Sensor module and force sensor device

Abstract

To provide a sensor module that can improve mass productivity of a force sensor device.SOLUTION: The sensor module comprises: a substrate; a sensor chip which is mounted on one surface of the substrate and detects displacement in a predetermined axial direction; a bonding wire which electrically connects a first electrode formed on one surface of the substrate with a second electrode of the sensor chip; and a protective frame placed on the periphery of one surface of the substrate separately from the bonding wire.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a sensor module and a force sensor device. [Background technology]

[0002] Force sensor devices that detect displacement in a predetermined axial direction have been known for some time. One example is a force sensor device that includes a structure made up of a sensor chip, an external force application plate that is arranged around the sensor chip and to which an external force is applied, a base that supports the sensor chip, an external force buffering mechanism that fixes the external force application plate to the base, and a connecting rod that serves as an external force transmission mechanism, and in which the external force application plate and an acting section are connected by the connecting rod (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-254843 Summary of the Invention [Problem to be solved by the invention]

[0004] In the force sensor device of Patent Document 1, the sensor is mounted directly on a housing, which is a structure consisting of a base, shock absorbers, and an external force application plate. When mounting a sensor on a housing that is much larger than the sensor, the distance from the top surface of the housing to the surface of the sensor is large during the wire bonding process to extract signals from the sensor, which causes interference with semiconductor mounting equipment, making it impossible to use regular semiconductor mounting equipment, and reducing mass productivity.

[0005] The present invention has been made in view of the above points, and has an object to provide a sensor module that can improve the mass productivity of force sensor devices. [Means for solving the problem]

[0006] The sensor module (300) comprises a substrate (310), a sensor chip (100) mounted on one surface of the substrate (310) and configured to detect displacement in a predetermined axial direction, a bonding wire (90) that electrically connects a first electrode (313) formed on one surface of the substrate (310) to a second electrode (110) of the sensor chip (100), and a protective frame (320) provided on the periphery of one surface of the substrate (310) and spaced apart from the bonding wire (90), wherein the sensor chip (100) has an electrode formation surface on which the second electrode (110) is formed, and the upper side of the protective frame (320) is open, and in a plan view, the first electrode (313), the electrode formation surface, the second electrode (110), and the bonding wire (90) are exposed from the protective frame (320). The substrate (310) has a mounting portion (311) on which the sensor chip (100) is mounted and two positioning holes (315) that are provided opposite each other across the center of the mounting portion (311) in a plan view, and the protective frame (320) has two other positioning holes (321) that are provided opposite each other across the center of the protective frame (320) in a plan view, and the two positioning holes (315) of the substrate (310) and the two other positioning holes (321) of the protective frame (320) overlap each other in a plan view. .

[0007] The reference symbols in parentheses are added for ease of understanding, are merely examples, and are not limited to the illustrated embodiment. [Effects of the Invention]

[0008] According to the disclosed technique, it is possible to provide a sensor module that can improve the mass productivity of force sensor devices. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view illustrating a force sensor device according to an embodiment; [Figure 2] 1 is a perspective view illustrating a state in which a cover plate of a force sensor device according to an embodiment is removed; [Figure 3] FIG. 3 is a cross-sectional perspective view taken along the line II in FIG. 2. [Figure 4] FIG. 10 is a perspective view illustrating a state in which a cover plate of the strain generating body is removed. [Figure 5] FIG. 1 is a perspective view illustrating a sensor module according to an embodiment. [Figure 6] FIG. 2 is a plan view illustrating a sensor module according to an embodiment. [Figure 7]FIG. 2 is a bottom view illustrating a sensor module according to an embodiment. [Figure 8] FIG. 2 is a perspective view illustrating a substrate. [Figure 9] FIG. 2 is a perspective view of the sensor chip as viewed from above in the Z-axis direction. [Figure 10] FIG. 2 is a plan view of the sensor chip as viewed from above in the Z-axis direction. [Figure 11] FIG. 2 is a perspective view of the sensor chip as viewed from below in the Z-axis direction. [Figure 12] FIG. 2 is a bottom view of the sensor chip as viewed from below in the Z-axis direction. [Figure 13] FIG. 2 is a diagram illustrating symbols indicating forces and moments acting on each axis. [Figure 14] FIG. 2 is a diagram illustrating an example of the arrangement of piezoresistance elements on a sensor chip. [Figure 15] 15 is a partial enlarged view of one set of detection blocks of the sensor chip shown in FIG. 14. FIG. [Figure 16] FIG. 1 is a diagram (part 1) showing an example of a detection circuit using piezoresistance elements. [Figure 17] FIG. 2 is a diagram (part 2) showing an example of a detection circuit using piezoresistance elements. [Figure 18] FIG. 10 is a diagram illustrating an Fx input. [Figure 19] FIG. 10 is a diagram illustrating an Fy input. [Figure 20] FIG. 10 is a plan view illustrating a state in which an upper substrate of a sensor module according to a modified example of the embodiment is removed. [Figure 21] FIG. 10 is a plan view illustrating an upper substrate of a sensor module according to a modified example of the embodiment. [Figure 22] FIG. 10 is a plan view illustrating a sensor module according to a modified example of the embodiment. [Figure 23] FIG. 23 is a cross-sectional view taken along line II-II of FIG. 22. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following describes the preferred embodiments of the present invention with reference to the accompanying drawings. In the drawings, the same components are designated by the same reference numerals, and redundant explanations may be omitted.

[0011] (Force sensor device 1) FIG. 1 is a perspective view illustrating a force sensor device according to an embodiment. FIG. 2 is a perspective view illustrating a state in which a cover plate of the force sensor device according to an embodiment is removed. FIG. 3 is a cross-sectional perspective view taken along line II of FIG. 2. Referring to FIGS. 1 to 3, the force sensor device 1 has a sensor module 300 and a strain-generating body 200. The force sensor device 1 is a multi-axis force sensor device that is mounted on the arm or fingers of a robot used in machine tools, for example.

[0012] The flexure body 200 has a force receiving plate 210, a strain generating part 220, an input transmission part 230, and a cover plate 240. The strain generating part 220 is laminated on the force receiving plate 210, the input transmission part 230 is laminated on the strain generating part 220, and the cover plate 240 is laminated on the input transmission part 230, thereby forming the substantially cylindrical flexure body 200 as a whole. Note that the function of the flexure body 200 is mainly performed by the strain generating part 220 and the input transmission part 230, and therefore the force receiving plate 210 and the cover plate 240 are provided as needed.

[0013] In this embodiment, for convenience, in the force sensor device 1, the cover plate 240 side is referred to as the upper side or one side, and the force receiving plate 210 side is referred to as the lower side or the other side. Furthermore, the surface of each part facing the cover plate 240 is referred to as one side or the upper side, and the surface facing the force receiving plate 210 is referred to as the other side or the lower side. However, the force sensor device 1 can be used upside down or placed at any angle. Furthermore, a planar view refers to viewing an object from the normal direction (Z-axis direction) of the upper surface of the cover plate 240, and a planar shape refers to the shape of the object viewed from the normal direction (Z-axis direction) of the upper surface of the cover plate 240.

