Patent Publication Number: US-11646170-B2

Title: MEMS element and electrical circuit

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2020-154739, filed on Sep. 15, 2020; the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments of the invention generally relate to a MEMS element and an electrical circuit. 
     BACKGROUND 
     For example, a MEMS (Micro Electro Mechanical Systems) element is used in a switch or the like. A stable operation of the MEMS element is desirable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 A and  1 B  are schematic views illustrating a MEMS element according to a first embodiment; 
         FIGS.  2 A and  2 B  are schematic plan views illustrating portions of the MEMS element according to the first embodiment; 
         FIGS.  3 A to  3 C  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment; 
         FIGS.  4 A and  4 B  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment; 
         FIG.  5    is a graph illustrating characteristics of the MEMS element; 
         FIG.  6    is a schematic plan view illustrating a portion of a MEMS element according to the first embodiment; 
         FIGS.  7 A and  7 B  are schematic views illustrating a MEMS element according to the first embodiment; 
         FIGS.  8 A to  8 C  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment; 
         FIGS.  9 A to  9 C  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment; 
         FIGS.  10 A and  10 B  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment; 
         FIGS.  11 A and  11 B  are schematic views illustrating a MEMS element according to a second embodiment; 
         FIGS.  12 A and  12 B  are graphs illustrating characteristics of the MEMS element; 
         FIG.  13    is a schematic plan view illustrating a MEMS element according to the second embodiment; 
         FIG.  14    is a schematic cross-sectional view illustrating a MEMS element according to the second embodiment; 
         FIG.  15    is a schematic view illustrating a MEMS element including multiple element parts according to a third embodiment; 
         FIG.  16    is a schematic view illustrating a control circuit used in the MEMS element according to the third embodiment; and 
         FIG.  17    is a schematic view illustrating a control circuit used in the MEMS element according to the third embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     According to one embodiment, a MEMS element includes a first member, and an element part. The element part includes a first fixed electrode fixed to the first member, a first movable electrode facing the first fixed electrode, a first conductive member electrically connected to the first movable electrode, and a second conductive member electrically connected to the first movable electrode. The first movable electrode is supported by the first and second conductive members to be separated from the first fixed electrode. The first conductive member has a meandering structure. The second conductive member includes a first conductive region and a second conductive region. The second conductive region is between the first movable electrode and the first conductive region. A second width of the second conductive region along a second direction is less than a first width of the first conductive region along the second direction. The second direction crosses a first direction from the first movable electrode toward the first conductive region. 
     According to one embodiment, a MEMS element includes a first member, and an element part. The element part includes a first fixed electrode fixed to the first member, a first movable electrode facing the first fixed electrode, a first conductive member electrically connected to the first movable electrode, and a second conductive member electrically connected to the first movable electrode. The first movable electrode is supported by the first and second conductive members to be separated from the first fixed electrode. The first movable electrode includes a second connection part connected with the first conductive member, and a first connection part connected with the second conductive member. A width of the first movable electrode along a second direction increases in an orientation from the first connection part toward the second connection part in at least a portion of the first movable electrode. The second direction crosses a first direction from the first connection part toward the second connection part. 
     According to one embodiment, an electrical circuit includes the MEMS dement described in any one of the MEMS elements described above, and an electrical element electrically connected to the MEMS dement. 
     Various embodiments are described below with reference to the accompanying drawings. 
     The drawings are schematic and conceptual; and the relationships between the thickness and width of portions, the proportions of sizes among portions, etc., are not necessarily the same as the actual values. The dimensions and proportions may be illustrated differently among drawings, even for identical portions. 
     In the specification and drawings, components similar to those described previously or illustrated in an antecedent drawing are marked with like reference numerals, and a detailed description is omitted as appropriate. 
     First Embodiment 
       FIGS.  1 A and  1 B  are schematic views illustrating a MEMS element according to a first embodiment. 
       FIGS.  2 A and  2 B  are schematic plan views illustrating portions of the MEMS element according to the first embodiment. 
       FIG.  1 A  is a plan view as viewed along arrow AR 1  of  FIG.  1 B .  FIG.  1 B  is a line A 1 -A 2  cross-sectional view of  FIG.  1 A . 
     As shown in  FIG.  1 B , the MEMS element  110  according to the embodiment includes a first member  41  and an element part  51 . The first member  41  is, for example, a base body. In the example, the first member  41  includes a substrate  41   s  and an insulating layer  41   i . The substrate  41   s  is, for example, a silicon substrate. The substrate  41   s  may include a control element such as a transistor, etc. The insulating layer  41   i  is located on the substrate  41   s . For example, the element part  51  is located on the insulating layer  41   i . According to the embodiment, the first member  41  may include interconnects, etc, (not illustrated). For example, the interconnects electrically connect the element part  51  and the substrate  41   s . The interconnects may include contact vias. 
     As shown in  FIGS.  1 A and  1 B , the element part  51  includes a first fixed electrode  11 , a first movable electrode  20 E, a first conductive member  21 , and a second conductive member  22 . The first fixed electrode  11  is fixed to the first member  41 . For example, the first fixed electrode  11  is located on the insulating layer  41   i.    
     The first movable electrode  20 E faces the first fixed electrode  11 . The first conductive member  21  is electrically connected to the first movable electrode  20 E. The second conductive member  22  is electrically connected to the first movable electrode  20 E. 
     As described below, for example, a first electrical signal Sg 1  (referring to  FIG.  1 B ) can be applied between the second conductive member  22  and the first fixed electrode  11 . The state before the first electrical signal Sg 1  is applied is taken to be a first state (e.g., an initial state).  FIGS.  1 A and  1 B  illustrate the first state. 
     As shown in  FIG.  1 B , the first movable electrode  20 E is supported by the first and second conductive members  21  and  22  to be separated from the first fixed electrode  11  in the first state. For example, a first gap g 1  is between the first fixed electrode  11  and the first movable electrode  20 E in the first state, 
     For example, a first supporter  21 S and a second supporter  22 S are provided. The first supporter  21 S and the second supporter  22 S are fixed to the first member  41 . The first supporter  21 S and the second supporter  22 S are, for example, conductive. 
     One end of the first conductive member  21  is connected to the first supporter  21 S. The first conductive member  21  is supported by the first supporter  21 S. The other end of the first conductive member  21  is connected to the first movable electrode  20 E. One end of the second conductive member  22  is connected to the second supporter  22 S. The second conductive member  22  is supported by the second supporter  22 S. The other end of the second conductive member  22  is connected to the first movable electrode  20 E. In the example, the first movable electrode  20 E is between the first supporter  21 S and the second supporter  22 S. The first conductive member  21  is between the first supporter  21 S and the first movable electrode  20 E. In the example, the second conductive member  22  is between the first movable electrode  20 E and the second supporter  22 S. 
     As shown in  FIG.  1 A , for example, the first conductive member  21  is fine-wire-shaped. In the example, the first conductive member  21  has a meandering structure. For example, the first conductive member  21  and the second conductive member  22  are spring members. 
     According to the embodiment as shown in  FIG.  1 A , the planar shape of the second conductive member  22  is different from the planar shape of the first conductive member  21 . 
       FIG.  2 A  is an enlarged illustration of the first conductive member  21 .  FIG.  2 B  is an enlarged illustration of the second conductive member  22 . 
     As shown in  FIGS.  1 A and  2 B , for example, the second conductive member  22  includes a first conductive region  22   a  and a second conductive region  22   b . The second conductive region  22   b  is between the first movable electrode  20 E and the first conductive region  22   a . The direction from the first movable electrode  20 E toward the first conductive region  22   a  is taken as a first direction. 
     The first direction is, for example, an X-axis direction. One direction perpendicular to the X-axis direction is taken as a Y-axis direction. A direction perpendicular to the X-axis direction and the Y-axis direction is taken as a Z-axis direction. For example, the direction from the first fixed electrode  11  toward the first movable electrode  20 E is along the Z-axis direction. One direction that crosses the first direction (the X-axis direction) is taken as a second direction Dp 2 . The second direction Dp 2  is, for example, the Y-axis direction. The second direction Dp 2  crosses a plane including the first direction (the X-axis direction) and the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E. 
