JP2016204645A - Heat curable resin composition for encapsulation, manufacturing method of semiconductor device and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat curable resin composition for encapsulation suitable for encapsulating between a substrate and a semiconductor chip by pre-supply system under filling, high in flowability, high in curable rate, high in heat resistance of a cured article and capable of suppressing defective conduction between the conductor chip and the substrate.SOLUTION: A heat curable resin composition for encapsulation is used for encapsulating gaps between a substance and a semiconductor chip mounted on the substrate in a face-down manner. The heat curable resin composition for encapsulation has an acryl resin which has at least one of five-membered ring and six-membered ring and is liquid at 25°C and an inorganic filler having maximum particle diameter of 10.0 μm or less. The acryl resin is in a range of 10 to 40 mass% and the inorganic filler is in a range of 60 to 90 mass% based on total amount of the acryl resin and the inorganic filler. The heat curable resin composition for encapsulation further contains organic peroxide having 1 min half-life temperature in a range of 120 to 190°C.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermosetting resin composition for sealing, a method for manufacturing a semiconductor device, and a semiconductor device, and more particularly, a sealing suitable for sealing between a substrate and a semiconductor chip by underfilling using a pre-feed method. A thermosetting resin composition for fastening, a method for producing a semiconductor device for sealing between a base material and a semiconductor chip by a pre-feeding underfill using the thermosetting resin composition for sealing, and this sealing The present invention relates to a semiconductor device sealed by underfilling using a thermosetting resin composition for stopping.

  When the flip chip type semiconductor chip 3 is mounted face-down on a base material, for example, an FC-BGA (Flip Chip Ball Ball Array) is conventionally used as the semiconductor chip 3. The distance between the bump electrodes 33 in the FC-BGA is 150 μm or more (see FIG. 4B). An underfilling technique for sealing the gap by mounting the semiconductor chip 3 on the base material and then filling the gap between the base material and the semiconductor chip 3 with a resin composition is widely adopted.

  In recent years, there has been a demand for a narrow pitch between the bump electrodes 33 in the semiconductor chip 3 for high integration of electronic components. Therefore, as the semiconductor chip 3, an FC-CSP (flip chip-chip size package) as shown in FIG. 4A has been proposed. The bump electrode 33 in the semiconductor chip 3 shown in FIG. 4A is composed of a copper pillar 31 and a solder bump 32 provided at the tip thereof. Thereby, the pitch between the bump electrodes 33 can be set to 100 μm or less, for example, 50 μm. In addition, when the pillar 31 is made of copper, it is possible to increase the energization amount of the bump electrode 33 and to improve the thermal conductivity of the bump electrode 33. Further, since the bump electrode 33 includes the pillar 31, the amount of the solder bump 32 in the bump electrode 33 can be suppressed. Furthermore, since the pillar 31 does not melt during the reflow process, it is possible to suppress a short circuit due to the spread of the solder.

  Along with the narrow pitch of the bump electrodes, the pre-feed method is attracting attention as an underfilling technique. In this prior supply method, for example, a base material provided with conductor wiring, a semiconductor chip provided with bump electrodes, and a thermosetting resin composition for sealing that is liquid at room temperature are prepared. Subsequently, the thermosetting resin composition for sealing is disposed on the base material, the semiconductor chip is disposed at the position where the thermosetting resin composition for sealing on the base material is disposed, and on the conductor wiring A bump electrode is disposed on the surface. In this state, by heating the sealing thermosetting resin composition and the bump electrode, the sealing thermosetting resin composition is cured to form a sealing material, and the bump electrode and the conductor wiring are electrically connected. Connect. Thereby, the mounting of the semiconductor chip on the base material and the sealing of the gap between the semiconductor chip and the base material can be performed simultaneously. Moreover, even if the pitch between the bump electrodes is narrow, the sealing material is not easily filled in the gap between the semiconductor chip and the substrate.

  In the case of sealing by the first supply method, an acrylic resin is added to the sealing thermosetting resin composition in order to suppress voids in the sealing material, and the thermal conductivity of the sealing material is improved. For example, an inorganic filler is included (see Patent Document 1).

JP 2011-243786 A

  In recent years, the thermosetting resin composition for sealing has been requested not only to improve the fluidity at the time of molding along with the narrowing of the pitch of the bump electrodes, but also to improve the curing speed for cost reduction, As the amount of heat generated by the semiconductor chip increases, there is a demand for improving the heat resistance of the cured product. Furthermore, it is also required to suppress conduction failure due to the presence of inorganic filler particles between the bump electrode of the semiconductor chip and the conductor wiring of the base material.

