Silicone based resin composition, and semiconductor device comprising the same
The silicone-based resin composition with agglomerated primary particles addresses thermal conductivity deviations and coverage issues, ensuring reliable and efficient heat dissipation in semiconductor devices by maintaining consistent thermal performance across varying conditions.
Patent Information
- Application Number
- PCT/EP2024/054956
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-27
- Publication Date
- 2025-09-04
AI Technical Summary
Existing silicone-based resin compositions for heat dissipation in semiconductor devices suffer from thermal conductivity deviations and reduced coverage due to the use of conventional conductive fillers, leading to inadequate heat dissipation properties and reliability issues.
A silicone-based resin composition incorporating agglomerated primary particles as a first conductive filler, with a specific surface area to average particle diameter ratio of 0.3 < A(m2/g)/B(μm) < 3.0, combined with organic polysiloxane and a curing catalyst, enhances thermal conductivity and coverage, ensuring consistent performance under varying pressurization conditions.
The composition achieves improved thermal conductivity, uniform coverage, and enhanced adhesive strength, minimizing thermal conductivity deviations and maintaining reliability even under different manufacturing pressures, thus optimizing heat dissipation in semiconductor devices.
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Figure EP2024054956_04092025_PF_FP_ABST
Abstract
Description
[0001] SILICONE BASED RESIN COMPOSITION, AND SEMICONDUCTOR DEVICE
[0002] COMPRISING THE SAME
[0003] [Technical Field]
[0004] The present invention relates to a silicone-based resin composition and a semiconductor device including the same.
[0005] [Background Art]
[0006] Since most electronic components generate heat during use thereof, it is necessary to remove heat from the electronic components in order for them to function properly. In particular, the amount of heat generated by integrated circuit elements such as CPUs used in personal computers is increasing due to faster operating frequencies, and heat countermeasures have become an important issue.
[0007] Accordingly, many methods for dissipating heat have been proposed, and, for electronic components that dissipate a lot of heat, a method of dissipating heat by interposing a thermally conductive material, such as a thermally conductive grease or a thermally conductive sheet, between electronic components and members such as a heat sink has been proposed.
[0008] Korean Patent Application Publication No. 10-2020-0086307 discloses a semiconductor device including a thermally conductive material.
[0009] [Related Art Document]
[0010] [Patent Document]
[0011] (Patent Document 1) Korean Patent Application Publication No. 10-2020-0086307
[0012] [Disclosure]
[0013] [Technical Problem]
[0014] Therefore, the present invention has been made in view of the above problems, and it is one object of the present invention to provide a silicone-based resin composition capable of minimizing a thermal conductivity deviation and providing excellent heat dissipation properties due to improved coverage; and a semiconductor device including the silicone-based resin composition.
[0015] [Technical Solution]
[0016] In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a silicone-based resin composition, including: an organic polysiloxane; a first conductive filler; and a curing catalyst, wherein the first conductive filler includes secondary particles in which primary particles are agglomerated, wherein the first conductive filler satisfies Equation 1 below:
[0017] [Equation 1]
[0018] 0.3 < A(m2 / g) / B( ni) < 3.0 where A represents a specific surface area of the first conductive filler and is a value excluding a unit, and B represents an average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
[0019] In an embodiment of the present invention, the primary particles may be flaky particles.
[0020] In an embodiment of the present invention, the first conductive filler may have an aspect ratio of 0.5 to 3.
[0021] In an embodiment of the present invention, the first conductive filler may have a tapped density of 0.5 g / cm3to 6 g / cm3.
[0022] In an embodiment of the present invention, the silicone-based resin composition may further include a spherical second conductive filler different from the first conductive filler.
[0023] In an embodiment of the present invention, the second conductive filler may have an aspect ratio of 1 to 1.5.
[0024] In an embodiment of the present invention, a weight ratio of the first conductive filler :the second conductive filler may be 1 : 1 to 1 :5.
[0025] In an embodiment of the present invention, a lap shear strength of the silicone-based resin composition measured by DIN EN 1465 may be 1 N / mm2or more.
[0026] In an embodiment of the present invention, a coverage, measured by Measurement Method 1 below, of the silicone-based resin composition may be 90 % or more:
[0027] [Measurement Method 2]
[0028] 1) the silicone-based resin composition is coated in a weight of 0.7 g on a first silicone substrate having a size of 27 mm *27 mm,
[0029] 2) a second silicone substrate, which has a size the same as or larger than the first silicone substrate, is placed on the coated silicone-based resin composition, and then the silicone- based resin composition is cured in a state of being compressed with a force of 3 kgf,
[0030] 3) an area where the first silicone substrate is in close contact with the second silicone substrate by the cured silicone-based resin composition is derived, and
[0031] 4) the coverage is a ratio of an area of the first silicon substrate in close contact with the second silicon substrate compared to a planar area of the first silicon substrate.
[0032] In an embodiment of the present invention, a thermal conductivity change rate of the silicone-based resin composition measured by Measurement Method 2 below may be less than 30 %:
[0033] [Measurement Method 2]
[0034] 1) the silicone-based resin composition is molded by heat press for 15 minutes under conditions of 165°C and a pressure of 10 kgf / cm2to manufacture a first sheet, and separately, the silicone-based resin composition is molded by heat press for 15 minutes under conditions of 165°C and a pressure of 0.1 kgf / cm2to manufacture a second sheet,
[0035] 2) the first sheet and the second sheet are cured at 150°C for 2 hours to respectively manufacture a sample of the first sheet and a sample of the second sheet,
[0036] 3) a thermal conductivity of the first sheet sample and a thermal conductivity of the second sheet sample are measured at 25°C according to ISO 22007-2,
[0037] 4) a thermal conductivity change rate is calculated according to Equation 2 below:
[0038] [Equation 2]
[0039] Thermal conductivity change rate(%) = ( | TCio - TCo.i | / TCio)x100 where TCio is a thermal conductivity (W / mK) of the first sheet sample, and TCo.i is a thermal conductivity (W / mK) of the second sheet sample.
[0040] In accordance with another aspect of the present invention, there is provided a semiconductor device, including: a semiconductor package; a heat dissipation part disposed on the semiconductor package; and a heat conduction layer interposed between the semiconductor package and the heat dissipation part, wherein the heat conductive layer includes a silicone- based resin composition, wherein the silicone-based resin composition includes an organic polysiloxane, a first conductive filler, and a curing catalyst, wherein the first conductive filler includes secondary particles in which primary particles are agglomerated, and the first conductive filler satisfies Equation 1 below:
[0041] [Equation 1]
[0042] 0.3 < A(m2 / g) / B( ni) < 3.0 where A represents a specific surface area of the first conductive filler and is a value excluding a unit, and B represents an average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
[0043] [Advantageous effects]
[0044] The silicone-based resin composition according to the present invention includes granular secondary particles, in which primary particles are agglomerated, as a first conductive filler, and a ratio of the specific surface area to the average particle diameter of the first conductive filler is greater than 0.3 and less than 3.0.
[0045] Accordingly, the first conductive filler included in the silicone-based resin composition can exhibit excellent thermal conductivity due to the large average particle diameter and large specific surface area.
[0046] In addition, the silicone-based resin composition exhibits a thermal conductivity value allowing the performance of appropriate heat dissipation function even when manufactured for commercialization under different pressurizing conditions, and the reliability of product performance may be improved due to a small thermal conductivity deviation of the silicone- based resin composition.
