JP2008059895A - Contact sheet and its manufacturing method, and cable and elastic member for forming contact sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact sheet achieving a long lifetime as a sheet while responding to a narrow pitch, and to provide its manufacturing method, as well as an intermediate body for forming such a contact sheet. <P>SOLUTION: The contact sheet is provided with an elastic member capable of demonstrating conductivity and a substrate having a plurality of support portions capable of engaging with the elastic members individually. The support portions have a structure to be engaged with and support the elastic members detachably. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a conductive contact sheet that is also used as an electronic component inspection jig for measuring and inspecting electrical characteristics of an electronic component such as an integrated circuit (IC), a manufacturing method thereof, and a contact sheet thereof And an elastic member having conductivity.

  When measuring the electrical characteristics of an electronic component such as an integrated circuit (IC), the inspection circuit arranged on the inspection substrate and the terminals or bumps of the electronic component to be inspected are electrically connected by a contact sheet. . The contact sheet is a sheet having anisotropic conductivity and elasticity in the thickness direction, and typical examples thereof include a metal particle type shown in FIG. 13 and a metal wire buried type shown in FIG.

  In the metal particle type, the contact sheet 131 has a structure in which the metal particles 133 are dispersed in the elastic member 132. In an unloaded state, the metal particles 53 are moderately dispersed, and the upper and lower surfaces of the contact sheet 131 are electrically insulated. In this state, when the contact sheet 131 is pressed by the test object, for example, the solder bump 135 of the IC 134, the elastic member 132 is compressed and deformed. As a result, the metal particles 133 are in contact with each other, and only the pressed portion is between the upper and lower surfaces. Conductivity develops.

  In the metal wire embedded type, the contact sheet 141 is embedded in the elastic member 142 so that the metal thin wires 143 do not contact each other obliquely. For this reason, the upper and lower surfaces of the contact sheet 141 are electrically connected independently by the thin metal wires 143. When the elastic member 142 is deformed by the pressing contact of the object to be inspected, the fine metal wires 143 are deformed so as to fall down obliquely, but do not contact each other. For this reason, the function of electrically conducting the upper and lower surfaces independently can be maintained, and anisotropic conductivity is realized.

  This contact sheet is elastic in the thickness direction, has anisotropic conductivity in the thickness direction under a load caused by a low compressive load, and further has an elastic recovery force for frequent use. It is required to be suitable. In addition, with high-density mounting and the like, it is required to refine the pattern such as the size and pitch of each conductive portion of a contact sheet used for inspection.

As an example of an invention that meets these requirements, a contact sheet has been proposed in which through holes are provided in a plurality of locations of a base film made of an electrically insulating porous film, and a conductive metal made of plated particles is attached to the inner wall thereof ( For example, see Patent Document 1.)
JP 2004-265844 A

  However, in such a structure, when pressed by an inspection object such as a bump, the elastic material around the contact portion is also elastically deformed in a wide range. For this reason, when the pitch is narrowed and the distance between the pressing points is narrowed, the elastic modulus of the contact portion of the contact sheet is apparently increased, and there is a problem that the contact becomes unstable.

  If the elastic modulus of the sheet as a whole is reduced as a countermeasure, the amount of deformation increases, and the metal wire buckling or the conductive path member (corresponding to the plated particle layer in Patent Document 1) is likely to occur. A new problem occurred. If a part of the sheet loses its conductivity due to such a phenomenon, the entire sheet becomes unusable, which causes an increase in cost including the trouble of replacement.

  The object of the present invention is to overcome these problems and provide a contact sheet that can cope with a narrow pitch and achieve a long life as a sheet, a method for manufacturing the contact sheet, and an intermediate for forming the contact sheet. It is in.

(Claim 1)
A contact sheet according to the present invention provided to achieve the above object includes an elastic member capable of expressing electrical conductivity, and a substrate including a plurality of holding portions capable of individually engaging the elastic member. The elastic member is detachably engaged and held.

  The “elastic member capable of exhibiting electrical conductivity” refers to a member having elasticity and exhibiting predetermined electrical conductivity constantly or triggered by some external action. As an example of the external action, there is a case where a contact pressure due to a contact object such as a bump acts on the elastic member.

  “The elastic members can be individually engaged” means that one elastic member can be independently positioned with respect to the substrate without being associated with another elastic member. The elastic member is deformed by contact with the contact target, and the substrate itself may have elasticity. Therefore, the term “engagement” means that the elastic member is not completely fixed to the substrate, but is allowed to be slightly deformed or moved, and the situation where it comes into contact with the adjacent elastic member is suppressed. Means the state.

  “Removable” means that the elastic member can be engaged and held with respect to the substrate as described above. It means that it can be released. Specifically, for example, when only the elastic member is pressed with a predetermined force, it may come off the substrate. At this time, the holding portion of the substrate after the elastic member is detached is required to be able to engage and hold a new elastic member. One of the detached elastic members may change in conductivity and elasticity by an external action for detachment or may be reusable without changing.

  In the contact sheet according to the first aspect, the elastic member is mainly responsible for contact with the contact object, and the substrate is mainly responsible for defining the relative arrangement of the elastic members corresponding to the contact object. For this reason, the elastic member is not limited to the characteristics required for the entire contact sheet, for example, mechanical characteristics such as rigidity and strength, and has material characteristics and structure specialized for stable electrical connection with the contact object. Good. On the other hand, the substrate has material characteristics and structure specialized in realizing the holding function of the elastic member while achieving the basic characteristics of the entire contact sheet without considering the electrical connection with the contact object. Just do it. By dividing the role in this way, each member can optimize the function assigned to it, and it is possible to obtain a contact sheet having stable electrical connection even when the pitch is narrowed.

In addition, since the holding part provided on the substrate is made to be able to detach the elastic member, when one of the elastic members that are engaged and held cannot achieve a stable electrical connection, The elastic member may be detached and a new elastic member may be engaged. Therefore, it is not necessary to replace the entire contact sheet due to a partial failure of the contact sheet, and the life of the entire contact sheet is prolonged.
As described above, it is possible to provide a contact sheet that achieves both a narrow pitch and a long life by using the above-described configuration.

(Claim 2)
In addition to the structure according to claim 1, the holding portion is a plurality of through holes provided in the substrate, and the elastic member is engaged with the substrate by being at least partially inserted into the through hole. You may have a structure.
In the case of having such a configuration, since the holding portion has a through-hole structure that is easy to process, it can be easily manufactured. Further, the elastic member is embedded and held in engagement with the substrate by at least a part of the elastic member being inserted into the through hole. This process is also simple, and the contact sheet having such a configuration has high productivity.

(Claim 3)
In addition to the structure which concerns on Claim 2, the volume elastic modulus of a holding | maintenance part may have a structure lower than the volume elastic modulus of an elastic member.
Here, the bulk modulus is a constant peculiar to a substance, and when a uniform pressure p is applied to an isotropic elastic body, the volume decreases at a rate of p / k within the proportional limit.
In the case of having such a configuration, when the elastic member is deformed by contact with the inspection object, the volume elastic modulus is smaller than that of the elastic member, so that the deformation of the elastic member is easily absorbed. For this reason, the influence of deformation hardly affects adjacent elastic members, and even when the pitch is narrowed, a situation in which the elastic modulus of the elastic members apparently increases is unlikely to occur. Therefore, the contact sheet having such a configuration is particularly advantageous for narrowing the pitch.

(Claim 4)
Alternatively, in addition to the configuration according to claim 2, the through hole may have a protruding locking point in the hole, and the elastic member may be held in the through hole by the locking point. .

In the case of having such a configuration, the elastic member engaged and held in the through hole is preferentially compressed at the contact portion with the locking point, and is not compressed at the other portion or with the locking point. It is held slightly compressed from the contact portion. For this reason, compared with the case where it hold | maintains on the whole inner surface of a through-hole, the volume which can deform | transform when it contacts a contact object tends to become large. This increase in the deformable volume widens the allowable range for the contact state with the contact object, and contributes to the stabilization of the electrical connection. In such a configuration, it is also possible to provide a gap between the elastic member and the substrate except for the locking point. By reducing the interaction between the substrate and the elastic member in this way, it is possible to sufficiently secure a deformable volume even when the volume elastic modulus of the substrate is increased. In such a case, it is also possible to create a substrate using, for example, a resin plate or a ceramic plate. If the substrate is made a hard member in this way, the processing accuracy is improved and it becomes easy to cope with a narrow pitch. Furthermore, the substrate can be a conductive member such as metal. When the anisotropic conductivity of the elastic member is sufficiently realized, it is possible to cut off the influence of signal crosstalk, which is a concern as the pitch becomes narrower, by using a conductive substrate.
The “projection-like locking point” is a portion that protrudes radially inward to narrow the inner diameter of the through hole, and protrudes continuously in the direction of the central axis of the through hole like a key groove or rib, It may project continuously in the circumferential direction of the through hole in a ring shape, or may project at a part of the inner surface of the through hole, specifically, at the inside or at the opening edge. Further, the protruding locking point may be provided at one place on the inner surface of the through hole or at a plurality of places.

(Claim 5)
In addition to the configuration according to claim 1, the substrate is formed by laminating a plurality of plate materials having a volume modulus of elasticity higher than that of the elastic member, the plate material having a through hole, and the elastic member has at least one through hole. You may have the structure engaged with respect to a board | substrate as a holding | maintenance part.

