KR102155811B1 - The manufacturing method for heat radiation adhesive and heat radiation tape with excellent in-plane thermal conductivity comprising the same - Google Patents

Abstract

The present invention relates to a method of manufacturing a heat radiation adhesive and a heat radiation tape including the same, and more specifically, in a heat radiation tape applied to a TV, mobile device, etc., a heat radiation adhesive layer is formed on the upper and lower portions of a metal film substrate, A method of manufacturing a heat-dissipating adhesive to improve thermal conductivity in the horizontal direction by forming a heat-dissipating adhesive layer as a heat-dissipating adhesive with high thermal conductivity by a filler and a combination thereof, and configuring it on the upper and lower portions of a metal film substrate, and a heat-radiating tape comprising the same It is about.

Description

Manufacturing method of heat-dissipating adhesive and heat-dissipating tape containing the same {THE MANUFACTURING METHOD FOR HEAT RADIATION ADHESIVE AND HEAT RADIATION TAPE WITH EXCELLENT IN-PLANE THERMAL CONDUCTIVITY COMPRISING THE SAME}

The present invention relates to a method of manufacturing a heat-dissipating adhesive and a heat-dissipating tape including the same, and more specifically, in a heat-dissipating tape applied to mobile devices such as TVs or smartphones, constituting a heat-dissipating adhesive layer on the upper and lower portions of the metal film substrate, Including a method of manufacturing a heat-dissipating adhesive that improves thermal conductivity in the horizontal direction by forming a heat-dissipating adhesive layer as a heat-dissipating adhesive with high thermal conductivity by an optimized heat-radiating filler and a combination thereof, and configuring it on the upper and lower portions of a metal film substrate. It relates to a heat radiation tape.

In general, as displays applied to mobile devices such as TVs and smartphones are realized with a large area and high resolution, heat generated along with power consumption when operating the device hinders the use of the device and degrades its performance. The problem of heat generation according to the trend of short and high integration greatly affects the proper operation and performance of the device, so it will be very important to solve this problem.

For example, a display driver IC (DDI, Display Driver IC) is a semiconductor chip that controls pixels constituting a display to express a desired screen on the display, and the DDI attached to the dual flexible display is a chip on film (COF) for the display panel. It also plays a role of connecting the printed circuit board (PCB) and the glass. This COF increases in usage as the display becomes larger and heats up when a semiconductor chip such as DDI mounted on the COF drives the display panel. Will occur.

Moreover, as the resolution of the display gradually increases, the heat generation becomes more severe. Therefore, it is necessary to solve the heat generation problem for the productivity of the display or the performance of the processor.

To this end, conventionally, the heat dissipation effect was increased by molding the heating element with a heat dissipating resin, but the resulting heat dissipation effect did not meet expectations, and damage to the semiconductor chip due to the difference in the coefficient of expansion of the heterogeneous material, and increase in production volume. Therefore, it was not widely used due to the burden of the expansion of heat-dissipating resin coating equipment.

Korean Patent Registration No. 1558418 "Conductive adhesive tape with heat dissipation function and its manufacturing method" (2015.10.01) Korean Patent Registration No. 1361105 "The heat dissipation tape with excellent thermal conductivity" (2014.02.04)

The present invention is to solve the above problems, in order to implement an optimal heat dissipation structure, a heat dissipation adhesive layer is laminated on the upper and lower portions of a metal film, and a heat dissipation filler optimized for the heat dissipation adhesive layer and a combination thereof are applied. An object of the present invention is to provide a method of manufacturing a heat-dissipating adhesive to maximize the heat-generating performance of the metal film by efficiently transferring and dissipating heat generated from a heat source to a metal film by imparting thermal conductivity, and a heat-dissipating tape including the same.