[0047] A cured product of the silicone-based resin composition according to the present invention can implement high thermal conductivity and, at the same time, can have improved coverage and an appropriate spread thickness. Therefore, when the silicone-based resin composition is used for a semiconductor device, the silicone-based resin composition can be coated to a uniform thickness between a semiconductor package and a heat dissipation part, so that the heat dissipation function can be improved.
[0048] [Description of Drawings]
[0049] FIG. 1 is a sectional view illustrating a process of measuring the lap shear strength and Junction separation length of a silicone-based resin composition.
[0050] FIG. 2 is a sectional view illustrating a cross section of a semiconductor device according to an embodiment.
[0051] [Best Mode]
[0052] Structural or functional descriptions of embodiments disclosed in the present specification or application are merely illustrated for the purpose of explaining embodiments according to the technical idea of the present invention, embodiments according to the technical idea of the present invention may be implemented in various forms other than the embodiments disclosed in the present specification or application, and it is not to be construed that the technical idea of the present invention is limited to the embodiments described in the present specification or application..
[0053] In the present specification or application, when a certain part “includes” a certain component, this indicates that the part may further include another component instead of excluding another component unless there is no different disclosure. In addition, it should be understood that all numerical ranges representing physical property values, dimensions, etc. of components described in the present specification or application are modified by the term 'about' in all cases unless otherwise specified.
[0054] In the present specification or application, it will be understood that when each part, surface, layer or substrate is referred to as being “on” or “under” another part, surface, layer or substrate, the part, surface, layer or substrate can be directly on another part, surface, layer or substrate or intervening part, surface, layer or substrate, and criteria for “on” and “under” will be provided based on the drawings. Elements in the following drawings may be exaggerated, omitted, or schematically illustrated for conveniences and clarity of explanation, and the sizes of elements do not reflect their actual sizes completely.
[0055] Now, a silicone-based resin composition according to the present invention and a semiconductor device including the same are described.
[0056] The silicone-based resin composition according to the present invention includes organic polysiloxane.
[0057] The organic poly siloxane may be represented by Formula 1 below:
[0058] [Formula 1]
[0059] RJaSiOb
[0060] In Formula 1, R1may represent one or two or more groups selected from a group consisting of a hydrogen atom, a hydroxy group and a saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms, and a may be about 1.8 to about 2.2. a+b may be about 3.5 to about 8. a+b may be 4.
[0061] In Formula 1, the saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms represented by R1may be, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, a hexyl group, an octyl group, a decyl group, a dodecyl group, a tetradecyl group, a hexadecyl group or an octadecyl group; a cycloalkyl group such as a cyclopentyl group or a cyclohexyl group; an alkenyl group such as a vinyl group or an allyl group; an aryl group such as a phenyl group or a tolyl group; an aralkyl group such as a 2- phenylethyl group or a 2-methyl-2-phenylethyl group; or a halogenated hydrocarbon group such as a 3,3,3-trifluoropropyl group, a 2-(perfluorobutyl)ethyl group, a 2-(perfluorooctyl)ethyl group or a p-chlorophenyl group.
[0062] The organic polysiloxane may have a weight average molecular weight of about 40,000 g / mol to about 80,000 g / mol, about 30,000 g / mol to about 100,000 g / mol, about 500 g / mol to about 10,000 g / mol, about 700 g / mol to about 7,000 g / mol, about 1,000 g / mol to about 5,000 g / mol, or about 1,500 g / mol to about 3,000 g / mol. The weight average molecular weight may be measured based on polystyrene.
[0063] A kinematic viscosity at 25°C of the organic polysiloxane may be 10 mm2 / s to 100,000 mm2 / s, 20,000 mm2 / s to 100,000 mm2 / s, or about 30 mm2 / s to about 10,000 mm2 / s. The kinematic viscosity of the organic polysiloxane may be measured at 25°C with an Ostwald viscometer.
[0064] Since the organic polysiloxane has a weight average molecular weight and kinematic viscosity in the ranges, it may maintain appropriate adhesive force to an adherend and improve durability by preventing voids and cracks from thermal shock.
[0065] The organic polysiloxane may include a first organic polysiloxane.
[0066] The first organic polysiloxane includes an alkenyl group bonded to a silicon atom. At least 2, 2 to 10, 2 to 5 or 2 alkenyl groups may be present in one molecule of the first organic polysiloxane.
[0067] The first organic poly siloxane may be represented by Formula 2 below:
[0068] [Formula 2]
[0069] RJaR^SiOb
[0070] In Formula 2, R1may be the hydrogen atom, the hydroxyl group or the saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms, and R2may be the alkenyl group. In Formula 2, a+c may be about 1.8 to about 2.2, and a+b+c may be about 3.5 to about 8. In Formula 2, a+b+c may be about 4. In Formula 2, and a may be about 1.8 to about 2.2. In addition, c may be 0.0001 to 0.1.
[0071] The first organic poly siloxane may be represented by Formula 3 below:
[0072] [Formula 3]
[0073] In Formula 3, R1may be the hydrogen atom, the hydroxyl group or the saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms, and R2may be the alkenyl group. In addition, in Formula 3, n may be 1 to 1,500, and m may be 0 to 20. In Formula 3, n may be 10 to 1,000, and m may be 0 to 20.
[0074] The first organic poly siloxane may be represented by Formula 4 below:
[0075] [Formula 4]
[0076] In Formula 4, n may be 1 to 1,500. n may be 10 to 1,000.
[0077] The first organic polysiloxane may have a weight average molecular weight (Mw) of about 500 g / mol to about 10,000 g / mol, about 700 g / mol to about 7,000 g / mol, about 1,000 g / mol to about 5,000 g / mol, or about 1,500 g / mol to about 3,000 g / mol. The weight average molecular weight may be measured based on polystyrene.
[0078] A kinematic viscosity at 23°C of the first organic polysiloxane may be 10 cPs to 100,000 cPs, 30 cPs to 50,000 cPs, or 10,000 cPs to 40,000 cPs. The kinematic viscosity of the first organic polysiloxane may be measured at 23°C with an Ostwald viscometer.
[0079] The organic polysiloxane may include a second organic polysiloxane.
[0080] The second organic polysiloxane may include a hydrogen group bonded to a silicon atom. The number of hydrogen groups per molecule of the second organic poly siloxane may be 1 to 10, 2 to 10, 2 to 5, or 2.
[0081] The second organic poly siloxane may be represented by Formula 5 below:
[0082] [Formula 5]
[0083] In Formula 5, R1may be the hydrogen atom, the hydroxyl group or the saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms, R3may be the hydrogen atom. In addition, in Formula 5, n may be 1 to 1,500, and m may be 0 to 20. In Formula 5, n may be 10 to 1,000, and m may be 0 to 20. In Formula 5, n may be 1 to 1,500, and m may be 0.
[0084] The second organic poly siloxane may be represented by Formula 6 below:
[0085] [Formula 6] A viscosity at about 23°C of the second organic polysiloxane may be about 500 cPs to about 5,000 cPs, about 500 cPs to about 3,000 cPs, or about 500 cPs to about 2,000 cPs.
