connection part  26  is separate from the second axis X 2  by a predetermined distance D 2 . The distance D 2  is larger than ½ times the minimum width W 0  of the connection portion  8 . The first portion  22 , the second portion  23 , and the third portion  24  have the same width. The width W 1  of the first wiring  21  is ½ times or more the minimum width W 0  of the connection portion  8  and is ⅔ times or more in this example. Here, the width W 1  of the first wiring  21  indicates the length of the first wiring  21  in a direction orthogonal to the extension direction of the first wiring  21  in the plan view. In the first portion  22 , the width indicates the length of the first portion  22  in a direction orthogonal to the second axis X 2  in the plan view. Additionally, the width W 1  of the first wiring  21  is, for example, about 50 to 100 μm. 
     The second wiring  31  is formed 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  17   a . A wide portion  32  which has a width larger than that of the other portion is provided at one end of the second wiring  31 . The second wiring  31  is electrically connected to the first connection part  25  of the first wiring  21  in the wide portion  32 . 
     The third wiring  41  is formed 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 . A wide portion  42  having a width larger than that of the other portion is provided at one end of the third wiring  41 . The third wiring  41  is electrically connected to the second connection part  26  of the first wiring  21  in the wide portion  42 . 
     The rigidity of the first metal material forming the first wiring  21  is higher than the rigidity of the second metal material forming the second wiring  31 . The rigidity of the first metal material forming the first wiring  21  is higher than the rigidity of the third metal material forming the third wiring  41 . In other words, the rigidity of the second metal material forming the second wiring  31  is lower than the rigidity of the first metal material forming the first wiring  21 . The rigidity of the third metal material forming the third wiring  41  is lower than the rigidity of the first metal material forming the first wiring  21 . Examples of a combination of the first metal material and the second metal material are a combination of tungsten (W) (the first metal material) and aluminum (the second metal material), a combination of tungsten (the first metal material) and copper (the second metal material), a combination of tungsten (the first metal material) and gold (the second metal material), and the like. Examples of a combination of the first metal material and the third metal material are a combination of tungsten (W) (the first metal material) and aluminum (the third metal material), a combination of tungsten (the first metal material) and copper (the third metal material), a combination of tungsten (the first metal material) and gold (the third metal material), and the like. The first metal material may be an aluminum alloy (AL-Cu or the like), nickel (Ni), platinum (Pt), or the like. 
     In the actuator device  1 , the width W 1  of the first wiring  21  is larger than each of the width W 2  of the second wiring  31  and the width W 3  of the third wiring  41 . The thickness of the first wiring  21  is the same as each of the thickness of the second wiring  31  and the thickness of the third wiring  41 . Thus, the cross-sectional area of the first wiring  21  is larger than each of the cross-sectional area of the second wiring  31  and the cross-sectional area of the third wiring  41 . Here, the width W 2  of the second wiring  31  means the length of the second wiring  31  (excluding the wide portion  32 ) in a direction orthogonal to the extension direction of the second wiring  31  in the plan view. The width W 3  of the third wiring  41  means the length of the third wiring  41  (excluding the wide portion  42 ) in a direction orthogonal to the extension direction of the third wiring  41  in the plan view. The cross-sectional area of the first wiring  21  means an area of a cross-section orthogonal to the extension direction of the first wiring  21 . The cross-sectional area of the second wiring  31  means an area of a cross-section orthogonal to the extension direction of the second wiring  31 . The cross-sectional area of the third wiring  41  means an area of a cross-section orthogonal to the extension direction of the third wiring  41 . Additionally, the width of the second wiring  31  is, for example, about 5 to 10 μm. 
     As illustrated in  FIG. 4 , the actuator device  1  further includes insulation layers  51 ,  52 , and  53 . Each of the insulation layers  51 ,  52 , and  53  is, for example, a silicon oxide film (SiO 2 ). 
     The insulation layer  51  is provided on the surfaces of the frame  4 , the support portion  5 , the movable portion  6 , the pair of connection portions  7 , and the pair of connection portions  8 . The first wiring  21  is provided on the insulation layer  51 . That is, the first wiring  21  is provided on the support portion  5  via the insulation layer  51 . 