  However, a sealing thermosetting resin composition that sufficiently satisfies these requirements has not been obtained.

  The present invention has been made in view of the above-mentioned reasons, and is suitable for sealing between a base material and a semiconductor chip by a pre-feeding type underfilling, has high fluidity, and is cured when heated. Thermosetting resin composition for sealing, which has a high speed, has high heat resistance of the cured product, and can suppress poor conduction between the bump electrode of the semiconductor chip and the conductor wiring of the base material, and for sealing It is an object of the present invention to provide a semiconductor device manufacturing method using a thermosetting resin composition and a semiconductor device including a sealing material made of a cured product of the sealing thermosetting resin composition.

  The thermosetting resin composition for sealing according to one embodiment of the present invention is a thermosetting resin for sealing for sealing a gap between a substrate and a semiconductor chip mounted face-down on the substrate. An acrylic resin that has at least one of a five-membered ring and a six-membered ring and is liquid at 25 ° C., and an inorganic filler having a maximum particle size of 10.0 μm or less, The acrylic resin is in the range of 10 to 40% by mass, the inorganic filler is in the range of 60 to 90% by mass, and the 1 minute half-life temperature is 120 to 190 with respect to the total amount of the acrylic resin and the inorganic filler. It further contains an organic peroxide in the range of ° C.

  The manufacturing method of the semiconductor device which concerns on 1 aspect of this invention arrange | positions the said thermosetting resin composition for sealing on the base material provided with a conductor wiring, The said thermosetting resin composition for sealing on the said base material A semiconductor chip including a bump electrode is disposed face down at a position where an object is disposed, the bump electrode is disposed on the conductor wiring, and the sealing thermosetting resin composition and the bump electrode Heat-treating the sealing thermosetting resin composition to form a sealing material and melting the bump electrode to electrically connect the bump electrode and the conductor wiring including.

  A semiconductor device according to one embodiment of the present invention includes a base material, a semiconductor chip mounted face-down on the base material, and a sealing material that seals between the base material and the semiconductor chip. The sealing material is made of a cured product of the sealing thermosetting resin composition.

  According to one aspect of the present invention, it is suitable for sealing between a base material and a semiconductor chip by a pre-feeding type underfilling, has high fluidity during molding, and has a curing rate when heated. A thermosetting resin composition for sealing that is fast and has high heat resistance of the cured product is obtained.

Each of FIG. 1A to FIG. 1D is a schematic cross-sectional view showing a process of manufacturing a semiconductor device in one embodiment of the present invention. 2A is a cross-sectional photograph showing the connection part between the bump electrode and the electrode pad showing the result of the solder wettability evaluation test of Example 4, and FIG. 2B shows the result of the solder wettability evaluation test of Example 3. FIG. 2C is a cross-sectional photograph showing the connection part between the bump electrode and the electrode pad showing the result of the solder wettability evaluation test of Comparative Example 6. FIG. 3A is a cross-sectional photograph showing the connection part between the bump electrode and the electrode pad showing the result of the filler penetration test of Example 5, and FIG. 3B is the bump electrode showing the result of the filler penetration test of Comparative Example 6 3C is a cross-sectional photograph showing the connection part between the bump electrode and the electrode pad showing the result of the filler penetration test of Comparative Example 7. FIG. Each of FIG. 4A and FIG. 4B is a perspective view showing an example of a semiconductor chip.

  The sealing thermosetting resin composition according to this embodiment will be described.

  When the thermosetting resin composition for sealing according to the present embodiment is used to manufacture the semiconductor device 1, the sealing material 42 is provided in the gap between the base material 2 and the semiconductor chip 3 by the underfilling of the first supply method. Suitable for forming (see FIGS. 1A-1D).

  The sealing thermosetting resin composition according to this embodiment is preferably liquid at normal temperature. “Liquid at normal temperature” means having fluidity at 25 ° C. under atmospheric pressure. In particular, the thermosetting resin composition for sealing preferably has fluidity at any temperature within the range of 20 to 30 ° C. under atmospheric pressure.

  The thermosetting resin composition for sealing contains at least one of a five-membered ring and a six-membered ring, and contains an acrylic resin that is liquid at 25 ° C. and an inorganic filler having a maximum particle size of 10.0 μm or less. To do. An acrylic resin exists in the range of 10-40 mass% with respect to the total amount of an acrylic resin and an inorganic filler, and an inorganic filler exists in the range of 60-90 mass%. The thermosetting resin composition for sealing further contains an organic peroxide having a half-life temperature of 120 to 190 ° C. for 1 minute.