[0086] The organic polysiloxane may further include a third organic polysiloxane. The third organic polysiloxane may be represented by Formula 7 below:
[0087] [Formula 7]
[0088] In Formula 7, R1may be the hydrogen atom, the hydroxyl group or the saturated or unsaturated monovalent hydrocarbon group having 1 to 18 carbon atoms, and R3may be the hydrogen atom. In addition, in Formula 7, n may be 1 to 1,500, and m may be 1 to 500. In Formula 7, n may be 10 to 1,000, and m may be 1 to 100. The third organic poly siloxane may be represented by Formula 8 below:
[0089] [Formula 8]
[0090] In Formula 8, n may be 1 to 1,500, and m may be 1 to 500. In Formula 8, n may be 10 to 1,000, and m may be 1 to 100. A viscosity at about 23°C of the third organic polysiloxane may be about 50 cPs to about 1,000 cPs, about 100 cPs to about 500 cPs, or about 100 cPs to about 500 cPs.
[0091] A ratio of the viscosity of the first organic poly siloxane to the viscosity of the second organic polysiloxane may be 10: 1 to 40: 1.
[0092] In addition, a ratio of the viscosity of the second organic poly siloxane to the viscosity of the third organic polysiloxane may be 2:1 to 10: 1.
[0093] The content of the first organic poly siloxane may be about 60 parts by weight to about 90 parts by weight, about 70 parts by weight to about 85 parts by weight, or about 75 parts by weight to about 85 parts by weight based on 100 parts by weight of the total organic polysiloxanes.
[0094] The content of the second organic poly siloxane may be about 10 parts by weight to about 40 parts by weight, about 10 parts by weight to about 30 parts by weight, or about 12 parts by weight to about 23 parts by weight based on 100 parts by weight of the first organic polysiloxane.
[0095] The content of the third organic poly siloxane may be about 3 parts by weight to about 20 parts by weight, about 3 parts by weight to about 15 parts by weight, or about 4 parts by weight to about 10 parts by weight based on 100 parts by weight of the first organic polysiloxane.
[0096] When the silicone-based resin composition contains the first organic polysiloxane, the second organic polysiloxane and the third organic polysiloxane in the ranges, it may maintain appropriate adhesive force with an adherend and spread evenly during a coating process.
[0097] The silicone-based resin composition includes a first conductive filler.
[0098] Conventionally, a conductive filler in the form of spherical primary particles was used to improve the heat dissipation properties of a silicone-based resin composition. However, contact characteristics between powders were reduced due to the small surface area of the conductive filler, so there have been a limitation in implementing excellent heat dissipation properties.
[0099] To further improve the heat dissipation properties, the conductive filler was mixed with a flake-type conductive filler with a large specific surface area or a dendrite-type conductive filler. However, when the silicone resin composition contained the flake-type and / or dendrite- type conductive filler, dispersibility with organic polysiloxane was decreased, so that a coverage ratio was significantly decreased. Accordingly, when the silicone-based resin composition is used as a heat conductive layer in a semiconductor device, there is a problem that an area in close contact with a semiconductor package and a heat dissipation part is reduced, and heat dissipation properties deteriorate.
[0100] Accordingly, the present inventors confirmed that, when the first conductive filler included granular secondary particles in which primary particles were agglomerated and the first conductive filler satisfied Equation 1 below, excellent thermal conductivity was exhibited, the reliability of product performance was improved due to a small deviation in thermal conductivity depending upon different pressurizing conditions, and improved coverage, strong adhesive strength and appropriate Junction separation length were exhibited, thereby exhibiting excellent heat dissipation properties:
[0101] [Equation 1]
[0102] 0.3 < A(rn2 / g) / B( m) < 3.0
[0103] In Equation 1, A represents the specific surface area of the first conductive filler and is a value excluding a unit, and B represents the average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
[0104] In general, as the average particle diameter of the conductive filler increases, dispersibility can be improved, but thermal conductivity may be decreased due to a significant reduction of the specific surface area.
[0105] However, the first conductive filler according to the present invention includes granular secondary particles in which primary particles are agglomerated. Here, so long as a ratio of the specific surface area to the average particle diameter of the first conductive filler satisfies Equation 1, it may have a larger specific surface area compared to other conductive fillers with the same average particle diameter.
[0106] Accordingly, the silicone-based resin composition including the first conductive filler according to the present invention can not only implement may realize the excellent coverage characteristics of conventional spherical conductive fillers, but also can realize the excellent coverage characteristics of conventional flake-type and dendrite-type conductive fillers.
[0107] In Equation 1, A may be 0.8 m2 / g to 2.0 m2 / g, 0.8 m2 / g to 1.8 m2 / g, 0.8 m2 / g to 1.6 m2 / g, or 0.8 m2 / g to 1.5 m2 / g.
[0108] In Equation 1, B may be 0.5 pm to 10 pm, 0.5 pm to 5 pm, 0.5 pm to 4 pm, or 1 pm to
[0109] 4 pm.
[0110] The average particle diameter is defined as a particle size corresponding to 50% of a cumulative volume in a particle size distribution curve derived from the conductive powder using a laser diffraction method.
[0111] In Equation 1, A(m2 / g) / B(prn) may be greater than 0.3 and less than 3.0, greater than 0.3 and 2.5 or less, greater than 0.3 and 2.0 or less, or 0.4 or more and 2.0 or less. When the ranges are satisfied, excellent coverage characteristics, improved coverage and an appropriate spread thickness may be provided.
[0112] The primary particles may be flaky particles. When the primary particles are flaky particles, the mechanical strength of the secondary particles in which the primary particles are agglomerated may be improved, so that the thermal conductivity deviation may be decreased and the reliability of product performance may be further improved.
[0113] The first conductive filler may be an aggregate of secondary particles in which flaky silver particles are agglomerated. The secondary particles may have a spherical shape.
[0114] The secondary particles may be formed by spray drying the primary particles to be agglomerated, followed by firing.
[0115] The primary particles may have an average particle diameter (D50) off 0.1 m to 1 m,
[0116] 0.1 pm to 0.9 pm, 0.1 pm to 0.8 pm, or 0.1 pm to 0.5 pm.
[0117] The first conductive filler may have an aspect ratio of 0.5 to 3, 0.6 to 3, 0.6 to 2.8, 0.6 to 2.7, or 0.5 to 2.5.
[0118] The aspect ratio is defined as a length of the major axis of the first conductive filler particle divided by the length of the minor axis of the first conductive filler particle.
[0119] The first conductive filler may have a tapped density of 0.5 g / cm3to 6 g / cm3, 1 g / cm3to 6 g / cm3, 1.5 g / cm3to 6 g / cm3, or 2.5 g / cm3to 6 g / cm3.
[0120] To obtain the tapped density, about 100 g of the first conductive powder is weighed, and it is lightly dropped into a 100 ml measuring cylinder using a funnel. Next, the cylinder is placed on a tap density meter, and the powder is compressed by dropping 600 times at a speed of 60 times / min with a drop distance of 20 mm. The tapped density is calculated from the volume of the compressed conductive powder.