  In the case of having such a configuration, the through-hole provided in the plate material serves as a ring-shaped locking point, so that it is possible to easily obtain a substrate having a locking point structure. For this reason, the contact sheet having such a configuration realizes a narrow pitch and a long life, and further has high productivity.

In addition, “a plurality of plate members are stacked while being separated” is a state in which a plurality of plate members are stacked so as to have at least a part that does not contact. Here, another member may be arranged as a spacer at least at a part between the substrates to be laminated, or this spacer may constitute a holding portion. Further, the space between the stacked substrates may be filled with another member. At this time, if a member having a low volume elastic modulus is adopted as this member, this member preferentially absorbs deformation of the elastic member due to contact with the contact target.
Further, “with at least one through hole as a holding portion” means that a through hole provided in at least one plate member among a plurality of plate members may function as a holding portion. For example, it is composed of two plate materials, and only the through hole of the plate material on the side opposite to the contact object functions as a holding member, and the through hole provided in the plate material on the side facing the contact object contacts the elastic member. It may be a configuration in which this is inherently included. In the case of this configuration, the elastic member in the portion that comes into contact with the contact target can exhibit the original compression characteristics of the member. When the elastic member is deformed / moved in the direction perpendicular to the thickness direction of the substrate, that is, the in-plane direction of the contact sheet, due to the contact between the contact object and the contact sheet, the contact object is opposed to the contact object. The through-hole on the side plays a role of suppressing the contact with the adjacent elastic member by defining the upper limit of deformation / movement of the elastic member.

(Claim 6)
In addition to the configuration according to claim 1, the holding portion has a plurality of protrusions provided on the substrate, and the elastic member is engaged with the substrate by inserting the protrusion into the elastic member. You may do it.

  In the case of having such a configuration, since the plurality of protrusions provided on the substrate regulate the fluctuation of the elastic member, it is possible to easily obtain the substrate having the holding portion. For this reason, the contact sheet having such a configuration realizes a narrow pitch and a long life, and further has high productivity.

Note that the number of protrusions required to hold one elastic member may be one or more. Further, the protrusions may individually have electrically independent conductivity, or the protrusions do not have conductivity, and a conductive region is formed on the surface having the protrusions of the substrate. The electrical connection to the substrate side may be realized by contacting the conductive region and the conductive member.
A typical example of such a configuration includes a configuration in which the elastic member has a donut shape and is held by inserting a projection substantially the same as the hole diameter into the through hole. At this time, it is desirable that the thickness of the donut-like elastic member is set higher than the protrusion. In this case, the portion of the elastic member facing the contact target is configured to have a gap portion inside the inner diameter and outside the outer diameter. Therefore, when the elastic member comes into contact with the contact object, it can be deformed both inside and outside, and the deformable volume can be increased.

(Claim 7)
In addition to the configuration according to claim 1, the holding portion may be insulative.

In this case, even if the elastic member has isotropic conductivity, the contact member is anisotropically conductive in the thickness direction in order to ensure insulation from the adjacent elastic member. Sex is realized. In order to impart anisotropy to the conductivity, it is necessary to orient the material responsible for the conductivity or to disperse the material by appropriately controlling the distance between the materials. For this reason, the manufacturing process becomes complicated, leading to a decrease in productivity. In this regard, if the holding portion is made insulating, an isotropic conductive member with high productivity can be used. Therefore, the contact sheet having such a configuration realizes a narrow pitch and a long life, and further has high productivity.
In addition, when the holding | maintenance part of a board | substrate is insulating and has an electroconductive area | region in the circumference | surroundings, the crosstalk in an adjacent elastic member is suppressed by grounding this electroconductive area | region.

(Claim 8)
In addition to the configuration according to claim 1, the elastic member may have anisotropic conductivity in the thickness direction of the substrate, and the holding portion may be conductive.

  In the case of having such a configuration, the basic function of the contact sheet called anisotropic conductivity in the thickness direction of the substrate is realized by an elastic member, and if the holding part is grounded, it is used as a region for suppressing crosstalk. sell. For this reason, it is easy to secure a crosstalk suppression region even if the pitch is narrowed. Therefore, the contact sheet having such a configuration has good electrical characteristics even at a narrow pitch.

(Claim 9)
In addition to the configuration according to claim 1, the elastic member may have a configuration in which conductive particles and / or whiskers are dispersed in an insulating material having elasticity.
The elastic member having such a configuration can be easily produced as long as it has isotropic conductivity. For example, it is possible to obtain an elastic member having desired conductivity by dispersing a conductive material in a state where the thermoplastic elastomer is heated to exhibit fluidity and cooling the material. Thus, the contact sheet having the elastic member having such a configuration is particularly high in productivity.

  Note that an elastic member having a configuration in which an insulating elastic member is filled in a void portion of a conductive nonwoven fabric can be manufactured with high productivity in the same manner as the elastic member having the configuration according to claim 9.

(Claim 10)
In addition to the configuration according to claim 1, the elastic member has a cylindrical shape, and a plurality of linear and / or strip-like conductors penetrate through the upper and lower surfaces of the cylindrical shape in an insulating material having elasticity. You may have the structure arrange | positioned.
The elastic member having such a configuration can exhibit anisotropic conductivity in the thickness direction of the substrate, and the basic function of the contact sheet can be realized only by the elastic member. Therefore, it is possible to increase the degree of freedom in designing the substrate and increase the productivity, or to provide conductivity and a substrate having a countermeasure against crosstalk. Therefore, according to such a configuration, a contact sheet having not only a narrow pitch and a long life but also a higher added value is realized.

  The conductor may have a certain tilt angle with respect to the thickness direction of the substrate. In this case, it is easy to be deformed in a certain direction when coming into contact with the contact object, and the possibility that the conductor is buckled is reduced. Moreover, mutual arrangement | positioning in several conductors may be substantially parallel, and may mutually differ and may have a contact point. If they are parallel, disconnection due to interference between conductors is unlikely to occur, and if they have contact points, there are multiple conductive paths, so local disconnection of conductors causes loss of conductivity as an elastic member. It is difficult to reach.

(Claim 11)
In addition to the structure which concerns on Claim 10, the exposed part from the upper and lower surfaces of the elastic member in a conductor may have a structure which protrudes from an elastic member.
Since the elastic member having such a configuration is in contact with a contact target such as a bump and a wiring board such as an inspection circuit at the protruding portion, contact failure is unlikely to occur. For this reason, the reliability as a contact sheet is high, and therefore, such a configuration contributes to a long life.

(Claim 12)
In addition to the configuration according to claim 10, the plurality of linear and / or strip-shaped conductors are wound around the elastic core member while being spaced apart from adjacent conductors, and have a gap portion. The elastic material which comprises a layer and has an insulating elastic coating layer around this electric conductor layer, and the elastic material which constitutes this elastic coating layer may have the composition arranged also at the crevice part of an electric conductor layer. .
In such a configuration, since the conductor is disposed at a predetermined tilt angle with respect to the thickness direction of the substrate, it is difficult to buckle even by contact with the contact target. In addition, since it is wound, it is deformed so as to narrow the distance between adjacent conductors when contacting. For this reason, it is difficult to cause a situation in which the elastic member, which is a concern when the linear conductors are inclined and aligned in a certain direction, is largely deformed only in a predetermined direction as the conductor is deformed. Therefore, it is easy to cope with a narrow pitch.

Further, since the insulating elastic coating layer is disposed around the conductor as the outermost layer of the elastic member, anisotropic conductivity in the thickness direction of the substrate is realized as the conductive member. For this reason, it is also possible to use a conductive member as the substrate. In addition, this elastic coating layer prevents the conductors wound around from dropping off before the elastic member is held on the substrate, and contributes to maintaining the quality of the elastic member.
Furthermore, since the insulating elastic material constituting the elastic coating layer is also disposed in the gap between adjacent conductors, the deformation of the individual conductors is restricted to some extent by the elastic material. For this reason, it is difficult to generate a situation where some of the conductors are extremely deformed and buckled due to contact with the contact object.

  Thus, by having the structure of Claim 12, the contact sheet | seat which suppressed crosstalk highly is implement | achieved, making narrow pitch and long life compatible at a high level. In addition, since the quality of the elastic member alone is not easily deteriorated, the quality of the contact sheet is also stable.

(Claim 13)
The contact sheet manufacturing method according to the present invention provided to achieve the above object is a core member in which an elastic layer made of a first elastic body is formed around a wire capable of withstanding a predetermined tension to form a core member. A forming step, a conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip-like conductors around the core member, and a core member and the conductor layer. The first elastic body is removed from a part of the cable strip to form an exposed area where the conductor is exposed, and the cylindrical shape is formed by cutting the conductor in the exposed area and removing the wire from the core member. The elastic member forming step of forming the elastic member, and a plurality of through holes having an outer diameter substantially equal to the outer diameter of the elastic member are provided. Bullet to be engaged with the member And a member holding step.

  According to this configuration, it is possible to obtain the contact sheet according to claim 2 having the elastic member according to claim 10. Such a contact sheet can not only achieve both a narrow pitch and a long life as described above, but also can provide high added value such as crosstalk suppression.

  Here, as the core member forming step, for example, a wire immersed in a liquefied thermoplastic elastomer is pulled up while passing through an aperture having a predetermined opening diameter, so that a first elasticity corresponding to the opening diameter is obtained. Forming the body layer is realized.