In order to achieve the above object, a method of manufacturing a heat-dissipating adhesive according to a preferred embodiment of the present invention includes the steps of adding a heat-radiating filler to a silicone-based adhesive resin or an acrylic adhesive resin; Stirring at 1,500 to 1,800 rpm for 15 to 20 minutes to disperse and mix a heat dissipating filler in the adhesive resin to obtain an adhesive mixture; And adding a curing agent and a catalyst to the adhesive mixture to obtain a pressure-sensitive adhesive, wherein the heat-dissipating filler is selected from inorganic ceramic-based heat-radiating fillers or carbon-based heat-radiating fillers.

Here, the silicone-based adhesive resin is made of polydimethylsiloxane as a main component, and a platinum catalyst or a curing catalyst made of benzoyl peroxide is used.

The acrylic adhesive resin is an acrylic acid ester copolymer, 2-ethylhexyl acrylate, butyl acrylate, vinyl acetate, acrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, Two or more types of monomers selected from maleic acid, 2-hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxypropyl acrylate are mixed and used.

In addition, the inorganic ceramic-based heat dissipating filler is used alone or in combination among alumina, boron nitride, aluminum nitride, magnesium oxide, zinc oxide, and silica.

In addition, the carbon-based heat dissipation filler is used alone or in combination among natural graphite, artificial graphite, graphene, carbon nanotubes, and silicon carbide.

In addition, the heat radiation tape including the heat radiation adhesive manufactured by the above method, in the heat radiation tape attached to a semiconductor chip, the substrate layer made of a metal film; An insulating layer made of a polymer film and disposed on the base layer for internal combustion and insulation; An upper heat dissipation adhesive layer disposed under the insulating layer and applied on the base layer and preventing thermal condensation due to the insulating layer; A lower heat dissipation adhesive layer applied under the base layer and vertically transferring heat generated from the semiconductor chip toward the base layer; And a liner layer detachably coupled to the lower heat dissipation adhesive layer.

Here, the metal film is selected from aluminum foil, copper foil, graphene or graphite-coated aluminum foil, graphene or graphite-coated copper foil.

The insulating layer is selected from polyester, polyimide, polyethylene naphthalate, polyether ether ketone, polytetrafluoroethylene, polybutylene terephthalate, polyamide, polyetherimide, polyethersulfone, and polyamideimide.

As described above, according to the method of manufacturing a heat dissipating adhesive of the present invention and a heat dissipating tape including the same, a metal film substrate is used to increase heat dissipation in the horizontal direction, but a silicon-based or acrylic pressure-sensitive adhesive (PSA) is used as a main component. It is formed in a structure in which a heat-dissipating adhesive is laminated on the upper and lower portions of a metal film substrate, and a heat-dissipating filler optimized for the heat-dissipating adhesive is applied to quickly transfer heat to the metal film substrate and provide an additional heat radiation effect to increase horizontal thermal conductivity. It has the advantage of improving the performance and extending the life of mobile devices such as TVs and smartphones.

1 is a cross-sectional configuration diagram of a heat radiation tape according to the present invention

Hereinafter, a preferred embodiment of the present invention will be described in detail so that those skilled in the art can easily implement the technical idea of the present invention. However, the present invention may be implemented in various different forms, and is not limited to the embodiments described herein.

1 is a cross-sectional configuration diagram of a heat dissipating tape having excellent horizontal thermal conductivity according to the present invention. In the drawing, "lower part" indicates a direction in contact with the semiconductor chip.

The present invention relates to a heat dissipation tape that allows effective heat dissipation by spreading heat horizontally in a substrate layer made of a metal film when transferring heat vertically from a heating element used as a heat source by being directly attached to a semiconductor chip. By applying a filler and a combination thereof, a heat-dissipating adhesive with high thermal conductivity is manufactured, thereby maximizing the heat dissipation performance of the metal film.

According to the drawings, the heat dissipating tape of the present invention comprises a base layer 10; An insulating layer 20; And a liner layer 30; comprising a heat dissipation adhesive layer 40 and 50 on the upper and lower portions of the metal film forming the base layer 10, respectively, so that the heat generated from the heat source is efficiently transferred to the metal film. It is characterized in that the delivery, release.

This will be described in more detail.

