JP5485951B2 - Switch device - Google Patents

Description

  The present invention relates to a switch device including a piezoelectric film.

2. Description of the Related Art Conventionally, there has been known a piezoelectric actuator that includes a piezoelectric film and an electrode that applies a voltage to the piezoelectric film, and that changes in size as the piezoelectric film expands and contracts when a voltage is applied to the piezoelectric film. (For example, see Patent Document 1). There is also known a switch device that switches contact / non-contact between a movable contact provided at a movable end of a piezoelectric actuator and a fixed contact provided opposite to the movable contact.
Japanese Patent Application Laid-Open No. 2001-191300

  However, since the piezoelectric film contracts not only in the longitudinal direction but also in the lateral direction, the piezoelectric actuator also bends in the longitudinal direction and the lateral direction. Therefore, before the movable contact and fixed contact of the piezoelectric actuator come into contact, for example, the corner portion of the piezoelectric actuator may come into contact with the opposing member.

  According to a first aspect of the present invention, there is provided a switch device for electrically connecting a fixed contact and a movable contact, wherein the movable end provided with the movable contact and the fixed end provided at a position separated from the movable end are provided. And a piezoelectric actuator that contacts or separates the movable contact with respect to the fixed contact, and the width of the movable end side of the piezoelectric actuator is smaller than the width of the fixed end side.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

The structural example of the switch apparatus 100 which concerns on 1st Embodiment is shown. The side view of the switch apparatus 100 which concerns on 1st Embodiment is shown. The modification of the piezoelectric actuator 131 of 1st Embodiment is shown. The structural example of the switch apparatus 200 which concerns on 2nd Embodiment is shown. The structural example of the switch apparatus 300 which concerns on 3rd Embodiment is shown. 1 shows a configuration example of a test apparatus 410 using a switch apparatus 100 according to a first embodiment, together with a device under test 400. The structural example of the transmission-line switching apparatus 500 using the switch apparatus 100 of 1st Embodiment is shown. 1 shows a configuration example of a test apparatus that performs a loopback test using the switch device 100 according to the first embodiment.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 shows a configuration example of a switch device 100 according to the present embodiment. FIG. 2 shows a side view of the switch device 100 according to the present embodiment. The switch device 100 includes a substrate 110 having a fixed contact 112, a piezoelectric actuator 130 having a movable end 132 and a fixed end 134, a base portion 152, a lid portion 154, a side surface portion 156, a first power supply portion 180, A second power supply unit 190 and a control unit 192 are provided. The switch device 100 applies a voltage to the piezoelectric film of the piezoelectric actuator 130 to expand and contract, thereby moving the movable end 132 of the piezoelectric actuator 130 and electrically connecting or disconnecting the fixed contact 112 and the movable contact 136.

  The substrate 110 has a first surface on which the fixed contact 112 is provided, and a second surface opposite to the first surface. The substrate 110 may be an insulator such as a glass substrate, and may instead be a semiconductor substrate such as silicon. The substrate 110 includes a fixed contact 112, a first wiring 114, a second wiring 116, a first ground line 118, a second ground line 120, a back surface wiring 122, a via 124, a control wiring 126, and a via. 128.

  The fixed contact 112 is fixed to the substrate 110 and contacts or separates from the movable contact 136 of the piezoelectric actuator 130. The fixed contact 112 includes a first fixed contact 112a and a second fixed contact 112b. The fixed contact 112 may be a flat pad without a protrusion. Fixed contact 112 may include aluminum, tungsten, palladium, rhodium, gold, platinum, ruthenium, indium, iridium, osmium, molybdenum, and / or nickel. Here, the fixed contact 112 may be an alloy of two or more materials including these materials.

  In the present embodiment, the switch device 100 has two fixed contacts 112a and 112b. As a result, the switch device 100 switches electrical conduction or non-conduction between the fixed contact 112 a and the fixed contact 112 b via the movable contact 136.

  Instead of this, the switch device 100 may have one fixed contact 112. In this case, the switch device 100 turns on / off the signal transmission from the movable contact 136 to the fixed contact 112, and transmits the signal input from the outside via the movable contact 136 and the fixed contact 112 in the case of ON. You can do it.

  The first wiring 114 is electrically connected to the first fixed contact 112a and extends from the first fixed contact 112a in the direction opposite to the second fixed contact 112b. The first wiring 114 may be formed integrally with the first fixed contact 112a. The second wiring 116 is electrically connected to the second fixed contact 112b and extends from the second fixed contact 112b in the direction opposite to the first fixed contact 112a. The second wiring 116 may be formed integrally with the second fixed contact 112b. When the fixed contacts 112 a and 112 b contact the movable contact 136, the first wiring 114, the first fixed contact 112 a, the movable contact 136, the second fixed contact 112 b, and the second wiring 116 pass through the switch device 100. An electric signal transmission path is formed.