  In this embodiment, since the acrylic resin is liquid at 25 ° C., the thermosetting resin composition for sealing has excellent fluidity at the time of molding. Moreover, since the acrylic resin has at least one of a five-membered ring and a six-membered ring, the cured product of the acrylic resin has a high glass transition temperature and a high thermal decomposition temperature. For this reason, the sealing material 42 has high heat resistance.

  Further, since the maximum particle size of the inorganic filler is 10 μm or less, the particles of the inorganic filler are easily dispersed well in the sealing material 42. For this reason, the bump wiring 33 provided in the semiconductor chip 3 and the conductor wiring provided in the substrate 2 Inorganic filler particles are less likely to intervene between 21 and 21. Further, even if inorganic filler particles are interposed between the bump electrode 33 and the conductor wiring 21, since the maximum particle size of the inorganic filler is small, poor conduction between the bump electrode 33 and the conductor wiring 21 occurs. Hateful. The inorganic filler preferably has a thermal conductivity of 20 W / m · K or more.

  Moreover, the sealing which has high heat conductivity is because the acrylic resin is in the range of 10 to 40% by mass and the inorganic filler is in the range of 60 to 90% by mass with respect to the total amount of the acrylic resin and the inorganic filler. The stopper 42 can be obtained, and the sealing member 42 having a thermal conductivity of 1 W / m · K can be obtained. Furthermore, the fast curing rate of the thermosetting resin composition for sealing can be maintained, so that voids in the sealing material 42 can be effectively suppressed.

  Furthermore, since the one-minute half-life temperature of the organic peroxide is within the range of 120 to 190 ° C., when the thermosetting resin composition for sealing is heated, the organic peroxide is quickly decomposed to generate radicals. Arise. For this reason, the curing rate of the thermosetting resin composition for sealing is high. For this reason, the manufacturing efficiency of the semiconductor device 1 can be improved.

  The constituent components of the thermosetting resin composition for sealing will be described in more detail.

  The acrylic resin has thermosetting properties and is liquid at 25 ° C. In particular, the acrylic resin preferably has fluidity at any temperature within the range of 20 to 30 ° C. under atmospheric pressure. When the sealing thermosetting resin composition contains an acrylic resin, voids are less likely to occur in the sealing material 42 formed from the sealing thermosetting resin composition. This is considered to be because the thermosetting resin composition for sealing thickens at the initial stage when the acrylic resin is cured by radical polymerization reaction.

  As described above, the acrylic resin has at least one of a five-membered ring and a six-membered ring. Examples of the five-membered ring include a cyclopentane ring, a cyclopentene ring, and a cyclopentadiene ring. The acrylic resin may have one five-membered ring per molecule or may have a plurality of five-membered rings. Examples of the six-membered ring include a cyclohexane ring, a cyclohexene ring, a cyclohexadiene ring, and a benzene ring. The acrylic resin may have one six-membered ring per molecule or may have a plurality of six-membered rings. The acrylic resin may have at least one 5-membered ring and at least one 6-membered ring per molecule. Further, the 5-membered ring and the 6-membered ring may be part of a condensed polycyclic structure such as a naphthalene ring, or may be part of a bridged polycyclic structure such as tricyclodecane or adamantane. The 5-membered ring and the 6-membered ring need not be limited to an aromatic ring or an unsaturated ring. The reason for this is not limited to aromatic rings and unsaturated rings, but the acrylic resin has at least one of a five-membered ring and a six-membered ring, thereby giving a high glass transition temperature to the cured product of the acrylic resin, It is because the heat resistance excellent in 42 can be provided. That is, when there is no 5-membered ring or 6-membered ring, the glass transition temperature of the cured acrylic resin is low, and the heat resistance of the sealing material 42 is reduced.

  As described above, when the acrylic resin has at least one of the five-membered ring and the six-membered ring, the glass transition temperature and the thermal decomposition temperature of the cured acrylic resin are increased, and the heat resistance of the sealing material 42 is improved. For this reason, even when the amount of heat generated by the semiconductor chip 3 is large and when the semiconductor device 1 is used in a high temperature environment, the semiconductor device 1 has high reliability.

