KR20100010830A - Elastic conductive sheet and manufacturing method thereof - Google Patents

Abstract

PURPOSE: An elastic conductive sheet having an adjacent conductive unit and insulating unit and a manufacturing method thereof are provided to make the elastic conductive unit flow electrically only into the thickness direction without electrical interference. CONSTITUTION: Each conductive unit(12) surrounds with a partition wall(22) consisting of an electrical insulating material to keep an insulated state with the adjacent conductive unit. The partition wall is consisted of one of acryl, PC, PET, a silicon and ceramic fiber and/or a metal mesh applying with an insulative material. The partition wall has a height lower than the material(11) thickness. The partition wall is installed in the intermediate area of the material.

Description

Elastic conductive sheet and manufacturing method of the elastic conductive sheet

The present invention relates to an elastic conductive sheet and a method of manufacturing the same, and more particularly, to an elastic conductive sheet and a method for manufacturing the same, in which a plurality of conductive portions made of conductive particles oriented in the thickness direction are divided by adjacent conductive portions and partition walls. It is about.

Generally, an electrical test is performed to determine whether a semiconductor device that has been manufactured is defective. Specifically, a predetermined test signal is sent from the test apparatus to the semiconductor device to determine whether the semiconductor device is short-circuited. The test apparatus and the semiconductor device are not directly connected to each other, but are indirectly connected by using a so-called test socket. As such a test socket, a variety of pogo pins and the like can be used. Recently, an elastic conductive sheet has been mainly used.

One example of such an elastic conductive sheet is shown in FIG. The elastic conductive sheet 100 has a form in which a plurality of conductive particles 121 are contained in the substrate 110 made of an insulating elastic material. The plurality of conductive particles 121 are arranged in the thickness direction to form one conductive portion 120, and the conductive portions 120 are arranged in the surface direction so as to correspond to the terminals 141 of the semiconductor device 140. Will be. The edge portion of the elastic conductive sheet 100 is fixed by the frame 130.

In the state in which the elastic conductive sheet 100 is mounted on the test apparatus 150, the respective conductive portions 120 are in contact with the pad 151 of the test apparatus 150. After that, as shown in FIG. 2, when the semiconductor device 140 is lowered, the terminal 141 of the semiconductor device 140 contacts each conductive portion 120 and presses the conductive portion 120. Accordingly, the conductive particles 121 in the conductive portion 120 are in close contact with each other to form a state that can be energized. Subsequently, when a predetermined test signal is applied from the test apparatus 150, the test signal is transmitted to the semiconductor device 140 via the elastic conductive sheet 100, and the reflected signal is reversely tested through the elastic conductive sheet 100. It enters the device 150.

When the elastic conductive sheet 100 is pressed in the thickness direction, it has a property of exhibiting conductivity only in the thickness direction, and since mechanical means such as soldering or springs are not used, it is excellent in durability and can achieve simple electrical connection. There is this. In addition, since it can absorb mechanical shocks and deformations, there is an advantage that the smooth connection is possible, it is widely used for electrical connection with various electrical circuit devices and test devices.

The method of manufacturing the elastic conductive sheet 100 will be described with reference to FIGS. 3 and 4. First, as illustrated in FIG. 3, molding in which the conductive particles 121 are distributed in the flowable elastic material 110a is performed. The molding material is prepared, and the molding material is inserted into predetermined molds 161 and 162. After being inserted into the molds 161 and 162, a magnetic field is applied in the thickness direction in the mold so that the conductive particles 121 can be arranged in the thickness direction as shown in FIG. After the conductive particles 121 are arranged, the conductive particles 121 are gradually cured to complete the elastic conductive sheet 100.

The elastic conductive sheet according to the prior art has the following problems.

In the elastic conductive sheet, the magnetic field plays an important role in the orientation of the conductive particles. In the prior art, which depends on such a magnetic field, the narrower the gap between the conductive parts, the more problematic the reliability becomes.