  The first ground line 118 and the second ground line 120 are provided on the substrate 110 on which the first wiring 114 and the second wiring 116 are formed, and are connected to a reference potential. Here, the reference potential supplies a predetermined voltage. In this embodiment, the reference potential is the ground potential (0 V). The first ground line 118 is located on the piezoelectric actuator 130 side. The first ground line 118 and the second ground line 120 run in parallel with the transmission line on both sides of the electric signal transmission line including the first wiring 114, the movable contact 136, and the second wiring 116, and the transmission line and the coplanar A transmission line is formed. Therefore, the transmission line including the first wiring 114, the movable contact 136, and the second wiring 116 has good high-frequency transmission characteristics.

  Here, the interval between the first ground line 118 and the second ground line 120 is set on the wirings of the first wiring 114 and the second wiring 116 on both sides of the first fixed contact 112a and the second fixed contact 112b. It is smaller than the distance between the first ground line 118 and the second ground line 120 on both sides. That is, in the transmission line from the first wiring 114 to the second wiring 116, the distance between the transmission line and the first ground line 118 and the second ground line 120 is kept substantially constant according to the width of the transmission line. Therefore, the transmission line from the first wiring 114 to the second wiring 116 forms a coplanar transmission line and has good high-frequency transmission characteristics.

  The back surface wiring 122 is provided on the second surface of the substrate 110 and transmits an electrical signal that passes through the switch device 100. The back surface wiring 122 includes a land, a connector, and / or an antenna, and may transmit / receive a signal that is allowed to pass through the switch device 100 from the outside.

  The via 124 penetrates through the first surface and the second surface of the substrate 110 and electrically connects the first wiring 114 and the second wiring 116 and the back surface wiring 122. The via 124 may be formed so as to maintain the hermeticity of the upper surface and the lower surface of the substrate 110 in which the through hole is formed by being filled with a conductive material. A plurality of vias 124 may be provided according to the number of fixed contacts 112 provided on the substrate 110.

  A plurality of control wires 126 are provided on the first surface and the second surface of the substrate 110, and transmit electric signals supplied from the first power supply unit 180 and the second power supply unit 190 to the piezoelectric actuator 130, respectively. The control wiring 126 includes a land, a connector, and / or an antenna, and may transmit and receive a signal supplied to the piezoelectric actuator 130 from the outside.

  The via 128 penetrates the first surface and the second surface of the substrate 110 and electrically connects the control wiring 126 on the first surface and the second surface of the substrate 110. The via 128 may be formed so as to maintain the hermeticity of the upper surface and the lower surface of the substrate 110 that is filled with a conductive material and through-holes are formed. A plurality of vias 128 may be provided on the substrate 110 in accordance with the number of electrical signals supplied to the piezoelectric actuator 130. Note that the control wiring 126 and the via 128 may be formed in the lid portion 154.

  The piezoelectric actuator 130 bends in response to voltage application from the first power supply unit 180 and the second power supply unit 190 and moves the movable end 132. As a result, the piezoelectric actuator 130 causes the movable contact 136 provided at the movable end 132 to contact or separate from the first fixed contact 112a and the second fixed contact 112b. The piezoelectric actuator 130 includes a movable end 132, a fixed end 134, a movable contact 136, a first piezoelectric film 138, a second piezoelectric film 140, a support layer 142, an exposed portion 143, and a first piezoelectric film 138. The electrode layer 144 and the electrode layer 146, and the electrode layer 148 and the electrode layer 150 of the second piezoelectric film 140 are included. The piezoelectric actuator 130 is formed by, for example, a semiconductor manufacturing apparatus using a CVD (Chemical Vapor Deposition) method.

  The movable end 132 is an end portion of the piezoelectric actuator 130 that is not fixed. The fixed end 134 is an end portion to which the piezoelectric actuator 130 is fixed, and is provided at a position away from the movable end 132 with respect to the transmission path including the first wiring 114, the movable contact 136, and the second wiring 116. The width on the movable end 132 side of the piezoelectric actuator 130 is smaller than the width on the fixed end 134 side. Therefore, when the piezoelectric actuator 130 warps in the width direction (W direction in FIG. 1), the corner on the movable end 132 side of the piezoelectric actuator 130 is made difficult to contact the substrate 110. Further, since the deformation amount in the thickness direction (H direction in FIG. 1) of the movable end 132 of the piezoelectric actuator 130 is reduced, the contact operation between the fixed contacts 112a and 112b and the movable contact 136 can be stabilized.