[0121] Since the first conductive filler includes granular secondary particles in which primary particles were agglomerated, the mechanical properties may be greatly affected by the hardness of the first conductive filler. The first conductive filler may have a Mohs hardness of 2 to 5, 2 to 4.5, 2 to 4, 2 to 3, or 2.5 to 3. The Mohs hardness may be measured using a Mohs hardness meter. When the range is satisfied, the phenomenon of greatly deforming the shape of the first conductive filler or breaking it due to the occurrence of multiple cracks may be minimized during the pressurization process after the silicone-based resin composition has hardened, spherical
[0122] The first conductive filler may be surface-treated with a surface treatment agent. The surface treatment agent may include a CIO to C20 fatty acid. Examples of the fatty acid include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, myristoleic acid, palmitolic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linolelaidic acid, arachidonic acid, eicosapentaenoic acid, a-linolenic acid, and the like.
[0123] The first conductive filler may have an ignition loss (Ig-loss) of less than about 0.8 % by weight, less than about 0.7 % by weight, less than about 0.6 % by weight, less than about 0.5 % by weight, less than about 0.4 % by weight, less than about 0.3 % by weight, less than about 0.2 % by weight, or about 0.01 % by weight or more and less than about 0.4 % by weight. The ignition loss may be performed and measured for about 1 hour at about 538°C.
[0124] The surface of the first conductive filler may be effectively treated even with a small amount of the surface treatment agent. That is, the first conductive filler has a relatively low tap density and a large specific surface area, and may be surface-treated with a small amount of a surface treatment agent. Accordingly, the first conductive filler may be uniformly dispersed in the organic poly siloxane and may improve thermal connection of the conductive filler. That is, since the first conductive filler has improved dispersibility, the first conductive filler may be added in a high content to the organic polysiloxane.
[0125] The silicone-based resin composition may include the first conductive filler in a content of about 300 parts by weight to about 1,000 parts by weight, about 400 parts by weight to about 900 parts by weight, or about 500 parts by weight to about 800 parts by weight based on 100 parts by weight of the organic poly siloxane. When the range is satisfied, proper adhesion to an adherend may be maintained, and durability may be improved because voids and cracks due to thermal shock do not occur.
[0126] The silicone-based resin composition may further include a spherical second conductive filler having a shape different from the first conductive filler. The second conductive filler may be formed of spherical primary particles. Since the silicone-based resin composition includes the first conductive filler including granular secondary particles and the second conductive filler including spherical primary particles, the mechanical strength of the conductive fillers capable of improving thermal conductivity may be further improved, so that a thermal conductivity deviation may be reduced, and the reliability of product performance may be improved.
[0127] The second conductive filler may have an aspect ratio of 1 to 1.5, 1 to 1.45, 1 to 1.4, 1 to 1.35, or 1 to 1.3.
[0128] As the aspect ratio approaches 1, the shape of the second conductive filler particles may be interpreted as being almost spherical.
[0129] The aspect ratio is defined as the length of the major axis of the second conductive filler particle divided by the length of the minor axis of the second conductive filler particle.
[0130] The second conductive filler may have a roundness of 0.95 to 1, 0.96 to 1, 0.97 to 1, or 0.98 to 1.
[0131] As the roundness approaches 1, the shape of the second conductive filler particles may be interpreted as being almost spherical.
[0132] The roundness may be calculated according to the following calculation equation:
[0133] [Calculation equation] roundness = (4 * area) / (7t x major axis length2)
[0134] The second conductive filler may have a specific surface area of 0.1 m2 / g to 1.0 m2 / g, 0.1 m2 / g to 0.9 m2 / g, 0.1 m2 / g to 0.8 m2 / g, or 0.1 m2 / g to 0.5 m2 / g.
[0135] With regard to a weight ratio, the first conductive filler : the second conductive filler may be 1 :1 to 1 :5, 1 :1 to 1 :4.5, 1 : 1 to 1 :4, or 1 : 1 to 1 :3. When the ranges are satisfied, a cured product made of the silicone-based resin composition may have an improved coverage and an appropriate spread thickness while realizing high thermal conductivity. FIG. 1 is a sectional view illustrating a process of measuring the lap shear strength and Junction separation length of a silicone-based resin composition.
[0136] Referring to FIG. 1, a silicone-based resin composition 30 with a thickness of about 200 m is coated on a certain region of the first nickel plate 20, and then the second nickel plate 10 covers the coated silicone-based resin composition 30. Next, the silicone-based resin composition 30 is cured at about 150 °C for about 2 hours. The coated area of the silicone- based resin composition 30 may be about 2.5 cm* 1.25 cm. Next, the first nickel plate 20 and the second nickel plate 10 are pulled in directions opposite to each other in a horizontal direction by a universal testing machine. Here, depending on the length deformed in the horizontal direction, the stress in the horizontal direction is measured on the first nickel plate 20 and the second nickel plate 10.
[0137] The lap shear strength may be the maximum value of stress applied to the first nickel plate 20 and the second nickel plate 10 divided by the coated area of the silicone-based resin composition 30.
[0138] The Junction separation length may be the length transformed in the horizontal direction at the maximum value of the stress applied to the first nickel plate 20 and the second nickel plate 10.
[0139] A lap shear strength of the silicone-based resin composition measured by DIN EN 1465 may be 1 N / mm2or more, 1.2 N / mm2or more, 1.3 N / mm2or more, 1.4 N / mm2or more, or 1.5 N / mm2to 2.5 N / mm2.
[0140] The Junction separation length measured by DIN EN 1465 may be 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, or 0.5 mm to 1.0 mm.
[0141] When the ranges are satisfied, both the bonding stability and heat dissipation properties of the heat conductive layer may be improved.
[0142] A shear modulus expressed by the following equation may be 1 N / mm3or more and less than 3 N / mm:
[0143] [Equation]
[0144] Shear modulus (N / mm3) = LSS(N / mm2) / JSL(mm) where LSS represents the lap shear strength of the silicone-based resin composition measured by DIN EN 1465, and JSL represents the Junction separation length of the silicone- based resin composition measured by the DIN EN 1465.
[0145] The shear modulus may be 1 N / mm3or more and less than 3 N / mm3, 1.1 N / mm3or more and less than 3 N / mm3, 1.3 N / mm3or more and 2.5 N / mm3or less, or 1.6 N / mm3or more and 2.5 N / mm3or less.
[0146] When the ranges are satisfied, deformation and peeling due to shear stress may be suppressed, and deformation caused by external thermal shock may be easily restored.
[0147] The coverage of the silicone-based resin composition measured by Measurement Method 1 below may be 90 % or more, 92 % or more, 94 % or more, 96 % or more, or 99 % or more.
[0148] [Measurement Method 1]
[0149] 1) The silicone-based resin composition is coated in a weight of 0.7 g on the first silicone substrate having a size of 27 mm><27 mm.
[0150] 2) The second silicone substrate, which has a size the same as or larger than the first silicone substrate, is placed on the coated silicone-based resin composition, and then the silicone- based resin composition is cured in a state of being compressed with a force of 3 kgf.
[0151] 3) An area where the first silicone substrate is in close contact with the second silicone substrate by the cured silicone-based resin composition is derived.
[0152] 4) The coverage is a ratio of an area of the first silicon substrate in close contact with the second silicon substrate compared to a planar area of the first silicon substrate.
[0153] In addition, the thickness of the cured resin composition layer may be a spread thickness.
[0154] Since the silicone-based resin composition has the above coverage and spread thickness, the heat conductive layer may be in close contact with the semiconductor package and the heat dissipation part over a large area and may have high heat conduction characteristics when the silicone-based resin composition is used as a heat conductive layer of a semiconductor device.
