KR20010085173A - Thermal conductive material - Google Patents

Abstract

PURPOSE: To provide a heat conductive member capable of achieving space saving and miniaturization, capable of efficiently transmitting the heat of a heated pressure bonding plate to an object to be bonded under pressure and having antistatic properties. CONSTITUTION: The heat conductive member consists of a sheet layer 21 comprising a heat conductive sheet and the release layer formed on at least one surface of the sheet layer 21 and at least one of the sheet layer 21 and the release layer 22 has antistatic properties.

Description

Thermally Conductive Member {THERMAL CONDUCTIVE MATERIAL}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a thermally conductive member that is used for crimping joining of electronic and electrical equipment parts and transfers heat from a hot press plate to the compact.

In the bonding of semiconductor chips and semiconductor lead parts, which are widely used in electronic and electrical equipment, a semiconductor bare chip is used inside the connection lead formed on the carrier tape, and the wire bonding method of joining the junction part by thermal compression with a thin metal wire. There are a TAB (tape carrier) method and a flip chip method to be connected.

Among these, the TAB method is widely used for mounting a personal computer or a workstation because automation and high speed assembly are possible.

An anisotropic conductive film capable of coping with a narrow pitch is used for bonding between an outer of a TAB for a liquid crystal display driving LSI and a pixel electrode of a liquid crystal panel. The anisotropic conductive film is obtained by dispersing conductive particles such as metal-plated resin particles in a thermosetting epoxy resin or the like, and is suitable for connection of a narrow pitch display because conductive is obtained through the particles by being compressed.

And bonding of a film carrier (tape carrier with an electronic component) and a liquid crystal panel is performed by the method shown in FIG. 4, for example. That is, the liquid crystal panel 3 having the anisotropic conductive film 2 attached thereto is disposed on the lower plate 1, the film carrier 4 is placed on the anisotropic conductive film 2, and the release heat-resistant film 5 and the thermal conductivity are formed. By pressing and attaching the hot pressing plate 7 through the rubber sheet 6, the heat of the hot pressing plate 7 passes through the thermal conductive rubber sheet 6 to the film carrier 4 and the anisotropic conductive film 2. It transfers and compresses the electroconductive particle in the anisotropic conductive film 2, and joins the anisotropic conductive film 2 and the film carrier 4 together.

However, since the method shown in FIG. 4 needs to set the thermally conductive rubber sheet 6 and the release heat-resistant film 5 so as to overlap each other, for the supply of the heat-conductive rubber sheet 6 and the release heat-resistant film 5, respectively. There is a problem in that a device for winding and a manufacturing facility are enlarged. In addition, the thinner the heat-resistant film 5 has better thermal conductivity, but there is a problem in that wrinkles are generated at the time of setting so that the heat-resistant film 5 cannot be made very thin from the work. In addition, it is disadvantageous in terms of thermal efficiency that the release heat-resistant film 5 cannot be made thin.

As a countermeasure, the present applicant provides a thermally conductive rubber member formed by laminating and integrating a fluorine-based resin layer on one or both surfaces of a thermally conductive rubber sheet (Japanese Patent Laid-Open No. 7-214728). As a result, space saving and miniaturization can be achieved, and the heat of the heat-compression bonding plate 7 can be efficiently transferred to the to-be-compressed body, and the crimping of the electronic and electrical equipment parts can be performed satisfactorily.

However, since the thermally conductive rubber member is an insulator, if it is used repeatedly, there may be a problem that static electricity is generated and the liquid crystal panel 3, which is mounted when the thermally conductive rubber member is removed, may be displaced or a spark may be generated, causing the IC to be destroyed. There is a further improvement required.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and aims to provide a thermally conductive member having an antistatic property while being able to reduce space and size and to efficiently transfer heat from a hot press plate to a press body. It is done.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic explanatory drawing for demonstrating an example of the use aspect of the heat conductive member of this invention,

2 is a cross-sectional view schematically showing one embodiment of the thermally conductive member of the present invention;

3 is a cross-sectional view schematically showing another embodiment of the thermally conductive member of the present invention;

It is typical explanatory drawing for demonstrating the attachment method of the conventional film carrier.