In other words, as the interval between magnetic fields applied in the thickness direction becomes narrower, they interfere with each other, making it difficult to form conductive parts having a uniform arrangement of a desired shape. FIG. 5 illustrates an elastic conductive sheet in which conductive particles are irregularly oriented when the gap between conductive portions is narrowed.

As such, when the elastic conductive sheet in which the electrical flow is to be made only in the thickness direction is electrically contacted with an adjacent conductive portion (see “C” in FIG. 5) and a signal flows in the surface direction, a problem in the reliability of the test is caused. In particular, a problem occurs such that a test signal to be applied to a terminal of a specific semiconductor device is not applied to a desired terminal. This is particularly problematic in semiconductor devices where the pitch between the terminals is 0.5 mm or less.

The present invention has been made to achieve the above object, to provide an elastic conductive sheet and a method for manufacturing the elastic conductive sheet, the conductive portion of the elastic conductive sheet to enable electrical flow only in the thickness direction without electrical interference with each other. For the purpose of

The present invention has been made to solve the above technical problem, and more specifically, the conductive particles contained in the substrate made of an insulating elastic material is provided with a plurality of conductive parts extending in the thickness direction, elasticity having conductivity in the thickness direction In the conductive sheet, each conductive portion is surrounded by a partition wall made of an insulating material so as to be insulated from the adjacent conductive portion.

In the elastic conductive sheet, the partition wall is preferably made of any one material of acrylic, PC, PET, silicon, ceramic fibers and metal mesh coated with an insulating material.

In the elastic conductive sheet, the partition wall preferably has a height lower than the thickness of the substrate.

In the elastic conductive sheet, the partition wall is preferably provided in the intermediate region of the substrate.

An elastic conductive sheet according to the present invention for solving the above-described technical problems, has a plurality of conductive portions in which the conductive particles contained in the substrate made of an insulating elastic material is stretched in the thickness direction, the elastic conductive having conductivity in the thickness direction In the sheet, it includes a insulating member formed in a sheet form, the through hole penetrating the upper surface and the lower surface in the thickness direction corresponding to the conductive portion, the insulating member is contained in the substrate, Corresponding conductive portions are inserted into the respective through holes.

In the elastic conductive sheet, the through hole preferably has a polygonal cross-sectional shape.

It is preferable that the said elastic conductive sheet is arrange | positioned between a test subject and a test apparatus.

In the manufacturing method of the elastic conductive sheet according to the present invention for achieving the above object, in the manufacturing method of the elastic conductive sheet having conductivity in the thickness direction, preparing a molding material in which the conductive particles are distributed in the flowable elastic material Making;

Inserting the molding material into a mold;

Allowing the conductive member to be inserted into the through hole by immersing the insulating member having the through hole penetrating in the up and down direction in the molding material; And hardening the molding material.

In the manufacturing method, after the solidifying step, it is preferable to further include a step of pulling the hardened molding material in the surface direction in order to narrow the distance between the conductive particles.

In the manufacturing method, it is preferable to further include a magnetic field applied to the molding material in the thickness direction between the step of being inserted and the solidifying step.

In the elastic conductive sheet according to the present invention, each conductive portion is surrounded by a partition wall that maintains an insulated state from an adjacent conductive portion, so that the distance between the conductive portions is narrowed, thereby maintaining a reliable electrical insulation state in the plane direction. There is an advantage that the reliability of the test can be increased.

Hereinafter, the elastic conductive sheet according to the present invention will be described in detail with reference to the accompanying drawings.

6 is a plan view of an elastic conductive sheet according to a preferred embodiment of the present invention, Figure 7 is a cross-sectional view of Figure 6, Figures 8 and 9 shows a state of performing an electrical test using the elastic conductive sheet of Figure 6 Drawing.