     As shown in  FIG.  2 B , the width along the second direction Dp 2  (e.g., the Y-axis direction) of the second conductive member  22  is different by location. The width of the first conductive region  22   a  along the second direction Dp 2  (e.g., the Y-axis direction) is taken as a first width W 22   a . The width of the second conductive region  22   b  along the second direction Dp 2  is taken as a second width W 22   b . The second width W 22   b  is less than the first width W 22   a.    
     By such a configuration, as described below, a MEMS element can be provided in which a stable operation is possible. 
     For example, the widths of the first and second conductive members  21  and  22  are less than a width W 20  of the first movable electrode  20 E (referring to  FIG.  1 A ). The first conductive member  21  and the second conductive member  22  deform more easily than the first movable electrode  20 E. 
     For example, the distance (the length in the Z-axis direction) between the first fixed electrode  11  and the first movable electrode  20 E is changeable according to the potential difference between the first fixed electrode  11  and the first movable electrode  20 E. The first movable electrode  20 E is displaceable when referenced to the first fixed electrode  11 . 
     A first terminal T 1  and a second terminal T 2  may be provided as shown in  FIG.  1 B . The first terminal T 1  is electrically connected to the first conductive member  21 . The second terminal T 2  is electrically connected to the second conductive member  22 . For example, a current can flow between the first terminal T 1  and the second terminal T 2  in the first state. At this time, the MEMS element  110  is in a conducting state (e.g., an on-state). As described below, the first conductive member  21  and the second conductive member  22  can be broken. In such a case, a current does not flow between the first terminal T 1  and the second terminal T 2 . At this time, the MEMS element  110  is in a nonconducting state (e.g., an off-state). 
     In the on-state, for example, a current can flow in a first current path  21   cp  including the first conductive member  21  and the first movable electrode  20 E (referring to  FIG.  1 A ). In the on-state, for example, a current can flow in a second current path  22   cp  including the second conductive member  22  and the first movable electrode  20 E (referring to  FIG.  1 A ). 
     The MEMS element  110  can function as a normally-on switch element. 
     The element part  51  may include a first capacitance element  31  (referring to  FIG.  1 B ). For example, the first capacitance element  31  is electrically connected to the first conductive member  21 . In the example, the first capacitance element  31  is electrically connected to the first terminal T 1 . The electrical connection to the first capacitance element  31  can be controlled by controlling the on-state or the off-state of the element part  51 . 
     As shown in  FIG.  1 B , for example, a controller  70  may be provided. For example, the controller  70  is electrically connected to a first control terminal Tc 1  and the second terminal T 2 . The first control terminal Tc 1  is electrically connected to the first fixed electrode  11 . The first electrical signal Sgt can be applied between the second conductive member  22  and the first fixed electrode  11  by the controller  70 . The first electrical signal Sgt includes at least one of a voltage signal or a current signal. 
     For example, the potential of the second conductive member  22  (e.g., the potential of the second terminal T 2 ) is fixed, and the potential of the first fixed electrode  11  is controllable by the controller  70 . According to the embodiment, the potential of the first fixed electrode  11  may be substantially fixed, and the potential of the second conductive member  22  may be controllable by the controller  70 . Hereinbelow, one example will be described in which the potential of the second conductive member  22  (e.g., the potential of the second terminal T 2 ) is fixed. In such a case, the potential of the first fixed electrode  11  is controlled by the controller  70 . The polarity of the potential difference between the second conductive member  22  and the first fixed electrode  11  is arbitrary. 
     In the first state, the potential of the first movable electrode  20 E is substantially equal to the potential of the second conductive member  22 . The potential difference between the first fixed electrode  11  and the first movable electrode  20 E is changed by changing the potential of the first fixed electrode  11 . For example, the distance between the first movable electrode  20 E and the first fixed electrode  11  decreases as the potential difference increases. For example, this is based on an electrostatic force. When the potential difference becomes large, the first movable electrode  20 E contacts the first fixed electrode  11 ; and a current can flow in the conductive member via the first movable electrode  20 E and the first fixed electrode  11 . The conductive member can be broken thereby. The first state before breaking and the second state after breaking can be formed thereby. The phenomenon of the first movable electrode  20 E and the first fixed electrode  11  contacting is called “pull-in” or “pull-down”. The voltage that generates “pull-in” or “pull-down” is called the “pull-in voltage” or the “pull-down voltage”. 
     For example, the element part  51  of the MEMS element  110  can function as a OTP (One Time Programmable) element. 
     According to the embodiment as described above, the planar shape of the second conductive member  22  is different from the planar shape of the first conductive member  21 . For example, the first conductive member  21  is fine-wire-shaped and has a meandering structure. On the other hand, the second conductive member  22  includes the first conductive region  22   a  and the second conductive region  22   b  such as those described above. Because the planar shape of the second conductive member  22  is different from the planar shape of the first conductive member  21 , for example, the rigidity of the first conductive member  21  is less than the rigidity of the second conductive member  22 . For example, in such a configuration, the first movable electrode  20 E easily changes to a tilted state when the first movable electrode  20 E approaches the first fixed electrode  11 . The first conductive member  21  can be stably broken thereby, and subsequently, the second conductive member  22  can be stably broken. 
     An example of a transition from the first state to the second state will now be described. 
       FIGS.  3 A to  4 B  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment. 
     These drawings illustrate the change of the element part  51  when the first electrical signal Sg 1  is applied between the second conductive member  22  and the first fixed electrode  11 . As described above, the first electrical signal Sg 1  is supplied by the controller  70 . 
     In the first state ST 1  shown in  FIG.  3 A , the first electrical signal Sg 1  is not applied between the second conductive member  22  and the first fixed electrode  11 . For example, the second conductive member  22  and the first fixed electrode  11  are in a floating state FLT. At this time, the first movable electrode  20 E is separated from the first fixed electrode  11 . In such a first state ST 1 , a current can flow between the first terminal T 1  and the second terminal T 2 . The element part  51  is in the conducting state (the on-state) in the first state ST 1 . In the first state ST 1 , the potential difference between the second conductive member  22  and the first fixed electrode  11  may be less than the pull-in voltage. 
     As shown in  FIG.  3 B , for example, the second terminal T 2  (the second conductive member  22 ) is set to a ground potential V 0 ; and the first electrical signal Sgt is applied to the first fixed electrode  11 . Thereby, the first movable electrode  20 E is caused to approach the first fixed electrode  11 . For example, the first movable electrode  20 E tilts easily when the first conductive member  21  and the second conductive member  22  are asymmetric. For example, compared to an end portion  20 Eq at the second conductive member  22  side of the first movable electrode  20 E, an end portion  20 Ep at the first conductive member  21  side of the first movable electrode  20 E approaches the first fixed electrode  11 . An electric field concentrates at the end portion  20 Ep at the first conductive member  21  side of the first movable electrode  20 E and at an end portion  21   p  at the first movable electrode  20 E side of the first conductive member  21 . For example, the end portion  21   p  contacts the first fixed electrode  11 . For example, the end portion  20 Ep contacts the first fixed electrode  11 . Therefore, the temperature easily increases locally at the end portion  20 Ep and the end portion  21   p . For example, the increase of the temperature is due to Joule heat. 
     The first conductive member  21  breaks when the temperature of at least one of the end portion  20 Ep or the end portion  21   p  increases locally. As shown in  FIG.  3 B , a break portion  216  occurs in the first conductive member  21 . The first conductive member  21  is divided at the break portion  216 . 