* Explanation of symbols for the main parts of the drawings

21: sheet layer 22: release layer

In order to achieve the above object, the thermally conductive member of the present invention is a thermally conductive member having a sheet layer made of a thermally conductive sheet and a release layer formed on at least one surface of the sheet layer, and at least one of the sheet layer and the release layer. It has a structure having this antistatic property.

That is, since the thermally conductive member of the present invention has a sheet layer made of a thermally conductive sheet and a release layer formed on at least one surface of the sheet layer, the thermally conductive rubber sheet and the mold release agent are used in the manufacture of an article having an IC circuit. Since two sheets of heat resistant film are not required, it can be made possible by one sheet, so that space saving and miniaturization of manufacturing equipment can be realized. In addition, since at least one of the sheet layer and the release layer has antistatic properties, static electricity is not generated by repeated use of the thermally conductive member, the liquid crystal panel to be mounted is displaced, or sparks are generated, resulting in damage to the IC. Does not occur. And when a release layer is provided in one side of a sheet layer, heat-compression with respect to a to-be-adhered body can be performed favorably, without a thermally conductive sheet contacting a to-be-adhered body, and a release layer is formed on both surfaces of a sheet layer. In this case, the thermally conductive sheet is not in direct contact with the hot press plate, but the heat press can be performed even more favorably with respect to the adherend.

In particular, the surface resistance of the antistatic layer is set to 10 ¹⁰ Ω or less, or the release layer is a silicone-based resin layer or a fluororesin layer, particularly as a thermally conductive member for use in the manufacture of an article having an IC circuit. desirable.

Next, embodiment of this invention is described.

The heat conductive member of this invention is equipped with the sheet layer which consists of a heat conductive sheet, and the release layer formed in at least one surface of this sheet layer, At least one of these layers has antistatic property.

The thermally conductive sheet constituting the sheet layer of the thermally conductive member of the present invention is formed by molding a thermally conductive material into a sheet by a conventionally known method. Although a thermally conductive material generally means rubber | gum, resin, etc. which the thermally conductive filler was added, rubber | gum and resin itself may show thermal conductivity. As a thermally conductive material, the composition containing a silicone polymer and a thermally conductive filler, etc. are mentioned, for example.

As said silicone polymer, what can provide elasticity to the sheet layer which consists of a thermally conductive sheet is preferable, For example, silicone rubber, a silicone resin, etc. are mentioned, It can be used individually or in combination of 2 or more types. Especially, silicone rubber is preferable at the point which can provide outstanding elasticity to a sheet layer.

The thermally conductive filler is not particularly limited as long as it can impart thermal conductivity to a sheet layer made of a thermally conductive sheet. For example, aluminum oxide (alumina), boron nitride, aluminum nitride, zinc oxide, magnesium oxide, silicon carbide, quartz And aluminum hydroxide, metal powder, and the like, and can be used alone or in combination of two or more. Especially, aluminum oxide is preferable at the point of the dispersibility in a sheet layer.

The composition containing the silicone polymer and the thermally conductive filler can also be suitably contained a curing agent, a pigment, a reaction regulator, a softener, a filler, a surface treatment agent and the like.

There is no limitation in particular as said hardening | curing agent, According to the kind of silicone polymer to be used, a vulcanization method, etc., it selects suitably. For example, acyl peroxide is used in hot air vulcanization and alkyl peroxide is used in other vulcanizations. It is preferable to set the content rate of a hardening | curing agent in the range of 0.5-3 parts with respect to 100 weight part of silicone polymers (it abbreviates as "part" hereafter).