Further, the conductor layer forming step is realized based on a wire mesh manufacturing technique used in a coaxial cable manufacturing technique.
The exposed region forming step is a step of selectively removing the elastic layer disposed between the conductor layer and the wire. This step can be easily realized by making the material of the first elastic body greatly different from the material of the conductor and the wire. For example, if the conductor and wire are made of a metal such as copper and the first elastic body is an organic substance such as urethane, only the first elastic body can be removed thermally or chemically. Specific examples include laser processing such as YAG laser, carbon dioxide laser, and excimer laser, immersion in an appropriate solvent, and dissolution by solvent spraying.

Even when an elastic coating layer to be described later is formed, selective removal can be realized in the same manner if the material of the second elastic body constituting the elastic coating layer is an organic material.
In the subsequent elastic material forming step, the conductor is cut and the wire is removed in the exposed region.

First, regarding the cutting operation, either mechanical cutting or physicochemical cutting may be performed.
When performing mechanical cutting, the elastic layer and the conductor layer are not connected at the same time, but only the conductor is cut. Therefore, the elastic layer is difficult to adhere to the cutting tool. Cable breakage and abnormal tool wear are less likely to occur. Needless to say, abnormal wear of the tool causes a reduction in machining accuracy and a decrease in productivity. In addition, since the elastic member is likely to escape during processing, if the elastic layer and the conductor layer are cut at the same time, the conductor is likely to be buried in the cut surface, but this phenomenon is unlikely to occur because only the conductor layer is cut. As a result, the electrical connection as the contact sheet contributes to the improvement in stability. Further, since the elastic body does not adhere to the cross section of the elastic body due to the shearing force during processing, the occurrence of defects (plating defects or poor conductivity) due to the adhesion is prevented. This also contributes to stabilization of the electrical connection of the contact sheet.

On the other hand, when performing physicochemical cutting, a laser such as a YAG laser may be used.
When the elastic body in the exposed region is cut in this way, the elastic member formed by laminating the elastic layer and the conductor layer is continuously provided on the wire at a predetermined interval (this interval is defined by the width of the exposed region). A cable structure that is arranged in a bead shape is formed. Since this cable structure is an aggregate of elastic members, the elastic members can be individually taken out by holding the elastic members arranged at the ends and pulling them out from the wires.
The pulling-out operation of the elastic body may be set based on the micro manipulation technique used in the assembly technique of the microparts as in the subsequent elastic member holding process.

(Claim 14)
In the above manufacturing method, an elastic coating layer forming step of forming an elastic coating layer made of a second elastic body having insulation between the conductor layer forming step and the elastic member forming step around the conductor layer. You may prepare.

According to such a manufacturing method, since the elastic covering layer by the second elastic body layer is insulative, it is possible to manufacture an elastic member having anisotropic conductivity in the thickness direction of the substrate. In addition, this elastic coating layer prevents the conductor disposed so as to fall off. For this reason, the yield fall resulting from conductor drop-off in an elastic member formation process or an elastic member holding process is controlled, and it contributes to productivity improvement as a contact sheet.
In addition, this elastic coating layer forming process may be manufactured by a pulling process from a liquid thermoplastic elastomer in the same manner as the core member forming process, or by using a powder coating technique or an extrusion molding technique. Also good.

(Claim 15)
In the manufacturing method according to claim 14, in the conductor layer forming step, adjacent conductors are wound apart to form a void in the conductor layer, and the second elastic body is formed in the void. You may provide the elastic material introduction process to arrange | position.

According to this manufacturing method, it is possible to manufacture the contact sheet having the configuration according to claim 12. According to such a configuration, as described above, a contact sheet that realizes both a narrow pitch and a long life while suppressing crosstalk is realized.
The elastic material introduction step may be the same step as the elastic coating layer forming step or may be a separate step. In the case of the same process, the viscosity of the elastic body supplied in the elastic coating layer forming process may be lowered so as to extend around the conductor. On the other hand, when the process is different from the process of coating the elastic body, the second elastic body formed in the elastic coating layer forming process may be reduced in viscosity by heating, for example, so as to extend around the conductor. And after forming a cable piece, you may supply an elastic material to the space | gap part of a conductor layer from the cross section.

(Claim 16)
In the manufacturing method according to claim 13, in the elastic member forming step, the conductor in the exposed region may be cut so as to form a protruding portion from which the conductor protrudes from the end surface of the elastic member.

In the contact sheet based on such a manufacturing method, since this protrusion comes into contact with a contact object or a circuit board, the electrical connection is stabilized.
Note that when the conductor is cut using a laser, the cut portion can be formed into a bump shape by adjusting the processing conditions. As a result, an elastic member having bumps formed on the protruding portion is obtained, and the contact sheet having such an elastic member further stabilizes the electrical connection with the contact object and the circuit board.

Moreover, it is good also considering the shape of a protrusion part as bump shape by performing a plating process to the protrusion part formed by the said cutting | disconnection. Also in this case, similarly to the bump-like protrusions formed by the laser, the electrical connection with the contact object or the circuit board is stabilized. As a specific method of the plating process, for example, a plurality of elastic members may be placed in the barrel to perform the electroless plating process.
If further noted from the viewpoint of stabilization of electrical connection, a conductive layer may be further improved by forming a gold plating layer on the protruding portion after cutting or bump-like processing.

(Claim 17)
A contact sheet manufacturing method according to the present invention provided to achieve the above object is a core member in which an elastic layer made of a first elastic body is formed around a wire capable of withstanding a predetermined tension to form a core member. A forming step, a conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip-like conductors around the core member, and a core member and the conductor layer. A cable piece forming step of forming a cable piece by cutting the cable into a predetermined length, and a wire for removing the wire from the cable piece to form a cylindrical elastic member having an elastic layer and a conductor layer The removing step and engaging the elastic member with the plate-like member by inserting the elastic member into the through-hole of the plate-like member having a plurality of through-holes having an outer diameter substantially equal to the outer diameter of the elastic member. An elastic member holding step.

  According to this configuration, it is possible to obtain the contact sheet according to claim 2 having the elastic member according to claim 10. Such a contact sheet can not only achieve both a narrow pitch and a long life as described above, but also can provide high added value such as crosstalk suppression.

  Note that the cable piece forming step is realized based on a cutting technique of a composite material of an elastic body and a metal. The wire removal process and the elastic member holding process may be set based on the micro manipulation technique used in the assembly technique of the minute parts.

(Claim 18)
In the above manufacturing method, in the wire removing step, the cable piece from which the wire has been removed may be further cut into an elastic member.
In such a manufacturing method, the cable piece having the maximum length capable of removing the wire is cut in the cable piece forming step, and the cable after the wire is removed in the wire removing step is cut again to an appropriate length as a conductive elastic member. For this reason, the number of wire removal operations can be reduced to ½ or less than that of the manufacturing method according to claim 17. Considering that the outer diameter of the cable piece is in sub-millimeter units and that the outer diameter of the wire is in the order of several tens of μm, the number of wire removal operations can be reduced to half or less, which not only shortens manufacturing time but also reduces process failures. Reduce occurrence. Therefore, it is realized that the production efficiency is improved by adopting such a process.

(Claim 19)
In the manufacturing method according to claim 17, the elastic layer may be formed after the intermediate layer having lubricity is formed around the wire.
In such a manufacturing method, since the wire is efficiently removed, defects in the wire removal process are unlikely to occur. Therefore, it is realized that the production efficiency is improved by adopting such a process. Further, when combined with the manufacturing method according to claim 18, it is realized that the length of the cable piece is set longer, and as a result, the number of wire removal operations is further reduced, and the production efficiency is further increased.

  Note that “having lubricity” means not only when the shear stress at the contact interface between the wire and the first elastic layer and the intermediate layer is low, but also within the intermediate layer than the wire and the first elastic layer. This includes cases where breakage is likely to occur. Therefore, as a material having lubricity for forming the intermediate layer, a fluorine-containing material such as PTFE (polytetrafluoroethylene) or PVDF (polyvinylidene fluoride) may be used. A foamable material in which capsules are dispersed may be used.

(Claim 20)
In the manufacturing method according to claim 17, in the conductor layer forming step, adjacent conductors are wound apart to form a void in the conductor layer, and the conductor layer forming step and the cable piece forming step are performed. An elastic covering layer forming step of forming an insulating covering layer made of a second elastic body having an insulating property around the conductor layer, and an elastic material introducing step of disposing the second elastic body in the gap And may be provided.
According to this manufacturing method, the cross-talk can be achieved while the conductive elastic member having anisotropic conductivity in the thickness direction of the substrate is manufactured with high productivity, and both the narrow pitch and the long life are achieved. As described above, a contact sheet that suppresses the above is realized.
The elastic material introducing step may be the same step as the elastic covering layer forming step or may be a separate step as described above.

(Claim 21)
21. The manufacturing method according to claim 20, wherein a plating protrusion is formed between the wire removing step and the elastic member holding step so that plating is formed in a bump shape on the conductor of the conductor layer exposed on the end face of the elastic member. A process may be provided.

  In the elastic member subjected to the elastic coating layer forming step, the conductor is exposed only at the cylindrical end face. Therefore, when plating is performed on the elastic member, a plating layer is formed only on the exposed conductor, and the shape thereof becomes a bump shape protruding from the elastic layer and the elastic coating layer. By having such a shape, the contact with the contact object or the circuit board is stabilized. Therefore, the contact sheet manufactured by such a manufacturing method stably exhibits the anisotropic conductivity which is a basic function.

  In addition, as a plating process, you may throw in a some elastic member in a barrel and may perform an electroless-plating process, for example.