     For example, as shown in  FIG.  1 A , a portion of the first conductive member  21  may overlap the first fixed electrode  11  in the Z-axis direction. For example, when a portion of the first conductive member  21  overlaps the first fixed electrode  11  in the Z-axis direction, the portion (the end portion  21   p ) of the first conductive member  21  easily contacts the first fixed electrode  11  when the first movable electrode  20 E approaches the first fixed electrode  11 . For example, a current locally flows between the first fixed electrode  11  and the portion (the end portion  21   p ) of the first conductive member  21 . The first conductive member  21  is more stably broken by the current concentrating at the portion (the end portion  21   p ) of the first conductive member  21 . For example, the mechanical rigidity of the first conductive member  21  is less than the mechanical rigidity of the first movable electrode  20 E. Thereby, the end portion  21   p  is easily caused to contact the first fixed electrode  11 . 
     As shown in  FIG.  3 C , the broken first conductive member  21  may approach the state of  FIG.  3 A . For example, this is due to the restoring force due to the elasticity of the first conductive member  21 . As shown in  FIG.  3 C , the end portion  20 Ep of the first movable electrode  20 E is separated from the first conductive member  21 . 
     As shown in  FIG.  4 A , substantially the entire first movable electrode  20 E may contact the first fixed electrode  11  when the application of the first electrical signal Sg 1  is continued. This state is, for example, the pull-down state. When the first movable electrode  20 E contacts the first fixed electrode  11 , there are cases where the first movable electrode  20 E is adhered to the first fixed electrode  11 ; and the first movable electrode  20 E substantially does not separate from the first fixed electrode  11 . 
     As shown in  FIG.  4 A , when the application of the first electrical signal Sg 1  is continued, the temperature of a portion (the second conductive region  22   b ) of the second conductive member  22  locally increases, and the second conductive member  22  breaks. For example, the increase of the temperature is due to Joule heat. As described above, the temperature of the second conductive region  22   b  easily increases locally because the second width W 22   b  of the second conductive region  22   b  is less than the first width W 22   a  of the first conductive region  22   a . Thereby, a break portion  22 B is stably caused to occur at the second conductive region  22   b  or the vicinity of the second conductive region  22   b . The second conductive member  22  is divided at the break portion  22 B. For example, the break portion  22 B is formed at the vicinity of the end portion of the second conductive member  22  at the first movable electrode  20 E side. The application of the first electrical signal Sg 1  ends. 
     Subsequently, as shown in  FIG.  4 B , the broken second conductive member  22  may approach the state of  FIG.  3 A . For example, this is due to the restoring force due to the elasticity of the second conductive member  22 . As shown in  FIG.  4 B , the end portion  20 Eq of the first movable electrode  20 E is separated from the second conductive member  22 . 
     A second state ST 2  shown in  FIG.  4 B  is a state after the first electrical signal Sg 1  is applied between the second conductive member  22  and the first fixed electrode  11 . For example, in the second state ST 2 , the first fixed electrode  11  is in, for example, the floating state FLT. The broken states of the first and second conductive members  21  and  22  continue even after the application of the first electrical signal Sg 1  has ended. A current does not flow between the first terminal T 1  and the second terminal T 2  in the second state ST 2 . The element part  51  is in the nonconducting state (the off-state) in the second state ST 2 . For example, in the second state ST 2 , the second conductive member  22  is in, for example, the floating state FLT. Or, in the second state ST 2 , the potential of the second conductive member  22  may have the potential of a circuit connected to the second conductive member  22 . 
     Thus, according to the embodiment, both the first conductive member  21  and the second conductive member  22  are in a broken state in the second state ST 2  after the first electrical signal Sgt is applied between the second conductive member  22  and the first fixed electrode  11 . The current that flows between the first terminal T 1  and the second terminal T 2  can be stably blocked thereby. 
     A reference example may be considered in which one of the first conductive member  21  or the second conductive member  22  is broken. For example, in a first reference example, the temperature of the end portion  20 Eq at the second conductive member  22  side of the first movable electrode  20 E becomes greater than the temperature of the end portion  20 Ep at the first conductive member  21  side of the first movable electrode  20 E when the first electrical signal Sgt is applied to the first fixed electrode  11 . For example, this is due to effects of the shapes, the thermal resistances, etc., of the first and second conductive members  21  and  22 . In such a case, the second conductive member  22  is broken by the Joule heat due to the current due to the first electrical signal Sg 1 . On the other hand, the other end (the first terminal T 1 ) of the first conductive member  21  is floating. Therefore, when the first electrical signal Sgt is applied to the first fixed electrode  11 , a current does not flow in the first conductive member  21 ; and the first conductive member  21  is not broken. In such a first reference example as well, the current that flows between the first terminal T 1  and the second terminal T 2  can be blocked. 
     In the first reference example after the second conductive member  22  is broken, the first terminal T 1  is electrically connected to the first fixed electrode  11  via the first conductive member  21  and the first movable electrode  20 E. For example, when a transistor that controls the application of the first electrical signal Sg 1  to the first fixed electrode  11  or the like is connected with the first fixed electrode  11 , the parasitic capacitance of the transistor remains even after the application of the first electrical signal Sg 1  has ended. The parasitic capacitance of the transistor affects the capacitance of the first terminal T 1 . In the first reference example, such an unnecessary capacitance remains in the element part  51 . The remaining capacitance easily causes unstable electrical characteristics of the off-state of the element part  51  functioning as a switch. For example, when the signal of the circuit in which the element part  51  is embedded has a high frequency, the remaining capacitance makes the characteristics of the element part  51  unstable. 
     According to the embodiment, the first conductive member  21  and the second conductive member  22  are in a broken state in the second state ST 2 . Therefore, the first terminal T 1  is separated from the first fixed electrode  11  and the parasitic capacitance of the transistor. The electrical characteristics of the element part  51  in the off-state are stabilized thereby. Stable off-characteristics can be maintained even for high frequency switching. According to the embodiment, a MEMS element can be provided in which a stable operation is possible. 
     According to the embodiment, for example, the first conductive member  21  breaks when the first electrical signal Sg 1  is applied between the second conductive member  22  and the first fixed electrode  11 . Continuing, the second conductive member  22  also is broken by continuing the application of the first electrical signal Sg 1 . Or, the application of the first electrical signal Sg 1  can be ended after the first conductive member  21  has broken and before the second conductive member  22  has broken. However, the first electrical signal Sg 1  may not be ended partway because the second conductive member  22  can be broken by continuing the application of the first electrical signal Sg 1 . 
     As shown in  FIG.  1 A , for example, a portion of the meandering structure of the first conductive member  21  may overlap an end portion lip of the first fixed electrode  11  in the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E. Thereby, breaking is easily caused to occur at the second conductive region  22   b  and the vicinity of the second conductive region  22   b.    
     As shown in  FIG.  1 A , for example, the second conductive region  22   b  overlaps an end portion  11   q  of the first fixed electrode  11  in the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E. Thereby, breaking is easily caused to occur at the second conductive region  22   b  and the vicinity of the second conductive region  22   b.    
     As shown in  FIG.  2 B , the length of the first conductive region  22   a  along the first direction (the X-axis direction) is taken as a length L 22   a . The length of the second conductive region  22   b  along the first direction (the X-axis direction) is taken as a length L 22   b . In the example, the length L 22   b  is less than the length L 22   a . By such a configuration, the second conductive member  22  can stably support the first movable electrode  20 E; and the temperature can be efficiently increased locally in the second conductive region  22   b.    
     As shown in  FIG.  2 A , the first conductive member  21  has a first length along the first current path  21   cp  including the first conductive member  21  and the first movable electrode  20 E. The first length corresponds to the sum of lengths L 21   a  to L 21   g . As shown in  FIG.  2 B , the second conductive member  22  has a second length along the second current path  22   cp  including the second conductive member  22  and the first movable electrode  20 E. For example, the second length corresponds to the sum of the length L 22   a  and the length L 22   b . In the example, the second length is less than the first length. In such a case, the rigidity of the first conductive member  21  is less than the rigidity of the second conductive member  22 . Therefore, the characteristics of the first conductive member  21  are asymmetric to the characteristics of the second conductive member  22 . 