[0014] 2 and 3, a sensor module 300 is attached to the input transmission section 230 of the strain body 200. The sensor module 300 holds the sensor chip 100 and is detachable from the strain body 200.

[0015] The sensor chip 100 has the function of detecting displacement in a predetermined axial direction in up to six axes. The strain body 200 has the function of transmitting an applied force and / or moment to the sensor chip 100. In the following embodiments, as an example, a case where the sensor chip 100 detects six axes will be described, but the present invention is not limited to this, and the sensor chip 100 can also be used to detect three axes, for example.

[0016] Fig. 4 is a perspective view illustrating a state in which the cover plate 240 of the strain-generating body 200 has been removed. As shown in Fig. 4, the input transmission section 230 is provided with a housing section 235 that protrudes from the lower surface of the input transmission section 230 toward the strain-generating section 220. The sensor module 300 is fixed to the housing section 235 on the cover plate 240 side. When the sensor module 300 is attached to the input transmission section 230, the housing section 235 allows it to be attached with high positional accuracy.

[0017] Specifically, the central portion 232 has a first connecting portion 234 that is substantially ring-shaped in a plan view, and a substantially cross-shaped accommodation portion 235 that extends from the lower surface of the first connecting portion 234 toward the strain-flexing portion 220. The accommodation portion 235 is provided inside the first connecting portion 234 and is capable of accommodating the sensor chip 100.

[0018] The accommodating section 235 has one end connected to the first connecting section 234, four vertical support sections 235a extending vertically from the lower surface of the first connecting section 234 toward the strain-generating section 220, four horizontal support sections 235b extending horizontally from the lower end of the vertical support sections 235a, and second connecting sections 235c connecting the other ends of the horizontal support sections 235b together.

[0019] Four second connection portions 235d that protrude toward the cover plate 240 are arranged in the accommodation portion 235. Each of the second connection portions 235d is connected to the lower surface of the force points 151 to 154 of the sensor chip 100 (see FIG. 7, etc., described later).

[0020] The accommodation portion 235 is recessed into the strain-flexing portion 220. Five columnar first connection portions 224 are arranged on the strain-flexing portion 220, protruding toward the input transmission portion 230. Each of the first connection portions 224 is connected to at least a portion of the lower surface of the support portions 101 to 105 of the sensor chip 100 (see FIGS. 9 to 12, etc., described later).

[0021] In the strain-generating body 200, when a force or moment is applied to the force-receiving plate 210, the force or moment is transmitted to the center of the strain-generating part 220 connected to the force-receiving plate 210, and for example, a four-beam structure (not shown) undergoes deformation according to the input. At this time, the outer frame part of the strain-generating part 220 and the input transmission part 230 do not deform.

[0022] That is, in the strain-generating body 200, the force-receiving plate 210, the central portion of the strain-generating part 220, and the beam structure are movable parts that deform when subjected to a force or moment in a predetermined axial direction, and the outer frame part of the strain-generating part 220 is a non-movable part that does not deform when subjected to a force or moment. Also, the input transmission part 230, which is joined to the outer frame part of the strain-generating part 220, which is a non-movable part, is a non-movable part that does not deform when subjected to a force or moment, and the cover plate 240, which is joined to the input transmission part 230, is also a non-movable part that does not deform when subjected to a force or moment.

[0023] When the strain-generating body 200 is used in the force sensor device 1, the support portions 101 to 105 of the sensor chip 100 are connected to a first connection portion 224 provided in the center of the strain-generating portion 220, which is a movable portion. Furthermore, the force points 151 to 154 of the sensor chip 100 are connected to a second connection portion 235d provided in the accommodation portion 235, which is a non-movable portion. Therefore, the force points 151 to 154 of the sensor chip 100 do not move, and the detection beams are deformed through the support portions 101 to 105.

[0024] However, the configuration may also be such that the force points 151 to 154 of the sensor chip 100 are connected to a first connection portion 224 provided in the center of the strain-generating portion 220, which is a movable portion, and the support portions 101 to 105 of the sensor chip 100 are connected to a second connection portion 235d provided in the accommodation portion 235, which is a non-movable portion.

[0025] That is, the sensor chip 100 that can be accommodated in the accommodation portion 235 has support portions 101-105 and force points 151-154 whose relative positions change when subjected to a force or moment. In the strain-generating body 200, the central portion of the strain-generating portion 220, which is the movable portion, has a first connection portion 224 that extends toward the input transmission portion 230 and is connected to one of the support portions 101-105 and the force points 151-154. In addition, the accommodation portion 235 has a second connection portion 235d that is connected to the other of the support portions 101-105 and the force points 151-154.

[0026] The sensor module 300 will be described in detail below.

[0027] (sensor module 300) Fig. 5 is a perspective view illustrating a sensor module 300 according to an embodiment. Fig. 6 is a plan view illustrating a sensor module 300 according to an embodiment. Fig. 7 is a bottom view illustrating a sensor module 300 according to an embodiment. Fig. 8 is a perspective view illustrating a substrate 310.

[0028] The sensor module 300 shown in FIGS. 5 to 7 includes a substrate 310 and a sensor chip 100 mounted on the upper surface (one surface) of the substrate 310 and configured to detect displacement in a predetermined axial direction. A first electrode (bonding pad) 313 is formed on the upper surface (one surface) of the substrate 310, and the first electrode 313 and a second electrode 110 of the sensor chip 100 are electrically connected by a bonding wire 90. The substrate 310 also includes a protective frame 320 provided around the periphery of the upper surface (one surface) of the substrate 310 and spaced apart from the bonding wire 90. The substrate 310 may also include a reinforcing plate 330 on its lower surface (the other surface).

[0029] The sensor chip 100 is mounted with its back surface, which is opposite to the electrode formation surface on which the second electrodes 110 are formed, facing the upper surface of the substrate 310 .

[0030] 8, the substrate 310 has an opening (first opening) 314 that exposes a part of the back surface of the sensor chip 100. Specifically, the opening 314 exposes force points 151 to 154 of the sensor chip 100, which will be described later.

[0031] The shape of the substrate 310 is not particularly limited, but may have, for example, a mounting section 311 on which the sensor chip 100 is mounted and an arm section 312 to which the mounting section 311 extends. The opening 314 may be provided in the mounting section 311. By providing the arm section 312, the arm section 312 can be held when attaching the sensor module 300 to the input transmission section 230, and the sensor module 300 can be easily attached to the input transmission section 230.

[0032] The substrate 310 may be provided with positioning holes 315. The positioning holes 315 are holes that can be engaged with protrusions of the input transmission unit 230 and used for positioning when attaching the sensor module 300 to the input transmission unit 230. In the example of Fig. 8, two positioning holes 315 that are circular in plan view are provided opposite each other with the center of the mounting unit 311 in between.

[0033] The thickness of the substrate 310 is not particularly limited and can be appropriately selected depending on the purpose, but can be, for example, about 30 μm to 500 μm.