  The movable contact 136 is provided at the movable end 132, and contacts or separates from the fixed contact 112 of the substrate 110 according to the movement of the movable end 132. The movable contact 136 may include the same metal as the fixed contact 112. The movable contact 136 has a shape having a protrusion. Instead of this, the movable contact 136 may be brought into contact with the fixed contact 112 by a plane as a plane having no protrusions.

  The movable contact 136 may have a hemispherical shape so as to prevent the fixed contact 112 from being broken or deteriorated, and may instead have a needle shape with a rounded tip. As an example, when the movable contact 136 is in contact with one fixed contact 112 to form a transmission line, the movable contact 136 has a predetermined shape so as to form a transmission line width or the like according to the frequency of the signal to be transmitted. May be provided.

  The first piezoelectric film 138 is formed on the support layer 142 in the inner layer of the piezoelectric actuator 130 and expands and contracts according to the first drive voltage. The first piezoelectric film 138 expands and contracts in the length direction and width direction (W direction) of the piezoelectric actuator 130 when the first drive voltage is applied, and the distance between the fixed contact 112 and the movable contact 136 changes. The piezoelectric actuator 130 is arranged to bend in the direction.

  The first piezoelectric film 138 is, for example, a lead zirconate titanate (PZT) film. Instead, the first piezoelectric film 138 is made of a wurtzite crystal of lead lanthanum zirconate titanate (PLZT), aluminum nitride (AlN), zinc oxide (ZnO), or a perovskite such as barium titanate (BTO). A film formed of a system ferroelectric or the like may be used.

  The second piezoelectric film 140 faces the first piezoelectric film 138 with the support layer 142 interposed therebetween, is provided symmetrically with the first piezoelectric film 138 around the support layer 142, and expands and contracts according to the second drive voltage. The second piezoelectric film 140 expands and contracts in the length direction (L direction) and the width direction (W direction) of the piezoelectric actuator 130 when a second drive voltage is applied, so that the fixed contact 112 and the movable contact 136 are expanded. The piezoelectric actuator 130 is arranged so as to bend in the direction in which the distance between the piezoelectric actuator 130 changes.

  The second piezoelectric film 140 is formed using the same material as the first piezoelectric film 138. The second piezoelectric film 140 may be formed of substantially the same material as the first piezoelectric film 138 and substantially the same shape as the first piezoelectric film 138. Thereby, the stress that causes the first piezoelectric film 138 to warp and the stress that the second piezoelectric film 140 suppresses warpage can be made substantially the same.

  The width on the movable end 132 side of the region where the first piezoelectric film 138 and the second piezoelectric film 140 are provided in the piezoelectric actuator 130 is smaller than the width on the fixed end 134 side. For this reason, the length by which the first piezoelectric film 138 on the movable end 132 side expands and contracts in the width direction is smaller than that on the fixed end 134 side. Further, the length by which the second piezoelectric film 140 on the movable end 132 side expands and contracts in the width direction is smaller than that on the fixed end 134 side. Therefore, the corner portion on the movable end 132 side of the region where the first piezoelectric film 138 and the second piezoelectric film 140 are provided in the piezoelectric actuator 130 is difficult to contact the substrate 110. In addition, since the piezoelectric actuator 130 does not greatly expand and contract in the width direction in the vicinity of the movable end 132, the corner on the movable end 132 side of the piezoelectric actuator 130 becomes difficult to contact the substrate 110.

  In the piezoelectric actuator 130, the end portion on the movable end 132 side of the region where the first piezoelectric film 138 and the second piezoelectric film 140 are provided is first than the end portion of the first ground line 118 on the second ground line 120 side. It is provided at a position away from the fixed contact 112a and the second fixed contact 112b. For this reason, the coplanar transmission path formed by the first wiring 114, the movable contact 136, and the second wiring 116 is not easily affected by the electrical signal supplied to the piezoelectric actuator 130, and thus has good high-frequency transmission characteristics.

  The support layer 142 is provided between the first piezoelectric film 138 and the second piezoelectric film 140. The support layer 142 has elasticity that is deformed by application of force, and is bent when the first piezoelectric film 138 and / or the second piezoelectric film 140 expands and contracts and applies force. In addition, the support layer 142 has rigidity to prevent the piezoelectric actuator 130 from being bent excessively, and when the application of the electric field to the first piezoelectric film 138 and the second piezoelectric film 140 is stopped, the piezoelectric actuator 130 returns to the initial position.

  The support layer 142 has substantially the same area as the first piezoelectric film 138 or the second piezoelectric film 140 on a surface parallel to the first surface of the substrate 110. Alternatively, the support layer 142 may have a larger area than the first piezoelectric film 138 or the second piezoelectric film 140.