     The insulation layer  52  is provided on the insulation layer  51  so as to cover the first wiring  21 . The insulation layer  52  is provided over the frame  4 , the support portion  5 , the movable portion  6 , the pair of connection portions  7 , and the pair of connection portions  8 . The insulation layer  52  includes a first opening  52   a  which exposes a surface  25   a  opposite to the support portion  5  in the first connection part  25 . The first opening  52   a  is a hole having a circular shape in the plan view. The first opening  52   a  is separate from a corner  25   b  of the first connection part  25  by a predetermined distance. The insulation layer  52  covers the corner  25   b  of the first connection part  25 . A region  53   d  corresponding to the corner  25   b  in the surface opposite to the support portion  5  in the insulation layer  52  is curved in a convex shape toward the opposite side of the support portion  5 . Here, the corner  25   b  of the first connection part  25  means a portion following an outer edge of the surface  25   a  in the first connection part  25  (i.e. a portion in which at least two surfaces of the first connection part  25  intersect each other). 
     The second wiring  31  is provided on the insulation layer  52 . That is, the second wiring  31  is provided on the support portion  5  via the insulation layers  51  and  52 . The wide portion  32  of the second wiring  31  runs on the first connection part  25  to cover the first opening  52   a . A part  32   a  of the wide portion  32  is disposed inside the first opening  52   a  and is connected to the surface  25   a  of the first connection part  25  in the first opening  52   a . The wide portion  32  includes a concave portion  32   b  at a position corresponding to the first opening  52   a  in the surface opposite to the support portion  5 . The concave portion  32   b  is formed such that a part  32   a  of the wide portion  32  enters the first opening  52   a  at the time of forming the second wiring  31 . 
     An electric connection structure between the first wiring  21  and the third wiring  41  is the same as the above-described electric connection structure between the first wiring  21  and the second wiring  31 . That is, as illustrated in  FIG. 3 , the insulation layer  52  includes a second opening  52   b  which exposes a surface  26   a  opposite to the movable portion  6  in the second connection part  26 . The second opening  52   b  is a hole having a circular shape in the plan view. The second opening  52   b  is separate from a corner  26   b  of the second connection part  26  by a predetermined distance. The insulation layer  52  covers the corner  26   b  of the second connection part  26 . A region corresponding to the corner  26   b  in the surface opposite to the movable portion  6  in the insulation layer  52  is curved in a convex shape toward the opposite side to the movable portion  6 . Here, the corner  26   b  of the second connection part  26  means a portion along an outer edge of the surface  26   a  of the second connection part  26  (i.e. a portion in which at least two surfaces of the second connection part  26  intersect each other). 
     The third wiring  41  is provided on the insulation layer  52 . That is, the third wiring  41  is provided on the movable portion  6  via the insulation layers  51  and  52 . The wide portion  42  of the third wiring  41  runs on the second connection part  26  to cover the second opening  52   b . A part of the wide portion  42  is disposed inside the second opening  52   b  and is connected to the surface  26   a  of the second connection part  26  in the second opening  52   b . The wide portion  42  includes a concave portion at a position corresponding to the second opening  52   b  in the surface opposite to the support portion  5 . The concave portion is formed such that a part of the wide portion  42  enters the second opening  52   b  at the time of forming the third wiring  41 . 
     The insulation layer  53  is provided on the insulation layer  52  to cover the second wiring  31  and the third wiring  41 . The insulation layer  53  is provided over the frame  4 , the support portion  5 , the movable portion  6 , the pair of connection portions  7 , and the pair of connection portions  8 . The insulation layer  53  includes a concave portion  53   a  at a position corresponding to the first opening  52   a  in the surface opposite to the support portion  5 . The concave portion  53   a  is formed such that a part of the insulation layer  53  enters the concave portion  32   b  at the time of forming the insulation layer  53 . The insulation layer  53  includes a concave portion at a position corresponding to the second opening  52   b  in the surface opposite to the support portion  5 . The concave portion of the insulation layer  53  is formed such that a part of the insulation layer  53  enters the concave portion of the wide portion  42  at the time of forming the insulation layer  53 . 