The release layer which comprises the heat conductive member of this invention is formed using the material which can give mold release property, such as silicone resin and fluorine resin, for example. There is no restriction | limiting in particular as silicone type resin, For example, methyl silicone resin, methylphenyl silicone resin, etc. are mentioned. Moreover, there is no restriction | limiting in particular as fluorine resin, For example, polyethylene fluoride (PTFE), poly ethylene trifluoride (PTFCE), polyvinylidene fluoride (PVDF), etc. are mentioned. Moreover, you may mix | blend binders, such as an epoxy resin, a urethane resin, etc. in the formation material of a mold release layer as needed.

And there is no limitation in particular as a formation method of the said release layer, For example, when using silicone resin, what melt | dissolved silicone resin in the solvent is apply | coated to a thermally conductive sheet, and it dries and hardens a silicone resin film (silicone resin layer) The formation method etc. are employ | adopted. In the case of using a fluorine-based resin, a method of forming a fluorine-based resin film (fluorine-based resin layer) by applying a melted fluorine-based resin in a solvent to a thermally conductive sheet and then drying and curing to form a fluorine-based resin film (fluorine-based resin layer). The method of adhering a resin sheet, etc. are employ | adopted.

In the thermally conductive member of the present invention, at least one of the sheet layer and the release layer has antistatic property as described above.

The surface resistance of the layer having antistatic property is preferably set to 10 ¹⁰ Ω or less, particularly preferably 10 ⁸ Ω or less. In other words, if it exceeds 10 ¹⁰ Ω, the generation of static electricity cannot be prevented, and there is a fear that problems such as disassembly of the liquid crystal panel to be mounted or generation of sparks can not be solved.

As a method of providing antistatic property to the said sheet layer and a mold release layer, the method of mix | blending 1 type, or 2 or more types of a electrically conductive agent, an electroconductive paint, a conductive ink, etc. in the formation material of a sheet layer and a release layer is mentioned, for example. have.

As said electrically conductive agent, metal powders, such as aluminum, copper, nickel, brass, silver, carbon black, etc. are mentioned, It is used individually or in combination of 2 or more types.

Among them, aluminum powder is preferred because it has excellent electrical conductivity and thermal conductivity and is lightweight. The average particle diameter of the metal powder in the conductive agent is preferably set in the range of 3 to 100 µm, particularly preferably in the range of 10 to 50 µm. In other words, when the average particle diameter of the metal powder is less than 3 µm, the sheet layer becomes too hard when dispersed in the sheet layer, and the elasticity of the entire thermally conductive member is inferior. When dispersed in the release layer, when it is mixed in large amounts to obtain the desired electrical conductivity, This is because the release property tends to fall. In addition, when the average particle diameter of the metal powder is dispersed in the sheet layer exceeding 100 μm, the balance between electrical conductivity and thermal conductivity is broken, and when dispersed in the release layer, deviation occurs on the surface of the release layer, thereby providing an IC circuit. This is because it tends to be unsuitable for the manufacture of articles.

The conductive paint is a conductive paint, for example, conductivity-imparting agents (silver powder, silver oxide, silver nitrate, organic compounds of silver, copper powder, nickel powder, carbon black, etc.), and binders (ethyl cellulose, phenol resin, acrylic). Synthetic resins such as resins, low melting glass powders, zinc borate, zinc silicate, vegetable oils, etc. .

The said conductive ink means what is excellent in printability for the purpose of printing.

In addition, the thickness of the sheet layer which comprises the heat conductive member of this invention is normally set in the range of 0.1-5 mm. The thermal conductivity of the sheet layer is preferably set to 0.40 W / m · K or more in terms of thermal efficiency, and particularly preferably 1.00 W / m · K or more.

Moreover, it is preferable that the thickness of the mold release layer which comprises the heat conductive member of this invention is set in the range of 3-50 micrometers, Especially preferably, it is the range of 10-30 micrometers. This is because, if the thickness of the release layer is less than 3 µm, problems tend to occur in mold release properties, and if the thickness of the release layer exceeds 50 µm, problems tend to occur in terms of thermal efficiency.