  The support layer 142 is heated to a firing temperature together with the piezoelectric film when the first piezoelectric film 138 or the second piezoelectric film 140 is formed. Therefore, the support layer 142 is not broken even when heated to the firing temperature of the first piezoelectric film 138 and the second piezoelectric film 140, does not deteriorate film characteristics such as the piezoelectric constant of the piezoelectric film, and chemically reacts with surrounding members. It is desirable to form with the material which does not produce easily. In addition, when the support layer 142 is formed of an insulating material, the support layer 142 can be formed in a short time by a manufacturing method such as CVD that is less expensive than the metal film.

The support layer 142 is formed of, for example, a material mainly composed of silicon oxide (SiO ₂ ) or silicon nitride (SiN). Instead, the support layer 142 may use a conductor such as aluminum, gold, or platinum, an insulator such as glass, or a semiconductor such as silicon.

  The exposed portion 143 is a portion of the support layer 142 where the first piezoelectric film 138 and the second piezoelectric film 140 are not provided at the movable end 132 of the piezoelectric actuator 130. The movable contact 136 is provided on the exposed portion 143. Since the movable contact 136 is separated from the electrode layers 144, 146, 148 and 150 by the exposed portion 143, the electric signal flowing through the transmission path formed by the movable contact 136 and the fixed contacts 112 a and 112 b is transmitted to the piezoelectric actuator 130. Less susceptible to flowing electrical signals. Further, by increasing the length of the exposed portion 143 in the L direction, the end portion on the movable end 132 side of the region where the first piezoelectric film 138 and the second piezoelectric film 140 are provided is made to be more than the first ground line 118. The first fixed contact 112a and the second fixed contact 112b can be provided at a position farther from the first fixed contact 112a and the second fixed contact 112b.

  The electrode layer 144 and the electrode layer 146 are provided on the upper and lower surfaces of the first piezoelectric film 138 and apply a first drive voltage to the first piezoelectric film 138 via the control wiring 126. Here, the first drive voltage may be a positive or negative constant voltage. The electrode layer 144 and the electrode layer 146 may have a flat plate shape extending in the length direction L of the piezoelectric actuator 130. The electrode layer 144 may have substantially the same shape and the same material as the electrode layer 146.

  The electrode layer 148 and the electrode layer 150 are provided on the upper and lower surfaces of the second piezoelectric film 140, and apply a second drive voltage to the second piezoelectric film 140 via the control wiring 126. The electrode layer 148 and the electrode layer 150 may have a flat plate shape extending in the length direction L of the piezoelectric actuator 130. The electrode layer 148 may be substantially the same shape and material as the electrode layer 150. The electrode layer 150 may have substantially the same shape and material as the electrode layer 144, and the electrode layer 148 may have approximately the same shape and material as the electrode layer 146.

The electrode layers 144, 146, 148, and 150 may be a low-resistance and easy-to-work metal such as aluminum, gold, platinum, copper, indium, tungsten, molybdenum, ruthenium, iridium, and the like. ₂ ), an oxide electrode such as iridium oxide (IrO ₂ ), a ceramic electrode, or a semiconductor such as silicon may be used.

  When silicon is used as the material for the electrode layers 144, 146, 148, and 150, it is preferable to use silicon doped with impurities at a high concentration. The electrode layers 144, 146, 148, and 150 of the present embodiment are platinum with a thickness in the thickness direction H of 0.2 μm. Here, in the case where a platinum film is formed, the platinum film may be formed after titanium, tantalum, chromium, or the like is formed.

  The pedestal portion 152 is made of a semiconductor material, and fixes the fixed end of the piezoelectric actuator 130 to the lid portion 154. Instead of this, the pedestal portion 152 may fix the piezoelectric actuator 130 to the substrate 110.

  In this case, the thickness of the pedestal portion 152 may be equal to or less than the maximum displacement amount of the piezoelectric actuator 130. Here, the maximum amount of displacement of the piezoelectric actuator 130 means the amount of displacement of the piezoelectric actuator 130 when the maximum drive voltage that can be applied to the first piezoelectric film 138 and / or the second piezoelectric film 140 is applied. The pedestal 152 is formed by etching a semiconductor material of a silicon substrate.

  The lid 154 protects the piezoelectric actuator 130. The lid 154 is formed of the same material as the substrate 110. The side surface portion 156 fixes the lid portion 154 to the upper portion of the piezoelectric actuator 130. The side surface portion 156 is formed by etching the semiconductor material of the silicon substrate. The side surface portion 156 may be formed by the same process as the pedestal portion 152.

  The first power supply unit 180 supplies the first drive voltage to the first piezoelectric film 138, and the second power supply unit 190 supplies the second drive voltage to the second piezoelectric film 140, respectively. The control unit 192 controls ON / OFF of the switch device 100 and supplies electric signals to the first power supply unit 180 and the second power supply unit 190.