The elastic conductive sheet 10 according to the present invention is disposed between a test object (including various electronic components such as a semiconductor device, a PCB substrate, and an FPCB) and a test apparatus. Specifically, the terminal 141 of the test object 140 and the pad 151 of the test apparatus 150 are electrically connected to each other. Specifically, the electric flow in the thickness direction is allowed, and It is designed not to allow electric flow in the surface direction perpendicular to the thickness direction. The elastic conductive sheet 10 is disposed between the inspected object 140 and the test apparatus 150, and the terminal 141 of the inspected object 140 has a 0.5 mm pitch (distance between the terminals 141). It can also be used if you have

In the elastic conductive sheet 10, a plurality of conductive portions 12 conductive in the thickness direction are disposed in the substrate 11 made of an insulating elastic material. Each of the conductive parts 12 may be disposed at the same interval as the terminal 141 at a position corresponding to the terminal 141 of the inspected object 140, or may be disposed at a smaller interval than the terminal 141. . In addition, the elastic conductive sheet 10 contains an insulating member 20.

The insulating elastic material used as the base material 11 is preferably a heat resistant polymer material having a crosslinked structure as the elastic polymer material. Although various things can be used as curable polymeric substance formation material which can be used in order to obtain such a crosslinked polymeric substance, Liquid silicone rubber is preferable.

The liquid silicone rubber may be an addition type or a condensation type, but an addition type liquid silicone rubber is preferable. This addition type liquid silicone rubber is cured by the reaction of a vinyl group and a Si-H bond, and is a one-component type (one-component type) consisting of a polysiloxane containing both a vinyl group and a Si-H bond, and a polysiloxane containing a vinyl group. And a two-component (two-component) composed of polysiloxane containing a Si-H bond, but in the present invention, it is preferable to use a two-component addition type liquid silicone rubber.

As addition liquid silicone, it is preferable to use the thing of the viscosity in 23 degreeC of 100-1,250 Pa.s, More preferably, it is 150-800 Pa.s, Especially preferably, it is 250-500 Pa.s. When this viscosity is less than 100 Pa.s, sedimentation of the electroconductive particle 13 in the said addition type | mold liquid silicone rubber tends to occur, favorable storage stability cannot be obtained, and electroconductive particle when a parallel magnetic field is applied to a molding material layer It may become difficult to form the chain | strand of electroconductive particle 13 in a uniform state, without orienting so that (13) may line up in a thickness direction. On the other hand, when this viscosity exceeds 1250 Pa.s, since the obtained molding material becomes a thing with high viscosity, it may become difficult to form a molding material layer in a metal mold | die, and also a parallel magnetic field acts on a molding material layer. Even if it does, the electroconductive particle 13 does not move enough, and it may become difficult to orientate so that the electroconductive particle 13 may be lined up in the thickness direction.

The conductive particles 13 constituting the conductive portion 12 are preferably formed by coating a highly conductive metal on the surface of core particles (hereinafter, also referred to as "magnetic core particles") of a metal material. Here, "highly conductive metal" means that the electrical conductivity at 0 ° C is 5 k 10 ⁶ Ω ¹ m ⁻¹ or more. It is preferable that the number average particle diameter of the core particle for obtaining electroconductive particle 13 (P) is 3-40 micrometers. Here, the number average particle diameter of a core particle means what was measured by the laser diffraction scattering method.

When the said number average particle diameter is 3 micrometers or more, pressurization and deformation are easy and it is easy to obtain the electroconductive part 12 with low resistance value and high connection reliability, and it is preferable. On the other hand, when the said number average particle diameter is 40 micrometers or less, the fine electrically-conductive part 12 for connection can be formed easily, and the electrically-conductive part 12 for connection obtained easily becomes stable thing.

As the material constituting such core particles, iron, nickel, cobalt, a coating of these metals on copper, a resin, or the like can be used. In addition, magnetic material is preferable. Gold, silver, rhodium, platinum, chromium and the like can be used as the highly conductive metal to be coated on the surface of the magnetic core particles, and among these, gold is preferably used because it is chemically stable and has high electrical conductivity.

The insulating member 20 is contained in the base material 11 made of an insulating elastic material, so that each conductive portion 12 can be insulated in the plane direction. The insulating member 20 is formed in a sheet form, but the insulating member 20 has a through hole 21 penetrating the upper and lower surfaces in the thickness direction thereof. The through holes 21 are disposed at positions corresponding to the conductive portions 12 by the number corresponding to the conductive portions 12, and the corresponding conductive portions 12 are inserted into the respective through holes 21. do.