     As illustrated in  FIG. 5 , the movable portion  6  is provided with a groove portion  55  having a shape corresponding to the coil  12 . An inner surface of the groove portion  55  is provided with the insulation layer  51 . A seed layer  56  is provided on the insulation layer  51  inside the groove portion  55 . The seed layer  56  is formed of, for example, titanium nitride (TiN). The coil  12  is disposed inside the groove portion  55  via the insulation layer  51  and the seed layer  56 . The coil  12  is formed by burying, for example, a metal material such as copper in the groove portion  55  according to, for example, a damascene method. The insulation layer  52  is provided to cover the coil  12  disposed inside the groove portion  55 . The third wiring  41  is electrically connected to the coil  12  via an opening provided with the insulation layer  52  so that an inner end of the coil  12  is exposed. 
     A groove portion  13  is formed along the boundary between the seed layer  56  and the surface on the side of the insulation layer  52  in the coil  12  at the time of forming the coil  12 . The insulation layer  52  includes a groove portion  52   c  at a position corresponding to the groove portion  13  in the surface opposite to the movable portion  6 . The groove portion  52   c  is formed such that a part of the insulation layer  52  enters the groove portion  13  at the time of forming the insulation layer  52 . The third wiring  41  includes a groove portion  41   a  at a position corresponding to the groove portion  12   a  in the surface opposite to the movable portion  6 . The groove portion  41   a  is formed such that a part of the third wiring  41  enters the groove portion  52   c  at the time of forming the third wiring  41 . The insulation layer  53  includes a groove portion  53   b  at a position corresponding to the groove portion  12   a  in the surface opposite to the movable portion  6 . The groove portion  53   b  is formed such that a part of the insulation layer  53  enters the groove portion  41   a  at the time of forming the insulation layer  53 . 
     In the actuator device  1 , when a current flows to the coil  11 , a Lorentz force is generated in a predetermined direction by electrons flowing in the coil  11  by a magnetic field generated by the magnetic field generator  3 . Accordingly, the coil  11  receives a force in a predetermined direction. For this reason, it is possible to swing the support portion  5  about the first axis X 1  by controlling the direction or the magnitude of the current flowing in the coil  11 . Similarly, it is possible to swing the movable portion  6  about the second axis X 2  by controlling the direction or the magnitude of the current flowing in the coil  12 . Thus, it is possible to swing the mirror  2  about each of the first axis X 1  and the second axis X 2  which are orthogonal to each other by controlling the direction or the magnitude of the current flowing in the coil  11  and the coil  12 . Further, it is possible to swing the movable portion  6  at a high speed at the resonance frequency level by applying a current having a frequency corresponding to the resonance frequency of the movable portion  6  to the coil  12 . 
     In the above-described actuator device  1 , the rigidity of the first metal material forming the first wiring  21  provided on the connection portion  8  is higher than the rigidity of the second metal material forming the second wiring  31  provided on the support portion  5 . Accordingly, deterioration of the first wiring  21  provided on the connection portion  8  is suppressed. Also, it is possible to suppress the deformation (curving or the like) of the support portion  5  caused when the entire wiring provided on the connection portion  8  and the support portion  5  is formed of the first metal material having high rigidity. Further, the first wiring  21  and the second wiring  31  are connected to each other at the first connection part  25  located on the support portion  5 . Accordingly, stress applied to the first connection part  25  is reduced and deterioration of the first connection part  25  is suppressed. Further, in the actuator device  1 , the second wiring  31  is connected to the first wiring  21  in the surface  25   a  opposite to the support portion  5  in the first connection part  25 . Accordingly, because the stress applied from the first wiring  21  to the second wiring  31  is released to the opposite side to the support portion  5 , it is possible to suppress deterioration of the second wiring  31  formed of the second metal material having rigidity lower than that of the first metal material. That is, it is possible to prevent a problem in which the stress applied from the second wiring  31  to the first wiring  21  and the reaction force from the support portion  5  intensively act on the end of the second wiring  31 , which happens in a case in which the end of the second wiring  31  is interposed between the first wiring  21  and the support portion  5 . Thus, according to the actuator device  1 , it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5 . Further, because the first wiring  21  and the second wiring  31  are directly connected to each other, it is possible to reduce the resistance of the wirings provided on the connection portion  8  and the support portion  5 . 