     As shown in  FIG.  2 A , the first conductive member  21  has a width W 1  along a direction Dp 1  crossing the first current path  21   cp . The width W 1  is less than the width W 20  of the first movable electrode  20 E (referring to  FIG.  1 A ). As shown in  FIGS.  1 A and  2 B , the first width W 22   a  along a direction (the second direction Dp 2 ) crossing the second current path  22   cp  of the first conductive region  22   a  of the second conductive member  22  is less than the width W 20 . 
       FIG.  5    is a graph illustrating characteristics of the MEMS element. 
       FIG.  5    illustrates simulation results of the temperature increases of the first and second conductive members  21  and  22  when the first electrical signal Sg 1  is applied between the second conductive member  22  and the first fixed electrode  11 . In the simulation, the first conductive member  21  has the meandering structure illustrated in  FIGS.  1 A and  2 A . In the simulation, the first width W 22   a  of the first conductive region  22   a  of the second conductive member  22  is constant, and the second width W 22   b  of the second conductive region  22   b  of the second conductive member  22  is modified. The horizontal axis of  FIG.  5    is a ratio R 1  of the second width W 22   b  to the first width W 22   a . The vertical axis of  FIG.  5    is a temperature Tm.  FIG.  5    shows a temperature Tm 21   p  of the end portion  21   p  at the first movable electrode  20 E side of the first conductive member  21  and a temperature Tm 22   b  of the second conductive region  22   b  of the second conductive member  22 . 
     As shown in  FIG.  5   , the temperature Tm 22   b  of the second conductive region  22   b  increases as the ratio R 1  decreases. When the ratio R 1  is excessively high (e,g., when R 1  is 1), the increase of the temperature Tm 22   b  of the second conductive region  22   b  is insufficient, and it is difficult to break the second conductive region  22   b.    
     On the other hand, when the ratio R 1  is low, the temperature Tm 21   p  of the end portion  21   p  at the first movable electrode  20 E side of the first conductive member  21  decreases. Therefore, the end portion  21   p  does not easily break. 
     According to the embodiment, for example, the second width W 22   b  is not less than 0.1 times the first width W 22   a . For example, it is favorable for the second width W 22   b  to be not less than 0.25 times and not more than 0.7 times the first width W 22   a . The second width W 22   b  may be not less than 0.33 times and not more than 0.66 times the first width W 22   a . A sufficient increase of the temperature Tm 21   p  of the end portion  21   p  and a sufficient increase of the temperature Tm 22   b  of the second conductive region  22   b  are obtained thereby. Thereby, a MEMS element can be provided in which a more stable operation is possible, 
       FIG.  6    is a schematic plan view illustrating a portion of a MEMS element according to the first embodiment. 
       FIG.  6    illustrates the first conductive member  21  of the MEMS element  111  according to the embodiment. Other than the shape of the first conductive member  21 , the configuration of the MEMS element  111  may be similar to that of the MEMS element  110 . 
     As shown in  FIG.  6   , the first conductive member  21  may include a first notch portion  21   n  and a first non-notch portion  21   u . For example, the direction from the first notch portion  21   n  toward the first non-notch portion  21   u  is along the first current path  21   cp  including the first conductive member  21  and the first movable electrode  20 E. 
     A length Wn 1  of the first notch portion  21   n  along a first cross direction Dx 1  perpendicular to the first current path  21   cp  is less than a length Wu 1  of the first non-notch portion  21   u  along the first cross direction Dx 1 . The first conductive member  21  is easily broken at the first notch portion  21   n.    
     For example, it is favorable for the first notch portion  21   n  to be proximate to the first movable electrode  20 E. Thereby, breaking occurs more easily at the first notch portion  21   n  when a portion of the first movable electrode  20 E contacts the first fixed electrode  11 . The distance between the first notch portion  21   n  and the first movable electrode  20 E is short. For example, the distance between the first notch portion  21   n  and the first movable electrode  20 E is not more than ½ of the length of the first conductive member  21  along the first current path  21   cp  including the first conductive member  21  and the first movable electrode  20 E (the sum of the lengths L 21   a  to L 21   g  in  FIG.  2 A ). The distance between the first notch portion  21   n  and the first movable electrode  20 E may be not more than 1/10 of this length. The distance between the first notch portion  21   n  and the first movable electrode  20 E may be not more than 1/20 of this length. The first conductive member  21  breaks more easily. 
     In the MEMS element  111 , the first notch portion  21   n  overlaps the end portion lip of the first fixed electrode  11  in the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E. Breaking occurs more easily at the first notch portion  21   n.    
       FIGS.  7 A and  7 B  are schematic views illustrating a MEMS element according to the first embodiment. 
       FIG.  7 A  is a plan view as viewed along arrow AR 2  of  FIG.  7 B .  FIG.  7 B  is a perspective view. 
     As shown in  FIG.  7 B , the MEMS element  112  according to the embodiment also includes the first member  41  and the element part  51 . In the MEMS element  112 , the element part  51  includes a second fixed electrode  12  in addition to the first fixed electrode  11 , the first movable electrode  20 E, the first conductive member  21 , and the second conductive member  22 . The configurations of the first fixed electrode  11 , the first movable electrode  20 E, the first conductive member  21 , and the second conductive member  22  of the MEMS element  112  may be similar to those of the MEMS element  110  or the MEMS element  111 . An example of the second fixed electrode  12  will now be described. 
     As shown in  FIG.  7 B , the second fixed electrode  12  is fixed to the first member  41 . The first movable electrode  20 E includes a first electrode region  20 Ea and a second electrode region  20 Eb, The distance between the first electrode region  20 Ea and the first conductive member  21  is less than the distance between the second electrode region  20 Eb and the first conductive member  21 . The first electrode region  20 Ea is at the first conductive member  21  side. The second electrode region  20 Eb is at the second conductive member  22  side. 
     The first electrode region  20 Ea faces the first fixed electrode  11 . The second electrode region  20 Eb faces the second fixed electrode  12 . 
     For example, the controller  70  can be electrically connected to the first fixed electrode  11  via the first control terminal Tc 1 . The controller  70  can be electrically connected to the second fixed electrode  12  via a second control terminal Tc 2 . In the example, the controller  70  is electrically connected to the second conductive member  22  via the second terminal T 2 . For example, a second electrical signal Sg 2  can be applied between the second conductive member  22  and the second fixed electrode  12  by the controller  70 . 
       FIG.  7 B  corresponds to the first state ST 1 . The first state ST 1  is before the second electrical signal Sg 2  is applied between the second conductive member  22  and the second fixed electrode  12 . In the first state ST 1 , the first movable electrode  20 E is supported by the first and second conductive members  21  and  22  to be separated from the second fixed electrode  12 . As described above, in the first state ST 1 , the first movable electrode  20 E is supported by the first and second conductive members  21  and  22  to be separated from the first fixed electrode  11 . 
     The second state ST 2  is, for example, after the second electrical signal Sg 2  is applied between the second conductive member  22  and the second fixed electrode  12 . As described below, the first conductive member  21  and the second conductive member  22  are in a broken state in the second state ST 2 . 
     In the example as shown in  FIGS.  7 A and  7 B , the first movable electrode  20 E includes a third electrode region  20 Ec in addition to the first electrode region  20 Ea and the second electrode region  20 Eb. The third electrode region  20 Ec is between the first electrode region  20 Ea and the second electrode region  20 Eb. 
     As shown in  FIG.  7 A , the element part  51  includes the first supporter  21 S, the second supporter  22 S, and a third supporter  23 S. In the example, the element part  51  further includes a fourth supporter  24 S. The first to fourth supporters  21 S to  24 S are fixed to the first member  41 . 
     At least a portion of the first conductive member  21  is supported by the first supporter  21 S to be separated from the first member  41 . At least a portion of the second conductive member  22  is supported by the second supporter  22 S to be separated from the first member  41 . At least a portion of the third electrode region  20 Ec is supported by the third supporter  23 S to be separated from the first member  41 . At least a portion of the third electrode region  20 Ec is supported by the fourth supporter  24 S to be separated from the first member  41 . In the example, the third electrode region  20 Ec is between the third supporter  23 S and the fourth supporter  24 S. 