  When the switch unit 100 is turned on by bringing the fixed contact 112 and the movable contact 136 into contact with each other, the control unit 192 contracts the second piezoelectric film 140 by applying a second driving voltage to the second piezoelectric film 140. Alternatively, the control unit 192 may apply the first driving voltage to the first piezoelectric film 138 to extend the first piezoelectric film 138 when the switch device 100 is turned on. Instead, when the switch device 100 is turned on, the control unit 192 may contract the second piezoelectric film 140 and simultaneously extend the first piezoelectric film 138.

  In addition, the control unit 192 stops the supply of the second drive voltage to the second piezoelectric film 140 when the switch device 100 is turned off by separating the fixed contact 112 and the movable contact 136, and the first piezoelectric The supply of the first drive voltage to the film 138 is stopped. Instead, when the switch device 100 is turned off, the control unit 192 applies a voltage that is different from the second drive voltage to the second piezoelectric film 140 to bias the return of the piezoelectric actuator 130. May be. Instead, the control unit 192 applies a voltage, which is different from the first drive voltage, to the first piezoelectric film 138 to bias the return of the piezoelectric actuator 130 when the switch device 100 is turned off. May be. Instead, the control unit 192 applies a voltage that is different from the first drive voltage to the first piezoelectric film 138 when the switch device 100 is turned off, and further applies a second voltage to the second piezoelectric film 140. The return of the piezoelectric actuator 130 may be urged by applying a voltage that is different from the driving voltage.

  The control unit 192 may be hardware such as an electronic circuit, and instead may be realized by a control system including a control processor that executes software that operates according to a program or the like.

  As described above, the switch device 100 shown in FIG. 1 and FIG. 2 has the piezoelectric actuator 130 whose width on the movable end 132 side is smaller than the width on the fixed end 134 side. The fixed contact 112 and the movable contact 136 can be more reliably brought into contact with each other. Moreover, since the switch apparatus 100 forms a coplanar transmission line when the fixed contact 112 and the movable contact 136 contact, it has a favorable high frequency transmission characteristic.

  FIG. 3 shows a piezoelectric actuator 131 according to a modification of the first embodiment. The piezoelectric actuator 131 of this modification has a first protective film 170 and a second protective film 172 in addition to the piezoelectric actuator 130 of the first embodiment. In the present modification, the description of the portions that have substantially the same configuration as that of the first embodiment will be omitted.

  The first protective film 170 is made of an insulating material, covers at least a part of the first piezoelectric film 138 from the opposite side of the first piezoelectric film 138 from the support layer 142, and is formed at the end of the first piezoelectric film 138. At least in part, it is in contact with the support layer 142. The first protective film 170 and the support layer 142 may be formed so as to cover each layer so that the first piezoelectric film 138, the electrode layer 144, and the electrode layer 146 are not exposed. As an example, the first protective film 170 and the support layer 142 cover each layer. Here, the first protective film 170 and the support layer 142 may be formed by exposing connection portions where the electrode layer 144 and the electrode layer 146 are respectively connected to the control wiring 126.

  The second protective film 172 is made of an insulating material, covers at least a part of the second piezoelectric film 140 from the side opposite to the support layer 142 in the second piezoelectric film 140, and covers the end of the second piezoelectric film 140. At least in part, it is in contact with the support layer 142. The second protective film 172 and the support layer 142 may be formed so as to cover the second piezoelectric film 140, the electrode layer 148, and the electrode layer 150 so as not to be exposed. As an example, the second protective film 172 and the support layer 142 cover each layer. Here, the second protective film 172 and the support layer 142 may be formed by exposing connection portions where the electrode layer 148 and the electrode layer 150 are respectively connected to the control wiring 126.

The first protective film 170 and the second protective film 172 may be formed of substantially the same insulating material as the support layer 142. For example, the first protective film 170 and the second protective film 172 may be formed of silicon oxide (SiO ₂ ) or silicon nitride (SiN). In this case, the first protective film 170 and the second protective film 172 have elasticity and rigidity similarly to the support layer 142, and are formed by being strongly bonded to the support layer 142 with good adhesion.

  In this way, the first protective film 170, the second protective film 172, and the support layer 142 having substantially the same elasticity and rigidity are the first piezoelectric film 138, the second piezoelectric film 140, the electrode layers 144, 146, 148, Therefore, in the process of manufacturing the piezoelectric actuator 131 or when the piezoelectric actuator 131 is bent, physical destruction such as cracking, chipping, or cracking of each layer can be prevented. Further, since the first protective film 170 and the second protective film 172 have rigidity, the rigidity of the piezoelectric actuator 131 can be increased. Thereby, the piezoelectric actuator 131 can prevent adhesion between the contacts.