[0155] The silicone-based resin composition may have a viscosity of 50,000 cPs to 200,000 cPs, 50,000 cPs to 180,000 cPs, 70,000 cPs to 180,000 cPs, or 70,000 cPs to 150,000 cPs. The viscosity of the silicone-based resin composition may be measured by the DIN EN ISO 3219 method at about 25°C using a rheometer MCR302 (manufacturer: Anton Paar GmbH) equipped with a plate with a diameter of about 25 mm. Here, a shear rate of about 10 (1 / s) may be applied to measure the viscosity.
[0156] When the ranges are satisfied, appropriate coverage and spread thickness may be obtained.
[0157] The silicone-based resin composition may have a pot life of 10 hours to 16 hours, 10 hours to 15 hours, 10 hours to 14 hours, or 10 hours to 13 hours.
[0158] The pot life may be measured by the following method.
[0159] The silicone-based resin composition is allowed to stand at room temperature. Next, the time it takes for the viscosity of the silicone-based resin composition to increase by 50% compared to an initial viscosity thereof is measured as a pot life.
[0160] A thermal conductivity change rate of the silicone-based resin composition measured by Measurement Method 2 below may be less than 30 %:
[0161] [Measurement Method 2]
[0162] 1) The silicone-based resin composition was molded by heat press for 15 minutes under conditions of 165°C and a pressure of 10 kgf / cm2to manufacture a first sheet, and separately, the silicone-based resin composition was molded by heat press for 15 minutes under conditions of 165°C and a pressure of 0.1 kgf / cm2to manufacture a second sheet.
[0163] 2) The first sheet and the second sheet were cured at 150°C for 2 hours to respectively manufacture a sample of the first sheet and a sample of the second sheet.
[0164] 3) A thermal conductivity of the first sheet sample and a thermal conductivity of the second sheet sample were measured at 25°C according to ISO 22007-2.
[0165] 4) The thermal conductivity change rate was calculated according to Equation 2 below:
[0166] [Equation 2]
[0167] Thermal conductivity change rate(%) = ( | TCio - TCo.i | / TCio)x100
[0168] In Equation 2, where TCio is a thermal conductivity (W / mK) of the first sheet sample, and TCo.i is a thermal conductivity (W / mK) of the second sheet sample.
[0169] A thermal conductivity change rate of the silicone-based resin composition measured by Measurement Method 2 may be less than 30%, 25% or less, 20% or less, 15% or less, or 10% or less.
[0170] Since the silicone-based resin composition has the thermal conductivity change rate, the reliability of product performance may be secured due to a small deviation in the thermal conductivity change rate even the silicone-based resin composition is used for commercialization under different pressurizing conditions. In addition, it may maintain appropriate adhesive force to an adherend even when thermal shock is applied to products manufactured using the silicone- based resin composition, and the occurrence of voids and cracks due to thermal shock may be prevented.
[0171] A relative ratio of a change in thermal conductivity to a change in Shore A hardness of the silicone-based resin composition measured by the following measurement method 3 may be 40% or less:
[0172] [Measurement Method 3]
[0173] 1) The silicone-based resin composition is molded by heat press under conditions of 165°C and a pressure of 26 kgf / cm2for 15 minutes to manufacture a sheet.
[0174] 2) The sheet is cured at 150°C for 5 minutes to manufacture a first cured product. The first cured product is subjected to measurement of a Shore A hardness according to ASTM D- 2240 and measurement of a thermal conductivity according to ISO 22007-2 at 25°C.
[0175] 3) The first cured product is cured at 150°C for 120 minutes to manufacture a second cured product. The second cured product is subjected to measurement of a Shore A hardness according to ASTM D-2240 and measurement of a thermal conductivity according to ISO 22007-2 at 25°C temperature.
[0176] 4) A relative ratio of a change in thermal conductivity to a change in Shore A hardness is calculated according to the following equation:
[0177] [Equation] 100 where Hl denotes the Shore A hardness of the first cured product, H2 denotes the Shore A hardness of the second cured product, TCHI denotes a thermal conductivity (W / mK) in Hl, and TCH2 denotes a thermal conductivity (W / mK) in H2.
[0178] In the silicone-based resin composition, a relative ratio of a change in thermal conductivity to a change in Shore A hardness measured by Measurement Method 3 may be 35% or less, 30% or less, 25% or less, 20% or less, 10% or less, 5% or less, or 1% or less.
[0179] A variation in hardness of products manufactured from the silicone-based resin composition may occur depending upon a curing temperature, a curing time, or the composition of the silicone-based resin composition.
[0180] Since a relative ratio of a change in thermal conductivity to a change in Shore A hardness, measured by the measurement method, of the silicone-based resin composition is 40% or less, a change in thermal conductivity compared to a change in hardness is significantly reduced, a thermal conductivity value capable of performing an appropriate heat dissipation function is exhibited, and reliability may be improved when applying a product that needs to perform a heat dissipation function due to a small thermal conductivity variation even if a variation occurs in hardness of a product manufactured from the silicone-based resin composition.
[0181] A Shore A hardness according to ASTM D-2240 of a cured product of the silicone-based resin composition may be 95 or less, 85 or less, 75 or less, 65 or less, 60 or less, 10 to 60 or less, 20 to 60 or less, or 30 to 60 or less. When the hardness is within the range, the occurrence of abrasion or cracking during product manufacturing may be minimized.
[0182] The silicone-based resin composition may satisfy the following equation:
[0183] [Equation]
[0184] Y = 0.0169X + 6.5193 where X denotes a Shore A hardness according to ASTM D-2240 in a cured product of the silicone-based resin composition, Y denotes a thermal conductivity according to ISO 22007-2 at 25°C of a cured product of the silicone-based resin composition, and Y is 6 W / mK to 8 W / mK.
[0185] A coefficient of determination (R2) of X in a range of 3 to 57 may be 0.95 or more.
[0186] Equation denotes a linear trend line with a Shore A hardness as an X variable and a thermal conductivity, which is a dependent variable according to the X variable, as Y. The linear trend line may be derived using Microsoft's Excel program, and a coefficient of determination (R2) may be obtained from the linear trend line. The coefficient of determination, which is a statistical term, is a measure of the goodness of fit of a well-known regression equation and represents a ratio of the sum of fluctuations to the total sum of fluctuations of Yi with respect to data Yi of a dependent variable Y. The coefficient of determination is generally represented by R2, and the goodness of fit of the regression equation increases as the coefficient of determination approaches 1.
[0187] For example, in Equation, Y is 6.6 to 7.4 in a range where X is 3 to 57, which means that a thermal conductivity in a range where the Shore A hardness is 3 to 57 is 6.6 W / mK to 7.4 W / mK. Here, the coefficient of determination (R2) represents 0.95 or more. Accordingly, even if a variation in hardness is large, a variation in thermal conductivity is not relatively large, which may indicate that the goodness of fit of the regression equation is high. Therefore, the silicone-based resin composition that satisfies the equation may satisfy the reliability of product performance due to a small variation in thermal conductivity even if there is a variation in hardness.
[0188] The silicone-based resin composition includes a curing catalyst.
[0189] The curing catalyst may accelerate the curing of the silicone-based resin composition.