The thermally conductive member of the present invention is used for the manufacture of articles having IC circuits such as liquid crystal display devices and plasma display panels (PDPs). For example, the thermally conductive member of the present invention can be used as follows. That is, as shown in FIG. 1, the liquid crystal panel 3 with the anisotropic conductive film 2 is mounted on the lower plate 1, and the film carrier 4 is placed on the anisotropic conductive film 2. On the other hand, the heat conductive member 12 is intermittently thrown in from the supply roll 11, and the film carrier 4 and the heat-compression-bonding plate 7 are made so that the release layer 13 of this heat conductive member 12 may become downward. After positioning between and, the anisotropic conductive film 2 and the film carrier 4 are bonded together by pressing the hot pressing plate 7 from above. Subsequently, the thermal conductive member 12 is driven and wound around the winding roll 14 to remove the thermal conductive member 12. In this way, the thermally conductive member of the present invention can be used.

In this way, the use of the thermally conductive member of the present invention eliminates the need for supplying and winding devices for each of the thermally conductive sheet and the release-resistant heat-resistant film as in the prior art, thus making it possible to save space and reduce the size of manufacturing equipment. . In addition, since static electricity is not generated by the sheet layer and the release layer having antistatic property, there is no problem that the mounted liquid crystal panel is displaced or a spark is generated, such that the IC is destroyed.

In addition, although the case where the release layer was formed in one side of the sheet layer which consists of a thermally conductive sheet was demonstrated in the said example (refer FIG. 1), it is not limited to this, The same holds true even when the release layer is formed in both surfaces of the sheet layer. The thermally conductive member of the invention can be used. In this case, the sheet layer is not directly in contact with the hot pressing plate, but it has the advantage that the hot pressing can be performed even better.

Next, an Example and a comparative example are demonstrated.

(Example 1)

As shown in FIG. 2, the heat conductive member of Example 1 is formed by laminating and integrating a silicone resin layer (release layer) 22 on one side of a sheet layer 21 made of a thermally conductive sheet. It has antistatic property and was produced as follows.

That is, firstly, 250 parts of aluminum powder (Toyo Alumina, AC2500, manufactured by Toyo Alumina, AC2500) having an average particle size of 25 µm used as a thermally conductive filler and a conductive agent in 100 parts of a silicone rubber (TSE-221-3u manufactured by Toshiba Silicone Co., Ltd.) (Toshiba Silicone Co., TC-8) A composition containing one part was prepared, and molded into a sheet shape and crosslinked to prepare a thermal conductive sheet having a thickness of 0.2 mm and a thermal conductivity of 1.3 W / m · K.

Next, after apply | coating silicone resin resin (Dore Dow Silicone Co., SR 2316) to one surface of the said heat conductive sheet, the silicone resin layer 22 of thickness 10micrometer was formed by heat-drying at 100 degreeC for 30 minutes. . Thus, the heat conductive member in which the silicone resin layer 22 was formed in one side of the sheet layer 21 which consists of heat conductive sheets was obtained.

(Example 2)

The heat conductive member of Example 2 was made so that the silicone resin layer 22 shown in FIG. 2 might have antistatic property, and it did not have antistatic property with respect to the sheet layer 21, It was produced as follows.

First, 400 parts of aluminum oxide (Showa Denkosha, AS-30), which is a thermally conductive filler, and 100 parts of silicone rubber (manufactured by Toshiba Silicone Co., TSE-221-3u), and a curing agent (manufactured by Toshiba Silicone Co., TC- 8) The composition which mix | blended 1 part was prepared, this was shape | molded in the sheet form, and it bridge | crosslinked, and the thermal conductive sheet which is thickness 0.2mm and heat conductivity 1.2W / m * K was produced.

Next, a silicon-based compound containing 2 weights (mixing ratio in total) of conductive carbon black (made by Mitsubishi Chemical Corporation, Diamond Black # 3150, average particle diameter 26mμ (= nm)) added as a conductive agent to one surface of the thermally conductive sheet. After apply | coating resin resin (SR2316 by Toray Dow Silicone Co., Ltd.), the silicone resin layer 22 of thickness 10micrometer was formed by heat-drying at 100 degreeC for 30 minutes. Thus, the heat conductive member in which the silicone resin layer 22 was formed in one side of the sheet layer 21 which consists of heat conductive sheets was obtained.