[1] structure of heat dissipation tape

As described above, the base layer 10 is made of a metal film and has excellent heat dissipation in the horizontal direction.

The metal film is preferably selected from among aluminum foil, copper foil, graphene or graphite coated aluminum foil, graphene or graphite coated copper foil.

At this time, if the metal film is too thin, the heat dissipation performance deteriorates, whereas if the metal film is too thick, the heat dissipation tape of the present invention is attached to an adherend such as a semiconductor chip and is then bent if necessary, due to the rigidity of the metal film itself. Since there is a risk of delamination, it is preferable to be formed in a thickness of 12 ~ 80㎛.

The insulating layer 20 is made of a polymer film and is disposed on the top of the base layer, that is, the outermost layer of the heat dissipating tape constituting the present invention for heat resistance and insulation.

The polymer film is polyester (PET, Polyethylene Terephthalate), polyimide (PI, Poly Imide), polyethylene naphthalate (PEN, Polyethylene Naphthalate), polyetherether ketone (PEEK), polytetrafluoroethylene (PTFE). , Poly Tetra Fluoro Ethylene), Polybutylene terephthalate (PBT), Polyamide (PA, Polyamide), Poly Ether Imide (PEI), Polyethersulfone (PES), Polyamideimide (PAI, Poly Amide Imide) is selectively used.

At this time, if the thickness of the insulating layer is too thin, the insulating property deteriorates, whereas if the thickness exceeds a certain thickness, the vertical heat dissipation effect decreases, and as with the metal film, there is a concern that peeling (falling off) may occur during bending due to its own resilience. Therefore, it is preferably formed to a thickness of 12 to 50㎛.

The upper heat dissipation adhesive layer 40 is formed of a heat dissipation adhesive and is disposed under the insulating layer for bonding with a metal film as a base layer. That is, the upper heat dissipation adhesive layer 40 is applied on the top of the base layer to prevent heat condensation due to the insulating layer for heat resistance and insulation, thereby implementing more effective heat dissipation performance.

The lower heat dissipation adhesive layer 50 is formed by being applied to the lower part of the substrate layer, and is directly attached to the semiconductor chip to perform a heat dissipation function. Due to the excellent vertical heat transfer effect of the lower heat dissipation adhesive layer, heat is transferred to the metal film as the base layer. It reaches quickly and functions to maximize the horizontal heat dissipation effect of the metal film.

The release liner layer 30 is detachably coupled to the lowermost portion of the heat dissipating tape having the above structure.

[2] Composition of heat dissipation adhesive layer

Next, the upper and lower heat dissipation adhesive layers 40 and 50, which are the most characteristic components of the present invention, will be described in more detail.

The upper and lower heat dissipation adhesive layers 40 and 50 are made of a silicone-based pressure sensitive adhesive (Silicone PSA, pressure sensitive adhesive) or an acrylic pressure sensitive adhesive (Acrylic PSA), that is, a silicone-based resin or an acrylic resin as the main component, and here It is made by adding a heat-dissipating filler.

The silicone-based pressure-sensitive adhesive is made of polydimethylsiloxane (PDMS) as a main raw material, and a curing catalyst such as a platinum (Pt) catalyst or benzoyl peroxide is used.

The acrylic pressure-sensitive adhesive is an acrylic ester-based copolymer, 2-ethylhexyl acrylate (2-Ethylhexyl acrylate), butyl acrylate (Butyl acrylate), vinyl acetate (Vinyl acetate), acrylic acid (Acrylic acid), methyl methacrylate (Methyl methacrylate), ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, maleic acid, 2-hydroxypropyl methacrylate Acrylate (2-hydroxypropyl methacrylate), 2-hydroxyethyl methacrylate (2-Hydroxyethyl methacrylate), 2-hydroxyethyl acrylate (2-Hydroxyethyl acrylate), 2-hydroxypropyl acrylate (2-Hydroxypropyl acrylate) ) And the like are used by mixing two or more kinds of monomers.