[0034] The substrate 310 may be a flexible substrate (FPC) or a rigid substrate. Materials constituting a flexible substrate include, for example, PI (polyimide) resin, epoxy resin, PEEK (polyether ether ketone) resin, PEN (polyethylene naphthalate) resin, PET (polyethylene terephthalate) resin, PPS (polyphenylene sulfide) resin, and polyolefin resin. Materials constituting a rigid substrate include, for example, glass epoxy resin and ceramic.

[0035] The protective frame 320 is a member that protects the sensor chip 100 and the bonding wires 90 from coming into contact with other members. In the example of FIG. 5, the protective frame 320 is provided on the periphery of the upper surface of the mounting portion 311. That is, the arm portions 312 protrude from the protective frame 320. It is preferable that the position of the upper surface of the protective frame 320 is higher than the position of the top of the bonding wires 90. This makes it possible to prevent the bonding wires 90 from coming into contact with other members that are located on the electrode formation surface side of the sensor chip 100.

[0036] The protective frame 320 may be provided with positioning holes 321. The positioning holes 321 are holes that can be engaged with protrusions of the input transmission unit 230 and used for positioning when attaching the sensor module 300 to the input transmission unit 230. In the example of Fig. 5 and Fig. 6, two circular positioning holes 321 in a plan view are provided opposite each other across the center of the protective frame 320.

[0037] The thickness of the protective frame 320 is not particularly limited and can be selected appropriately depending on the purpose, but it is preferably greater than the thickness of the sensor chip 100 and the height of the tops of the bonding wires 90 from the upper surface of the substrate 310. The thickness of the protective frame 320 can be, for example, about 700 μm to 1000 μm.

[0038] The material of the protective frame 320 is not particularly limited as long as it is an insulating material, and examples thereof include PPS (polyphenylene sulfide) resin and glass epoxy resin.

[0039] The reinforcing plate 330 is a member for reinforcing the substrate 310. In particular, when the substrate 310 is a flexible substrate, the substrate 310 is reinforced by the reinforcing plate 330, which is expected to improve the mountability when die bonding or wire bonding the sensor chip, and also makes it easier to attach the sensor module 300 to the input transmission unit 230.

[0040] 7, the reinforcing plate 330 has an opening (second opening) 331 that exposes a part of the back surface of the sensor chip 100. Specifically, the opening 331 exposes the force points 151 to 154 of the sensor chip 100.

[0041] The reinforcing plate 330 may be provided with a positioning hole 332. The positioning hole 332 is a hole that can be engaged with a protrusion of the input transmission unit 230 and used for positioning when attaching the sensor module 300 to the input transmission unit 230. In the example of Fig. 7, two positioning holes 332 that are circular in plan view are provided opposite each other across the center of the reinforcing plate 330. The positioning hole 315 of the substrate 310, the positioning hole 321 of the protective frame 320, and the positioning hole 332 of the reinforcing plate 330 overlap in plan view and form a single, connected positioning hole.

[0042] The thickness of the reinforcing plate 330 is not particularly limited and can be selected appropriately depending on the purpose, but is preferably smaller than the thickness of the sensor chip 100. The thickness of the reinforcing plate 330 can be, for example, about 100 μm to 500 μm.

[0043] The material of the reinforcing plate 330 is not particularly limited as long as it is an insulating material, and examples thereof include PPS (polyphenylene sulfide) resin and glass epoxy resin.

[0044] Next, a method for assembling the sensor module 300 will be described.

[0045] First, an adhesive is applied to the four corners of the periphery of the opening 314 on the upper surface of the substrate 310. For example, an epoxy-based or silicone-based resin can be used as the adhesive. Next, the sensor chip 100 is placed on the substrate 310 so as to cover the opening 314, and die-bonded. The second electrode 110 of the sensor chip 100 and the first electrode 313 of the substrate 310 are connected by bonding wires 90 (wire bonding). Then, the protective frame 320 is fixed to the periphery of the upper surface of the mounting portion 311 with an adhesive. The adhesive can be the same as the adhesive described above. Furthermore, a reinforcing plate 330 may be fixed to the lower surface of the mounting portion 311 with an adhesive.

[0046] Next, the sensor chip 100 will be described in detail. In the following description, "orthogonal" includes cases where two lines or sides are within a range of 90°±10°. However, this does not apply unless there is a special individual explanation. Furthermore, "center" or "central" refers to the approximate center or center of an object, not the exact center or center. In other words, variations on the order of manufacturing error are allowed. The same applies to point symmetry, etc.

[0047] FIG. 9 is a perspective view of the sensor chip 100 as viewed from above in the Z-axis direction. FIG. 10 is a plan view of the sensor chip 100 as viewed from above in the Z-axis direction. FIG. 11 is a perspective view of the sensor chip 100 as viewed from below in the Z-axis direction. FIG. 12 is a bottom view of the sensor chip 100 as viewed from below in the Z-axis direction. In FIG. 12, for convenience, surfaces at the same height are shown with the same matte finish pattern. Here, the direction parallel to one side of the top surface of the sensor chip 100 is defined as the X-axis direction, the direction perpendicular to the side is defined as the Y-axis direction, and the thickness direction of the sensor chip 100 (the normal direction to the top surface of the sensor chip 100) is defined as the Z-axis direction. The X-axis direction, Y-axis direction, and Z-axis direction are perpendicular to one another.

[0048] 9 to 12 is a MEMS (Micro Electro Mechanical Systems) sensor chip capable of detecting up to six axes per chip, and is formed from a semiconductor substrate such as an SOI (Silicon On Insulator) substrate. The planar shape of the sensor chip 100 can be, for example, a rectangle (square or oblong) with sides of approximately 7000 μm.

[0049] The sensor chip 100 includes five pillar-shaped support portions 101 to 105. The planar shape of the support portions 101 to 105 can be, for example, a square with sides of approximately 2000 μm. The support portions 101 to 104 are arranged at the four corners of the rectangular sensor chip 100. The support portion 105 is arranged in the center of the rectangular sensor chip 100. The support portions 101 to 104 are a typical example of a first support portion according to the present invention, and the support portion 105 is a typical example of a second support portion according to the present invention.

[0050] Between support portion 101 and support portion 102, there is provided frame portion 112, both ends of which are fixed to support portion 101 and support portion 102 (connecting adjacent support portions). Between support portion 102 and support portion 103, there is provided frame portion 113, both ends of which are fixed to support portion 102 and support portion 103 (connecting adjacent support portions).

[0051] Between the support parts 103 and 104, there is provided a frame part 114 whose both ends are fixed to the support parts 103 and 104 (connecting adjacent support parts). Between the support parts 104 and 101, there is provided a frame part 111 whose both ends are fixed to the support parts 104 and 101 (connecting adjacent support parts).

[0052] In other words, the four frame portions 111, 112, 113, and 114 are formed in a frame shape, and the corners where the frame portions intersect become the support portions 101, 102, 103, and 104.

[0053] An inner corner of support part 101 and an opposing corner of support part 105 are connected by connecting part 121. An inner corner of support part 102 and an opposing corner of support part 105 are connected by connecting part 122.