  The weight average molecular weight of the acrylic resin is preferably in the range of 100-1500. If the weight average molecular weight is 100 or more, since the curability of the acrylic resin is particularly good, a cured product having particularly high strength and heat resistance can be obtained. If the weight average molecular weight is 1500 or less, the acrylic resin can be prevented from becoming highly viscous or rubbery, and the acrylic resin is easy to handle. Therefore, when the weight average molecular weight of the acrylic resin is in the range of 100 to 1500, the strength and heat resistance of the cured product of the acrylic resin can be particularly increased, and the viscosity of the acrylic resin can be lowered to improve the handleability. The weight average molecular weight can be measured by general GPC (gel permeation chromatography).

  In order to ensure the heat resistance of the sealing material 42, the acrylic resin preferably contains a compound having two or more (meth) acryloyl groups per molecule, and 2 to 6 (meth) per molecule. It is more preferable to include a compound having an acryloyl group, and it is even more preferable to include a compound having two (meth) acryloyl groups per molecule.

  Examples of compounds having two (meth) acryloyl groups per molecule are dimethylol tricyclodecane di (meth) acrylate, cyclohexanediol di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, cyclohexanediethanoldi ( (Meth) acrylate, cyclohexanedialkyl alcohol di (meth) acrylate, and dimethanoltricyclodecane di (meth) acrylate.

  Examples of compounds having two (meth) acryloyl groups per molecule are the reaction product of 1 mol of bisphenol A, bisphenol F or bisphenol AD and 2 mol of glycidyl acrylate, and 1 mol of bisphenol A, bisphenol F or bisphenol AD and glycidyl methacrylate. Also includes reactants with 2 moles.

  Examples of compounds having two or more (meth) acryloyl groups per molecule include (meth) acrylates having a crosslinked polycyclic structure. Specifically, examples of the compound having two or more (meth) acryloyl groups per molecule include a compound represented by the following formula (I) and a compound represented by the following formula (II). These compounds can particularly improve the heat resistance of the sealing material 42.

In formula (I), each of R ¹ and R ² represents a hydrogen atom or a methyl group, a is 1 or 2, and b is 0 or 1.

In formula (II), each of R ³ and R ⁴ represents a hydrogen atom or a methyl group, X represents a hydrogen atom, a methyl group, a methylol group, an amino group, or a (meth) acryloyloxymethyl group, and c represents 0 Or it is 1.

More specific examples of the (meth) acrylate having a bridged polycyclic structure include (meth) acrylate having a dicyclopentadiene skeleton in which a in formula (I) is 1 and b is 0, and c in formula (II) Is a (meth) acrylate having a perhydro-1,4: 5,8-dimethananaphthalene skeleton in which 1 is 1, a (meth) acrylate having a norbornane skeleton in which c in formula (II) is 0, R in formula (I) ¹ and R ² are hydrogen atoms, a = 1, b = 0 tricyclodecane dimethanol diacrylate (dicyclopentadienyl diacrylate), X in formula (II) is an acryloyloxymethyl group, R ³ and R Perhydro-1,4: 5,8-dimethananaphthalene-2,3,7-trimethylol triacrylate, wherein ⁴ is a hydrogen atom and c is 1, X in formula (II) , R ³ and R ⁴ are hydrogen atoms, norbornane dimethylol diacrylate in which c is 0, and perhydro-1,4: 5 in which X, R ³ and R ⁴ in formula (II) are hydrogen atoms, and c is 1 , 8-dimethananaphthalene-2,3-dimethylol diacrylate. In particular, the (meth) acrylate having a crosslinked polycyclic structure preferably contains at least one of tricyclodecane dimethanol diacrylate and norbornane dimethylol diacrylate.

  Examples of commercially available products of tricyclodecane dimethanol diacrylate include A-DCP manufactured by Shin-Nakamura Chemical Co., Ltd., Light acrylate DCP-A manufactured by Kyoeisha Co., Ltd., and FA-513M manufactured by Hitachi Chemical.

  Examples of the compound having two or more (meth) acryloyl groups include di (meth) acrylate having a structure in which an alkylene oxide is added to a bisphenol skeleton. Specifically, examples of the compound having two or more (meth) acryloyl groups include a compound represented by the formula (III) and a compound represented by the formula (IV). These compounds can improve the adhesion between the sealing material 42, the semiconductor chip 3 and the substrate 2.

In formula (III), R ⁵ represents hydrogen, a methyl group, or an ethyl group, R ⁶ represents a divalent organic group, and each of m and n represents an integer of 1 to 20.

In Formula (IV), R ⁵ represents hydrogen, a methyl group, or an ethyl group, R ⁶ represents a divalent organic group, and each of m and n represents an integer of 1 to 20.