In addition, aziridine, isocyanate, epoxy, and metallic chelate compounds are used as curing agents. When using an isocyanate-based curing agent, a tin catalyst is used to control the reaction rate. It is also used.

In addition, in order to obtain excellent thermal conductivity by imparting a heat dissipation effect to a silicone or acrylic resin, the application of a heat dissipation filler applied to the heat dissipation adhesive layer is very important. In the present invention, the inorganic ceramic heat dissipation filler or A carbon-based heat dissipating filler of 1-15㎛ is used.

That is, if the size of the heat dissipation filler exceeds 20 μm, it may occur that the heat dissipation filler protrudes to the adhesive surface, so do not exceed this size, but most preferably, a size of about 1 to 10 μm is applied. .

Inorganic ceramic-based heat dissipating fillers include alumina (Alumina, Al ₂ O ₃ ), boron nitride (BN, Boron Nitride), aluminum nitride (AlN, Aluminum Nitride), magnesium oxide (MgO, Magnesium Oxide), and zinc oxide (ZnO, Zinc Oxide). ), silica (SiO ₂ ), and the like.

The carbon-based heat dissipation filler is selectively selected from fillers such as natural graphite, artificial graphite, graphene, carbon nanotubes (CNTs), and silicon carbides. It is used and has higher thermal conductivity than inorganic ceramic-based heat dissipating fillers.

The carbon-based heat dissipation filler is most representatively graphite, which is formed in a sheet form, and has a horizontal thermal conductivity of 600w/mk or more and a vertical thermal conductivity of 5w/mk or more. The degree is high and there is no significant difference between the two, but the thermal conductivity of artificial graphite is better than that of natural graphite.

The graphite is good for use as a heat dissipation material by adding it to the adhesive layer according to its shape, but when the graphite sheet is cut, dust may be generated, and the heat dissipation performance may be deteriorated due to the decrease in thermal conductivity due to the addition of the adhesive layer. The problem of lowering the thermal conductivity was improved by dispersing the powder in the adhesive.

In addition, when the upper and lower heat dissipation adhesive layers 40 and 50 to which the heat dissipation filler is applied are too thick, the heat insulation effect is generated due to the generation of bubbles in the adhesive layer when the heat dissipation tape including the adhesive layer is manufactured. On the other hand, if the thickness is too thin, it is difficult to see the effect when applying the heat dissipation filler in various sizes. Therefore, it is set around 20 to 50 µm, preferably 30 µm in consideration of the heat dissipation filler size and adhesion to the substrate layer. This is desirable.

[3] Method for producing heat-dissipating adhesive

Next, a method of manufacturing a heat-dissipating adhesive by adding a heat-dissipating filler to secure heat-radiating performance to the acrylic resin or silicone-based resin will be described.

⑴ Use of inorganic ceramic heat dissipation filler

It relates to a method of manufacturing a heat-dissipating pressure-sensitive adhesive by using an acrylic pressure-sensitive adhesive resin having excellent heat resistance as a base, and applying an inorganic ceramic-based heat-radiating filler such as alumina and boron nitride having a heat-radiating effect thereto.

A heat-dissipating filler is added to the acrylic adhesive resin and stirred at 1,500 to 1800 rpm for 15 to 20 minutes to disperse and mix the heat-dissipating filler in the resin. In this process, when frictional heat is generated by the heat dissipating filler, it is cooled at room temperature and selected from aziridine, isocyanate, epoxy, and metal chelate compounds as a curing agent, or an isocyanate curing agent is added to a tin catalyst to prepare a heat dissipating adhesive.

At this time, the heat dissipation filler is preferably different in size and filling rate according to the type of the acrylic adhesive resin mixed.

For example, alumina is the most universally used heat dissipation filler, and it is inexpensive and has a variety of particle sizes and shapes, but has a slightly low thermal conductivity of 20w/mk. Such alumina uses a size of 1-20㎛ and a filling rate of 50 ~70phr can be applied alone for each size, or a mixing ratio can be applied for each size.