[0054] An inner corner of support part 103 and an opposing corner of support part 105 are connected by connecting part 123. An inner corner of support part 104 and an opposing corner of support part 105 are connected by connecting part 124.

[0055] That is, the sensor chip 100 has connecting portions 121 to 124 that connect the support portion 105 to the support portions 101 to 104. The connecting portions 121 to 124 are arranged obliquely with respect to the X-axis direction (Y-axis direction). That is, the connecting portions 121 to 124 are arranged non-parallel to the frame portions 111, 112, 113, and 114.

[0056] The support portions 101 to 105, frame portions 111 to 114, and connecting portions 121 to 124 can be formed from, for example, the active layer, BOX layer, and support layer of an SOI substrate, and each can have a thickness of, for example, about 400 μm to 600 μm.

[0057] The sensor chip 100 has four detection blocks B1 to B4. Each detection block has three T-shaped beam structures in which piezoresistance elements, which are strain detection elements, are arranged. Here, the T-shaped beam structure refers to a structure including a first detection beam and a second detection beam that extends from the center of the first detection beam in a direction perpendicular to the first detection beam and connects to the point of force.

[0058] The detection beam refers to a beam on which a piezoresistance element can be arranged, but does not necessarily have to be arranged. In other words, the detection beam can detect force or moment by arranging a piezoresistance element, but the sensor chip 100 may have a detection beam that does not have a piezoresistance element arranged thereon and is not used to detect force or moment.

[0059] Specifically, detection block B1 has T-shaped beam structures 131T1, 131T2, and 131T3. Detection block B2 has T-shaped beam structures 132T1, 132T2, and 132T3. Detection block B3 has T-shaped beam structures 133T1, 133T2, and 133T3. Detection block B4 has T-shaped beam structures 134T1, 134T2, and 134T3. The beam structures are described in more detail below.

[0060] In the detection block B1, a first detection beam 131a is provided parallel to the side of the support portion 101 on the support portion 104 side of the support portion 101 at a predetermined interval so as to bridge the side of the frame portion 111 closer to the support portion 101 and the side of the connecting portion 121 closer to the support portion 105 in a plan view. In addition, a second detection beam 131b is provided, one end of which is connected to the center portion in the longitudinal direction of the first detection beam 131a, and which extends perpendicular to the longitudinal direction of the first detection beam 131a toward the support portion 104 side. The first detection beam 131a and the second detection beam 131b form a T-shaped beam structure 131T1.

[0061] In plan view, a first detection beam 131c is provided parallel to the side of support portion 104 on the support portion 101 side at a predetermined interval so as to bridge the side of frame portion 111 closer to support portion 104 and the side of connecting portion 124 closer to support portion 105. In addition, a second detection beam 131d is provided, one end of which is connected to the longitudinal center of first detection beam 131c, and which extends perpendicular to the longitudinal direction of first detection beam 131c toward support portion 101. First detection beam 131c and second detection beam 131d form a T-shaped beam structure 131T2.

[0062] In plan view, a first detection beam 131e is provided parallel to the edge of support portion 105 on the frame portion 111 side of support portion 105 at a predetermined interval so as to bridge between the side of connecting portion 121 closer to support portion 105 and the side of connecting portion 124 closer to support portion 105. In addition, a second detection beam 131f is provided, one end of which is connected to the longitudinal center of first detection beam 131e, and which extends perpendicular to the longitudinal direction of first detection beam 131e toward the frame portion 111. The first detection beam 131e and the second detection beam 131f form a T-shaped beam structure 131T3.

[0063] The other ends of the second detection beam 131b, the second detection beam 131d, and the second detection beam 131f are connected to each other to form a connection portion 141, and a force point 151 is provided on the underside of the connection portion 141. The force point 151 has, for example, a rectangular prism shape. The T-shaped beam structures 131T1, 131T2, and 131T3, the connection portion 141, and the force point 151 constitute a detection block B1.

[0064] In the detection block B1, the first detection beam 131a, the first detection beam 131c, and the second detection beam 131f are parallel to each other, and the second detection beams 131b and 131d are parallel to the first detection beam 131e. The thickness of each detection beam in the detection block B1 can be, for example, about 30 μm to 50 μm.

[0065] In the detection block B2, a first detection beam 132a is provided parallel to the side of the support portion 102 facing the support portion 101 at a predetermined interval so as to bridge the side of the frame portion 112 closer to the support portion 102 and the side of the connecting portion 122 closer to the support portion 105 in a plan view. In addition, a second detection beam 132b is provided, one end of which is connected to the center of the first detection beam 132a in the longitudinal direction, and which extends perpendicular to the longitudinal direction of the first detection beam 132a toward the support portion 101 side. The first detection beam 132a and the second detection beam 132b form a T-shaped beam structure 132T1.

[0066] In plan view, a first detection beam 132c is provided parallel to the side of support portion 101 facing support portion 102 at a predetermined distance, so as to bridge the side of frame portion 112 closer to support portion 101 and the side of connecting portion 121 closer to support portion 105. In addition, a second detection beam 132d is provided, one end of which is connected to the longitudinal center of first detection beam 132c, and which extends perpendicular to the longitudinal direction of first detection beam 132c toward support portion 102. First detection beam 132c and second detection beam 132d form a T-shaped beam structure 132T2.

[0067] In plan view, a first detection beam 132e is provided parallel to the edge of support portion 105 on the frame portion 112 side of support portion 105 at a predetermined interval so as to bridge between the side of connecting portion 122 closer to support portion 105 and the side of connecting portion 121 closer to support portion 105. In addition, a second detection beam 132f is provided, one end of which is connected to the longitudinal center of first detection beam 132e, and which extends perpendicular to the longitudinal direction of first detection beam 132e toward the frame portion 112. The first detection beam 132e and the second detection beam 132f form a T-shaped beam structure 132T3.

[0068] The other ends of the second detection beam 132b, the second detection beam 132d, and the second detection beam 132f are connected to each other to form a connection portion 142, and a force point 152 is provided on the underside of the connection portion 142. The force point 152 has, for example, a rectangular prism shape. The T-shaped beam structures 132T1, 132T2, and 132T3, the connection portion 142, and the force point 152 constitute a detection block B2.

[0069] In the detection block B2, the first detection beam 132a, the first detection beam 132c, and the second detection beam 132f are parallel to each other, and the second detection beams 132b and 132d are parallel to the first detection beam 132e. The thickness of each detection beam in the detection block B2 can be, for example, about 30 μm to 50 μm.

[0070] In the detection block B3, a first detection beam 133a is provided parallel to the side of the support portion 103 facing the support portion 102 at a predetermined distance so as to bridge the side of the frame portion 113 closer to the support portion 103 and the side of the connecting portion 123 closer to the support portion 105 in a plan view. In addition, a second detection beam 133b is provided, one end of which is connected to the center of the first detection beam 133a in the longitudinal direction, and which extends perpendicular to the longitudinal direction of the first detection beam 133a toward the support portion 102 side. The first detection beam 133a and the second detection beam 133b form a T-shaped beam structure 133T1.