     For example, the third electrode region  20 Ec may be a portion that includes the X-axis direction center of the first movable electrode  20 E. For example, the third electrode region  20 Ec is the central portion between the first conductive member  21  and the second conductive member  22 . In the MEMS element  112 , at least a portion of the third electrode region  20 Ec is supported to be separated from the first member  41 . Therefore, for example, the distance between the second electrode region  20 Eb and the second fixed electrode  12  increases as the distance between the first electrode region  20 Ea and the first fixed electrode  11  decreases. Both the first conductive member  21  and the second conductive member  22  easily break more stably. 
     In the example, the first movable electrode  20 E includes a first extension region  28   a . The first extension region  28   a  extends along an extension direction. The extension direction crosses the direction (in the example, the X-axis direction) from the first electrode region  20 Ea toward the second electrode region  20 Eb and is along a surface  41   a  of the first member  41 . In the example, the extension direction is the Y-axis direction. 
     A portion (e.g., an end) of the first extension region  28   a  is connected with the third electrode region  20 Ec. Another portion (e.g., another end) of the first extension region  28   a  is connected with the third supporter  23 S. Thus, at least a portion of the third electrode region  20 Ec may be supported by the third supporter  23 S via the first extension region  28   a  to be separated from the first member  41 . 
     In the example, the first movable electrode  20 E includes a second extension region  28   b . The third electrode region  20 Ec is between the first extension region  28   a  and the second extension region  28   b  in the extension direction (e.g., the Y-axis direction) recited above. At least a portion of the third electrode region  20 Ec may be supported by the fourth supporter  24 S via the second extension region  28   b  to be separated from the first member  41 . 
     For example, the third supporter  23 S and the fourth supporter  24 S may be electrically insulated from the first movable electrode  20 E. The first electrode region  20 Ea, the second electrode region  20 Eb, the third electrode region  20 Ec, the first extension region  28   a , and the second extension region  28   b  may be a continuous conductive layer. For example, the first extension region  28   a  and the second extension region  28   b  may function as torsion springs. 
     As described below, in the MEMS element  112 , the first conductive member  21  and the second conductive member  22  can be more stably broken by providing the first fixed electrode  11  and the second fixed electrode  12 . A MEMS element can be provided in which a stable operation is possible. 
       FIGS.  8 A to  9 C  are schematic cross-sectional views illustrating the MEMS element according to the first embodiment. These drawings correspond to a line B 1 -B 2  cross section of  FIG.  7 A . 
     In the first state ST 1  shown in  FIG.  8 A , for example, the second conductive member  22 , the first fixed electrode  11 , and the second fixed electrode  12  are set to the floating state FLT or the ground potential V 0 . In the first state ST 1 , the element part  51  is in the conducting state (the on-state). 
     As shown in  FIG.  8 B , for example, the second terminal  12  (the second conductive member  22 ) is set to the ground potential V 0 ; and the first electrical signal Sg 1  is applied to the first fixed electrode  11 . The first electrode region  20 Ea contacts the first fixed electrode  11 . Because the third electrode region  20 Ec is supported via the first extension region  28   a  to be separated from the first member  41 , the distance between the second electrode region  20 Eb and the second fixed electrode  12  increases. The temperature of the first conductive member  21  at the vicinity of the end portion  20 Ep of the first movable electrode  20 E easily increases locally. The temperature of the end portion  21   p  at the first movable electrode  20 E side of the first conductive member  21  locally increases. 
     When the temperature of the end portion  20 Ep and the end portion  21   p  locally increases, the first conductive member  21  breaks; and the break portion  21 B is formed as shown in  FIG.  8 B . 
     As shown in  FIG.  8 C , the broken first conductive member  21  may approach the state of  FIG.  8 A  due to the restoring force due to the elasticity of the first conductive member  21 . 
     As shown in  FIG.  9 A , for example, the second terminal T 2  (the second conductive member  22 ) is set to the ground potential V 0 ; and the second electrical signal Sg 2  is applied to the second fixed electrode  12 . At this time, for example, the first fixed electrode  11  is set to the ground potential V 0  or a high-impedance state Hi-Z. The temperature of the second conductive member  22  increases, and the second conductive member  22  breaks. The second conductive member  22  is divided at the break portion  22 B. The application of the second electrical signal Sgt ends. 
     As shown in  FIG.  9 B , the broken second conductive member  22  may approach the state of  FIG.  9 A  due to the restoring force due to the elasticity of the second conductive member  22 . 
     In the second state ST 2  shown in  FIG.  9 C , for example, the second conductive member  22 , the first fixed electrode  11 , and the second fixed electrode  12  are in the floating state FLT. In the second state ST 2 , the element part  51  is in the nonconducting state (the off-state). 
     In the MEMS element  112 , both the first conductive member  21  and the second conductive member  22  easily break in the second state ST 2 . The current that flows between the first terminal T 1  and the second terminal T 2  can be stably blocked. 
       FIGS.  10 A and  10 B  are schematic cross-sectional views illustrating the MEMS element according to the embodiment. 
     These drawings illustrate another operation of the MEMS element  112 . These drawings illustrate an operation after the operation described in reference to  FIGS.  8 A to  8 C  is performed. 
     As shown in  FIG.  10 A , for example, the second terminal T 2  (the second conductive member  22 ) is set to the ground potential V 0 ; and a third electrical signal Sg 3  is applied to the first fixed electrode  11 . For example, the absolute value of the third electrical signal Sg 3  is greater than the absolute value of the first electrical signal Sg 1 . The second conductive member  22  is broken thereby. As shown in  FIG.  10 A , the broken second conductive member  22  may approach the state of  FIG.  8 C  due to the restoring force due to the elasticity of the second conductive member  22 . 
     In the second state ST 2  shown in  FIG.  10 B , for example, the second conductive member  22 , the first fixed electrode  11 , and the second fixed electrode  12  are in the floating state FLT. In the second state ST 2 , the element part  51  is in the nonconducting state (the off-state). 
     The configuration in which at least a portion of the third electrode region  20 Ec is supported to be separated from the first member  41  is applicable to a configuration in which the second fixed electrode  12  is not provided. For example, the third electrode region  20 Ec, the first extension region  28   a , the second extension region  28   b , the third supporter  23 S, the fourth supporter  24 S, etc., described in reference to the MEMS element  112  (referring to  FIG.  7 A ) may be provided in the MEMS element  110  illustrated in  FIGS.  1 A and  1 B . 
     In the MEMS element  112 , the third electrode region  20 Ec, the third supporter  23 S, and the fourth supporter  24 S may not be provided, and the second fixed electrode  12  may be provided in addition to the first fixed electrode  11 . In such a case, the operation relating to  FIGS.  8 A to  10 B  can be performed because separate voltages can be applied to the first and second fixed electrodes  11  and  12 . A MEMS element can be provided in which a stable operation is possible. 
     Second Embodiment 
       FIGS.  11 A and  11 B  are schematic views illustrating a MEMS element according to a second embodiment. 
       FIG.  11 A  is a plan view as viewed along arrow AR 3  of  FIG.  11 B ,  FIG.  11 B  is a perspective view. 
     As shown in  FIG.  11 B , the MEMS element  120  according to the embodiment also includes the first member  41  and the element part  51 . In the MEMS element  120 , the element part  51  includes the first fixed electrode  11 , the first movable electrode  20 E, the first conductive member  21 , and the second conductive member  22 . In the example, the element part  51  includes the second fixed electrode  12 . The first movable electrode  20 E is supported by the first and second conductive members  21  and  22  to be separated from the first fixed electrode  11 . 