As the conductive parts 12 are inserted into the through holes 21, the conductive parts 12 are distinguished by the adjacent conductive parts 12 and the partition walls 22. That is, each conductive portion 12 is surrounded by a partition wall 22 to be distinguished from the adjacent conductive portion 12 when inserted into the through hole 21.

As such, the partition wall 22 that insulates the conductive portion 12 is preferably made of a material having insulation and a higher melting point than an insulating elastic material. Specifically, it is preferable to use any one material of acrylic, PC, PET, silicon, ceramic fibers and metal mesh coated with an insulating material, but is not limited thereto. It is preferable that the height of such a partition 22 is lower than the thickness of the said base material 11. That is, it is preferable that the thickness of the entire sheet-shaped insulating member 20 is thinner than that of the base material 11, and the insulating member 20 is disposed in an approximately intermediate region of the sheet so that the surface of the base material 11 is not exposed. good. The reason for this is that when the insulating member 20 is made of a harder material than the base 11, the elastic conductive sheet 10 may be reduced in overall elasticity due to the insulating member 20. The through holes 21 each have a rectangular cross-sectional shape.

The manufacturing method of the elastic conductive sheet according to the preferred embodiment of the present invention will be described as follows with reference to FIG.

First, a molding material in which conductive particles are distributed in a flowable elastic material is prepared (S100), and the molding material is inserted into a mold (S110). Subsequently, the insulating member having the through hole penetrating in the vertical direction is introduced into the molding material and submerged in the molding material so that each conductive particle is inserted into the through hole (S120). Thereafter, a magnetic field is applied to the molding material in the thickness direction so that the conductive particles can be arranged in the thickness direction (S130). Thereafter, the molding material is cured (S140) to complete the manufacture of the elastic conductive sheet. On the other hand, in the above production method, the insulating member may be inserted into the mold before inserting the molding material into the mold, and then the molding material may be inserted into the mold.

The elastic conductive sheet according to the preferred embodiment of the present invention has the following effects.

First, as shown in FIG. 8, the fabricated elastic conductive sheet 10 is mounted on the test apparatus 150 so that the pad 151 of the test apparatus 150 may have a conductive portion (10) of the elastic conductive sheet 10. 12). Subsequently, the test object 140 is gradually lowered so that the terminal 141 of the test object 140 is in contact with the upper side of the conductive portion 12 as shown in FIG. 9. Subsequently, a pressing force is provided to the inspected object 140 so that the terminals 141 of the inspected object 140 come into close contact with the conductive portion 12. At this time, the conductive particles 13 are in contact with each other, thereby achieving an electrical conduction state. Thereafter, a signal is applied from the test apparatus 150 to perform a predetermined electrical test.

In the elastic conductive sheet according to the present invention, even when the pitch of the test object is small and the distance between the conductive parts is to be narrowed, the conductive parts are separated by partition walls so that they do not contact each other. Accordingly, no electrical signal flows in the plane direction.

In particular, such a problem is useful in a method of arranging conductive particles by applying a magnetic field, where the magnetic force lines must be close to each other. That is, even when the conductive particles are not uniformly arranged by adjacent magnetic lines, the respective conductive particles are arranged within a predetermined range by the partition wall.

In general, when the terminal of the test object presses the elastic conductive sheet, each conductive portion is pressed in the thickness direction to form a curved shape such as a C or S shape. In such a case, when the distance between the conductive parts is narrow, the conductive parts that are not electrically connected to each other at first may be in contact with each other while being bent in the left and right direction while being pressed and pressed. On the contrary, in this embodiment, since the partitions are separated from each other, there is no fear of such a problem.

The elastic conductive sheet according to the present invention can also be modified as follows.