(Example 3)

As shown in FIG. 3, the heat conductive member of Example 3 is formed by laminating and integrating silicone resin layers (release layers) 22 and 22 'on both sides of a sheet layer 21 made of a thermal conductive sheet. 22,22 ') has antistatic property and was produced as follows.

That is, the thermal conductive sheet was produced like Example 2 first.

Next, silicone-based resin in which conductive carbon black (Mitsubishi Chemical Co., Ltd., diamond black # 3150, average particle diameter 26mμ (= nm)) 2 weights (mixing ratio in total) was added to both surfaces of the thermally conductive sheet as a conductive agent. After apply | coating paint (SR2316 by Toray Dow Silicone Co., Ltd.), the silicone resin layers 22 and 22 'of thickness 10micrometer were formed by heat-drying at 100 degreeC for 30 minutes. Thus, the thermally conductive member in which the silicone resin layers 22 and 22 'were formed in both surfaces of the sheet layer 21 which consists of thermally conductive sheets was obtained.

(Example 4)

In the thermally conductive member of Example 1, a thermally conductive member was produced in the same manner as in Example 1 except that the silicone resin layer 22 had antistatic properties. In addition, as the material for forming the silicone resin layer 22, 2 wt% of the conductive carbon black (manufactured by Mitsubishi Chemical Corporation, Diamond Black # 3150, average particle diameter of 26 mμ (= nm)) was added as a conductive agent. Silicone resin coating material (SR2316 by Toray Dow Silicone Co., Ltd.) was used.

(Example 5)

A thermally conductive member was fabricated in the same manner as in Example 1 except that a silicone resin coating material, which is a material for forming the silicone resin layer 22, was used in place of the fluorine resin coating material (manufactured by Toyo Rubber Co., Ltd., FN coating agent). did.

(Example 6)

In the thermally conductive member of Example 2, a thermally conductive member was produced in the same manner as in Example 2 except that the silicone resin, which is the material for forming the silicone resin layer 22, was used instead of the fluorine resin.

(Example 7)

A thermally conductive member was produced in the same manner as in Example 3 except that the silicone-based resin, which is a material for forming the silicone resin layers 22 and 22 ', was used in place of the fluorine resin in the thermally conductive member of Example 3.

(Example 8)

A thermally conductive member was produced in the same manner as in Example 4 except that the silicone-based resin, which is a material for forming the silicone-based resin layer 22, was used in place of the fluorine-based resin in the thermally conductive member of Example 4.

(Comparative Example 1)

A thermally conductive member was produced in the same manner as in Example 1 except that the silicone resin layer 22 was not formed from the thermally conductive member of Example 1. That is, only the thermally conductive sheet (containing the conductive agent) was used as the thermally conductive member.

(Comparative Example 2)

In the thermally conductive member of Example 1, a thermally conductive member was produced in the same manner as in Example 1 except that the sheet layer 21 did not have antistatic properties. That is, it was set as the heat conductive member that neither the sheet layer 21 nor the silicone resin layer 22 has antistatic property.

(Comparative Example 3)

In the thermal conductive member of Example 1, the sheet layer 21 was prevented from having antistatic properties, and the same as in Example 1 except that a silicone resin was used instead of the fluorine resin as a material for forming the silicone resin layer 22. To produce a thermally conductive member.

That is, the both of the sheet layer 21 and the fluorine-type resin layer (release layer) 22 did not have antistatic property as the heat conductive member.

Thus, as shown below, the surface resistance and workability were measured and evaluated for the thermally conductive members of the obtained examples and the comparative examples. The result was shown to the following Table 1-Table 3.