(Claim 22)
The manufacturing method according to claim 17 may include a conductor projecting step of removing the elastic material at the end of the cylindrical elastic member to project the conductor.
Since the elastic body is cut in the cable piece forming step, there is a possibility that the conductor is buried at the end face or the elastic body is attached to the tip of the conductor as described above. However, according to such a manufacturing method, the structure in which the conductor protrudes from the elastic member can be stably obtained by removing the first elastic body and the second elastic body constituting the end of the elastic member. Realized.

  The protruding portion may be used as a protruding portion as a contact portion or a contact portion with respect to the circuit board, or the protruding portion may be plated in order to realize a more stable electrical connection. When bump-shaped plating is formed so as to wrap the protruding portion by the plating process, the strength as the protruding portion is improved and the contact object and the circuit board are suppressed from being damaged. Instead of the plating treatment, the tip of the protruding portion using a laser may be locally melted to form a bump shape. Also in this case, the strength of the protruding portion is improved and the contact object and the circuit board are prevented from being damaged.

(Claim 23)
A cable, which is an intermediate for producing a contact sheet provided to achieve the above object, is formed by forming an elastic layer made of a first elastic body around a wire that can withstand a predetermined tension, and a core member. A core member forming step, a conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip-shaped conductors around the core member, and a core member and the conductor layer. An exposed region forming step for forming an exposed region where the conductor is exposed by removing the first elastic body from a part of the cable-shaped strip, and a conductor cutting step for cutting the conductor in the exposed region. It is manufactured by a manufacturing method.
The cable is a precursor for obtaining the elastic member according to claim 10, and if the wire is removed from the cable, an elastic member for forming a contact sheet that achieves both a narrow pitch and a long life is realized. Is done.

(Claim 24)
The elastic member, which is an intermediate for manufacturing the contact sheet provided to achieve the above object, is obtained by removing the wire from the cable according to claim 23.
If such an elastic member is engaged and held in each through hole of a substrate having a plurality of through holes, a contact sheet that achieves both a narrow pitch and a long life can be realized.

(Claim 25)
A cable, which is an intermediate body for manufacturing a contact sheet provided to achieve the above object, includes a first elastic body through an intermediate layer having lubricity around a wire that can withstand a predetermined tension. A core member forming step of forming an elastic layer to form a core member; and a conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip-shaped conductors around the core member. It is manufactured by a manufacturing method.
Such a cable is a precursor for obtaining the elastic member according to claim 10, and if the cable is cut to an appropriate length and the internal wire is removed, both a narrow pitch and a long life can be achieved. Thus, an elastic member for forming a contact sheet in which crosstalk is highly suppressed is realized.

(Claim 26)
For the cable, in the conductor layer forming step, adjacent conductors are wound apart to form a void in the conductor layer, and as a subsequent step of the conductor layer forming step, a second insulating layer is provided. You may manufacture by the manufacturing method provided with the elastic coating layer formation process which forms the elastic coating layer which consists of an elastic body around a conductor layer, and the elastic material introduction | transduction process which arrange | positions a 2nd elastic body in a space | gap part.
If the cable is cut to an appropriate length and the internal wire is removed, an elastic member is formed to form a contact sheet with a high level of crosstalk while achieving both a narrow pitch and a long service life. Is done.

(Claim 27)
An elastic member, which is an intermediate for producing the contact sheet according to the present invention provided to achieve the above object, cuts the cable according to claim 25 or 26, and connects the wire from the obtained cable piece. Removed.
If such an elastic member is engaged and held in each through hole of a substrate having a plurality of through holes, a contact sheet that achieves both a narrow pitch and a long life can be realized.

  As described above, according to the present invention, the elastic member capable of expressing the anisotropic conductivity in the thickness direction, which is the basic function of the contact sheet, is carried by the elastic member, the position of the elastic member is ensured, and the mechanical characteristics are secured. Since the above-mentioned function is carried by the substrate having the holding portion, and the holding portion enables the elastic member to be attached and detached, a contact sheet having both a narrow pitch and a long life can be provided.

  Further, the volume modulus of elasticity of the substrate should be lower than the volume modulus of elasticity of the elastic member, the holding part should be a protruding locking point provided in the through hole, or the substrate should be a laminated structure of a plurality of plate members. Thus, since the deformable volume of the elastic member can be increased, it is possible to obtain a contact sheet in which contact with the contact object is stabilized.

  Furthermore, by forming the elastic member into a cylindrical shape and having a conductor that penetrates the upper and lower surfaces while being wound in the cylindrical shape, an elastic member that is less likely to cause positional fluctuations even when contacted with a contact target is obtained. By having a member, a contact sheet corresponding to a narrow pitch can be obtained.

  Furthermore, the holding part of the substrate may be a through-hole structure or a protruding structure protruding from the substrate, or a manufacturing method for manufacturing a conductive elastic member from a cable in which a predetermined member is laminated around the wire may be adopted. Thus, it is possible to obtain a contact sheet with high productivity while achieving both narrow pitch and long life.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments.

[Embodiment 1]
FIG. 1 conceptually shows one embodiment of a contact sheet according to the present invention.
FIG. 2 conceptually shows a cross-section at the arrowed portion of the contact sheet shown in FIG.
A contact sheet 11 in FIG. 1 is a plate-like substrate 12 having elasticity, a cylindrical shape that is engaged and held in each of a plurality of through holes provided in the substrate 12, and a cylindrical elastic member 13 in FIG. Is provided. The elastic members 13 are exposed on the upper surface and the lower surface of the contact sheet 11, respectively, and their arrangement corresponds to the arrangement of the BGA in a contact target, for example, a semiconductor chip or an IC package.

Next, the configuration of the contact sheet 11 will be described in detail with reference to FIG.
The elastic member 13 includes an elastic core member 14, a conductive layer 15 made of a conductive material provided around the elastic core member 14, and an insulating elastic coating layer 16 provided around the conductive layer 15. ing. By the structure of the conductive layer 15 and the elastic coating layer 16, anisotropic conductivity in the thickness direction of the contact sheet is achieved.

  Since the conductive layer 15 can be elastically deformed as described later, the elastic member 13 functions as an elastic body as a whole. Here, the bulk elastic modulus of the entire elastic member 13 is set to be higher than the volume elastic modulus in the vicinity of the through hole 17 of the substrate 12.

  For this reason, when the elastic member 13 having an outer diameter slightly larger than the inner diameter of the through hole 17 is inserted into the through hole 17, the inner wall portion of the through hole 17 is elastically deformed inside. The elastic member 13 is held against the substrate 12 by the entire outer surface by the elastic recovery force of the inner wall portion of the through hole 17.

  When held in this way, within a range where the elastic recovery of the inner wall portion of the through-hole 17 is effective, if the elastic member 13 is deformed by external pressure, for example, pressing by a contact target, the through-hole is allowed to be deformed. When the inner wall of the hole 17 is deformed and the external pressure is released, the original state is restored.

  On the other hand, when the shearing force based on the external pressure exceeds the interfacial shear stress between the inner wall portion of the through-hole 17 and the elastic member 13 generated based on the holding force by the inner wall portion of the through-hole 17, the elastic member 13 is removed from the through-hole 17. take off.

  At this time, by setting the material of the substrate 12 so that the shear stress of the inner wall portion of the through hole 17 is higher than the interfacial shear stress, the through hole 17 is not damaged by dropping of the elastic member 13, and a new elastic property is obtained. The member 13 can be similarly held.

Next, the contact state between the contact sheet 11 and the contact target will be described in detail with reference to FIG.
FIG. 3 is a cross-sectional view conceptually showing a state in which the contact sheet according to the present invention is pressed and contacted by a solder bump as an example of a contact target.

  The semiconductor device 30 having the semiconductor chip 31 and the plurality of solder bumps 32 is in press contact with the contact sheet 11 on which the plurality of elastic members 13 are arranged in an arrangement corresponding to the arrangement of the solder bumps.

  At this time, since the elastic member 13 is an elastic body as a whole, it is compressed in the thickness direction of the contact sheet by the contact pressure and expands in the in-plane direction. Here, since the volume modulus of elasticity of the substrate 12 is lower than the volume modulus of elasticity of the elastic member 13, the inner wall portion of the through hole 17 of the substrate 12 is preferentially compressed in response to the expansion of the elastic member 13, and one elastic member 13. It is suppressed that the influence of the expansion due to is exerted on other adjacent elastic members 13.

  Here, it is particularly preferable that the volume elastic modulus of the core member 14 is set lower than the volume elastic modulus of the elastic coating layer 16. In this case, since the core member 14 is preferentially compressed in the thickness direction of the contact sheet, the cylindrical conductive layer 15 on the outer side thereof narrows the diameter of the cylinder in the contact area with the solder bump 32 that is a contact target. For this reason, the end of the conductive layer 15 is likely to bite into the solder bumps 32, and the electrical connection is stabilized.

Subsequently, the structure of the conductive layer 15 of the elastic member 13 will be described in detail with reference to FIGS. 4 and 5.
FIG. 4: is the perspective view (a) which showed notionally the one aspect | mode (one direction winding) of the elastic member based on this invention, and sectional drawing (b) in the arrow part in a perspective view.

5A and 5B are a perspective view conceptually showing another aspect (bidirectional winding) of the elastic member according to the present invention and a cross-sectional view taken along an arrow in the perspective view.
4 and 5, the conductive layer 15 has a structure in which a plurality of linear and / or strip-shaped conductors are wound around the core member 14 with the adjacent conductors spaced apart from each other. It arrange | positions so that the elastic material which comprises the elastic coating layer 16 may fill with the clearance gap between conductors.