  In addition, since the first protective film 170 and the second protective film 172 are formed of substantially the same material as the support layer 142, the first protective film 170 and the second protective film 172 can have substantially the same rigidity and elasticity as the support layer 142. Therefore, when the piezoelectric actuator 131 is displaced, the first protective film 170 and the second protective film 172 can suppress the generation of stress due to the mismatch in rigidity and elasticity inside the piezoelectric actuator 131. In addition, the residual stress and thermal stress that act in the direction in which the piezoelectric actuator 131 deflects due to the lamination of a plurality of films and the residual stress and thermal stress that act in the direction to suppress warpage are canceled out by making them substantially the same. Accordingly, warping of the piezoelectric actuator 131 can be suppressed.

  The first protective film 170, the second protective film 172, and the support layer 142 do not expose the second piezoelectric film 140 and the electrode layers 144, 146, 148, and 150 to the outside. It can also be prevented.

  As described above, since the piezoelectric actuator 131 shown in FIG. 3 has the first protective film 170 and the second protective film 172, physical strength, corrosion resistance, and rigidity are improved as compared with the case where the protective layer is not provided. To do.

  FIG. 4 shows a configuration example of the switch device 200 according to the second embodiment. In the description of the switch device 200, substantially the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. The switch device 200 includes a piezoelectric actuator 230 having a shape different from that of the piezoelectric actuator 130 in the first embodiment.

  The piezoelectric actuator 230 has a shape in which the width (the length in the W direction) gradually decreases as it approaches the movable end 232 side from the fixed end 134 side. Thereby, compared with the movable end 132 in 1st Embodiment, the width | variety of the front-end | tip part of the movable end 232 becomes small. Thereby, when the piezoelectric actuator 230 warps in the width direction, the corner of the tip of the movable end 232 of the piezoelectric actuator 230 becomes more difficult to contact the substrate 110.

  In FIG. 4, the piezoelectric actuator 230 has a shape in which a rectangle and a trapezoid are combined because the width gradually decreases from the middle of approaching the movable end 232 side from the fixed end 134 side. Instead of this, the piezoelectric actuator 230 may have a shape in which the width gradually decreases gradually as it approaches the movable end 232 side from the fixed end 134. For example, the piezoelectric actuator 230 may be substantially trapezoidal or substantially triangular.

  FIG. 5 shows a configuration example of the switch device 300 according to the third embodiment. In the description of the switch device 300, substantially the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. The switch device 300 includes a piezoelectric actuator 330 having a shape different from that of the piezoelectric actuator 130 in the first embodiment.

  In the piezoelectric actuator 330, the width on the movable end side of the region where the piezoelectric film is provided is smaller than the width on the fixed end side, and the width (length in the W direction) of the tip where the movable contact 136 of the movable end 332 is provided. The movable end 332 has a shape larger than the width of the portion other than the tip. Thereby, since the area of the movable contact 136 can be enlarged, the movable contact 136 and the fixed contact 112 can be contacted more reliably.

  FIG. 6 shows a configuration example of a test apparatus 410 using the switch apparatus 100 according to the present embodiment, together with the device under test 400. The test apparatus 410 tests at least one device under test 400 such as an analog circuit, a digital circuit, an analog / digital mixed circuit, a memory, and a system on chip (SOC). The test apparatus 410 inputs a test signal based on a test pattern for testing the device under test 400 to the device under test 400, and the device under test based on an output signal output from the device under test 400 according to the test signal. The quality of 400 is judged.

  The test apparatus 410 includes a test unit 420, a signal input / output unit 430, and a control unit 440. The test unit 420 tests the device under test 400 by exchanging electrical signals with the device under test 400. The test unit 420 includes a test signal generation unit 423 and an expected value comparison unit 426.

  The test signal generator 423 is connected to one or a plurality of devices under test 400 via the signal input / output unit 430 and generates a plurality of test signals to be supplied to the device under test 400. The test signal generator 423 may generate an expected value of the response signal output from the device under test 400 according to the test signal.

  The expected value comparison unit 426 compares the data value included in the response signal of the device under test 400 received from the signal input / output unit 430 with the expected value generated by the test signal generation unit 423. The expected value comparison unit 426 determines pass / fail of the device under test 400 based on the comparison result.

  The signal input / output unit 430 electrically connects the device under test 400 to be tested and the test unit 420, and transmits the test signal generated by the test signal generation unit 423 to the device under test 400. The signal input / output unit 430 receives a response signal output from the device under test 400 in accordance with the test signal. The signal input / output unit 430 transmits the received response signal of the device under test 400 to the expected value comparison unit 426. The signal input / output unit 430 may be a performance board on which a plurality of devices under test 400 are mounted. The signal input / output unit 430 includes the switch device 100.

  The switch device 100 is provided between the test unit 420 and the device under test 400 and electrically connects or disconnects between the test unit 420 and the device under test 400. The test apparatus 410 may perform electrical connection or disconnection by the switch apparatus 100 according to the present embodiment.