     In the actuator device  1 , the first connection part  25  is separate from the second axis X 2  by a predetermined distance D. Accordingly, it is possible to reduce stress applied to the first connection part  25  while securing a region for providing another configuration (for example, the coil  11 ) on the support portion  5 . That is, it is possible to secure a region for providing another configuration on the support portion  5  compared to a case in which stress applied to the first connection part  25  is reduced by securing a distance along the second axis X 2  between the first connection part  25  and the connection portion  8 . 
     In the actuator device  1 , the distance D is larger than ½ times the minimum width W 0  of the connection portion  8 . Accordingly, it is possible to further reduce stress applied to the first connection part  25  while securing a region for providing another configuration on the support portion  5 . 
     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 . Accordingly, it is possible to suppress an increase in resistance value of the first wiring  21  even when the resistivity of the first metal material faulting the first wiring  21  is higher than the resistivity of the second metal material forming the second wiring  31 . 
     In the actuator device  1 , the width of the first wiring  21  is larger than the width of the second wiring  31 . Accordingly, it is possible to suppress an increase in resistance value of the first wiring  21  by securing the cross-sectional area of the first wiring  21  while suppressing the torsion of the connection portion  8  from being obstructed. 
     In the actuator device  1 , the rigidity of the first metal material forming the first wiring  21  provided on the connection portion  8  is higher than the rigidity of the third metal material forming the third wiring  41  provided on the movable portion  6 . Further, the first wiring  21  and the third wiring  41  are connected to each other in the second connection part  26  located on the movable portion  6 . Further, the corner  26   b  of the second connection part  26  is covered by the insulation layer  52  and the first wiring  21  and the third wiring  41  are connected to each other in the surface  26   a  opposite to the movable portion  6  in the second connection part  26  exposed by the second opening  52   b  of the insulation layer  52 . Thus, it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the movable portion  6 . 
     The actuator device  1  further includes the frame  4  which supports the support portion  5  and the movable portion  6  and the support portion  5  is connected to the frame  4  to be swingable about the first axis X 1  orthogonal to the second axis X 2 . Accordingly, it is possible to swing the movable portion  6  about each of two orthogonal axes. 
     The actuator device  1  further includes the mirror  2  provided with the movable portion  6 . Accordingly, it is possible to use the mirror  2  for the light scanning or the like by swinging the mirror about each of the first axis X 1  and the second axis X 2 . 
     In the actuator device  1 , the corner  25   b  of the first connection part  25  is covered by the insulation layer  52  and the first wiring  21  and the second wiring  31  are connected to each other in the surface  25   a  opposite to the support portion  5  in the first connection part  25  exposed by the first opening  52   a  of the insulation layer  52 . Accordingly, because stress applied from the first wiring  21  to the second wiring  31  is reduced by the insulation layer  52 , deterioration of the second wiring  31  formed of the second metal material of which the rigidity is lower than that of the first metal material is suppressed. Also with this configuration, according to the actuator device  1 , it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5 . 
     In the actuator device  1 , the first opening  52   a  is separate from the corner  25   b  of the first connection part  25 . Accordingly, it is possible to reliably reduce stress applied from the first wiring  21  to the second wiring  31 . 
     In the actuator device  1 , the region  53   d  corresponding to the corner  25   b  in the surface opposite to the support portion  5  in the insulation layer  52  is curved in a convex shape toward the opposite side to the support portion. Accordingly, it is possible to further reduce stress applied from the first wiring  21  to the second wiring  31 . 