First, in the above-described embodiment according to FIG. 6, the through hole has a rectangular cross-sectional shape, but the elastic conductive sheet has been described, but is not limited thereto. As shown in FIG. 11, the cross-sectional shape of the through hole 21 is hexagonal. It is also possible to form a variety of polygons, such as triangles, pentagons, .... Of course, various shapes such as other circles can be envisioned.

In addition, the manufacturing method described above includes a step of applying a magnetic field in the thickness direction between the step of being inserted and the step of hardening, it is also possible to solidify as it is without applying a magnetic field. At this time, it will be necessary to keep the height of the partition wall almost similar to the thickness of the sheet so that each conductive portion made of conductive particles is not connected to each other.

On the other hand, in the case of hardening without applying a magnetic field, the particles may not be aligned with each other, the particles may be biased in some parts, or some particles may be too far apart. In view of such a case, in order to narrow the distance between the conductive particles in the same conductive portion, a step of pulling the molding materials hardened together in the plane direction may be added. In the case where the solidified molding material is pulled in the plane direction, the insulating elastic material between the conductive particles is torn and the distance between the conductive elastic materials is kept close to each other to maintain almost contact state.

Although the present invention has been described in detail with reference to Examples and Modifications, the present invention is not necessarily limited to these Examples and Modifications, and may be variously modified and implemented within the scope without departing from the spirit of the present invention. .

1 is a view showing an elastic conductive sheet according to the prior art.

2 is a view for performing an electrical test using the elastic conductive sheet of FIG.

3 and 4 is a manufacturing method of the elastic conductive sheet of FIG.

5 is a view showing an elastic conductive sheet according to the prior art.

6 is a plan view of an elastic conductive sheet according to a preferred embodiment of the present invention.

FIG. 7 is a cross-sectional view taken along line VIII-VIII of FIG.

8 and 9 are views for performing an electrical test using the elastic conductive sheet of FIG.

10 is a flowchart illustrating a method of manufacturing the elastic conductive sheet according to FIG. 5.

11 is a view showing an elastic conductive sheet according to another embodiment of the present invention.

<Detailed Description of Drawings>

10.Elastic conductive sheet 11.

12 ... conductive part 13 ... conductive particles

20 Insulation member 21 Through-hole

22.Bulk

Claims (10)

In the elastic conductive sheet having a plurality of conductive portions extending in the thickness direction of the conductive particles contained in the base material of the insulating elastic material, And each conductive portion is surrounded by a partition wall made of an insulating material so as to maintain an insulated state from an adjacent conductive portion. The method of claim 1, The partition wall is an elastic conductive sheet, characterized in that made of any one material of metal mesh coated with acrylic, PC, PET, silicon, ceramic fibers and insulating material. The method of claim 1, The barrier rib has a height that is lower than the thickness of the substrate. The method of claim 3, The barrier rib is provided in the intermediate region of the base material. In the elastic conductive sheet having a plurality of conductive parts extending in the thickness direction of the conductive particles contained in the substrate made of an insulating elastic material, and having a conductivity in the thickness direction, The insulating member is formed in a sheet shape and has a through hole penetrating the upper and lower surfaces in a thickness direction thereof in a portion corresponding to the conductive portion. The insulating member is contained in the substrate, An elastic conductive sheet, characterized in that a corresponding conductive portion is inserted into each of the through holes. The method of claim 5, The through-hole is an elastic conductive sheet, characterized in that forming a cross-sectional shape of the polygon. The method of claim 5, The elastic conductive sheet is an elastic conductive sheet, characterized in that disposed between the test object and the test device. In the manufacturing method of the elastic conductive sheet having conductivity in the thickness direction, Preparing a molding material in which conductive particles are distributed in the flowable elastic material; Injecting the molding material into a mold; Allowing the conductive member to be inserted into the through hole by immersing the insulating member having the through hole penetrating in the up and down direction in the molding material; And Hardening the molding material; method for producing an elastic conductive sheet comprising a. The method of claim 8, After the hardening step, And pulling the hardened molding material in a plane direction to narrow the distance between the conductive particles. The method of claim 8, And a step of applying a magnetic field in the thickness direction to the molding material between the inserting step and the solidifying step.

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