[0190] Examples of the curing catalyst include organic titanate esters such as platinum- divinyltetramethyldisiloxane complex, tetrabutyl titanate, and tetraisopropyl titanate; organic titanium chelate compounds such as diisopropoxybis(acetylacetate)titanium and diisopropoxybis(ethylacetoacetate)titanium; organoaluminum compounds such as aluminum tris(acetylacetonate) and aluminum tri s(ethyl acetoacetate); organic zirconium compounds such as zirconium tetra(acetylacetonate) and zirconium tetrabutylate; organic tin compounds such as dibutyltin dioctoate, dibutyltin dilaurate, and butyltin-2-ethylhexoate; metal salts of organic carboxylic acids such as tin naphthenate, tin oleate, tin butyrate, cobalt naphthenate, and zinc stearate; amine compounds such as hexylamine and dodecylamine phosphate and salts thereof; quaternary ammonium salts such as benzyltriethylammonium acetate; lower fatty acid salts of alkali metals such as potassium acetate; dialkyl hydroxylamines such as dimethylhydroxylamine and diethylhydroxylamine; and guanidyl group-containing organosilicon compounds.
[0191] The silicone-based resin composition may include the curing catalyst in a content of about 0.01 parts by weight to about 5 parts by weight, about 0.03 parts by weight to about 3 parts by weight, or about 0.1 parts by weight to about 2 parts by weight based on 100 parts by weight of the organic poly siloxane. The silicone-based resin composition may further include a tackifier.
[0192] The tackifier may include alkoxysilane. In addition, the tackifier may include an epoxy group. The tackifier may be at least one selected from the group consisting of 2-(3,4 epoxy cyclohexyl) ethyltrimethoxy silane, 3-glycidoxypropyl methyldimethoxy silane, 3- glycidoxypropyl trimethoxy silane, 3-glycidoxypropyl methyldi ethoxy silane, and 3- glycidoxypropyl triethoxysilane.
[0193] The silicone-based resin composition may include the tackifier in a content of about 1 part by weight to about 20 parts by weight, about 1 part by weight to about 10 parts by weight, or about 2 parts by weight to about 8 parts by weight based on 100 parts by weight of the organic polysiloxane. The tackifier may improve adhesive strength between the organic polysiloxane and the conductive filler.
[0194] The silicone-based resin composition may further include a reaction inhibitor. The reaction inhibitor may be at least one selected from the group consisting of acetylenic compounds such as 2-methyl-3-butyn-2-ol, 2-phenyl-3-butyn-2-ol, and 1-ethynyl-l- cyclohexanol; ene-yne compounds such as 3-methyl-3-penten-l-yne and 3,5-dimethyl-3-hexen- 1-yne; curing reaction inhibitors such as hydrazine-based compounds, phosphine-based compounds, and mercaptan-based compound; and the like.
[0195] The silicone-based resin composition may include the reaction inhibitor in a content of about 0.0001 parts by weight to about 10 parts by weight based on 100 parts by weight of the organic polysiloxane.
[0196] A method of preparing the silicone-based resin composition may be a known preparation method, without being specifically limited.
[0197] For example, the silicone-based resin composition may be prepared by mixing the organic polysiloxane, the conductive filler, the curing catalyst, the tackifier, the reaction inhibitor, and the like for 30 minutes to 4 hours using a mixer such as Trimix, Twinmix, and a planetary mixer (all of which are manufactured by Inoue Seisakusho Co., Ltd., registered trademark); Ultramixer (manufactured by Mizuho Kogyo Co., Ltd., registered trademark); or Hibis Disper Mix (manufactured by Primix Co., Ltd., registered trademark). In the mixing process, a process temperature may be about 0°C to about 25°C. FIG. 2 is a sectional view illustrating a cross section of a semiconductor device according to an embodiment of the present invention.
[0198] Referring to FIG. 2, the semiconductor device according to the present invention includes a semiconductor package 200, a heat dissipation part 400 placed on the semiconductor package 200, and a heat conductive layer 500 interposed between the semiconductor package 200 and the heat dissipation part 400.
[0199] The semiconductor device may include a circuit board 100 and conductive bumps 300.
[0200] The circuit board 100 may support the semiconductor package 200, the conductive bumps 300, the heat dissipation part 400 and the heat conduction layer 500.
[0201] The circuit board 100 may include a circuit pattern. The circuit board 100 may include a plurality of circuit patterns disposed inside a flat body including an insulating and heat- resistant material and having a predetermined strength. In addition, the circuit board 100 may include a connection pad electrically connected to the circuit pattern and disposed on the body.
[0202] The body of the circuit board 100 may include a thermosetting resin-based substrate such as an epoxy resin substrate or a polyimide substrate, a flat plate, or a flat plate attached with a heat-resistant organic film such as a liquid crystal polyester film or a polyamide film. The circuit pattern may be disposed inside the body in a pattern shape and may include power wiring for power supply, ground wiring, and signal wiring for signal transmission. Each wiring may be disposed to be separated from each other by a plurality of interlayer insulating films formed on upper and lower surfaces of the body.
[0203] The connection pad may be exposed to the outside from the upper surface of the body and may be connected to the circuit pattern. Therefore, an external connection body connected to the circuit board 100 may be electrically connected to an internal circuit pattern through the connection pad.
[0204] Various electronic components may be mounted on a connection pad included in the circuit board 100. The circuit board 100 may be a system board on which electronic components including the semiconductor package 200 are mounted.
[0205] The semiconductor package 200 may be mounted on the circuit board 100. The semiconductor package 200 may be disposed on the circuit board 100. The semiconductor package 200 may be connected to the circuit board 100 through the conductive bumps 300.
[0206] The semiconductor package 200 may include a semiconductor chip including an integrated circuit, a semiconductor package substrate connected to the semiconductor chip, a conductive solder for connecting the semiconductor chip and the semiconductor package substrate, and a sealing part for sealing the semiconductor chip and the conductive solder. The sealing part may include a resin composition such as epoxy molding.
[0207] The semiconductor package 200 may be a memory device, a central processing unit, or the like.
[0208] The conductive bumps 300 may be disposed between the semiconductor package 200 and the circuit board 100. The conductive bumps 300 may electrically connect the semiconductor package 200 and the circuit board 100 to each other. The conductive bumps 300 may be electrically connected to the semiconductor package 200 and the connection pad.
[0209] The heat dissipation part 400 may be disposed on the semiconductor package 200. The heat dissipation part 400 may cover the semiconductor package 200. The heat dissipation part 400 may be bonded to the circuit board 100. The heat dissipation part 400 may cover a side surface of the semiconductor package 200.
[0210] The heat dissipation part 400 may include a conductor. The heat dissipation part 400 may include metal. The heat dissipation part 400 may be thermally connected to an external heat dissipation fin.
[0211] The heat dissipation part 400 may protect the semiconductor package 200 against external physical impact. The heat dissipation part 400 may protect the semiconductor package 200 against external electromagnetic waves. That is, the heat dissipation part 400 may block external electromagnetic waves.
[0212] The heat conduction layer 500 may be disposed between the semiconductor package 200 and the heat dissipation part 400. The heat conduction layer 500 may directly contact the semiconductor package 200 and the heat dissipation part 400. The heat conduction layer 500 may be in close contact between the semiconductor package 200 and the heat dissipation part 400.