     In the MEMS element  120  as shown in  FIGS.  11 A and  11 B , the width in the Y-axis direction of the first movable electrode  20 E continuously changes. Otherwise, the configuration of the MEMS element  120  may be similar to the configurations of the MEMS elements  110  to  112 . In the MEMS element  120 , the first conductive member  21  and the second conductive member  22  may have meandering structures. 
     For example, in the MEMS element  120  as shown in  FIG.  11 A , the first movable electrode  20 E may further include the third electrode region  20 Ec between the first electrode region  20 Ea and the second electrode region  20 Eb. In the example, the element part  51  includes the first to fourth supporters  21 S to  24 S. These supporters are fixed to the first member  41 . At least a portion of the first conductive member  21  is supported by the first supporter  21 S to be separated from the first member  41 . At least a portion of the second conductive member  22  is supported by the second supporter  22 S to be separated from the first member  41 . At least a portion of the third electrode region  20 Ec is supported by the third supporter  23 S to be separated from the first member  41 . At least a portion of the third electrode region  20 Ec is supported by the fourth supporter  24 S to be separated from the first member  41 . The third electrode region  20 Ec is between the third supporter  23 S and the fourth supporter  24 S. 
     An example of the first movable electrode  20 E of the MEMS element  120  will now be described. 
     As shown in  FIGS.  11 A and  11 B , the first movable electrode  20 E includes a first connection part  21 C and a second connection part  22 C. The first connection part  21 C is connected with the first conductive member  21 . The second connection part  22 C is connected with the second conductive member  22 . 
     The direction from the first connection part  21 C toward the second connection part  22 C is taken as the first direction (the X-axis direction). A direction that crosses the first direction is taken as the second direction Dp 2 . The second direction Dp 2  is, for example, the Y-axis direction. A width E 20  of the first movable electrode  20 E along the second direction Dp 2  increases in the orientation from the first connection part  21 C toward the second connection part  22 C in at least a portion of the first movable electrode  20 E. For example, the width W 20  continuously increases in the orientation from the first connection part  21 C toward the second connection part  22 C in at least a portion of the first movable electrode  20 E. 
     For example, the at least a portion of the first movable electrode  20 E includes a side portion  20 Es. The side portion  20 Es is oblique to the first direction (the X-axis direction). By providing such a side portion  20 Es, the width E 20  continuously increases in the orientation from the first connection part  21 C toward the second connection part  22 C. 
     For example, the side portion  20 Es described above is provided in at least a portion of the first electrode region  20 Ea. 
     It was found that the temperature of the first connection part  21 C (or the first conductive member  21 ) can be effectively caused to locally increase by such a configuration. The first conductive member  21  and the first connection part  21 C can be stably broken thereby. A MEMS element can be provided in which a stable operation is possible. 
     As shown in  FIG.  11 A , the angle between the side portion  20 Es and the first direction (the X-axis direction) is taken as an angle θ 1 . In the MEMS element  120 , the angle θ 1  is, for example, not less than 5 degrees and not more than 85 degrees. As described below, the angle θ 1  may be not more than 62 degrees. For example, the angle θ 1  may be not less than 39 degrees and not more than 62 degrees. 
       FIGS.  12 A and  12 B  are graphs illustrating characteristics of the MEMS element. 
       FIG.  12 A  illustrates simulation results of the temperature increase when the angle θ 1  is modified. In the simulation, the first conductive member  21  and the second conductive member  22  have meandering structures. In the simulation, the angle θ 1  of the side portion  20 Es is modified. The horizontal axis of  FIG.  12 A  is the angle θ 1 . The vertical axis of  FIG.  12 A  is the temperature Tm.  FIG.  12 A  shows a temperature Tm 21 C of the first connection part  21 C and a temperature Tm 22 C of the second connection part  22 C. 
     As shown in  FIG.  12 A , as the angle θ 1  decreases, the temperature Tm 21 C of the first connection part  21 C increases and the first connection part  21 C (or the first conductive member  21 ) easily breaks. When the angle θ 1  is excessively small, the increase of the temperature Tm 22 C of the second connection part  22 C is insufficient, and the second connection part  22 C (or the second conductive member  22 ) does not easily break. It is favorable for the angle θ 1  to be not less than 39 degrees and not more than 70 degrees. The angle θ 1  may be not less than 39 degrees and not more than 62 degrees. A MEMS element can be provided in which a more stable operation is possible. 
       FIG.  12 B  illustrates simulation results of the current density when the angle θ 1  is modified. The horizontal axis of  FIG.  12 B  is the angle θ 1 . The vertical axis of  FIG.  12 A  is a current density J.  FIG.  12 B  shows a current density J 21 C in the first connection part  21 C and a current density J 22 C in the second connection part  22 C. As shown in  FIG.  12 A , the current density J 21 C in the first connection part  21 C decreases as the angle θ 1  decreases. It is considered that the temperature Tm 21 C of the first connection part  21 C increases as the angle θ 1  decreases because the effect of the thermal resistance increasing as the angle θ 1  decreases is large. 
     In the MEMS element  120  as shown in  FIG.  11 A , in addition to the first fixed electrode  11 , the element part  51  may further include the second fixed electrode  12  that is fixed to the first member  41 . The first movable electrode  20 E includes the first electrode region  20 Ea and the second electrode region  20 Eb. The distance between the first electrode region  20 Ea and the first conductive member  21  is less than the distance between the second electrode region  20 Eb and the first conductive member  21 . The first electrode region  20 Ea faces the first fixed electrode  11 . The second electrode region  20 Eb faces the second fixed electrode  12 . The first movable electrode  20 E is supported by the first and second conductive members  21  and  22  to be separated from the second fixed electrode  12 . 
     In the MEMS element  120 , the first conductive member  21  may include the first notch portion  21   n  and the first non-notch portion  21   u  (referring to  FIG.  6   ). For example, the direction from the first notch portion  21   n  toward the first non-notch portion  21   u  is along the first current path  21   cp  including the first conductive member  21  and the first movable electrode  20 E (referring to  FIG.  6   ). The length Wn 1  of the first notch portion  21   n  along the first cross direction Dx 1  perpendicular to the first current path  21   cp  is less than the length Elul of the first non-notch portion  21   u  along the first cross direction Dx 1  (referring to  FIG.  6   ). The first conductive member  21  easily breaks at the first notch portion  21   n . The first notch portion  21   n  may overlap the end portion lip of the first fixed electrode  11  in the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E (referring to  FIG.  6   ). Breaking occurs more easily at the first notch portion  21   n.    
       FIG.  13    is a schematic cross-sectional view illustrating a MEMS element according to the second embodiment. 
     As shown in  FIG.  13   , in the MEMS element  121  according to the embodiment as well, the width  120  increases in the orientation from the first connection part  21 C toward the second connection part  22 C in at least a portion of the first movable electrode  20 E. For example, the width W 20  continuously increases in the orientation from the first connection part  21 C toward the second connection part  22 C in at least a portion of the first movable electrode  20 E. For example, the at least a portion of the first movable electrode  20 E includes the side portion  20 Es, The side portion  20 Es is oblique to the first direction (the X-axis direction). In the MEMS element  121 , the first conductive member  21  has a meandering structure. The second conductive member  22  includes the first conductive region  22   a  and the second conductive region  22   b . The second conductive region  22   b  is between the first movable electrode  20 E and the first conductive region  22   a . As described in reference to  FIG.  2 B , the second width W 22   b  of the second conductive region  22   b  along the second direction Dp 2  is less than the first width W 22   a  of the first conductive region  22   a  along the second direction Dp 2 . By such a configuration, for example, breaking occurs more easily at the second conductive region  22   b . As described in reference to FIG.  1 A, the second conductive region  22   b  may overlap the end portion  11   q  of the first fixed electrode  11  in the direction (the Z-axis direction) from the first fixed electrode  11  toward the first movable electrode  20 E. Breaking occurs more easily. 
     According to the first and second embodiments, it is favorable for the electrical resistances of the first and second conductive members  21  and  22  to be, for example, not more than 10Ω. Because the electrical resistance is low, a signal that includes high frequencies can be efficiently transmitted with low loss. 