[0071] In plan view, a first detection beam 133c is provided parallel to the side of support portion 102 facing support portion 103 at a predetermined distance, so as to bridge the side of frame portion 113 closer to support portion 102 and the side of connecting portion 122 closer to support portion 105. In addition, a second detection beam 133d is provided, one end of which is connected to the longitudinal center of first detection beam 133c, and which extends perpendicular to the longitudinal direction of first detection beam 133c toward support portion 103. First detection beam 133c and second detection beam 133d form a T-shaped beam structure 133T2.

[0072] In plan view, a first detection beam 133e is provided parallel to the edge of support portion 105 on the frame portion 113 side at a predetermined interval so as to bridge between the side of connecting portion 123 closer to support portion 105 and the side of connecting portion 122 closer to support portion 105. In addition, a second detection beam 133f is provided, one end of which is connected to the longitudinal center of first detection beam 133e, and which extends perpendicular to the longitudinal direction of first detection beam 133e toward the frame portion 113. The first detection beam 133e and the second detection beam 133f form a T-shaped beam structure 133T3.

[0073] The other ends of the second detection beam 133b, the second detection beam 133d, and the second detection beam 133f are connected to each other to form a connection portion 143, and a force point 153 is provided on the underside of the connection portion 143. The force point 153 has, for example, a rectangular prism shape. The T-shaped beam structures 133T1, 133T2, and 133T3, the connection portion 143, and the force point 153 constitute a detection block B3.

[0074] In the detection block B3, the first detection beam 133a, the first detection beam 133c, and the second detection beam 133f are parallel to each other, and the second detection beams 133b and 133d are parallel to the first detection beam 133e. The thickness of each detection beam in the detection block B3 can be, for example, about 30 μm to 50 μm.

[0075] In the detection block B4, a first detection beam 134a is provided parallel to the side of the support portion 104 facing the support portion 103 at a predetermined distance so as to bridge the side of the frame portion 114 closer to the support portion 104 and the side of the connecting portion 124 closer to the support portion 105 in a plan view. In addition, a second detection beam 134b is provided, one end of which is connected to the center of the first detection beam 134a in the longitudinal direction, and which extends perpendicular to the longitudinal direction of the first detection beam 134a toward the support portion 103. The first detection beam 134a and the second detection beam 134b form a T-shaped beam structure 134T1.

[0076] In plan view, a first detection beam 134c is provided parallel to the side of support portion 103 facing support portion 104 at a predetermined distance, so as to bridge the gap between the side of frame portion 114 closer to support portion 103 and the side of connecting portion 123 closer to support portion 105. In addition, a second detection beam 134d is provided, one end of which is connected to the longitudinal center of first detection beam 134c, and which extends perpendicular to the longitudinal direction of first detection beam 134c toward support portion 104. First detection beam 134c and second detection beam 134d form a T-shaped beam structure 134T2.

[0077] In plan view, a first detection beam 134e is provided parallel to the edge of support portion 105 on the frame portion 114 side of support portion 105 at a predetermined interval so as to bridge between the side of connecting portion 124 closer to support portion 105 and the side of connecting portion 123 closer to support portion 105. In addition, a second detection beam 134f is provided, one end of which is connected to the longitudinal center of first detection beam 134e, and which extends perpendicular to the longitudinal direction of first detection beam 134e toward frame portion 114. The first detection beam 134e and the second detection beam 134f form a T-shaped beam structure 134T3.

[0078] The other ends of the second detection beam 134b, the second detection beam 134d, and the second detection beam 134f are connected to each other to form a connection portion 144, and a force point 154 is provided on the underside of the connection portion 144. The force point 154 has, for example, a rectangular prism shape. The T-shaped beam structures 134T1, 134T2, and 134T3, the connection portion 144, and the force point 154 constitute a detection block B4.

[0079] In the detection block B4, the first detection beam 134a, the first detection beam 134c, and the second detection beam 134f are parallel to each other, and the second detection beams 134b and 134d are parallel to the first detection beam 134e. The thickness of each detection beam in the detection block B4 can be, for example, about 30 μm to 50 μm.

[0080] As described above, the sensor chip 100 has four detection blocks (detection blocks B1 to B4). Each detection block is disposed in an area surrounded by an adjacent support portion among the support portions 101 to 104, a frame portion and a connecting portion connecting the adjacent support portion, and the support portion 105. In a plan view, each detection block can be disposed, for example, point-symmetrically with respect to the center of the sensor chip.

[0081] Each detection block also has three T-shaped beam structures. In each detection block, the three T-shaped beam structures include, in plan view, two T-shaped beam structures in which first detection beams are arranged in parallel with a connection portion therebetween, and one T-shaped beam structure having a first detection beam arranged in parallel with a second detection beam of each of the two T-shaped beam structures. The first detection beam of each T-shaped beam structure is arranged between the connection portion and support portion 105.

[0082] For example, in detection block B1, the three sets of T-shaped beam structures include T-shaped beam structures 131T1 and 131T2 in which first detection beams 131a and 131c are arranged in parallel with each other across a connection portion 141 in a plan view, and T-shaped beam structure 131T3 including first detection beam 131e arranged in parallel with second detection beams 131b and 131d of T-shaped beam structures 131T1 and 131T2. The first detection beam 131e of T-shaped beam structure 131T3 is arranged between the connection portion 141 and support portion 105. Detection blocks B2 to B4 have a similar structure.

[0083] The force points 151-154 are locations where an external force is applied, and can be formed from, for example, the BOX layer and support layer of an SOI substrate. The lower surfaces of the force points 151-154 are approximately flush with the lower surfaces of the support portions 101-105.

[0084] In this way, by applying force or displacement from four force points 151 to 154, different beam deformations can be obtained for each type of force, making it possible to realize a sensor with good six-axis separation. The number of force points is the same as the number of displacement input points of the combined strain-generating body.

[0085] In the sensor chip 100, from the viewpoint of suppressing stress concentration, it is preferable that the portions forming the interior angles are rounded.

[0086] The support sections 101 to 105 of the sensor chip 100 are connected to the non-movable sections of the flexure body 200, and the force points 151 to 154 are connected to the movable sections of the flexure body 200. However, the force sensor device can function even if the relationship between movable and non-movable sections is reversed. That is, the support sections 101 to 105 of the sensor chip 100 may be connected to the movable sections of the flexure body 200, and the force points 151 to 154 may be connected to the non-movable sections of the flexure body 200.

[0087] Fig. 13 is a diagram illustrating the symbols that indicate the forces and moments acting on each axis. As shown in Fig. 13, the force in the X-axis direction is designated Fx, the force in the Y-axis direction is designated Fy, and the force in the Z-axis direction is designated Fz. Also, the moment of rotation about the X-axis is designated Mx, the moment of rotation about the Y-axis is designated My, and the moment of rotation about the Z-axis is designated Mz.