  More specific examples of di (meth) acrylate having a structure in which an alkylene oxide is added to a bisphenol skeleton are Aronix M-210, M-211B (manufactured by Toagosei), NK ester ABE-300, A-BPE- 4, A-BPE-6, A-BPE-10, A-BPE-20, A-BPE-30, BPE-100, BPE-200, BPE-500, BPE-900, BPE-1300N (made by Shin-Nakamura Chemical) EO modified bisphenol A type di (meth) acrylate (n = 2-20); EO modified bisphenol F type di (meth) acrylate (n = 2-20) such as Aronix M-208 (manufactured by Toagosei); PO-modified bisphenol such as acrylate DA-250 (manufactured by Nagase Kasei) and biscoat 540 (manufactured by Osaka Organic Chemical Industry) A-type di (meth) acrylate (n = 2 to 20); and PO-modified phthalic diacrylate such as Denacol acrylate DA-721 (manufactured by Nagase Kasei).

  The compound having two or more (meth) acryloyl groups is preferably epoxy (meth) acrylate. In this case, particularly when the thermosetting resin composition for sealing contains an epoxy resin, the reactivity of the thermosetting resin composition for sealing is improved and the heat resistance and adhesion of the sealing material 42 are improved. improves.

  Epoxy (meth) acrylate is, for example, an oligomer that is an addition reaction product of an epoxy resin and an unsaturated monobasic acid such as acrylic acid or methacrylic acid.

  The epoxy resin that is a raw material of the epoxy (meth) acrylate includes a diglycidyl compound (bisphenol type epoxy resin) obtained by condensation of bisphenols typified by bisphenol such as bisphenol A and bisphenol F and epihalohydrin. The epoxy resin may include an epoxy resin having a phenol skeleton. As an epoxy resin having a phenol skeleton, a polyvalent glycidyl ether (phenol novolac type epoxy resin, cresol novolak type) obtained by the condensation of phenol or cresol and phenol novolaks which are condensates of aldehydes typified by formalin and epihalohydrin. Epoxy resin). The epoxy resin may include an epoxy resin having a cyclohexyl ring.

  The epoxy (meth) acrylate preferably contains, for example, bisphenol A type epoxy acrylate that is liquid at 25 ° C. The bisphenol A type epoxy acrylate is represented by the following formula (V), for example.

  In the formula (V), n represents a positive integer.

  Examples of commercially available products of bisphenol A type epoxy acrylate include Denacol acrylate DA-250 (manufactured by Nagase Kasei, 60 Pa · s at 25 ° C.), Denacol acrylate DA-721 (manufactured by Nagase Kasei, 100 Pa · s at 25 ° C.), Lipoxy VR-77 (manufactured by Showa Polymer Co., Ltd., 100 Pa · s at 25 ° C.), lipoxy VR-90 (manufactured by Showa Polymer Co., Ltd.), and epoxy ester 3002M (N) (manufactured by Kyoeisha Chemical Co., Ltd.) are included.

  When the acrylic resin contains a compound having 3 or more (meth) acryloyl groups, examples of the compound having 3 or more (meth) acryloyl groups are 1,3-adamantanediol dimethacrylate, 1,3-adamantanediol Diacrylate, 1,3-adamantane dimethanol dimethacrylate, and 1,3-adamantane dimethanol diacrylate are included.

  The acrylic resin is, for example, a (meth) acrylate having a crosslinked polycyclic structure of 10 to 50% by mass, a di (meth) acrylate having a structure in which an alkylene oxide is added to a 3 to 20% by mass of a bisphenol skeleton, and 5 to 30 Mass% epoxy (meth) acrylate may be included.

  The thermosetting resin composition for sealing may contain a second acrylic resin having neither a five-membered ring nor a six-membered ring. The second acrylic resin is preferably 10% by mass or less based on the total of the acrylic resin and the second acrylic resin.

  The organic peroxide in the thermosetting resin composition for sealing is a radical initiator. The one minute half-life temperature of the organic peroxide is in the range of 120-190 ° C. For this reason, the curing rate of the thermosetting resin composition for sealing is high as described above, and thus the manufacturing efficiency of the semiconductor device 1 can be improved. Moreover, peeling between the semiconductor chip 3 and the sealing material 42 can be suppressed because the curing reaction proceeds sufficiently fast. Furthermore, the thermosetting resin composition for sealing is quickly produced to such an extent that the wettability between the bump electrode 33 made of solder and the conductor wiring 21 is not hindered in the initial stage in the step of heat-curing the thermosetting resin composition for sealing. By increasing the viscosity, generation of voids in the sealing material 42 is suppressed. More preferably, the one-minute half-life temperature of the organic peroxide is in the range of 150 to 190 ° C.