  Thus, since each conductor is spiral and the conductor layer 15 as a whole has a cylindrical shape, it is realized to have elasticity in the vertical direction of the cylindrical shape. Further, by arranging the conductor so as to surround the core member 14, the conductor 15 is uniformly compressed and deformed when it receives a compressive force in the vertical direction, and deforms so as to fall down in either direction. Hateful.

  In addition, since the elastic material disposed in the gap between adjacent conductors gently defines the position of the conductor, some conductors are excessively deformed and buckled when compressed by the contact object. Things are hard to happen.

  Furthermore, the conductor which comprises the conductive layer 15 has the protrusion part which the edge part in the up-down direction of a cylindrical shape protruded from the core member 14 or the elastic coating layer 16 (for example, 42 and 43 of FIG. 4). This protrusion stabilizes the contact with the contact object (for example, solder bump) and the circuit board.

4 and 5, the detailed structure of the conductor is different.
In FIG. 4, the conductor 41 is wound around the core member 14 in one direction and has a multiple helical structure. Here, when the conductor has a spiral structure, there is a concern that the impedance is lowered when a high-frequency signal flows through the conductor. In such a case, as shown in FIG. 4, it is possible to mitigate this effect by setting the pitch of the spiral longer than the thickness of the elastic member, preferably 4 times or more. In FIG. 4A, the conductor 41 is wound around the core member 14 at a pitch four times that of the elastic member 13 as indicated by a dotted line.

  On the other hand, in FIG. 5, the conductor 51 is wound around the core member 14 in both directions to form a braided body. In this braided body structure, since a plurality of conductors as elements are in contact with other conductors, the impedance reduction that is a concern in the one-way winding structure as shown in FIG. 4 is unlikely to occur. In FIG. 5 (a), as shown by the dotted line (51a) and the broken line (51b), the conductor almost makes a round in the elastic member 13. However, as shown in FIG. The conductor layer 15 is in contact with the body multiple times and forms a network structure as the conductor layer 15.

Here, the material of the constituent members of the contact sheet 11 will be described.
First, the elastic core member 14 and the elastic coating layer 16 constituting the elastic member 13 mainly have an elastic polymer. This polymer may be a thermoplastic elastomer such as styrene (SBC), olefin (TPO), vinyl chloride (TPVC), urethane (PU), ester (TPEE), amide (TPAE), or nitrile. Rubber (NBR), hydrogenated nitrile rubber (HNBR), fluorine rubber (FKM, FFKM), acrylic rubber (ACM), silicone rubber (VMQ, FVMQ), urethane rubber (AU, EU), ethylene propylene rubber (EPM, EPDM) ), Chloroprene rubber (CR), chlorosulfonated polyethylene (CSM), epichlorohydrin rubber (CO, ECO), natural rubber (NR), isoprene rubber (IR), styrene butadiene rubber (SBR), butadiene rubber (BR), many Rubbers such as sulfurized rubber (T) and norbornene rubber (NOR) may be used. Alternatively, a mixture of these may be used. Furthermore, the deformable volume may be adjusted by imparting foamability. Hereinafter, as an example, description will be made assuming that thermoplastic urethane is used as the first elastic body.

  When the size of the component is reduced, the thermoplastic elastomer is preferred for manufacturing reasons. Further, the core member 14 and the elastic covering layer 16 may be made of the same material or different materials. As described above, it is preferable that the bulk modulus of the core member 14 is lower than that of the elastic coating layer 16. When this is realized, a different material is used.

  Next, the conductor constituting the conductive layer 15 is a material having low resistivity and suitable for signal conduction, and can be made of metal even if it can be elastically deformed according to the deformation of the elastic polymer material described above. Ceramics may be used, or conductive fine particles dispersed in an insulating material or a conductive polymer may be used.

  Specific examples of the metal include copper, a copper alloy, and tungsten. Copper is particularly excellent in conductivity, and copper alloys such as copper tin alloy and copper silver alloy are more advantageous than copper and advantageous when the wire diameter is several tens of μm. Tungsten is particularly strong, so it can be used with a wire diameter of about 10 μm. Hereinafter, description will be made assuming that a copper tin alloy is used as a conductor as an example.

  Note that by reducing the shape of the conductor from a linear shape to a band shape, in other words, a foil shape or a ribbon shape, it is possible to reduce the thickness of the conductor layer while maintaining strength and conductive characteristics. This contributes to reducing the diameter of the entire elastic member 13 and facilitates the reduction of the contact sheet pitch. For example, in the case of a wire, what required a diameter of 30 μm can be made into a ribbon-like shape with a width of about 10 μm.

  Moreover, the protrusion part of the conductor 15 may be comprised with said electroconductive material which comprises the conductor 15, and may be comprised with the metal material by other electroconductive materials, for example, plating. . In addition, it is desirable that a gold plating layer is formed on the outermost surface from the viewpoint that this projecting portion is a site for electrical connection.

  Subsequently, the material constituting the substrate 12 will be described. In the present embodiment, since the elastic member 13 has the insulating elastic coating layer 16, the elastic member 13 alone realizes anisotropic conductivity in the thickness direction of the contact sheet 11. Therefore, any material may be used for the substrate 12 as long as the elastic material has a lower volume modulus of elasticity than the elastic member 13. Of course, as with the core member 14 and the elastic coating layer 16 that are constituent members of the elastic member 13, an insulating elastic body or a conductive elastic body may be used.

In the case of conductivity, it is possible to prevent electrical crosstalk between the adjacent elastic members 13 by grounding the substrate 12.
In this case, only the electrode corresponding to the arrangement of the elastic member 13 is formed on the surface of the circuit board facing the contact sheet 11 and the wiring is formed on the lower layer other than the surface or on the opposite surface. Is required.

  On the other hand, when the substrate 12 is insulative, electrical conduction in the in-plane direction is prevented by the substrate 12, so the elastic member 13 may not have the elastic coating layer 16. If the pitch is reduced, the elastic covering layer 16 may be omitted in order to reduce the outer diameter of the elastic member 13, and in this case, such a material is advantageous. Note that the entire substrate 12 does not have to be insulative, as long as an insulating layer is formed around the conductive member 13, and other regions may be conductive. In the case of conductivity, it is advantageous because crosstalk is suppressed as described above.

Then, an example of the manufacturing method of the contact sheet 11 which concerns on this embodiment is demonstrated using FIG.
FIG. 6 is a diagram conceptually illustrating an example of a contact sheet manufacturing method according to one embodiment of the present invention.

(Core member forming process)
First, as shown in FIG. 6A, a wire 61 that can withstand a predetermined tension is prepared. Here, the “predetermined tension” is a tension applied to the wire when a plurality of strands are wound by a braiding device as will be described later. As a material of the wire 61, a copper wire or the like generally used as a central material of a coaxial cable may be used. Since a tension is more important than conductivity unlike a coaxial cable, a stainless alloy or tungsten may be used. The outer diameter is determined based on the strength of the wire 61 and the outer diameter of the elastic member 13, and is set in the range of 1/3 to 1/10 of the outer diameter of the elastic member 13 as a guide. If this range is exceeded, workability will be reduced or the conductor inside the elastic member 13 will be easily buckled. As an example, when the outer diameter of the elastic member 13 is 500 μm, the diameter of the wire is 100 μm.
Subsequently, an elastic layer 62 made of a first elastic material is formed on the wire 61 to form the core member 14. FIG. 6B conceptually shows a cross section of the core member 14.
In this coating process, when the first elastic material is a thermoplastic material, the material may be heated to lower the viscosity and supplied to the surface of the wire 61, and the temperature may be lowered to solidify. Specifically, it may be passed through a bath containing a liquid thermoplastic material, or the wire 61 may be brought into contact with the solid thermoplastic material while being heated to an appropriate temperature by electric heating or the like. Alternatively, the thermoplastic material attached to the surface of the wire as powder may be melted by temporary heating of the wire 61, and then the wire 61 may be cooled and solidified. Alternatively, a liquid monomer as a precursor of the first elastic material may be supplied to the surface of the wire 61 and polymerized by heat or light.

  In addition, since the typical thickness of the elastic layer 62 is about 100 micrometers, manufacturing with the following method is especially preferable. That is, an aperture having a predetermined inner diameter (for example, 100 μm) is passed while pulling up the wire 61 from a thermoplastic elastomer bath adjusted to have a predetermined viscosity. By manufacturing in this way, it is easy to control the core member 14 to a predetermined thickness. In addition, it is a particularly preferable manufacturing method to obtain the core member 14 by extruding a thermoplastic elastomer having an appropriate thixotropy while the wire 61 is contained from an aperture having a predetermined inner diameter.

(Conductor layer forming process)
A conductor layer 15 made of a conductive braided body is formed around the core member 14 manufactured by the core member forming step. The forming method may use a braiding device known in the manufacture of coaxial cables. FIG. 6C conceptually shows how the braided body is formed around the core member.
That is, the wire 61 is moved in one direction (upward in the drawing) while applying a predetermined tension, and the plurality of conductive strands 63a and 63b are wound around the core member 14 while alternately rotating in opposite directions at the same time. Thus, the conductor layer 15 made of a conductive braided body is formed.

  Here, the conductors wound in the same direction, that is, the conductive strands are wound while being separated from each other, and a gap is generated between the adjacent strands so that the conductor layer 15 has a void portion. As will be described later, an elastic material enters the gap, and as a result, the elastic recovery force of the conductor layer is increased and the breakage of the conductor is suppressed.