Boron nitride (BN) has a high thermal conductivity of 120w/mk, and its utilization is increasing in recent years, but it is expensive and difficult to fill due to its high specific surface area, and such boron nitride (BN) uses a size of 1-10㎛. And, with a filling rate of 10 to 30 phr, it can be applied alone for each size or a mixing ratio for each size can be applied.

Aluminum nitride (AIN) has a high thermal conductivity of 180w/mk, but it is expensive and can be filled in a small amount due to hydrolysis problems.

Magnesium oxide (MgO) has a thermal conductivity of 40w/mk, and zinc oxide has a thermal conductivity of 45w/mk, and the price is slightly higher, so you can fill it in a small amount.

Silica is mainly used together with other heat dissipating fillers to prevent sedimentation of other heat dissipating fillers and fill the gap.

In this way, it may be selectively used alone or in combination in consideration of conditions such as thermal conductivity and price of the heat dissipating filler.

In addition, when mixing these heat dissipating fillers, for example, boron nitride: alumina: boron nitride, respectively, 6 μm: 3 μm: 1 μm in a ratio of 6 to 8: 3 to 1: 1 to make the heat transfer network more efficient. By forming, it is possible to obtain high thermal conductivity. In other words, the heat conduction efficiency can be improved when the heat dissipation filler is used in combination rather than alone, and when the heat dissipation filler is used in combination, it may be selectively used in consideration of the thermal conductivity of the heat dissipation filler itself and the price of the heat dissipation filler. .

In addition, although the above description illustrates that the main component is an acrylic resin, a silicone resin can also be obtained in the same manner.

This will be described in more detail through the following test examples.

⑵ Use of carbon-based heat dissipation filler for acrylic resin

It relates to a method of manufacturing a heat-dissipating pressure-sensitive adhesive by using an acrylic pressure-sensitive adhesive resin having excellent heat resistance as a main component and applying a carbon-based heat-radiating filler such as graphite having a heat-radiating effect thereto.

The method of mixing and dispersing the carbon-based heat-dissipating filler in the acrylic adhesive resin is the same as described in ⑴ above, and the heat-radiating filler, like the inorganic ceramic-based heat-radiating filler, varies the size and filling rate according to the type mixed with the acrylic adhesive resin. It is good.

For example, graphite may be used in a size of 1 to 15 μm and a filling rate of 10 to 30 phr may be applied individually for each size or a mixing ratio may be applied for each size.

In addition, inorganic ceramic-based heat dissipating fillers and carbon-based heat dissipating fillers can be mixed, i.e., graphite and boron nitride each 5㎛:1㎛ size are mixed in a ratio of 7~9:3~1 to obtain high thermal conductivity. You will be able to.

In addition, in the above test example, a method of mixing and using a heat dissipating filler with an acrylic adhesive resin was described, but when a heat dissipating filler is added to a silicone adhesive resin, it may be performed in the same manner as described above.

As described above, the base layer is made of a metal film to conduct heat diffusion in the horizontal direction, and the upper and lower heat dissipation adhesive layers are stacked on top and bottom, respectively, and optimized as obtained in [3] above. By applying the heat dissipation filler and the combination thereof to the adhesive layer, it is possible to impart an additional heat dissipation effect with rapid heat transfer.

[4] Test example

Next, the thermal conductivity performance of the heat dissipating tape according to the present invention will be described in detail through the following test examples. However, the following test examples are only examples to aid the understanding of the present invention, and the present invention is not limited thereto.

<Test Example 1>

This test example is to evaluate the thermal conductivity of the heat-dissipating tape according to the addition (content) of the inorganic ceramic-based heat-dissipating filler.Acrylic adhesive resin is used as the main raw material of the heat-dissipating adhesive, and alumina is used as the heat-radiating filler, but the thickness and filling rate are different. It was set as Test Sections 1 to 6, and a heat-dissipating tape to which a pressure-sensitive adhesive without a heat-radiating filler was applied was used as a control.