  Organic peroxides include, for example, t-butyl peroxy-2-ethylhexyl monocarbonate (1 minute half-life temperature 161.4 ° C.), t-butyl peroxybenzoate (1 minute half-life temperature 166.8 ° C.), t- Butylcumyl peroxide (1 minute half-life temperature 173.3 ° C), Dicumyl peroxide (1 minute half-life temperature 175.2 ° C), α, α'-di (t-butylperoxy) diisopropylbenzene (1 minute Half-life temperature 175.4 ° C.), 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (1 minute half-life temperature 179.8 ° C.), and di-t-butyl peroxide (1 At least one component selected from the group consisting of a minute half-life temperature of 185.9 ° C.).

  The organic peroxide is preferably in the range of 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the acrylic resin. In this case, particularly when the gap between the base material 2 and the semiconductor chip 3 is sealed by the underfilling of the pre-feed method, the particularly good gap between the bump electrode 33 of the semiconductor chip 3 and the conductor wiring 21 of the base material 2 is obtained. Can secure wettability. That is, when the organic peroxide is 2.0 parts by mass or less, the curing rate of the thermosetting resin composition for sealing can be moderately suppressed, so that the thermosetting resin composition for sealing on the substrate 2 is used. When the semiconductor chip 3 is disposed face down on the base material 2 in a state where the bump electrode 33 is heated and bonded to the conductor wiring 21 in this state, the thermosetting resin composition for sealing is used. It is possible to prevent the solder of the bump electrode 33 from becoming difficult to flow due to the increase in the viscosity of the solder. Therefore, the connection reliability between the bump electrode 33 and the conductor wiring 21 can be improved. Moreover, favorable sclerosis | hardenability of the thermosetting resin composition for sealing can be ensured as an organic peroxide is 0.2 or more.

  The thermosetting resin composition for sealing contains an inorganic filler. For this reason, the thermal expansion coefficient of the sealing material 42 can be adjusted. Further, the thermal conductivity of the sealing material 42 is improved by the inorganic filler, so that the heat generated from the semiconductor chip 3 can be efficiently released through the sealing material 42.

  The inorganic filler desirably contains at least one material selected from the group consisting of aluminum nitride, alumina, boron nitride, and silicon carbide. This is because aluminum nitride, alumina, boron nitride and silicon carbide have high thermal conductivity. In addition to the aluminum nitride, alumina, boron nitride, and silicon carbide, it is also useful to add other inorganic fillers as the inorganic filler.

  The inorganic filler is at least one material selected from the group consisting of aluminum nitride, alumina, boron nitride and silicon carbide, silica powder such as fused silica, synthetic silica and crystalline silica; oxide such as titanium oxide; talc and calcined Silicates such as clay, unfired clay, mica and glass; carbonates such as calcium carbonate, magnesium carbonate and hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide; barium sulfate, calcium sulfate and sulfurous acid At least one selected from the group consisting of sulfates or sulfites such as calcium; borates such as zinc borate, barium metaborate, aluminum borate, calcium borate, sodium borate; and nitrides such as boron nitride and silicon nitride The materials may contain. Depending on the application, the inorganic filler may be a silica powder such as fused silica, synthetic silica or crystalline silica; an oxide such as alumina or titanium oxide; a silicate such as talc, calcined clay, unfired clay, mica or glass; calcium carbonate or carbonic acid. Carbonates such as magnesium and hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide; sulfates or sulfites such as barium sulfate, calcium sulfate and calcium sulfite; zinc borate, barium metaborate and boric acid It is also possible to contain mainly at least one material selected from the group consisting of borates such as aluminum, calcium borate and sodium borate; and nitrides such as boron nitride and silicon nitride.