[0213] The heat conduction layer 500 may be thermally connected to the semiconductor package 200 and the heat dissipation part 400. That is, the heat conduction layer 500 may transfer heat generated from the semiconductor package 200 to the heat dissipation part 400. The thickness of the heat conduction layer 500 may be about 1 pm to about 100 pm, about 2 pm to about 70 pm, about 5 pm to about 60 pm, or about 10 pm to about 40 pm.
[0214] The heat conductive layer 500 includes a silicone-based resin composition. The silicone-based resin composition includes an organic polysiloxane, a first conductive filler, and a curing catalyst. The first conductive filler includes secondary particles in which primary particles are agglomerated. The first conductive filler satisfies Equation 1 below:
[0215] [Equation 1]
[0216] 0.3 < A(m2 / g) / B(pm) < 3.0
[0217] In Equation 1, A represents the specific surface area of the first conductive filler and is a value excluding a unit, and B represents the average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
[0218] The silicone-based resin composition may be the same as the silicone-based resin composition described above. Since the first conductive filler of the silicone-based composition includes secondary particles in which primary particles are agglomerated, and the ratio of the specific surface area to the average particle diameter expressed by Equation 1 of the first conductive filler satisfies greater than 0.3 and less than 3.0, the thermal conductivity of the heat conductive layer 500 including the silicone-based composition may be improved. In addition, the heat conductive layer 500 may maintain appropriate adhesive force to the semiconductor package 200 and the heat dissipation part 400, so the heat dissipation function may be improved.
[0219] A method of manufacturing the semiconductor device may be a known manufacturing method, without being specifically limited.
[0220] First, the semiconductor package 200 may be mounted on the circuit board 100 by the conductive bumps 300. Next, the silicone-based resin composition may be coated on the semiconductor package 200. Alternatively, the silicone-based resin composition may be coated on a lower surface of the heat dissipation part 400.
[0221] Next, the heat dissipation part 400 may cover the semiconductor package 200. Accordingly, the coated silicone-based resin composition may be in direct contact with the lower surface of the heat dissipation part 400 and the upper surface of the semiconductor package 200, and the curable silicone resin composition may be cured at about 80°C or more in a state in which a pressure of about 0.01 MPa or more is applied.
[0222] A pressure in the curing process may be about 0.01 MPa or more. The pressure in the curing process may be about 0.05 MPa to about 100 MPa. The pressure in the curing process may be about 0.1 MPa to about 100 MPa.
[0223] A temperature in the curing process may be about 110°C to about 300°C. The temperature in the curing process may be about 120°C to about 300°C. The temperature in the curing process may be about 140°C to about 300°C. A curing time in the curing process may be about 30 minutes to about 20 hours. The heat conduction layer 500 may be formed by the process.
[0224] Hereinafter, the present invention is described in more detail based on Examples and Comparative Examples. However, the following Examples and Comparative Examples are only examples for explaining the present invention in more detail, and the present invention is not limited by the following Examples and Comparative Examples.
[0225] Example
[0226] - Organic poly siloxane #1 : Compound represented by the following Formula 4 having a viscosity of 20,000 cPs at 23°C and including a silicon-bonded alkenyl group:
[0227] [Formula 4]
[0228] - Organic poly siloxane #2: Compound represented by the following Formula 6 having a viscosity of 1,000 cPs at 23 °C and including a structure in which hydrogen groups are bonded to both ends thereof:
[0229] [Formula 6]
[0230] - Organic polysiloxane #3: Compound represented by the following Formula 8 having a viscosity of 1,000 cPs at 23°C and including a structure in which a hydrogen group is bonded to a side chain thereof
[0231] [Formula 8]
[0232] - Conductive filler #1 : Granular silver powder in which primary particles having an average particle diameter (D50) of about 0.3 m are agglomerated. The granular silver powder having an average particle diameter (D50) of about 2.5 pm, an aspect ratio of about 2, a specific surface area of about 2.5 m2 / g, and a tapped density of about 3 g / cm3
[0233] - Conductive filler #2: Granular silver powder in which primary particles having an average particle diameter (D50) of about 1 pm are agglomerated. The granular silver powder having an average particle diameter (D50) of about 5 pm, an aspect ratio of about 2, a specific surface area of about 2 m2 / g, and a tapped density of about 5 g / cm3
[0234] - Conductive filler #3 : Granular silver powder in which primary particles having an average particle diameter (D50) of about 0.1 pm are agglomerated. The granular silver powder having an average particle diameter (D50) of about 1 pm, an aspect ratio of about 2, a specific surface area of about 4 m2 / g, and a tapped density of about 4.5 g / cm3
[0235] - Conductive filler #4: Granular silver powder in which primary particles having an average particle diameter (D50) of about 0.4 pm are agglomerated. The granular silver powder having an average particle diameter (D50) of about 6.5 pm, an aspect ratio of about 1.5, a specific surface area of about 1.5 m2 / g, and a tapped density of about 4 g / cm3
[0236] - Conductive filler #5: Spherical silver powder having an average particle diameter (D50) of about 2.5 m, an aspect ratio of about 1.1, a specific surface area of about 0.3 m2 / g, and a tapped density of about 6.4 g / cm3- Conductive filler #6: Flake-type silver powder having an average particle diameter
[0237] (D50) of about 1.2 m, an aspect ratio of about 11, a specific surface area of about 0.4 m2 / g, and a tapped density of about 5 g / cm3
[0238] - Tackifier: 3-glycididoxy propyltrimethoxy silane
[0239] - Curing catalyst: Platinum-divinyltetramethyldisiloxane complex - Reaction inhibitor: 1-ethynyl-l -cyclohexanol
[0240] Examples 1 to 6 and Comparative Examples 1 to 4
[0241] A silicone-based resin composition was prepared by adding each composition shown in Table 1 below to a planetary mixer and uniformly mixing at room temperature at a speed of about 40 rpm for 1 hour.
[0242] [Table 1]
[0243] Experimental examples
[0244] Experimental Example 1 - Measurement of thermal conductivity
[0245] The silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was molded into a size of 30 mm><30 mm mm by heat press. Next, it was cured at about 150 °C for 2 hours to manufacture a sample. Next, the thermal conductivity of the sample of each of Examples 1 to 6 and Comparative Examples 1 to 4 was measured using a thermal conductivity analyzer (model name: TPS-2500S, manufacturer: Hot Disk AB) according to ISO 22007-2 at 25°C. Results are shown in Table 2 below.
[0246] Experimental Example 2 - Thermal shock test
[0247] The silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was allowed to stand at -40°C for 30 minutes and was allowed to stand at 125 °C for 30 minutes. This cycle was repeated about 500 times, and then the thermal conductivity was measured in the same manner as in Experimental Example 1. Results are shown in Table 2 below.
[0248] Experimental Example 3 - Measurement of lap shear strength and Junction separation length
[0249] The silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was coated to a thickness of about 200 m on an area of about 2.5 cm* 1.25 cm of the first nickel plate, and then covered with the second nickel plate. Next, the first and second nickel plates were pre-cured at 135°C for about 10 minutes while being compressed with a weight of 3 kgf. Next, the first nickel plate and the second nickel plate were subjected to lap shear strength and Junction separation length measurement according to DIN EN 1465 while being stretched in opposite directions by a universal testing machine (tensile strength analyzer, manufactured by ZwickRoell Gmbh). Results are shown in Table 2 below.