Here, the thickness of the upper and lower heat dissipating adhesives (pressure sensitive adhesive: PSA) was formed to be 30 μm, and accordingly, the thickness of the heat dissipating filler was 3 μm, 5 μm, and 10 μm, respectively.

Alumina, which is a heat dissipating filler, was added to the acrylic adhesive excluding the curing agent and the catalyst, and a solvent mix, followed by stirring at 1800 rpm for 15 to 20 minutes using a stirrer. In this process, as heat generation occurs due to friction between materials, it is prepared by sufficiently cooling at room temperature and adding a curing agent and a catalyst. The results of evaluating the vertical and horizontal thermal conductivity of the test groups and the control obtained therefrom are shown in Table 1 below.

Horsfield's packing model formula, which is a filler combination calculation formula, was applied to the combination of heat dissipation fillers having different sizes in this example, and the amount of addition according to the size of the heat dissipation filler is calculated by the initial volume ratio and then multiplied by the specific gravity of the filler, and converted into mass ratio when actually added. Was added, and an adhesive was prepared in the same manner as in Test Example 1.

According to the results of Table 1, test sections 5 and 6 having a high alumina thickness showed the highest thermal conductivity, while the surface of the lower heat dissipating adhesive layer was rough and somewhat non-glossy. Accordingly, due to the roughness of the surface of the lower heat dissipating adhesive layer, it is likely that there will be a decrease in actual heat generation performance due to a decrease in adhesion to the heat source. In addition, in the case of Test Sections 1 to 4, the thermal conductivity was lower than that of Test Sections 5 and 6, but it was found that the surface roughness of the lower heat dissipating adhesive layer was not present. On the other hand, there was no significant difference according to the filling rate of the heat dissipating filler.

In addition, the vertical thermal conductivity of the test sphere was slightly higher than that of the control, and in the case of the horizontal thermal conductivity, the test sphere appeared to be high due to a significant difference. As in the present invention, the heat dissipation tape having a multi-layer structure -When evaluating the vertical thermal conductivity through the lower or lower-upper part, the thermal conductivity of each layer is different and there is no significant difference between the test and control due to the thermal resistance of each layer, whereas the heat transfer effect of the upper and lower radiating adhesive layers Therefore, it was determined that it was effective in improving the horizontal thermal conductivity by rapidly transferring heat to the metal film, which is the base layer, and it was confirmed that the thermal conductivity was improved when the heat dissipating filler was used.

<Test Example 2>

This test example is to improve the thermal conductivity of the heat dissipating tape according to the present invention, and the heat dissipation filler having the same size (thickness) is used alone or a heat dissipating filler having a different size is used in combination. Evaluated.

Table 2 shows the mixing ratio of alumina, Table 3 shows the thermal conductivity according to the combination of the heat dissipating fillers for each size according to Table 2, and in this test example, the same control as Test Example 1 was used.

According to the results of Table 3, the overall thermal conductivity was higher than that of Test Example 1. This is because the heat transfer network is well formed because the gaps between the large particles of heat dissipation fillers fill the gaps between the large particles of heat dissipation fillers according to Horsfield's packing model. As a result, it is judged that it showed better thermal conductivity than the heat dissipation filler of the same size.

However, in the case of test section 7 to which alumina 10㎛ was added, the thermal conductivity was the highest, but as in test sections 5 and 6 to which alumina 10㎛ was applied in Test Example 1, the surface of the lower heat dissipation adhesive layer was rough when applied to the heat dissipation tape. A decrease in heat dissipation performance was expected. Accordingly, in test section 9, the mixing ratio of alumina 10㎛ and alumina 5㎛ was changed, but surface irregularities occurred due to the influence of alumina 10㎛ and thermal conductivity was also decreased compared to test section 7, and the surface condition and thermal conductivity of the lower heat dissipation adhesive layer Considering the degree, it is judged that the best results can be obtained when test section 8 is applied.

As described above, according to the results of Test Examples 1 and 2, it was found that applying a combination of heat dissipation fillers of different sizes is more effective at the same heat dissipation filler filling rate, rather than applying a heat dissipation filler of a certain size alone, which will be described later. In Test Example 3, it was confirmed that even when boron nitride was applied instead of alumina, thermal conductivity was high when heat-radiating fillers of different sizes were combined.