  In this embodiment, the conductor layer 15 is a braided body, but the conductor may be wound only in one direction. In this case, the conductor layer 15 is composed of multiple helical bodies as shown in FIG.

  In the case of using the braiding apparatus described above, a part or all of the conductor may be used in a strip shape, that is, a foil, which may be wound alternately or in one direction. Although the strip-shaped conductor is inferior to the linear elastic body in terms of ease of elastic deformation, it is suitable when the elastic member 13 has a small amount of elastic deformation because it has excellent conductive performance and high strength.

  Furthermore, after the conductor layer 15 is formed, a primer layer is formed on the surface of the conductor with a silane coupling agent or the like to improve the wettability with an elastic material that is an organic substance. The process proceeds efficiently and is particularly suitable.

(Elastic coating layer forming process)
Subsequently, an elastic covering layer 16 made of an insulating elastic body is formed around the conductor layer 15. FIG. 6D conceptually shows a cross section of a cable in which an elastic coating layer 16 is formed around the conductor layer 15.
The elastic covering layer 16 may be formed by using a known technique as in the method of forming the elastic layer 62, but the second elastic material constituting the elastic covering layer 16 in relation to the elastic material introducing step described later. The material is preferably a thermoplastic elastomer and a material capable of sufficiently reducing the viscosity.

  The thickness is preferably set according to the electrical characteristics that the contact sheet as a finished product should have. In particular, when the substrate 12 is conductive, the thickness at which the high frequency characteristics are optimal can be determined in relation to the dielectric constant of the material.

(Elastic material introduction process)
As the second elastic material in the elastic coating layer forming step, a thermoplastic elastomer that softens at a lower temperature than the first elastic material is used, and the elastic coating layer 16 is formed by passing through the melt of the elastomer. In this case, since the second elastic material enters the void portion of the conductor layer 15 when this layer is formed, the elastic material introduction process also proceeds simultaneously.
FIG. 8 conceptually shows before and after this process, FIG. 8A is before the process, and FIG. 8B is after the process. A second elastic material is filled in the conductor layer 15, and an elastic covering layer 16 is formed so as to cover the conductor layer 15.

Thus, performing the elastic coating layer forming step and the elastic material introducing step at the same time contributes to simplification of the process.
On the other hand, when the second elastic material cannot be softened at a lower temperature than the first elastic material, the conductive material constituting the conductive layer 15 is energized after the elastic coating layer 16 is formed. The second elastic material may be introduced into the conductor layer 15 by heating and raising only the ambient temperature.

(Exposed area forming process)
When the cable composed of the elastic layer 62, the conductor layer 15, and the elastic covering layer 16 is thus formed on the wire 61, the first and second elastic bodies are removed from a part of the belt-like portion of the cable, and FIG. An exposed region 64 is formed where the conductor and wires are exposed as shown in e).
Since the exposed region 64 is a cutting position in the next process, the width of the exposed region 64 is determined in consideration of the length of the protruding portion 66 and the cutting margin in both cable pieces formed by cutting. Moreover, since the space | interval which forms the exposure area | region 64 is the length of a cable piece, it respond | corresponds to the thickness of the contact sheet 11 substantially.

  Here, the elastic body may be removed using a known means. For example, it may be removed physicochemically using an excimer laser, or physically (thermally) removed using a carbon dioxide gas laser or a YAG laser. Alternatively, the cable may be partially brought into contact with an appropriate solvent that dissolves the elastic body, such as chloroform, tetrahydrofuran, or carbon disulfide, and dissolved.

(Elastic member forming process)
When the exposed area is thus formed in the cable, only the conductor is cut using the exposed area as a cutting site. Then, as shown in FIG. 6 (f), the wire 61 and the plurality of elastic members 13 are arranged, and the plurality of elastic members 13 are continuously arranged in a bead shape with their centers penetrating the wires 61. A body (hereinafter referred to as a “beaded structure”) 65 is obtained.
The cutting method may be a mechanical cutting means such as a wire saw, a rotary blade, or a push-cut cutter. However, if the cutting is performed using a laser, the elastic member 13 is damaged due to the cutting. It is hard to do and is suitable. What is necessary is just to determine the kind and irradiation condition of a laser according to the conductor which is a cutting object.

  In the case of cutting with a laser, it is preferable to adjust the processing conditions so that the cut end portion of the conductor protrudes from the elastic member 13 to form the protruding portion 66. This protrusion 66 stabilizes the contact with the contact object and the circuit board, and improves the reliability as a contact sheet. Further, it is particularly desirable to adjust the processing conditions so that the protrusion 66 has a bump shape, since the contact with the contact object is further stabilized.

When the wire 61 is pulled out from the bead-like structure 65 thus obtained, the elastic member 13 having the hollow portion 68 as shown in FIG. 6G is obtained.
When the wire 61 is pulled out, the load on the elastic member 13 is alleviated by pulling out the wire while energizing and heating the wire to soften the elastic layer 62.

  It is possible to cut the wire 21 without pulling it out and use it as the elastic member 13. However, the wire 61 is not easy to recover and compressively deform in the thickness direction of the elastic member 13, so pull it out. It is better to leave it.

(Elastic member holding process)
First, as shown in FIG. 6H conceptually showing the cross-sectional structure, a plurality of through holes 69 are formed in an insulating plate-like elastic body to form a substrate 12. This through hole 69 corresponds to the arrangement of the contact object such as a solder bump. In the present embodiment, the diameter of the through hole 69 is set to be approximately equal to the diameter of the elastic member 13, but may be slightly smaller (10 to 30 μm). The difference between the diameter and the aperture is a factor that determines the holding force of the elastic member 13 by the substrate 12 together with the elastic modulus of the elastic member 13 and the substrate 12.
The through-hole 69 can be formed by using known punching means such as punching, drilling, and laser. However, when drilling by machining, a cable piece forming step, which will be described later, is used to ensure high shape accuracy. Similarly, it is desirable to perform processing in a cooled state.

  Further, instead of drilling the through hole 69, the substrate 12 provided with the through hole 69 may be formed directly by molding. For example, a desired substrate 12 can be obtained by pouring vulcanized liquid rubber into a mold having convex portions corresponding to the through-holes 69, solidifying by proceeding with a crosslinking reaction by heating or the like, and then removing from the mold. Such a molding process is advantageous in that a substrate 12 having a through hole can be easily obtained even with a soft rubber having a low volume modulus of elasticity, in which the machining accuracy is remarkably lowered in the drilling process.

Next, as conceptually shown in cross-sectional structure in FIG. 6 (i), the elastic member is formed inside the through hole 69 so that the central axis of the through hole 69 and the central axis of the elastic member 13 are substantially parallel. 13 is inserted.
At this time, since the bulk modulus of the substrate 12 is lower than the bulk modulus of the elastic member 13, it is preferentially compressed and deformed, and the elastic member 13 is held by the subsequent elastic recovery force as already described.

Thus, the contact sheet 11 is manufactured and disposed between the contact object and the circuit board, and exhibits appropriate elasticity and anisotropic conductivity.
Next, another example in the method for manufacturing the contact sheet 11 according to the present embodiment will be described with reference to FIG.

FIG. 7 is a diagram conceptually illustrating another example in the method for manufacturing a contact sheet according to one embodiment of the present invention.
In the following description, differences from an example of the manufacturing method described with reference to FIG. 6 (hereinafter referred to as “first manufacturing example”) will be mainly described.

(Core member forming process)
First, as shown in FIG. 7A, the point that the wire 61 that can withstand a predetermined tension is prepared is the same as that in the first manufacturing example, but the intermediate layer 70 is formed around the wire 61. Is different.
The intermediate layer 70 is used to increase the length of a cable piece to be removed when the wire 61 is removed in a wire removing process described later. If this purpose can be achieved, the intermediate layer 70 is desirably thin. As a typical example, the thickness of the intermediate layer 70 is 10 μm.
The material of the intermediate layer 70 may be a general fluorine-based material as a lubricating material, or may be a soft resin such as paraffin. Alternatively, microcapsules encapsulating paraffin may be dispersed in a resin.

In addition, the process should just employ | adopt the same means as the case where the elastic layer 62 is formed.
Subsequently, an elastic layer 62 made of a first elastic material is coated on the wire 61 on which the intermediate layer 70 is formed to form the core member 14. FIG. 7B conceptually shows a cross section of the core member 14.

(Conductor layer forming process)
The conductor layer 15 is formed as in the first manufacturing example (see FIG. 7C).
(Elastic coating layer forming process)
The elastic coating layer 16 is formed as in the first production example (see FIG. 7D).
(Elastic material introduction process)
The elastic material introduction step is the same as in the first production example.
(Cable piece forming process)
Subsequently, the cable on which the elastic covering layer 16 is formed is cut to obtain a cable piece 71 as shown in FIG. The length is set longer than the thickness of the contact sheet 11.
A known method may be used for the cutting method, and a wire saw, a rotary blade, or a push-cut cutter may be used.
However, since the mixture of the elastic body and the metal is cut with high precision when the exposed region forming step is not performed, it is necessary to set the cutting conditions appropriately. In addition, when the bulk modulus is low and deformation is likely, pretreatment such as cooling the cable with liquid nitrogen once to reduce its elastic behavior and then cutting may be necessary.
Further, as a cutting method, cutting using a laser instead of cutting with a cutting tool may be performed. In this case, the cutting end portion of the conductor can be formed into a bump shape by adjusting the processing conditions, and when the bump shape is formed, a plating protrusion forming step described later may be omitted.