  In this example, the example in which the signal input / output unit 430 is connected to one device under test 400 and one switch apparatus 100 is provided for each of the input signal line and the output signal line of one device under test 400 has been described. Instead, the signal input / output unit 430 may be connected to a plurality of devices under test 400, and one switch device 100 may be provided for each of the input signal lines and the output signal lines of the plurality of devices under test 400. Further, when one signal input / output line is connected from the signal input / output unit 430 to one device under test 400, one switch device 100 may be provided in one input / output line.

  The control unit 440 transmits a control signal to the test unit 420 and the signal input / output unit 430 in order to execute the test of the test apparatus 410. The control unit 440 transmits a control signal that causes the test unit 420 to generate a test signal or compare a response signal with an expected value in accordance with a test program. The control unit 440 also instructs connection of the switch device 100 provided in the signal input / output line to be connected and disconnection of the switch device 100 provided in the signal input / output line to be disconnected according to the test program. An instruction or the like is transmitted to the signal input / output unit 430. The control unit 440 may include the first power supply unit 180, the second power supply unit 190, and the control unit 192 in FIG.

  The test apparatus 410 according to the above-described embodiment can perform a test using the switch apparatus 100 that includes the piezoelectric actuator 130 that performs a stable contact operation and has good high-frequency transmission characteristics. In addition, the test apparatus 410 can perform a test by using the switch apparatus 100 which has low power consumption switching control by voltage control and has a long life. Moreover, the test apparatus 410 can perform a test using the switch apparatus 100 in which adhesion between the contacts is reduced.

  FIG. 7 shows a configuration example of the transmission path switching apparatus 500 according to the present embodiment. The transmission path switching device 500 includes a plurality of switch devices 100 respectively connected between an input end and a plurality of output ends. The transmission line switching apparatus 500 of this embodiment includes a plurality of switch devices 100a and 100b that are respectively connected between the input terminal A and the output terminals B and C.

  The transmission path switching device 500 electrically connects the input terminal A and the output terminal B by setting the switch device 100a to the ON state and the switch device 100b to the OFF state, and also connects the input terminal A and the output device. The end C is electrically disconnected. Further, the transmission path switching device 500 electrically disconnects the input end A, the output end B, and the output end C by turning the switch device 100a OFF and the switch device 100b ON. The output terminal B and the output terminal C are electrically connected.

  As described above, the transmission path switching device 500 switches the transmission path between the input end and the plurality of output ends by turning ON / OFF the plurality of switch devices, respectively. The transmission path switching device 500 may be a device in which a plurality of switch devices are sealed and accommodated in one package or the like.

  FIG. 8 shows a configuration example of a test apparatus for performing a loopback test according to the present embodiment, together with a device under test 400. A test apparatus for performing a loopback test according to the present embodiment includes a combination of the test apparatus 410 described with reference to FIG. 6 and the transmission path switching apparatus 500 described with reference to FIG. Therefore, the same reference numerals are given to the substantially same operations as those of the test apparatus 410 and the transmission path switching apparatus 500 according to the present embodiment shown in FIGS.

  When supplying a test signal from the test apparatus 410 to the device under test 400, the test apparatus turns on the switch apparatus 100a of the transmission path switching apparatus 500 and turns off the switch apparatus 100b. Further, when the signal output from the device under test 400 is looped back to the device under test 400, the test apparatus turns off the switch device 100a of the transmission path switching device 500 and turns on the switch device 100b. Put it in a state.

  As a result, the test apparatus causes the test apparatus 410 to input a test signal for testing the device under test 400 to the device under test 400 and loops back the signal from the device under test 400 to perform the test. The transmission path to be input to the device 400 can be switched. The test apparatus for performing the loopback test according to the present embodiment has been described as including the single transmission line switching apparatus 500. Instead, the test apparatus includes two or more transmission line switching apparatuses 500, the test apparatus 410, and the device under test. By switching a plurality of transmission paths with the device 400, the test of the device under test 400 and the loopback test using the test signal may be switched.