     According to the first and second embodiments, for example, at least one of the first conductive member  21  or the second conductive member  22  includes at least one selected from the group consisting of Al, Cu, Au, Ti, Pd, Pt, and W. A low resistance is obtained, and good transmission in the element part  51  is obtained. 
       FIG.  14    is a schematic cross-sectional view illustrating a MEMS element according to the embodiment. 
       FIG.  14    illustrates the MEMS element  125  according to the embodiment.  FIG.  14    illustrates the first state ST 1 . As shown in  FIG.  14   , the MEMS element  125  further includes a second member  42  in addition to the first member  41  and the element part  51 . The first fixed electrode  11  and the first movable electrode  20 E are between the first member  41  and the second member  42 . In the first state ST 1 , the first gap g 1  is between the first fixed electrode  11  and the first movable electrode  20 E. In the first state ST 1 , a second gap g 2  is between the first movable electrode  20 E and the second member  42 . The element part  51  of the MEMS element  125  may have the configuration described in reference to the first or second embodiment. 
     The second member  42  is, for example, a cap. The first movable electrode  20 E can be displaced along the Z-axis direction due to the first and second gaps g 1  and g 2 . For example, the first gap g 1  and the second gap g 2  may be in a reduced-pressure state. For example, an inert gas may be introduced to the first and second gaps g 1  and g 2 . 
     For example, the first member  41  may include a control circuit part  41   t . The control circuit part  41   t  includes, for example, a switching element such as a transistor, etc. The application of the first electrical signal Sg 1  to the first fixed electrode  11  may be controlled by the control circuit part  41   t.    
     Third Embodiment 
       FIG.  15    is a schematic view illustrating a MEMS element according to a third embodiment. 
     As shown in  FIG.  15   , the MEMS element  130  according to the embodiment includes multiple element parts  51 . For example, the multiple element parts  51  are connected in parallel. Control signals Vpp can be independently applied to the multiple element parts  51 . 
     For example, the first conductive member  21  and the second conductive member  22  that are included in one of the multiple element parts  51  are breakable independently of the first and second conductive members  21  and  22  included in another one of the multiple element parts  51 . 
     Multiple first capacitance elements  31  are provided in the example. One of the multiple first capacitance elements  31  is connected in series to one of the multiple element parts  51 . The MEMS element  130  is a capacitance element array that includes the multiple element parts  51  and the multiple first capacitance elements  31 . Several of the multiple element parts  51  can be set to the off-state. The electrical capacitance of the MEMS element  130  can be modified by setting several of the multiple element parts  51  to the off-state. 
     Fourth Embodiment 
     A fourth embodiment relates to an electrical circuit.  FIG.  15   , which is described above, illustrates the configuration of the electrical circuit  210  according to the embodiment. As shown in  FIG.  15   , the electrical circuit  210  includes a MEMS element (e.g., the MEMS element  130 ) according to the first to third embodiments and an electrical element  55 . The electrical element  55  is electrically connected to the MEMS element  130 . The electrical element  55  includes at least one selected from the group consisting of a resistance, a capacitance element, an inductor element, a diode, and a transistor. The capacitance element that is included in the electrical dement  55  may include a sensor. For example, the electrical element  55  may include a sensor element. For example, the electrical dement  55  may include a capacitive sensor dement. 
     In the electrical circuit  210 , the MEMS dement (e.g., the MEMS element  130 ) may include multiple element parts  51 . The characteristics of the electrical circuit  210  are controllable by breaking the first conductive member  21  and the second conductive member  22  included in at least one of the multiple dement parts  51 . 
     For example, when the MEMS element  130  includes the first capacitance dement  31 , the electrical capacitance of the MEMS element  130  can be controlled by breaking the first conductive member  21  and the second conductive member  22  included in at least one of the multiple dement parts  51 . As a result, the characteristics of the electrical circuit  210  are controllable. 
     For example, the electrical circuit  210  may be used in a voltage-controlled oscillator (VCO). For example, the electrical circuit  210  may be used in an impedance matching circuit of a high frequency circuit such as an antenna, etc. For example, the electrical circuit  210  may be used in a passive RF tag. For example, the characteristics of the electrical circuit  210  can be appropriately adjusted by adjusting an electrical capacitance or an inductor of the electrical circuit  210 . For example, a voltage-controlled oscillator (VCO) that has stable characteristics is obtained. For example, stable characteristics are obtained in the impedance matching circuit of a high frequency circuit such as an antenna, etc. For example, a passive RF tag or the like that has stable characteristics is obtained. 
       FIGS.  16  and  17    are schematic views illustrating control circuits used in the MEMS element according to the embodiment. 
     As shown in  FIG.  16   , a control circuit  310  includes a voltage step-up circuit  321 , a logic circuit  322 , and a switching matrix  323 . A power supply voltage Vcc is supplied to the voltage step-up circuit  321 . The voltage step-up circuit  321  outputs a high voltage Vh to the switching matrix  323 . The switching matrix  323  outputs multiple control signals Vpp according to a signal  322   a  supplied from the logic circuit  322  to the switching matrix  323 . One of the multiple control signals Vpp is supplied to one of the multiple element parts  51 . 
     As shown in  FIG.  17   , a control circuit  311  includes a control power supply  324 , the logic circuit  322 , and the switching matrix  323 . The control power supply  324  is, for example, a control voltage source or a control current source. The control power supply  324  outputs, to the switching matrix  323 , the high voltage Vh and a large current Ih. The switching matrix  323  outputs the multiple control signals Vpp according to the signal  322   a  supplied from the logic circuit  322  to the switching matrix  323 . One of the multiple control signals Vpp is supplied to one of the multiple element parts  51 . The switching matrix  323  may output multiple control currents Ipp. One of the multiple control currents Ipp is supplied to one of the multiple element parts  51 . 
     For example, at least a portion of the control circuits  310  and  311  is included in, for example, the controller  70 . 
     Embodiments may include the following configurations (e.g., technological proposals). 
     Configuration 1 
     A MEMS element, comprising: 
     a first member; and 
     an element part, 
     the element part including
         a first fixed electrode fixed to the first member,   a first movable electrode facing the first fixed electrode,   a first conductive member electrically connected to the first movable electrode, and   a second conductive member electrically connected to the first movable electrode,       

     the first movable electrode being supported by the first and second conductive members to be separated from the first fixed electrode, 
     the first conductive member having a meandering structure, 
     the second conductive member including a first conductive region and a second conductive region, 
     the second conductive region being between the first movable electrode and the first conductive region, 
     a second width of the second conductive region along a second direction being less than a first width of the first conductive region along the second direction, 
     the second direction crossing a first direction from the first movable electrode toward the first conductive region. 
     Configuration 2 
     The MEMS element according to Configuration 1, wherein 
     the second width is not less than 0.1 times the first width. 
     Configuration 3 
     The MEMS element according to Configuration 1 or 2, wherein 
     a length of the second conductive region along the first direction is less than a length of the first conductive region along the first direction. 
     Configuration 4 
     The MEMS element according to any one of Configurations 1 to 3, wherein 
     the second conductive region overlaps an end portion of the first fixed electrode in a direction from the first fixed electrode toward the first movable electrode. 
     Configuration 5 
     The MEMS element according to any one of Configurations 1 to 3, wherein 
     the first conductive member includes a first notch portion and a first non-notch portion, 
     a direction from the first notch portion toward the first non-notch portion is along a first current path including the first conductive member and the first movable electrode, and 
     a length of the first notch portion along a first cross direction perpendicular to the first current path is less than a length of the first non-notch portion along the first cross direction. 
     Configuration 6 
     The MEMS element according to Configuration 5, wherein 
     the first notch portion overlaps an end portion of the first fixed electrode in a direction from the first fixed electrode toward the first movable electrode. 