[0250] Experimental Example 4 - Measurement of coverage and spread thickness
[0251] 0.7 g of the silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was coated on the first silicone substrate having a size of about 27 mm x 27 mm, and then covered with the second silicone substrate having the same size as the first silicone substrate. Next, it was pre-cured at 135°C for about 10 minutes while applying a force of about 3 kgf to the second silicone substrate. Next, it was cured at 150°C for about 2 hours. Next, the area in which the first silicon substrate and the second silicon substrate were in close contact with the cured coating layer was measured using SAT ultrasonic inspection equipment and an image particle analyzer, and a ratio of the contact area to the total planar area was derived. Results are shown in Table 2 below.
[0252] Experimental Example 5 - Viscosity measurement
[0253] The viscosity of the silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was measured at about 25°C according to the DIN EN ISO 3219 method by a rheometer (product name: MCR302, manufacturer: Anton Paar GmbH) using a circular plate with a diameter of 25 mm. Here, the viscosity was measured at a shear rate of about 10(l / s). Results are shown in Table 2 below. Experimental Example 6 - Pot life measurement
[0254] The silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was allowed to stand at room temperature, and then the time taken for the viscosity to increase by 50% compared to the initial viscosity was measured. Results are shown in Table 2 below.
[0255] [Table 2]
[0256] Experimental Example 7 - Measurement of thermal conductivity change rate
[0257] The silicone-based resin composition of each of Examples 1 to 6 and Comparative Examples 1 to 4 was molded at 165°C under a pressure condition shown in Table 3 below by heat press to manufacture a sheet. Next, the sheet was cured at 150°C for 2 hours, and then manufactured into a sample having a width of 30 mm, a length of 30 mm, and a thickness of 4 mm. Next, the thermal conductivity of the samples manufactured in Examples 1 to 6 and Comparative Examples 1 to 4 was measured according to the ISO 22007-2 method at 25°C using a thermal conductivity analyzer (model name: TPS-2500S, manufacturer: Hot Disk AB). Results are shown in Table 3 below.
[0258] [Table 3]
[0259] Referring to Tables 1 to 3, the silicone-based resin compositions of Examples 1 to 6 include a granular conductive powder in which primary particles are agglomerated, and the specific surface area to the average particle diameter (Dso) of the conductive powder is greater than 0.3 and less than 3.0.
[0260] Therefore, it can be confirmed that the silicone-based resin compositions of Examples 1 to 6 have excellent thermal conductivity, improved coverage, relatively strong adhesive strength and appropriate Junction separation length while having the same conductive filler as the silicone-based resin compositions of Comparative Examples 1 to 4. In addition, since the silicone-based resin compositions of Examples 1 to 6 exhibit a low thermal conductivity change rate, it can be confirmed that they can perform appropriate heat dissipation functions and exhibit improved product performance reliability even when manufactured for commercialization under different pressurizing conditions. [Description of Symbols]
[0261] 10: second nickel plate
[0262] 20: first nickel plate
[0263] 30: silicone-based resin composition 100: circuit board
[0264] 200: semiconductor package
[0265] 300: conductive bump
[0266] 400: heat dissipation part
[0267] 500: heat conductive layer
Claims
[CLAIMS]
1. A silicone-based resin composition, comprising: an organic polysiloxane; a first conductive filler; and a curing catalyst, wherein the first conductive filler comprises secondary particles in which primary particles are agglomerated, wherein the first conductive filler satisfies Equation 1 below:[Equation 1]0.3 < A(m2 / g) / B( ni) < 3.0 where A represents a specific surface area of the first conductive filler and is a value excluding a unit, and B represents an average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
2. The silicone-based resin composition according to claim 1, wherein the primary particles are flaky particles.
3. The silicone-based resin composition according to claim 1, wherein the first conductive filler has an aspect ratio of 0.5 to 3.
4. The silicone-based resin composition according to claim 1, wherein the first conductive filler has a tapped density of 0.5 g / cm3to 6 g / cm3.
5. The silicone-based resin composition according to claim 1, wherein the silicone-based resin composition further comprises a spherical second conductive filler different from the first conductive filler.
6. The silicone-based resin composition according to claim 5, wherein the second conductive filler has an aspect ratio of 1 to 1.5.
7. The silicone-based resin composition according to claim 5, wherein a weight ratio of the first conductive fillerthe second conductive filler is 1 : 1 to 1 :5.
8. The silicone-based resin composition according to claim 1, wherein a lap shear strength of the silicone-based resin composition measured by DIN EN 1465 is 1 N / mm2or more.
9. The silicone-based resin composition according to claim 1, wherein a coverage, measured by Measurement Method 1 below, of the silicone-based resin composition is 90 % or more:[Measurement Method 1]1) the silicone-based resin composition is coated in a weight of 0.7 g on a first siliconesubstrate having a size of 27 mm *27 mm,2) a second silicone substrate, which has a size the same as or larger than the first silicone substrate, is placed on the coated silicone-based resin composition, and then the silicone- based resin composition is cured in a state of being compressed with a force of 3 kgf,3) an area where the first silicone substrate is in close contact with the second silicone substrate by the cured silicone-based resin composition is derived, and4) the coverage is a ratio of an area of the first silicon substrate in close contact with the second silicon substrate compared to a planar area of the first silicon substrate.
10. The silicone-based resin composition according to claim 1, wherein a thermal conductivity change rate of the silicone-based resin composition measured by Measurement Method 2 below is less than 30 %:[Measurement Method 2]1) the silicone-based resin composition is molded by heat press for 15 minutes under conditions of 165°C and a pressure of 10 kgf / cm2to manufacture a first sheet, and separately, the silicone-based resin composition is molded by heat press for 15 minutes under conditions of 165°C and a pressure of 0.1 kgf / cm2to manufacture a second sheet,2) the first sheet and the second sheet are cured at 150°C for 2 hours to respectively manufacture a sample of the first sheet and a sample of the second sheet,3) a thermal conductivity of the first sheet sample and a thermal conductivity of the second sheet sample are measured at 25°C according to ISO 22007-2,4) a thermal conductivity change rate is calculated according to Equation 2 below:[Equation 2]Thermal conductivity change rate(%) = ( | TCio - TCo.i | / TCio)x100 where TCio is a thermal conductivity (W / mK) of the first sheet sample, and TCo.i is a thermal conductivity (W / mK) of the second sheet sample.
11. A semiconductor device, comprising: a semiconductor package; a heat dissipation part disposed on the semiconductor package; and a heat conduction layer interposed between the semiconductor package and the heat dissipation part, wherein the heat conductive layer comprises a silicone-based resin composition, wherein the silicone-based resin composition comprises an organic polysiloxane, a first conductive filler, and a curing catalyst, wherein the first conductive filler comprises secondary particles in which primary particles are agglomerated, and the first conductive filler satisfies Equation 1 below:[Equation 1]0.3 < A(m2 / g) / B( ni) < 3.0 where A represents a specific surface area of the first conductive filler and is a value excluding a unit, and B represents an average particle diameter (D50) of the first conductive filler and is a value excluding a unit.
Citation Information
Patent Citations
Organic silicon resin conductive adhesive, and preparation method therefor and application thereof
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