[0088] Fig. 14 is a diagram illustrating an example of the arrangement of piezoresistance elements on the sensor chip 100. Fig. 15 is a partially enlarged view of a set of detection blocks on the sensor chip shown in Fig. 14. As shown in Figs. 14 and 15, piezoresistance elements are arranged at predetermined positions on each of the detection blocks corresponding to four force points 151 to 154. The arrangement of the piezoresistance elements in the other detection blocks shown in Fig. 14 is the same as the arrangement of the piezoresistance elements in one detection block shown in Fig. 15.

[0089] 9 to 12, 14, and 15, in a detection block B1 having a connection portion 141 and a force point 151, the piezoresistive element MzR1' is arranged on the first detection beam 131a on a side closer to the second detection beam 131b in a portion located between the second detection beam 131b and the first detection beam 131e. The piezoresistive element FxR3 is arranged on the first detection beam 131a on a side closer to the first detection beam 131e in a portion located between the second detection beam 131b and the first detection beam 131e. The piezoresistive element MxR1 is arranged on the second detection beam 131b on a side closer to the connection portion 141.

[0090] Furthermore, the piezoresistive element MzR2' is arranged on the first detection beam 131c on a side closer to the second detection beam 131d in a portion located between the second detection beam 131d and the first detection beam 131e. The piezoresistive element FxR1 is arranged on the first detection beam 131c on a side closer to the first detection beam 131e in a portion located between the second detection beam 131d and the first detection beam 131e. The piezoresistive element MxR2 is arranged on the second detection beam 131d on a side closer to the connection portion 141.

[0091] Furthermore, the piezoresistive element FzR1' is disposed on the second detection beam 131f on a side closer to the connecting portion 141. The piezoresistive element FzR2' is disposed on the second detection beam 131f on a side closer to the first detection beam 131e. Note that the piezoresistive elements MzR1', FxR3, MxR1, MzR2', FxR1, and MxR2 are disposed at positions offset from the longitudinal center of each detection beam.

[0092] In the detection block B2 having the connection portion 142 and the force point 152, the piezoresistive element MzR4 is arranged on the first detection beam 132a on a side closer to the second detection beam 132b in a portion located between the second detection beam 132b and the first detection beam 132e. The piezoresistive element FyR3 is arranged on the first detection beam 132a on a side closer to the first detection beam 132e in a portion located between the second detection beam 132b and the first detection beam 132e. The piezoresistive element MyR4 is arranged on the second detection beam 132b on a side closer to the connection portion 142.

[0093] Furthermore, the piezoresistive element MzR3 is arranged on the first detection beam 132c, on a side closer to the second detection beam 132d in a portion located between the second detection beam 132d and the first detection beam 132e. The piezoresistive element FyR1 is arranged on the first detection beam 132c, on a side closer to the first detection beam 132e in a portion located between the second detection beam 132d and the first detection beam 132e. The piezoresistive element MyR3 is arranged on the second detection beam 132d, on a side closer to the connection portion 142.

[0094] Furthermore, the piezoresistive element FzR4 is disposed on the second detection beam 132f on a side closer to the connecting portion 142. The piezoresistive element FzR3 is disposed on the second detection beam 132f on a side closer to the first detection beam 132e. Note that the piezoresistive elements MzR4, FyR3, MyR4, MzR3, FyR1, and MyR3 are disposed at positions offset from the longitudinal center of each detection beam.

[0095] In the detection block B3 having the connection portion 143 and the force point 153, the piezoresistive element MzR4' is arranged on the first detection beam 133a on a side closer to the second detection beam 133b in a portion located between the second detection beam 133b and the first detection beam 133e. The piezoresistive element FxR2 is arranged on the first detection beam 133a on a side closer to the first detection beam 133e in a portion located between the second detection beam 133b and the first detection beam 133e. The piezoresistive element MxR4 is arranged on the second detection beam 133b on a side closer to the connection portion 143.

[0096] Furthermore, the piezoresistive element MzR3' is arranged on the first detection beam 133c on a side closer to the second detection beam 133d in a portion located between the second detection beam 133d and the first detection beam 133e. The piezoresistive element FxR4 is arranged on the first detection beam 133c on a side closer to the first detection beam 133e in a portion located between the second detection beam 133d and the first detection beam 133e. The piezoresistive element MxR3 is arranged on the second detection beam 133d on a side closer to the connection portion 143.

[0097] Furthermore, the piezoresistive element FzR4' is disposed on the second detection beam 133f on a side closer to the connecting portion 143. The piezoresistive element FzR3' is disposed on the second detection beam 133f on a side closer to the first detection beam 133e. Note that the piezoresistive elements MzR4', FxR2, MxR4, MzR3', FxR4, and MxR3 are disposed at positions offset from the longitudinal center of each detection beam.

[0098] In the detection block B4 having the connection portion 144 and the force point 154, the piezoresistive element MzR1 is arranged on the first detection beam 134a on a side closer to the second detection beam 134b in a portion located between the second detection beam 134b and the first detection beam 134e. The piezoresistive element FyR2 is arranged on the first detection beam 134a on a side closer to the first detection beam 134e in a portion located between the second detection beam 134b and the first detection beam 134e. The piezoresistive element MyR1 is arranged on the second detection beam 134b on a side closer to the connection portion 144.

[0099] Furthermore, the piezoresistive element MzR2 is disposed on the first detection beam 134c on a side closer to the second detection beam 134d in a portion located between the second detection beam 134d and the first detection beam 134e. The piezoresistive element FyR4 is disposed on the first detection beam 134c on a side closer to the first detection beam 134e in a portion located between the second detection beam 134d and the first detection beam 134e. The piezoresistive element MyR2 is disposed on the second detection beam 134d on a side closer to the connection portion 144.

[0100] Furthermore, the piezoresistive element FzR1 is disposed on the second detection beam 134f on a side closer to the connecting portion 144. The piezoresistive element FzR2 is disposed on the second detection beam 134f on a side closer to the first detection beam 134e. Note that the piezoresistive elements MzR1, FyR2, MyR1, MzR2, FyR4, and MyR2 are disposed at positions offset from the longitudinal center of each detection beam.

[0101] In this way, multiple piezoresistor elements are arranged separately in each detection block in the sensor chip 100. This makes it possible to detect forces or moments in predetermined axial directions along up to six axes, based on changes in output from multiple piezoresistor elements arranged on predetermined beams in response to inputs applied to force points 151 to 154.

[0102] In addition to the piezoresistance elements used for detecting strain, dummy piezoresistance elements may be arranged in the sensor chip 100. The dummy piezoresistance elements are used to adjust the balance of the stress applied to the detection beam and the resistance of the bridge circuit, and, for example, all the piezoresistance elements including the piezoresistance elements used for detecting strain are arranged point-symmetrically with respect to the center of the support part 105.