     Configuration 7 
     The MEMS element according to any one of Configurations 1 to 6, wherein 
     the element part further includes a second fixed electrode fixed to the first member, 
     the first movable electrode includes a first electrode region and a second electrode region, 
     a distance between the first electrode region and the first conductive member is less than a distance between the second electrode region and the first conductive member, 
     the first electrode region faces the first fixed electrode, 
     the second electrode region faces the second fixed electrode, and 
     the first movable electrode is supported by the first and second conductive members to be separated from the second fixed electrode. 
     Configuration 8 
     The MEMS element according to Configuration 7, wherein 
     the first movable electrode further includes a third electrode region between the first electrode region and the second electrode region, 
     the element part includes:
         a first supporter fixed to the first member;   a second supporter fixed to the first member; and   a third supporter fixed to the first member,       

     at least a portion of the first conductive member is supported by the first supporter to be separated from the first member, 
     at least a portion of the second conductive member is supported by the second supporter to be separated from the first member, and 
     at least a portion of the third electrode region is supported by the third supporter to be separated from the first member. 
     Configuration 9 
     The MEMS element according to any one of Configurations 1 to 6, wherein 
     the first movable electrode includes a first electrode region, a second electrode region, and a third electrode region, 
     the first electrode region is between the first conductive member and the second conductive member, 
     the second electrode region is between the first electrode region and the second conductive member, 
     the third electrode region is between the first electrode region and the second electrode region, 
     the element part includes:
         a first supporter fixed to the first member;   a second supporter fixed to the first member; and   a third supporter fixed to the first member,       

     at least a portion of the first conductive member is supported by the first supporter to be separated from the first member, 
     at least a portion of the second conductive member is supported by the second supporter to be separated from the first member, and 
     at least a portion of the third electrode region is supported by the third supporter to be separated from the first member. 
     Configuration 10 
     The MEMS element according to any one of Configurations 1 to 9, wherein 
     the first movable electrode is supported by the first and second conductive members to be separated from the first fixed electrode in a first state before a first electrical signal is applied between the second conductive member and the first fixed electrode, and 
     the first conductive member and the second conductive member are in a broken state in a second state after the first electrical signal is applied between the second conductive member and the first fixed electrode. 
     Configuration 11 
     A MEMS element, comprising: 
     a first member; and 
     an element part, 
     the element part including:
         a first fixed electrode fixed to the first member;   a first movable electrode facing the first fixed electrode;   a first conductive member electrically connected to the first movable electrode; and   a second conductive member electrically connected to the first movable electrode,       

     the first movable electrode being supported by the first and second conductive members to be separated from the first fixed electrode, 
     the first movable electrode including:
         a first connection part connected with the first conductive member; and   a second connection part connected with the second conductive member,       

     a width of the first movable electrode along a second direction increasing in an orientation from the first connection part toward the second connection part in at least a portion of the first movable electrode, 
     the second direction crossing a first direction from the first connection part toward the second connection part. 
     Configuration 12 
     The MEMS element according to Configuration 11, wherein 
     the at least a portion of the first movable electrode includes a side portion oblique to the first direction. 
     Configuration 13 
     The MEMS element according to Configuration 11, wherein 
     the element part further includes a second fixed electrode fixed to the first member, 
     the first movable electrode includes a first electrode region and a second electrode region, 
     a distance between the first electrode region and the first conductive member is less than a distance between the second electrode region and the first conductive member, 
     the first electrode region faces the first fixed electrode, 
     the second electrode region faces the second fixed electrode, 
     the first movable electrode is supported by the first and second conductive members to be separated from the second fixed electrode, 
     at least a portion of the first electrode region includes a side portion oblique to the first direction, and 
     a width of the first electrode region along the second direction increases in the orientation from the first connection part toward the second connection part at the at least a portion of the first electrode region. 
     Configuration 14 
     The MEMS element according to Configuration 13, wherein 
     the first movable electrode further includes a third electrode region between the first electrode region and the second electrode region, 
     the element part includes:
         a first supporter fixed to the first member;   a second supporter fixed to the first member; and   a third supporter fixed to the first member,       

     at least a portion of the first conductive member is supported by the first supporter to be separated from the first member, 
     at least a portion of the second conductive member is supported by the second supporter to be separated from the first member, 
     at least a portion of the third electrode region is supported by the third supporter to be separated from the first member. 
     Configuration 15 
     The MEMS element according to Configuration 11, wherein 
     the first movable electrode includes a first electrode region, a second electrode region, and a third electrode region, 
     the first electrode region is between the first conductive member and the second conductive member, 
     the second electrode region is between the first electrode region and the second conductive member, 
     the third electrode region is between the first electrode region and the second electrode region, 
     the element part includes:
         a first supporter fixed to the first member;   a second supporter fixed to the first member; and   a third supporter fixed to the first member,       

     at least a portion of the first conductive member is supported by the first supporter to be separated from the first member, 
     at least a portion of the second conductive member is supported by the second supporter to be separated from the first member, 
     at least a portion of the third electrode region is supported by the third supporter to be separated from the first member, 
     at least a portion of the first electrode region includes a side portion oblique to the first direction, and 
     a width of the first electrode region along the second direction increases in the orientation from the first connection part toward the second connection part at the at least a portion of the first electrode region. 
     Configuration 16 
     The MEMS element according to any one of Configurations 11 to 15, wherein 
     the first conductive member has a meandering structure, 
     the second conductive member includes a first conductive region and a second conductive region, 
     the second conductive region is between the first movable electrode and the first conductive region, and 
     a second width of the second conductive region along the second direction is less than a first width of the first conductive region along the second direction. 
     Configuration 17 
     The MEMS element according to Configuration 16, wherein 
     the second conductive region overlaps an end portion of the first fixed electrode in a direction from the first fixed electrode toward the first movable electrode. 
     Configuration 18 
     The MEMS element according to Configuration 16 or 17, wherein 
     the first conductive member includes a first notch portion and a first non-notch portion, 
     a direction from the first notch portion toward the first non-notch portion is along a first current path including the first conductive member and the first movable electrode, and 
     a length of the first notch portion along a first cross direction is less than a length of the first non-notch portion along the first cross direction perpendicular to the first current path. 
     Configuration 19 
     The MEMS element according to Configuration 18, wherein 
     the first notch portion overlaps an end portion of the first fixed electrode in a direction from the first fixed electrode toward the first movable electrode. 
     Configuration 20 
     An electrical circuit, comprising: 
     the MEMS element according to any one of Configurations 1 to 19; and 
     an electrical element electrically connected to the MEMS element. 
     According to embodiments, a MEMS element and an electrical circuit can be provided in which a stable operation is possible. 
     Hereinabove, exemplary embodiments of the invention are described with reference to specific examples. However, the embodiments of the invention are not limited to these specific examples. For example, one skilled in the art may similarly practice the invention by appropriately selecting specific configurations of components included in MEMS elements and electrical circuits such as first members, element parts, fixed electrodes, movable electrodes, first conductive members, second conductive members, etc., from known art. Such practice is included in the scope of the invention to the extent that similar effects thereto are obtained. 
     Further, any two or more components of the specific examples may be combined within the extent of technical feasibility and are included in the scope of the invention to the extent that the purport of the invention is included. 
     Moreover, all MEMS elements, and electrical circuits practicable by an appropriate design modification by one skilled in the art based on the MEMS elements, and the electrical circuits described above as embodiments of the invention also are within the scope of the invention to the extent that the purport of the invention is included. 
     Various other variations and modifications can be conceived by those skilled in the art within the spirit of the invention, and it is understood that such variations and modifications are also encompassed within the scope of the invention. 
     Various embodiments are described below with reference to the accompanying drawings. 
     The drawings are schematic and conceptual; and the relationships between the thickness and width of portions, the proportions of sizes among portions, etc., are not necessarily the same as the actual values. The dimensions and proportions may be illustrated differently among drawings, even for identical portions, 
     In the specification and drawings, components similar to those described previously or illustrated in an antecedent drawing are marked with like reference numerals, and a detailed description is omitted as appropriate.