(Wire removal process)
When the wire 61 is pulled out from the cable piece 71 thus obtained, a wireless cable piece 72 as shown in FIG. 6F is obtained. When this wireless cable piece 72 is cut according to the thickness of the contact sheet, a small cable piece 73 as shown in FIG. 6G is obtained.

  When the wire 61 is pulled out, the longer the length of the target cable, the smaller the number of wire removal steps and the more the productivity is improved. Therefore, for example, the wire 61 may be pulled out while being electrically heated to soften the intermediate layer 70.

If the intermediate layer 70 remains in the hollow portion 68 after the wire 61 is pulled out, and the residue affects the reliability of the contact sheet 11, ultrasonic cleaning is performed in an appropriate solvent. What is necessary is just to remove this.
Of course, it is possible to cut the wire 21 without pulling it out and use it as the elastic member 13. However, since the wire 61 is not easy to recover and compressively deform in the thickness direction of the elastic member 13, pull it out. It is better to leave it.

(Conductor protrusion process)
The end of the cable piece 73 thus obtained is subjected to physical and chemical treatment to remove the first and second elastic bodies at the end. As a result, the volume of the conductor exposed from the cable piece 73 increases, and it becomes easy to perform the plating process in the next step.
Here, if the thickness of the elastic coating layer 16 is increased in advance and the entire elastic body 13 is etched, the productivity is increased, not only the end portion is processed. For example, the first elastic body or the second elastic body may be removed by putting a plurality of cable pieces 73 into the barrel and immersing them in an appropriate solvent or exposing them to corrosive plasma. .

(Plating protrusion forming process)
When the conductor is appropriately exposed from the end face of the cable piece 73 in this manner, this is put into an electroless nickel plating bath to form a nickel plating layer on the exposed conductor. The shape becomes a bump shape, and becomes a projecting portion 74 that is in contact with a contact target or a circuit board. In order to further improve the electrical conduction characteristics, a gold plating layer may be further formed on the protrusion 74 made of nickel plating.
Thus, the elastic member 13 excellent in electrical connection is manufactured.
Note that, when tungsten is used as the conductor, such a plating process may be omitted because high electrical conduction characteristics can be obtained with only the conductor.

(Elastic member holding process)
A process similar to that of the first embodiment is performed on the elastic member 13 manufactured through the above-described process, and the contact sheet 11 is obtained.

[Embodiment 2]
Then, 2nd embodiment of the contact sheet which concerns on this invention is described using FIG.
FIG. 9 is a top view (a) conceptually showing a second embodiment of the contact sheet according to the present invention, and a cross-sectional view (b) taken along the arrow in the external view (a).
In this embodiment, a plurality of protrusions 91 (91a, 91b) are formed on the inner surface of the through hole 269 of the substrate 212. Here, the protrusion 91 is formed such that the diameter of the inscribed circle that contacts the most protruding portion of the plurality of protrusions 91 is smaller than the outer diameter of the elastic member 213. For this reason, when the elastic member 213 is inserted into the through hole 269, the elastic member 213 is held against the substrate 212 with the protrusion 91 as a locking point.

  At this time, the volume elastic modulus of the protrusion 91 is set lower than the volume elastic modulus of the elastic member 213, and the protrusion 91 may be elastically deformed to hold the elastic member 213, or conversely 91 is harder, and the elastic member 213 may be elastically deformed and held.

  When the substrate 212 including the protruding portion 91 is harder, the substrate 212 may be formed of a hard material, for example, an inorganic material such as a hard resin or glass, or a metal. In the case of a hard material, the processing accuracy can be increased as compared with an elastic material. Therefore, it is advantageous when the pitch is narrowed.

In the case of a metal material, the crosstalk of the electric signal flowing through the conductor of the elastic member 213 is suppressed by grounding the entire substrate.
The shape of the protrusion 91 is not limited to a shape in which a part of a sphere as shown in FIG. 9 protrudes from the inner surface of the through hole 269, and may be any shape as long as the function of holding the elastic member 213 can be achieved. For example, the shape may be a key groove or a rib, or may be a ring shape. Alternatively, irregular irregularities such as satin may be formed on a part or the entire surface of the inner surface of the through-hole 269.

  The shape as shown in FIG. 9 can be realized by using a molding technique if the material is resin, and the ring shape can be dealt with by adjusting the depth at the time of spot facing. The rib shape can be realized by punching, and the satin shape can be realized by sandblasting the through hole.

  The inner surface other than the protrusion 91 of the through-hole 269 may have a void area that does not come into contact with the elastic member 213 as shown in FIG. 9, or it is in contact with the elastic member 213 over almost the entire inner surface. Also good. When there is a void area, it is possible to ensure a large deformable volume of the elastic member 213, and when there is no void area, the elastic member 213 is unlikely to shift in the in-plane direction of the contact sheet.

[Embodiment 3]
Subsequently, a third embodiment of the contact sheet according to the present invention will be described with reference to FIG.
FIG. 10 is a cross-sectional view (a) conceptually showing an example of the third embodiment of the contact sheet according to the present invention and a cross-sectional view (b) conceptually showing another example.
In the embodiment according to FIG. 10A of the present embodiment, the substrate 312 has a configuration in which the relative positions are substantially fixed in a state where the two plate materials 101 and 102 are separated at a predetermined interval. The through holes 103 and 104 have substantially the same diameter. The diameters of the elastic members 313 are set to be substantially the same or slightly narrower, and the ends of the elastic members 313 are fitted and fixed to the respective members.

  In this configuration, the intermediate portion of the outer surface of the elastic member 313 is not restrained. For this reason, when it contacts with a contact object, this part deform | transforms preferentially and absorbs the press from a contact object. Therefore, the plate materials 101 and 102 do not need to have remarkable elasticity, and a hard material such as a resin plate or a metal plate may be used.

  The space between the two plate members 101 and 102 is an air layer in this embodiment, but may be filled with an elastic material. In addition, a spacer may be interposed in order to appropriately maintain the separation distance. Further, the relative positions of the two plate members 101 and 102 may be fixed, but the elastic member 313 may be a substantial spacer. That is, when the relative position between the plate members is substantially fixed by making the insertion depth of the elastic member 313 into the through holes 103 and 104 substantially constant, and the elastic member 313 is in contact with the contact object and is compressed and deformed, The deformation may be absorbed by the deflection of the plate material.

Next, an embodiment according to FIG. 10B will be described.
In this case, the point that the substrate 312 is configured by the two plate members 111 and 112 is the same as the configuration according to FIG. 10A, but in the case of the present embodiment, the through holes 113 and 114 and Have different opening diameters.

  The inner diameter of the through-hole 114 opposite to the side facing the contact target is set to be substantially the same as or slightly narrower than the outer diameter of the elastic member 313, like the through-holes 103 and 104 according to FIG. A member 313 is inserted. However, the inner diameter of the through hole 113 on the side facing the contact target is formed wider than the outer diameter of the elastic member 313, and the elastic member 313 held in the through hole 114 is loosely fitted to the through hole 114. It has become a state.

  That is, since the end portion of the elastic member 313 facing the contact target is not compressed by the substrate 312, the deformable volume of this portion can be the original volume of the elastic member 313. The opening edge portion of the through hole 114 is adjacent to the elastic member when the elastic member 313 undergoes deformation that expands or moves in the in-plane direction of the contact sheet in accordance with the contact with the contact target. It plays a role of defining a movable upper limit for preventing contact with 313.

  In this embodiment, the plate members 111 and 112 require a fixing member at an appropriate spacer or plate member end portion in order to maintain the relative position.

[Embodiment 4]
Then, 4th embodiment of the contact sheet which concerns on this invention is described using FIG. 11 and FIG.
FIG. 11 is a perspective view conceptually showing a fourth embodiment of the contact sheet according to the present invention. In the upper half of the drawing, the substrate structure 121 according to this embodiment is shown, and in the lower half of the drawing, A state 122 in which the elastic member 413 is held and becomes a contact sheet is shown.

FIG. 12 is a sectional view conceptually showing a fourth embodiment of the contact sheet according to the present invention.
In the substrate 412 according to this embodiment, through electrodes 123 for electrically connecting the upper and lower surfaces of the substrate are formed corresponding to the array to be contacted. And the protrusion 124 thinner than the outer diameter is formed in the exposed part 125 of the side facing the contact object of this penetration electrode 123, As a result, the shape of the exposed part 125 is donut shape. Note that the protrusion 124 is fixed by being partially embedded in the through electrode 123 in FIG.

  On the other hand, the elastic member 413 is manufactured by the manufacturing method (FIG. 6 or FIG. 7) described in the first embodiment. For this reason, a hollow portion 468 derived from wire removal is formed in the central portion of the elastic member 413. Since the diameter of the hollow portion 68 is set to be substantially equal to the outer diameter of the protrusion 124, the elastic member 413 is engaged with the substrate 412 when the protrusion 124 is inserted into the hollow portion 68. Then, the exposed portion 125 comes into contact with the bump-shaped protrusion 66 (projecting portion 74) of the elastic member 413, and the bump-shaped projection 66 (projecting portion 74) that protrudes from the end surface of the elastic member 413 facing the contact target and the through electrode. The exposed surface 126 on the side facing the circuit board 123 is electrically connected, and anisotropic conductivity as the contact sheet 411 is realized.