(Surface resistance)

It measured based on JISK6911. That is, surface resistance was measured by providing two electrodes on the layer surface which has antistatic property of a thermally conductive member, and applying the DC voltage 500V between electrodes and using the insulation resistance meter prescribed | regulated to JIS C 1302.

〔Workability〕

The thermal conductive member was repeatedly used 10 times to manufacture an article (liquid crystal display device) having an IC circuit. In addition, evaluation criteria were set as follows.

(Circle): A liquid crystal panel could shift and it could manufacture in a favorable state without a spark.

(Triangle | delta): A liquid crystal panel shift | deviated or the spark generate | occur | produced, and manufacture was not able to be performed in a favorable state.

Example One 2 3 4 Sheet layer Antistatic No antistatic property No antistatic property Antistatic Release layer * 1 One side formation One side formation Double sided formation One side formation No antistatic property Antistatic Antistatic Antistatic Surface resistance (Ω) 10 ⁸ 10 ⁷ 10 ⁷ (both cats) 10 ⁸ * 210 ⁷ * 3 Workability ○ ○ ○ ○

* 1: One side formation means that a release layer is formed in one side of a sheet layer, and double side formation means that a release layer is formed in both surfaces of a sheet layer.

* 2: Surface resistance on the sheet layer side

* 3: Surface resistance on the release layer side

(* 1 to * 3 are the same in the table below)

Example 5 6 7 8 Sheet layer Antistatic No antistatic property No antistatic property Antistatic Release layer * 1 One side formation One side formation Double sided formation One side formation No antistatic property Antistatic Antistatic Antistatic Surface resistance (Ω) 10 ⁸ 10 ⁷ 10 ⁷ (both cats) 10 ⁸ * 210 ⁷ * 3 Workability ○ ○ ○ ○

Comparative example One 2 3 Sheet layer No antistatic property No antistatic property No antistatic property Release layer * 1 Not forming One side formation One side formation No antistatic property No antistatic property Surface resistance (Ω) 10 ¹³ ＜ 10 ¹³ ＜ 10 ¹³ ＜ Workability △ △ △

The results of the above Tables 1 to 3 show that the Examples have a layer having antistatic properties, so that the article having the IC circuit is manufactured in a good state. On the other hand, since the comparative example 1 product does not have a release layer and the layer which has antistatic property is not formed, and the comparative example 2 product and 3 product do not form the layer which has an antistatic property, all have the IC circuit. It can be seen that the production of the article could not be carried out in good condition.

As described above, in the thermally conductive member of the present invention, a release layer is formed on at least one surface of a sheet layer made of a thermally conductive sheet, and at least one of the sheet layer and the release layer has antistatic property. Therefore, static electricity is not generated by repeated use of the thermally conductive member, and there is no problem that the mounted liquid crystal panel or the like is displaced or a spark is generated and the IC is destroyed. In addition, in the case of the thermally conductive member of the present invention, in manufacturing an article having an IC circuit, two sheets of a thermally conductive rubber sheet and a release heat-resistant film can be used without requiring two sheets. Savings and downsizing can be realized. In addition, since a release layer such as a silicone-based resin layer or a fluororesin-based resin can directly contact the adherend, and the thermal conductive sheet does not directly contact the adherend, it is possible to perform heat compression on the adherend satisfactorily. Could.

Claims (5)

In the heat conductive member provided with the sheet layer which consists of a thermally conductive sheet, and the mold release layer formed in at least one surface of this sheet layer, At least one of the said sheet layer and a release layer has antistatic property, The heat conductive member characterized by the above-mentioned. The method of claim 1, The surface resistance of the layer which has antistatic property is set to 10 <^10> ohms or less, The heat conductive member characterized by the above-mentioned. The method according to claim 1 or 2, A release layer is a silicone resin layer, The heat conductive member characterized by the above-mentioned. The method according to claim 1 or 2, The mold release layer is a fluorine-type resin layer, The heat conductive member characterized by the above-mentioned. The method according to any one of claims 1 to 4, A thermally conductive member, which is used for producing an article having an IC circuit.