  According to the test apparatus that performs the loopback test according to the above-described embodiment, the test apparatus performs the test using the switch device 100 including the piezoelectric actuator 130 that performs stable contact operation and has good high-frequency transmission characteristics, and the loopback. You can switch between tests. In addition, the present test apparatus can switch between two tests by using the switch apparatus 100 which has low power consumption switching control by voltage control and has a long life. In addition, this test apparatus can switch between two tests using the switch device 100 in which adhesion between the contacts is reduced.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

100 switch device, 100a switch device, 100b switch device, 110 substrate, 112 fixed contact, 112a first fixed contact 112b second fixed contact, 114 first wiring, 116 second wiring, 118 first ground line, 120 first 2 ground lines, 122 back wiring, 124 via, 126 control wiring, 128 via, 130 piezoelectric actuator, 131 piezoelectric actuator, 132 movable end, 134 fixed end, 136 movable contact, 138 first piezoelectric film, 140 second piezoelectric film, 142 support layer, 143 exposed portion, 144 electrode layer, 146 electrode layer, 148 electrode layer, 150 electrode layer, 152 pedestal portion, 154 lid portion, 156 side surface portion, 170 first protective film, 172 second protective film, 180 first 1 power supply unit, 190 second power supply unit, 192 control unit, 2 0 switch device, 230 piezoelectric actuator, 232 movable end, 300 switch device, 330 piezoelectric actuator, 332 movable end, 400 device under test, 410 test device, 420 test unit, 423 test signal generation unit, 426 expected value comparison unit, 430 Signal input / output unit, 440 control unit, 500 transmission line switching device

Claims (12)

A switch device for electrically connecting a fixed contact and a movable contact,
A piezoelectric actuator having a movable end provided with the movable contact and a fixed end provided at a position distant from the movable end, and causing the movable contact to contact or separate from the fixed contact;
Equipped with a,
The width of the movable end of the piezoelectric actuator, rather smaller than the width of the fixed end,
The piezoelectric actuator is
A support layer formed of an insulating material;
A first piezoelectric film;
A second piezoelectric film provided symmetrically with the first piezoelectric film with the support layer as a center, facing the first piezoelectric film through the support layer;
The switch device has an exposed portion in which the first piezoelectric film and the second piezoelectric film are not provided at the movable end of the piezoelectric actuator . A first fixed contact;
A second fixed contact;
A first wiring extending from the first fixed contact in a direction opposite to the second fixed contact;
A second wiring extending from the second fixed contact in a direction opposite to the first fixed contact;
With
The piezoelectric actuator has the fixed end provided at a position away from the movable end with respect to a transmission line including the first wiring, the movable contact, and the second wiring, and the movable contact is connected to the first wiring. The switch device according to claim 1, wherein the switch device is brought into contact with or separated from one fixed contact and the second fixed contact. The piezoelectric actuator has a piezoelectric film in an inner layer,
The switch device according to claim 1, wherein a width of the movable end side of a region where the piezoelectric film is provided in the piezoelectric actuator is smaller than a width of the fixed end side.   The switch device according to claim 3, wherein the piezoelectric actuator gradually decreases in width as it approaches the movable end side from the fixed end side. The first wiring and the second wiring are provided on a substrate on which the first wiring and the second wiring are formed, and the first wiring, the movable contact, and the electric signal transmission path that includes the second wiring are arranged in parallel with the transmission path. A ground line and a second ground line;
The piezoelectric actuator has a piezoelectric film in an inner layer,
An end portion on the movable end side of the region where the piezoelectric film is provided in the piezoelectric actuator is closer to the first fixed contact and the second fixed contact than the first ground line located on the piezoelectric actuator side. The switch device according to claim 2, wherein the switch device is provided at a distant position. On both sides of the first fixed contact and the second fixed contact, the distance between the first ground line and the second ground line is the second distance on both sides of the first wiring and the second wiring. The switch device according to claim 5, wherein the switch device is smaller than a distance between one ground line and the second ground line. The piezoelectric actuator is
The support layer is formed of an insulating material, covers at least a part of the first piezoelectric film from the side opposite to the support layer in the first piezoelectric film, and covers the support layer at least at a part of the end of the first piezoelectric film. A first protective film in contact with
The support layer is formed of an insulating material, covers at least part of the second piezoelectric film from the side opposite to the support layer in the second piezoelectric film, and covers at least part of the end of the second piezoelectric film. A second protective film in contact with
The switch device according to any one of claims 1 to 6 , further comprising: The switch device according to claim 1, wherein the first piezoelectric film and the second piezoelectric film are PZT films. The support layer, the switch device according to any one of claims 1 to 8 whose main component is SiO ₂ or SiN. A transmission path switching device comprising a plurality of switch devices according to any one of claims 1 to 9 , each connected between an input end and a plurality of output ends. A test apparatus for performing a loopback test on a device under test,
A test unit for exchanging electrical signals with the device under test to test the device under test;
A switch that is provided between the test unit and the device under test and switches between supplying a signal from the test unit to the device under test or looping back a signal from the device under test to the device under test. Item 10. The transmission line switching device according to Item 10 ,
A test apparatus comprising: A test apparatus for testing a device under test,
A test unit for exchanging electrical signals with the device under test to test the device under test;
The switch device according to any one of claims 1 to 9 , which is provided between the test unit and the device under test and electrically connects or disconnects between the test unit and the device under test.
A test apparatus comprising:

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