<Test Example 3>

In this test example, a heat-dissipating adhesive was prepared in the same manner as in Test Example 1, but as a heat-dissipating filler, 1 µm and 6 µm plate-shaped boron nitride were used instead of spherical alumina. At this time, the filling rate of the heat dissipation filler is determined by the specific surface area among the characteristics of the heat dissipation filler, and the specific surface area of alumina is 0.2 to 0.4 ㎡/g and boron nitride is 10 to 25 ㎡/g. The smaller the specific surface area, the greater the amount of heat dissipating filler can be filled in the pressure-sensitive adhesive, and thus the filling rate of boron nitride having a larger specific surface area than alumina is inevitably lower.

The filling rate of boron nitride exceeded 30phr as a result of applying 10, 20, and 30phr, so it was difficult to increase the viscosity and effectively disperse when added. This resulted in a decrease in coating properties, so that the boron nitride filling rate was 30 phr, and upper and lower heat-dissipating adhesives were prepared according to the ratios in Table 4 below.

According to this test example, unlike when alumina was applied, the problem of surface roughness of the adhesive layer did not occur, and the initial adhesive strength was also excellent, so it was expected that there would be no problem in adhesion to the heat source. In addition, in order to check the reproducibility of the effect according to the combination of the radiating filler size, a sample obtained by mixing the radiating filler alone and by size was tested, and at this time, the tendency of the thermal conductivity was grasped in this test example through the adjustment of the mixing ratio, and the results are shown in the table. It is shown in 5.

According to the results of Table 5, in the case of horizontal thermal conductivity, test section 14 was the highest.This is because the mixing between the plate-shaped heat-radiating fillers also uses a large-sized heat-dissipating filler and a small-sized heat-radiating filler at a certain ratio as in the spherical form. It is judged that it is advantageous to obtain high thermal conductivity when mixing, and the thermal conductivity is higher than that of Test Sections 1 and 2 in which alumina was used as a heat dissipating filler.

<Test Example 4>

In this Test Example, a heat-dissipating adhesive was prepared in the same manner as in Test Example 1, but in order to fill the gap between the heat-dissipating fillers in order to increase the efficiency of the heat transfer network of boron nitride having good thermal conductivity as a heat-dissipating filler, alumina and The thermal conductivity was measured by mixing and applying, and the results are shown in Table 7. At this time, the filling rate of the heat dissipation filler was set to 30 phr.

According to Table 7 above, it was found to have high thermal conductivity overall, and this is because spherical alumina well fills the gap that cannot but arise even through combination with other sizes due to the structure of the plate-shaped boron nitride, thereby forming an excellent heat transfer network. I could see that it was. However, in the case of test section 18, which constitutes a heat transfer network by mixing alumina as a main component and boron nitride as a heat dissipating filler, it exhibits lower thermal conductivity compared to the test sections containing boron nitride as the main component, which is itself in the case of alumina. This is because the thermal conductivity of is lower than that of boron nitride, and when boron nitride in a plate shape is added to the heat transfer network formed by spherical alumina, the function of supplementing the heat transfer network is degraded.

<Test Example 5>

In this test example, the thermal conductivity was measured using a carbon-based heat-radiating filler, and graphite 3,5 μm was used as a carbon-based heat-radiating filler, and a heat-dissipating adhesive was prepared in the same manner as in Test Example 1. In addition, the specific surface area of graphite was 26㎡/g, similar to that of boron nitride, and accordingly, the test was performed by applying a filling rate of 30%. The graphite mixing ratio is shown in Table 8 below, and the thermal conductivity measured in this test is shown in Table 9.

According to Table 9, test sections 18 and 19 in which graphite was applied alone by size showed approximately similar horizontal thermal conductivity, and test sections 20 through 22 applied in combination by size were higher than those applied alone, but the difference according to the mixing ratio was It turned out not to be big. This is considered to be because there is no significant difference between the graphite size of 3 μm and 5 μm.