     While an embodiment of the present invention has been described, the present invention is not limited to the above-described embodiment. For example, the first wiring  21  and the second wiring  31  may be connected to each other without the insulation layer  52  interposed therebetween similarly to the first modified example illustrated in  FIG. 6 . In the first modified example, the first wiring  21  is provided on the insulation layer  52 . The second wiring  31  is provided on the first wiring  21 . The wide portion  32  of the second wiring  31  runs on the first connection part  25 . The wide portion  32  is connected to the surface  25   a  of the first connection part  25 . Also in the first modified example, it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5  similarly to the above-described embodiment. Further, similarly to the first modified example, the first wiring  21  and the third wiring  41  may be connected to each other without the insulation layer  52  interposed therebetween. 
     Similarly to a second modified example illustrated in  FIG. 7 , a diffusion layer  58  may be provided instead of the insulation layer  51 . The diffusion layer  58  is provided with a region contacting the first wiring  21  on the surfaces of the support portion  5 , the movable portion  6 , and the pair of connection portions  8 . The diffusion layer  58  is, for example, a diffusion region formed by diffusing a p-type impurity on a surface of an n-type silicon substrate. Also in the second modified example, it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5  similarly to the above-described embodiment. Further, according to the second modified example, because the diffusion layer  58  serves as a part of the first wiring  21 , it is possible to reduce the resistance of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5  while securing the insulation at the diffusion layer  58 . Further, when the first metal material is tungsten, the first wiring  21  can be stably provided on the connection portion  8  because tungsten easily adheres to the diffusion layer  58 . 
     Similarly to a third modified example illustrated in  FIG. 8 , an end  8   b  on the side of the support portion  5  in each connection portion  8  may increase in width as it approaches the support portion  5 . In  FIG. 8 , a boundary B between the connection portion  8  and the support portion  5  and a boundary B between the connection portion  8  and the movable portion  6  are indicated by a two-dotted chain line. Also in the third modified example, it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5  similarly to the above-described embodiment. 
     In the above-described embodiment, the first wiring  21 , the second wiring  31 , and the third wiring  41  may be provided with the connection portion  7  as well as the connection portion  8 . In this case, the first wiring  21  is provided on the connection portion  7  and the second wiring  31  is provided on the frame  4  to be electrically connected to the electrodes  15   a  and  15   b  or the electrodes  17   a  and  17   b . Then, the third wiring  41  is provided on the support portion  5  to be electrically connected to the coil  11  or the second wiring  31  of the above-described embodiment. The connection portion  7  may have a linear shape. The connection portion  8  may have an arbitrary shape as long as the movable portion  6  is connected to the support portion  5  on the second axis X 2  so that the movable portion  6  is swingable about the second axis X 2 . 
     In the above-described embodiment, the insulation layer  52  is provided over the frame  4 , the support portion  5 , the movable portion  6 , the pair of connection portions  7 , and the pair of connection portions  8 , but may be provided at least so as to be interposed between at least the first wiring  21  and the second wiring  31  or the third wiring  41 . The shapes of the first opening  52   a  and the second opening  52   b  are not limited to circular shapes. The first opening  52   a  and the second opening  52   b  may have, for example, a rectangular shape, a rhombic shape, or the like. The first opening  52   a  and the second opening  52   b  may have a notch shape opened in, for example, the extension direction of the second portion  23  or the third portion  24 . The insulation layer  52  may not be provided. 
     A part of the first opening  52   a  may contact the corner  25   b  of the first connection part  25 . Also with this configuration, because the corner  25   b  is covered by the insulation layer  52 , it is possible to reduce stress applied from the first wiring  21  to the second wiring  31  similarly to the above-described embodiment. A part of the second opening  52   b  may contact the corner  26   b  of the second connection part  26 . Also with this configuration, because the corner  26   b  is covered by the insulation layer  52 , it is possible to reduce stress applied from the first wiring  21  to the second wiring  31  similarly to the above-described embodiment. A region corresponding to the corner  25   b  in the surface opposite to the support portion  5  in the insulation layer  52  may not be curved in a convex shape and may be curved in, for example, a plane shape. Also with this configuration, it is possible to reduce stress applied from the first wiring  21  to the second wiring  31  similarly to the above-described embodiment. A region corresponding to the corner  26   b  in the surface opposite to the movable portion  6  in the insulation layer  52  may not be curved in a convex shape and may be curved in, for example, a plane shape. Also with this configuration, it is possible to reduce stress applied from the first wiring  21  to the second wiring  31  similarly to the above-described embodiment. 