[0103] In the sensor chip 100, a first detection beam constituting the T-shaped beam structure is provided with a plurality of piezoresistor elements for detecting displacement in the X-axis direction and the Y-axis direction. A second detection beam constituting the T-shaped beam structure is provided with a plurality of piezoresistor elements for detecting displacement in the Z-axis direction. A first detection beam constituting the T-shaped beam structure is provided with a plurality of piezoresistor elements for detecting moment in the Z-axis direction. A second detection beam constituting the T-shaped beam structure is provided with a plurality of piezoresistor elements for detecting moment in the X-axis direction and the Y-axis direction.

[0104] Here, piezoresistor elements FxR1 to FxR4 detect force Fx, piezoresistor elements FyR1 to FyR4 detect force Fy, piezoresistor elements FzR1 to FzR4 and FzR1' to FzR4' detect force Fz, piezoresistor elements MxR1 to MxR4 detect moment Mx, piezoresistor elements MyR1 to MyR4 detect moment My, and piezoresistor elements MzR1 to MzR4 and MzR1' to MzR4' detect moment Mz.

[0105] In this way, in the sensor chip 100, multiple piezoresistor elements are arranged separately in each detection block. This makes it possible to detect displacement in a predetermined axial direction along up to six axes based on changes in the output of multiple piezoresistor elements arranged on predetermined beams according to the direction (axial direction) of the force or displacement applied (transmitted) to the force points 151 to 154. Furthermore, by varying the thickness and width of each detection beam, it is possible to make adjustments such as uniforming or improving the detection sensitivity.

[0106] It is also possible to reduce the number of piezoresistance elements to form a sensor chip that detects displacement in five or fewer predetermined axial directions.

[0107] In the sensor chip 100, forces and moments can be detected, for example, using a detection circuit described below. FIGS. 16 and 17 show examples of detection circuits using piezoresistor elements. In FIGS. 16 and 17, numbers enclosed in squares indicate external output terminals. For example, No. 1 is a power supply terminal for the Fx, Fy, and Fz axes, No. 2 is a negative output terminal for the Fx axis, No. 3 is a GND terminal for the Fx axis, and No. 4 is a positive output terminal for the Fx axis. No. 19 is a negative output terminal for the Fy axis, No. 20 is a GND terminal for the Fy axis, and No. 21 is a positive output terminal for the Fy axis. No. 22 is a negative output terminal for the Fz axis, No. 23 is a GND terminal for the Fz axis, and No. 24 is a positive output terminal for the Fz axis.

[0108] Additionally, No. 9 is the Mx-axis output negative terminal, No. 10 is the Mx-axis GND terminal, and No. 11 is the Mx-axis output positive terminal. No. 12 is the power supply terminal for the Mx, My, and Mz axes. No. 13 is the My-axis output negative terminal, No. 14 is the My-axis GND terminal, and No. 15 is the My-axis output positive terminal. No. 16 is the Mz-axis output negative terminal, No. 17 is the Mz-axis GND terminal, and No. 18 is the Mz-axis output positive terminal.

[0109] Next, the deformation of the detection beam will be described. FIG. 18 is a diagram illustrating an Fx input. FIG. 19 is a diagram illustrating an Fy input. As shown in FIG. 18, when the input from the flexure body 200 on which the sensor chip 100 is mounted is Fx, all of the four force points 151 to 154 tend to move in the same direction (to the right in the example of FIG. 18). Similarly, as shown in FIG. 19, when the input from the flexure body 200 on which the sensor chip 100 is mounted is Fy, all of the four force points 151 to 154 tend to move in the same direction (upward in the example of FIG. 19). That is, although the sensor chip 100 has four detection blocks, in each detection block, all of the force points move in the same direction in response to displacement in the X-axis direction and displacement in the Y-axis direction.

[0110] The sensor chip 100 has one or more first detection beams that are perpendicular to the input displacement direction among the first detection beams of the T-shaped beam structure, and the first detection beams that are perpendicular to the input displacement direction can accommodate large deformations.

[0111] The beams used to detect the Fx input are first detection beams 131a, 131c, 133a, and 133c, all of which are first detection beams with a T-shaped beam structure located a certain distance away from the point of force. The beams used to detect the Fy input are first detection beams 132a, 132c, 134a, and 134c, all of which are first detection beams with a T-shaped beam structure located a certain distance away from the point of force.

[0112] In response to the Fx and Fy inputs, the first detection beam, which has a T-shaped beam structure and in which a piezoresistance element is arranged, undergoes large deformation, enabling the input force to be detected effectively. Furthermore, since the beams not used for input detection are also designed to be able to deform greatly in response to the displacement of the Fx and Fy inputs, the detection beams will not be destroyed even if a large Fx and / or Fy input is applied.

[0113] In addition, conventional sensor chips have beams that cannot deform significantly in response to the Fx input and / or Fy input, and therefore, when a large Fx input and / or Fy input is received, there is a risk that the detection beams that cannot deform may be destroyed. The sensor chip 100 can alleviate such problems. In other words, the sensor chip 100 can improve the beam's resistance to destruction against displacements in various directions.

[0114] In this way, the sensor chip 100 has one or more first detection beams perpendicular to the input displacement direction, and the first detection beams perpendicular to the input displacement direction can deform significantly. Therefore, the Fx input and Fy input can be detected effectively, and the detection beams will not be damaged even if a large Fx input and / or Fy input is received. As a result, the sensor chip 100 can accommodate a large rating, improving the measurement range and load resistance. For example, the sensor chip 100 can be rated at 500 N, about 10 times the conventional rating.

[0115] In addition, the T-shaped beam structure that connects the force point in three directions in each detection block deforms differently depending on the input, allowing multi-axial forces to be detected with good separation.

[0116] Furthermore, because the beam is T-shaped, there are many paths from the beam to the frame and connecting parts, making it easy to route wiring to the outer periphery of the sensor chip, improving layout flexibility.

[0117] In the sensor chip 100, the first detection beams 131a, 131c, 132a, 132c, 133a, 133c, 134a, and 134c, which are arranged opposite each other across each point of force, are significantly deformed by a moment in the Z-axis direction. Therefore, piezo-resistance elements can be arranged on some or all of these first detection beams.

[0118] Furthermore, with respect to displacement in the Z-axis direction, the second detection beams 131b, 131d, 131f, 132b, 132d, 132f, 133b, 133d, 133f, 134b, 134d, and 134f directly connected to each point of force are largely deformed. Therefore, piezoresistive elements can be disposed on some or all of these second detection beams.

[0119] As described above, the sensor module 300 allows the substrate 310 and the sensor chip 100 to be wire-bonded in advance, so that even if the size of the flexure body 200 is very large compared to the sensor chip 100, the sensor chip 100 can be attached to the flexure body 200 as the sensor module 300 using a general semiconductor mounting device. Therefore, the sensor module 300 can improve the mass productivity of the force sensor device 1.

[0120] Furthermore, since the sensor module 300 allows the substrate 310 and the sensor chip 100 to be wire-bonded in advance, the difficulty of wire-bonding can be reduced compared to when the sensor chip 100 is directly attached to the strain-generating body 200, and the quality of the wire-bonding can be improved.