  Since the protrusion height of the protrusion 124 is set to be shorter than the thickness of the elastic member 413, the hollow portion 68 remains at the end of the elastic member 413 on the side facing the contact target. Due to the presence of the hollow portion 68, the elastic layer 62 disposed inside the conductive layer of the elastic member 413 is easily deformed to the inner diameter side so as to narrow the hollow portion 68 when contacting the contact target. Due to this deformation, the bump-like protrusion 66 (projection 74) formed at the end of the conductive layer falls to the center side and comes into contact with the contact object. Therefore, a contact state is stabilized and the quality as a contact sheet improves.

  The material of the protrusion 124 may be conductive or insulating. However, in the case of a conductive material, particularly a metal, current welding or ultrasonic welding is possible, and it is particularly preferable because the protrusion 124 does not need to be embedded as shown in FIG.

  The contact sheet of the present invention can set the number of repeated use of the contact sheet to be high even if the object to be inspected has a fine pitch. Moreover, if the elastic member of a component is replaced, it is not necessary to discard the entire contact sheet even if there is a partial conductivity failure. Therefore, it contributes not only to improving the reliability of the process using the contact sheet, for example, the inspection process, but also to resource saving, which is preferable from the viewpoint of environmental activities.

  Moreover, when this contact sheet is manufactured by the manufacturing method according to the present invention, the contact sheet can be obtained while realizing high productivity.

1 is a perspective view conceptually showing one aspect of a contact sheet according to the present invention. It is sectional drawing which showed notionally the cross section in the part of the arrow of the contact sheet shown by FIG. Sectional drawing which showed notionally the state by which the contact sheet which concerns on this invention is press-contacted by the solder bump as an example of contact object. They are the perspective view (a) which showed notionally the one aspect | mode (one direction winding) of the elastic member which concerns on this invention, and sectional drawing (b) in the arrow part in a perspective view. They are the perspective view (a) which showed notionally the other aspect (bidirectional winding) of the elastic member which concerns on this invention, and sectional drawing in the arrow part in a perspective view (b). It is the figure which showed notionally an example of the manufacturing method of the contact sheet which concerns on one of the embodiments of this invention. It is the figure which showed notionally another example in the manufacturing method of the contact sheet which concerns on one of the embodiments of this invention. It is sectional drawing shown notionally about the case where an elastic covering layer formation process and an elastic material introduction | transduction process are performed simultaneously, and an elastic member is manufactured. It is the top view (a) which showed notionally 2nd embodiment of the contact sheet which concerns on this invention, and sectional drawing (b) of the arrow part of external view (a). It is sectional drawing (a) which showed conceptually an example of 3rd embodiment in the contact sheet which concerns on this invention, and sectional drawing (b) which showed conceptually another example. It is the perspective view which showed conceptually 4th embodiment of the contact sheet which concerns on this invention. It is sectional drawing which showed notionally 4th embodiment of the contact sheet which concerns on this invention. The conceptual diagram of the cross section in the metal wire embedding type contact sheet concerning a prior art. The conceptual diagram of the cross section in the metal particle type contact sheet concerning a prior art.

Explanation of symbols

11 Contact Sheet 12 Substrate 13 Elastic Member 14 Core Member 15 Conductor Layer 16 Covering Layer

Claims (27)

An elastic member capable of developing electrical conductivity;
A substrate including a plurality of holding portions capable of individually engaging the elastic members,
The contact portion is configured to detachably engage and hold the elastic member. The holding portion is a plurality of through holes provided in the substrate,
The contact sheet according to claim 1, wherein at least a part of the elastic member is engaged with the substrate by being fitted into the through hole.   The contact sheet according to claim 2, wherein a volume elastic modulus of the holding portion is lower than a volume elastic modulus of the elastic member. The through-hole has a protruding locking point in the hole,
The contact sheet according to claim 2, wherein the elastic member is held in the through hole by the locking point. The substrate is formed by laminating a plurality of plate materials having a bulk modulus higher than that of the elastic member,
The contact sheet according to claim 1, wherein the plate member includes a through hole, and the elastic member is engaged with the substrate using at least one of the through holes as the holding portion. The holding part is a plurality of protrusions provided on the substrate,
The contact sheet according to claim 1, wherein the elastic member is engaged with the substrate by inserting the protrusion into the elastic member.   The contact sheet according to claim 1, wherein the holding portion is insulative.   The contact sheet according to claim 1, wherein the elastic member has anisotropic conductivity in a thickness direction of the substrate, and the holding portion is conductive.   The contact sheet according to claim 1, wherein the elastic member includes conductive particles and / or whiskers dispersed in an insulating material having elasticity.   2. The elastic member has a cylindrical shape, and a plurality of linear and / or belt-like conductors are disposed in an insulating material having elasticity so as to penetrate the upper and lower surfaces of the cylindrical shape. Contact sheet.   The contact sheet according to claim 10, wherein exposed portions of the conductor from the upper and lower surfaces of the elastic member protrude from the elastic member. The plurality of linear and / or strip-shaped conductors are wound around the core member having elasticity while being spaced apart from the adjacent conductors to form a conductor layer having a gap,
An insulating elastic coating layer around the conductor layer;
The contact sheet according to claim 10, wherein the elastic material constituting the elastic coating layer is also disposed in a gap portion of the conductor layer. A core member forming step in which an elastic layer made of a first elastic body is formed around a wire capable of withstanding a predetermined tension to form a core member;
A conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip conductors around the core member;
An exposed region forming step of forming an exposed region in which the first elastic body is removed from a part of the cable-shaped portion including the core member and the conductor layer to expose the conductor;
An elastic member forming step of forming a cylindrical elastic member by cutting the conductor in the exposed region and removing the wire from the core member;
A plurality of through-holes having an outer diameter substantially equal to the outer diameter of the elastic member are provided, the elastic member is fitted into the through-hole of the plate-like member having elasticity, and the elastic member is engaged with the plate-like member. A contact sheet manufacturing method comprising: an elastic member holding step. An elastic covering layer forming step of forming an elastic covering layer made of a second elastic body having insulation between the conductor layer forming step and the elastic member forming step. 14. A method for producing a contact sheet according to 13. In the conductor layer forming step, the adjacent conductors are wound apart to form a void in the conductor layer,
The contact sheet manufacturing method according to claim 14, further comprising an elastic material introducing step of disposing the second elastic body in the gap. The contact sheet manufacturing method according to claim 13, wherein in the elastic member forming step, the conductor in the exposed region is cut so as to form a protruding portion from which the conductor protrudes from an end surface of the elastic member. A core member forming step in which an elastic layer made of a first elastic body is formed around a wire capable of withstanding a predetermined tension to form a core member;
A conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip conductors around the core member;
A cable piece forming step of forming a cable piece by cutting a cable having the core member and the conductor layer into a predetermined length;
A wire removing step of forming a cylindrical elastic member having the elastic layer and the conductor layer by removing the wire from the cable piece;
A plurality of through-holes having an outer diameter substantially equal to the outer diameter of the elastic member are provided, the elastic member is fitted into the through-hole of the plate-like member having elasticity, and the elastic member is engaged with the plate-like member. A contact sheet manufacturing method comprising: an elastic member holding step. The contact sheet manufacturing method according to claim 17, wherein in the wire removing step, the cable piece from which the wire has been removed is further cut into the elastic member. The contact sheet manufacturing method according to claim 17, wherein, in the core member forming step, the elastic layer is formed after forming an intermediate layer having lubricity around the wire. In the conductor layer forming step, the adjacent conductors are wound apart to form a void in the conductor layer,
An elastic covering layer forming step of forming an elastic covering layer made of a second elastic body having insulation between the conductor layer forming step and the cable piece forming step; and The contact sheet manufacturing method according to claim 17, further comprising an elastic material introducing step of disposing a second elastic body in the gap. 21. The contact sheet according to claim 20, further comprising a plating protrusion forming step of forming a plating on the conductor exposed on the end face of the elastic member between the wire removing step and the elastic member holding step. Production method. The contact sheet manufacturing method according to claim 17, further comprising a conductor protruding step of removing the elastic material at an end of the cylindrical elastic member to protrude the conductor. A core member forming step in which an elastic layer made of a first elastic body is formed around a wire that can withstand a predetermined tension to form a core member;
A conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip conductors around the core member;
An exposed region forming step of forming an exposed region in which the first elastic body is removed from a part of the cable-shaped portion including the core member and the conductor layer to expose the conductor;
A cable for forming a contact sheet, which is manufactured by a manufacturing method including a conductor cutting step of cutting the conductor in the exposed region.   An elastic member for forming a contact sheet, wherein a wire is removed from the cable according to claim 23. A core member forming step for forming a core member by forming an elastic layer made of a first elastic body through an intermediate layer having lubricity around a wire capable of withstanding a predetermined tension;
A contact sheet manufactured by a manufacturing method comprising a conductor layer forming step of forming a conductor layer by winding a plurality of linear and / or strip-shaped conductors around the core member. Cable to form. In the conductor layer forming step, the adjacent conductors are wound apart to form a void in the conductor layer,
As a subsequent step of the conductor layer forming step, an elastic coating layer forming step of forming an elastic coating layer made of a second elastic body having insulation around the conductor layer; and 26. A cable for forming a contact sheet according to claim 25, wherein the cable is produced by a production method comprising an elastic material introduction step arranged in a gap. Cutting the cable according to claim 25 or 26;
An elastic member for forming a contact sheet, wherein the wire is removed from the obtained cable piece.

Images