In addition, it exhibited higher thermal conductivity than the heat-radiating adhesives obtained in Test Examples 1 to 4 in which the inorganic ceramic-based heat-radiating filler was used.

<Test Example 6>

In this test example, a heat-dissipating adhesive was prepared in the same manner as in Test Example 1, but boron nitride was mixed with graphite having good thermal conductivity as a heat-dissipating filler, and the specific surface area of graphite and boron nitride was similar to 20-26㎡/g. It has a filling rate of 30%. At this time, the mixing ratio of the heat dissipating filler was 7:3, which is judged to have the best mixing result between sizes, as shown in Table 10 below, and the thermal conductivity is shown in Table 11.

According to Table 11, the test section 23 containing graphite as a main component showed higher thermal conductivity than the test section 24 containing boron nitride as the main component, which has a lower thermal conductivity than graphite. It was confirmed that the heat transfer network was efficiently formed by adequately filling the gap due to the difference in size of boron nitride.

As described above, in the case of the heat dissipation tape having the structure as shown in Fig. 1, the heat transfer network is formed by filling the gaps between the heat dissipating fillers that occur when a heat dissipating filler having high thermal conductivity is dispersed in the adhesive to obtain high horizontal thermal conductivity. It was confirmed that it is very important to perform efficiently.

10: base layer 20: insulating layer
30: liner layer 40: upper heat dissipation adhesive layer
50: lower heat dissipation adhesive layer

Claims (9)

Adding a heat dissipating filler to the silicone adhesive resin or the acrylic adhesive resin;
Including; stirring at 1,500 to 1,800 rpm for 15 to 20 minutes, dispersing and mixing a heat dissipating filler selected from inorganic ceramic based heat dissipating fillers or carbon based heat dissipating fillers in the adhesive resin and then cooling at room temperature; Including,
Further comprising a; step of further adding a curing agent and a catalyst when the pressure-sensitive adhesive resin is acrylic,
The inorganic ceramic-based heat dissipation filler is used alone or in combination among alumina, boron nitride, aluminum nitride, magnesium oxide, zinc oxide, and silica having a size of 1 to 20 μm,
The carbon-based heat-dissipating filler is a method of producing a heat-dissipating adhesive, characterized in that used alone or in combination among natural graphite, artificial graphite, graphene, carbon nanotubes, and silicon carbide having a size of 1 to 15 μm. The method of claim 1,
The silicon-based adhesive resin is a method for producing a heat dissipating adhesive, characterized in that the polydimethylsiloxane as a main raw material and a platinum catalyst or a curing catalyst made of benzoyl peroxide is used. The method of claim 1,
The acrylic adhesive resin is an acrylic acid ester-based copolymer, 2-ethylhexyl acrylate, butyl acrylate, vinyl acetate, acrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, Characterized in that it is used by mixing two or more monomers selected from maleic acid, 2-hydroxypropyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxypropyl acrylate. Method for producing a heat-dissipating adhesive. delete delete In the heat dissipation tape attached to a semiconductor chip,
A base layer 10 made of a metal film and having a thickness of 12 to 80 μm;
An insulating layer 20 disposed on the base layer for heat resistance and insulation, made of a polymer film, and having a thickness of 12-50 μm;
An upper heat dissipation adhesive layer 40 disposed under the insulating layer to prevent thermal condensation due to the insulating layer and applied on the top of the base layer and having a thickness of 20 to 50 μm;
A lower heat dissipation adhesive layer 50 having a thickness of 20 to 50 μm and applied under the base layer so as to vertically transmit heat generated from the semiconductor chip toward the base layer; And
Includes; a liner layer 30 detachably coupled to the lower heat dissipation adhesive layer,
The heat dissipation tape, characterized in that the upper and lower heat dissipation adhesive layers (40, 50) are formed of a heat dissipation adhesive prepared according to any one of claims 1 to 3. delete delete delete

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