[0121] Furthermore, since the substrate 310 has the opening 314, the force points 151 to 154 of the sensor chip 100 can be exposed, and the force points 151 to 154 can be directly connected to the second connection portion 235d of the input transmission section 230. Therefore, the substrate 310 does not interfere with the connection between the sensor chip 100 and the flexure body 200, and the force sensor device 1 can exhibit force sense characteristics equivalent to those in the case where the sensor chip 100 is directly attached to the flexure body 200.

[0122] The reinforcing plate 330 also has openings 331, similar to the substrate 310, which allows the force points 151 to 154 of the sensor chip 100 to be exposed, and the force points 151 to 154 can be directly connected to the second connection portion 235d of the input transmission section 230. Therefore, the reinforcing plate 330 does not interfere with the connection between the sensor chip 100 and the strain-generating body 200, and the force sensor device 1 can exhibit force-sense characteristics equivalent to those in the case where the sensor chip 100 is directly attached to the strain-generating body 200.

[0123] Furthermore, the inspection can be easily performed because it can be performed in the form of the sensor module 300. Even if the inspection determines that the sensor module 300 is defective, it can be discarded as a sensor module 300 before being assembled into the relatively expensive strain element 200, thereby reducing the final disposal cost.

[0124] (Modification of the sensor module 300) Fig. 20 is a plan view illustrating a state in which an upper substrate 412 of a sensor module 400 according to a modified example of the embodiment is removed. Fig. 21 is a plan view illustrating the upper substrate 412 of a sensor module 400 according to a modified example of the embodiment. Fig. 22 is a plan view illustrating a sensor module 400 according to a modified example of the embodiment. Fig. 23 is a cross-sectional view taken along line II-II of Fig. 22.

[0125] 20 to 23 differs from the sensor module 300 shown in FIGS. 5 to 8 in that it does not have a protective frame and in that the substrate structure is different. As shown in FIG. 20, the sensor module 400 includes a mounting substrate 411 having a cavity 415, a sensor chip 100 mounted in the cavity 415 of the mounting substrate 411 and configured to detect displacement in a predetermined axial direction, and an upper substrate 412 covering the mounting substrate 411 and the sensor chip 100. The sensor chip 100 is mounted with its back surface, located opposite to the electrode formation surface on which the second electrode 110 is formed, facing the bottom surface of the cavity 415. The mounting substrate 411 preferably includes an opening 416 that exposes the force points 151 to 154 of the sensor chip 100, as shown in FIG.

[0126] The upper substrate 412 has an opening 413 that exposes the second electrode 110 of the sensor chip 100, as shown in Fig. 21. A first electrode (bonding pad) 414 is formed on the upper surface (one surface) of the upper substrate 412, as shown in Fig. 22, and the first electrode 414 and the second electrode 110 of the sensor chip 100 are electrically connected by a bonding wire 90. The first electrode 414 is preferably provided on the periphery of the opening 413, from the viewpoint of shortening the distance between the first electrode 414 and the second electrode 110 in wire bonding. A wiring member, such as a flexible flat cable (FFC), may be connected to the upper surface of the upper substrate 412.

[0127] The thickness of the mounting substrate 411 and the upper substrate 412 and the materials forming the mounting substrate 411 and the upper substrate 412 can be the same as those of the substrate 310 of the sensor module 300 .

[0128] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0129] For example, in the above-described embodiment, an example has been described in which the strain-generating body is fastened to the object to be measured with a screw, but this is not limited to this, and various fasteners such as bolts and rivets can be used as long as they can fix the strain-generating body to the object to be measured. [Explanation of symbols]

[0130] 1 Force sensor device, 90 Bonding wire, 100 Sensor chip, 101 to 105 Support portion, 110 Second electrode, 111 to 114 Frame portion, 121 to 124 Connecting portion, 131a, 131c, 131e, 131g, 132a, 132c, 132e, 133a, 133c, 133e, 134a, 134c, 134e First detection beam, 131b, 131d, 131f, 131h, 132b, 132d, 132f, 133b, 133d, 133f, 134b, 134d, 134f Second detection beam, 131T1, 131T2, 131T3, 131T4, 132T1, 132T2, 132T3, 133T1, 133T2, 133T3, 134T1, 134T2, 134T3 T-shaped beam structure, 141 to 144 connection portion, 151 to 154 force point, 200 strain generating body, 210 force receiving plate, 238 screw hole, 220 strain generating portion, 224 first connection portion, 230 input transmission portion, 232 center portion, 234 first connection portion, 235 storage portion, 235a vertical support portion, 235b horizontal support portion, 235c second connection portion, 235d second connection portion, 238 screw hole, 240 cover plate, 300, 400 sensor module, 310 Substrate, 311 mounting portion, 312 arm portion, 313, 414 first electrode, 314 first opening, 320 protective frame, 315, 321, 332 positioning hole, 330 reinforcing plate, 331 second opening, 411 mounting substrate, 412 upper substrate, 413, 416 opening, 415 cavity

Claims

1. A substrate; a sensor chip mounted on one surface of the substrate and configured to detect displacement in a predetermined axial direction; a bonding wire that electrically connects a first electrode formed on one surface of the substrate to a second electrode of the sensor chip; a protective frame provided at a periphery of one surface of the substrate and spaced apart from the bonding wires; the sensor chip has an electrode formation surface on which the second electrode is formed, The upper side of the protective frame is open, In a plan view, the first electrode, the electrode forming surface, the second electrode, and the bonding wire are exposed from the protective frame; the substrate has a mounting portion on which the sensor chip is mounted, and two positioning holes provided opposite to each other across the center of the mounting portion in a plan view, the protective frame has two separate positioning holes that are provided opposite to each other across the center of the protective frame in a plan view, the two positioning holes of the substrate and the two other positioning holes of the protective frame overlap each other in a plan view; Sensor module.

2. The sensor module according to claim 1 , wherein a position of an upper surface of the protective frame is higher than a position of a top of the bonding wire.

3. the sensor chip has a back surface located opposite to the electrode formation surface, and is mounted on the substrate with the back surface facing one surface side; The sensor module according to claim 1 , wherein the substrate has a first opening that exposes a part of the back surface of the sensor chip.

4. the sensor chip has a force point to which an external force is applied; The sensor module according to claim 3 , wherein the force point is exposed from the first opening.

5. a reinforcing plate is provided on the other surface of the substrate; The sensor module according to claim 4 , wherein the reinforcing plate has a second opening that exposes the force point.

6. The sensor module according to claim 1 , wherein the substrate has an arm portion from which the mounting portion extends.

7. a strain-generating body having a strain-generating part including a movable part that deforms when subjected to a force or moment in a predetermined axial direction and a non-movable part that does not deform when subjected to the force or moment, and an input transmission part that is joined to the non-movable part and does not deform when subjected to the force or moment; A force sensor device comprising: the sensor module according to claim 1 , fixed to the input transmission section.

8. the input transmission unit has a connection unit, The force sensor device according to claim 7 , wherein the connection portion is connected to a force point of the sensor chip.

9. The force sensor device according to claim 7 , wherein the input transmission section has a housing section capable of housing the sensor module.

Images