  The inorganic filler is preferably subjected to a coupling treatment. In this case, the fluidity of the thermosetting resin composition for sealing can be reduced by reducing the viscosity. Therefore, particularly when the space between the base material 2 and the semiconductor chip 3 is sealed by the underfilling of the first supply method, particularly good wetting between the bump electrode 33 of the semiconductor chip 3 and the conductor wiring 21 of the base material 2 is achieved. Can be secured. That is, when the sealing thermosetting resin composition has high fluidity due to the coupling treatment of the inorganic filler, the sealing thermosetting resin composition is disposed on the substrate 2. When the semiconductor chip 3 is arranged face down on the substrate 2 and the bump electrode 33 is heated and joined to the conductor wiring 21 in this state, the bump electrode is increased by the increase in the viscosity of the thermosetting resin composition for sealing. It is possible to prevent the solder 33 from becoming difficult to flow, and it is particularly difficult for the inorganic filler particles to intervene between the bump electrode 33 and the conductor wiring 21. Furthermore, when the inorganic filler is subjected to coupling treatment, voids in the sealing material 42 can be reduced. This is thought to be because voids are less likely to be mixed into the sealing thermosetting resin composition by reducing the viscosity of the sealing thermosetting resin composition.

  The coupling treatment is performed by treating the surface of the inorganic filler with a coupling agent. The coupling agent can contain, for example, at least one component selected from the group consisting of silane coupling agents, higher fatty acids, higher fatty acid esters, higher fatty acid amides, and phosphate esters. In particular, when the inorganic filler contains aluminum nitride, the coupling agent is preferably a phosphate ester. When the inorganic filler contains alumina, the coupling agent is preferably a silane coupling agent.

  The thermal conductivity of the inorganic filler is preferably 20 W / m · K or more. In this case, the thermal conductivity of the sealing material 42 can be particularly improved, and the heat dissipation of the semiconductor chip 3 by the sealing material 42 can be improved. For this purpose, the inorganic filler preferably contains at least one material selected from the group consisting of aluminum nitride, alumina, boron nitride and silicon carbide having a thermal conductivity of 20 W / m · K or more.

  The shape of the inorganic filler may be crushed, acicular, scaly, or spherical, and is not particularly limited. However, the inorganic filler is improved in dispersibility in the thermosetting resin composition for sealing, and for sealing. In order to control the viscosity of the thermosetting resin composition, the inorganic filler is preferably spherical.

  The inorganic filler preferably has an average particle size smaller than the dimension between the substrate 2 and the semiconductor chip 3 mounted thereon.

  When the maximum particle size of the inorganic filler is 10 μm or less, the particles of the inorganic filler are easily dispersed well in the sealing material 42 as described above. For this reason, it becomes difficult for the inorganic filler particles to intervene between the bump electrode 33 of the semiconductor chip 3 and the conductor wiring 21 of the substrate 2. Further, even if inorganic filler particles are interposed between the bump electrode 33 and the conductor wiring 21, since the maximum particle size of the inorganic filler is small, poor conduction between the bump electrode 33 and the conductor wiring 21 occurs. Hateful. It is particularly preferable if the maximum particle size of the inorganic filler is 5 μm or less.

  It is particularly preferred if the average particle size of the inorganic filler is in the range of 0.1 to 10.0 μm. In this case, even when the interval between the adjacent bump electrodes 33 is narrow, when the gap between the base material 2 and the semiconductor chip 3 is sealed by the pre-feeding underfilling, the bump electrode 33 and the base material 2 of the semiconductor chip 3 are sealed. Particularly good wettability with the conductor wiring 21 can be ensured. That is, when the average particle diameter of the inorganic filler is 10.0 μm or less, the thermosetting resin composition for sealing can have good fluidity, and therefore the thermosetting resin composition for sealing on the substrate 2. When the semiconductor chip 3 is arranged face down on the base material 2 in the state where the object is arranged, and the bump electrode 33 is heated and joined to the conductor wiring 21 in this state, the thermosetting resin composition for sealing It is possible to suppress the solder of the bump electrode 33 from becoming difficult to flow due to an increase in the viscosity of the object, and it is particularly difficult for inorganic filler particles to intervene between the bump electrode 33 and the conductor wiring 21. For this reason, the connection reliability between the bump electrode 33 and the conductor wiring 21 can be improved. Moreover, the viscosity rise of the thermosetting resin composition for sealing can also be suppressed when the average particle diameter of the inorganic filler is 0.1 μm or more.

  Furthermore, the average particle size of the inorganic filler is in the range of 0.5 to 4.0 μm, so that the thermosetting resin composition for sealing and the filling density of the inorganic filler in the sealing material 42 are improved, and the sealing is performed. It is preferable for adjusting the viscosity of the thermosetting resin composition.

  In addition, the maximum particle size in this embodiment is calculated | required from the result of the particle size distribution measurement by a laser beam diffraction method. Moreover, the average particle diameter in this embodiment is a median diameter calculated from the result of the particle size distribution measurement by a laser beam diffraction method.