     The first connection part  25  may be separate from the second axis X 2  by a predetermined distance and may not be separated therefrom by the distance D 1  larger than ½ times the minimum width W 0  of the connection portion  8 . Similarly, the second connection part  26  may be separate from the second axis X 2  by a predetermined distance and may not be separated therefrom by the distance D 2  larger than ½ times the minimum width W 0  of the connection portion  8 . The second wiring  31  may not be provided with the wide portion  32  and the third wiring  41  may not be provided with the wide portion  42 . The third wiring  41  may be electrically connected to the coil  12  via another member formed of a metal material. 
     In the first wiring  21 , the first portion  22  and the second portion  23  or the third portion  24  may intersect each other at an angle other than the perpendicular direction. Alternatively, the whole first wiring  21  may straightly extend along the extension direction of the connection portion. In this case, the first connection part  25  is located on the second axis X 2 . 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  means the minimum width or the maximum width of the first portion  22 , the second portion  23 , and the third portion  24 . 
     The cross-sectional area of the first wiring  21  may be larger than the cross-sectional area of the second wiring  31  and the width W 1  of the first wiring  21  may be smaller than the width W 2  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 . Here, the above-described embodiment is preferable in that the torsion of the connection portion  8  can be prevented and the manufacturing can be facilitated. Similarly, the cross-sectional area of the first wiring  21  may be larger than the cross-sectional area of the third wiring  41  and the width W 1  of the first wiring  21  may be smaller than the width W 3  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 . 
     The actuator device  1  may be used to drive an object other than the mirror  2 . The shape of the mirror  2  is not limited to the circular shape. The mirror  2  may have, for example, a rectangular shape, a rhombic shape, or the like. In the above-described embodiment, the swinging (driving) of the mirror  2  is performed by an electromagnetic force, but may be performed by, for example, a piezoelectric element. In this case, a wiring for applying a voltage to the piezoelectric element is provided instead of the coils  11  and  12 . The magnetic field generator  3  may be omitted. 
     The first axis X 1  and the second axis X 2  may not be orthogonal to each other and may intersect each other. The actuator device  1  may swing only about the second axis X 2 . In this case, the frame  4  and the connection portion  7  may be omitted and an electrode to be electrically connected to a control circuit or the like may be provided with the support portion  5 . The connection portion  8  may be a region until the width becomes 2 times the minimum width W 0 . Alternatively, the connection portion  8  may be a region where the stress applied during the swing of the movable portion  6  with respect to the support portion  5  is larger than ½ times the maximum stress. 
     In the above-described embodiment, the insulation layer  52  covers the entire corner  25   b  of the first connection part  25 , but may cover at least a part of the corner  25   b . For example, the insulation layer  52  may cover at least a portion of the corner  25   b  in the first connection part  25  where the surface  25   a  opposite to the support portion  5  intersects the surface (in the above-described embodiment, the surface on the side of the other connection portion  7 ) on the side to which the second wiring  31  is drawn out. Even when the insulation layer  52  covers only a portion in which the surface  25   a  opposite to the support portion  5  intersects the surface in which the second wiring  31  in the first connection part  25  is drawn in the corner  25   b , it is possible to suppress deterioration of the wirings  16   a  and  16   b  provided on the connection portion  8  and the support portion  5  similarly to the above-described embodiment. The second wiring  31  may be drawn along the second axis X 2  from, for example, the first connection part  25 . Similarly to the corner  26   b  of the second connection part  26 , the insulation layer  52  may cover at least a part of the corner  26   b.    
     REFERENCE SIGNS LIST 
       1  . . . actuator device,  2  . . . mirror,  3  . . . magnetic field generator,  4  . . . frame,  5  . . . support portion,  6  . . . movable portion,  8  . . . connection portion,  12  . . . coil,  21  . . . first wiring,  25  . . . first connection part,  25   a  . . . surface,  25   b  . . . corner,  26  . . . second connection part,  26   a  . . . surface,  26   b  . . . corner,  31  . . . second wiring,  41  . . . third wiring.