  In order to adjust the viscosity of the thermosetting resin composition for sealing or the physical properties of the sealing material 42, the inorganic filler may contain two or more components having different average particle diameters.

  The thermosetting resin composition for sealing preferably contains a flux (also referred to as an activator). In this case, due to the action of the flux, the oxide film on the surface of the solder in the semiconductor chip 3 is removed during reflow, and the electrical connection reliability between the semiconductor chip 3 and the substrate 2 is improved.

  The boiling point of the flux is preferably around 220 ° C, particularly preferably 180 ° C or higher. The melting point of the flux is preferably around 220 ° C. or lower, and particularly preferably 180 ° C. or lower. In this case, when the thermosetting resin composition for sealing is subjected to heat treatment and cured, the flux is liquid and difficult to be released from the sealing thermosetting resin composition. Can be demonstrated.

  The flux contains, for example, at least one component selected from the group consisting of organic acids, various amines, and salts thereof. In particular, the flux preferably contains an organic acid. In this case, the wettability between the bump electrode 33 and the conductor wiring 21 can be particularly improved.

  Organic acids include, for example, abietic acid, glutaric acid, succinic acid, malonic acid, oxalic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, diglycolic acid, thiodiglycolic acid, phthalic acid, isophthalic acid, terephthalic acid And at least one compound selected from the group consisting of propanetricarboxylic acid, citric acid, and tartaric acid. In particular, in order to particularly improve the wettability between the bump electrode 33 and the conductor wiring 21, the organic acid may contain at least one component selected from the group consisting of adipic acid, sebacic acid, glutaric acid and benzoic acid. preferable.

  The flux is preferably in the range of 0.1 to 20% by mass and more preferably in the range of 1 to 10% by mass with respect to the entire thermosetting resin composition for sealing. In this case, since the activity of the flux is particularly high, the wettability between the solder and the conductor wiring 21 is particularly high. Furthermore, it can suppress that the flux makes the sealing material 42 fragile or impairs the insulation reliability of the sealing material 42, and the bleeding of the flux from the sealing material 42 can also be suppressed.

  The thermosetting resin composition for sealing may contain additives other than the above components as long as the effects of the present invention are not impaired. Examples of the additive include a silane coupling agent, an antifoaming agent, a leveling agent, a low stress agent, and a pigment. However, the thermosetting resin composition for sealing preferably contains no solvent.

  The thermosetting resin composition for sealing is prepared, for example, by the following method.

  First, a mixture is obtained by blending components other than the inorganic filler of the thermosetting resin composition for sealing simultaneously or separately. The mixture is agitated and mixed while performing heat treatment or cooling treatment as necessary. Next, an inorganic filler is added to the mixture. The inorganic filler is treated with a silane coupling agent before being added to the mixture. Next, the mixture is stirred and mixed again while performing heat treatment or cooling treatment as necessary. Thereby, the thermosetting resin composition for sealing can be obtained. In order to stir the mixture, for example, a disper, a planetary mixer, a ball mill, a three roll, etc. can be used in combination.

  In this embodiment, it is preferable that the viscosity of the thermosetting resin composition for sealing measured with a B-type rotational viscometer at 25 ° C. and a rotational speed of 50 rpm is 200 Pa · s or less. In this case, the filling property of the thermosetting resin composition for sealing into a fine space can be improved. The viscosity is more preferably 100 Pa · s or less, and further preferably 60 Pa · s or less. The viscosity is preferably 1 Pa · s or more, more preferably 3 Pa · s or more, and even more preferably 5 Pa · s or more. In this case, when the sealing thermosetting resin composition is applied onto the substrate 2, the shape of the sealing thermosetting resin composition can be stably maintained on the substrate 2. Moreover, workability | operativity at the time of arrange | positioning the thermosetting resin composition for sealing on the base material 2 becomes it especially favorable that a viscosity exists in the range of 1-200 Pa * s. It is also preferable that the viscosity is in the range of 5 to 100 Pa · s. It is particularly preferable if the viscosity is in the range of 5 to 60 Pa · s.

  Viscosity when the rotational speed at the time of measurement is changed to 5 rpm, that is, using a B-type rotational viscometer, the viscosity of the thermosetting resin composition for sealing measured at 25 ° C. under the rotational speed of 5 rpm is 15 It is also preferable to be within a range of ˜600 Pa · s. Thus, when the viscosity or rheology of the thermosetting resin composition for sealing is adjusted so that the viscosity measured at a rotational speed of 5 rpm is 2 to 4 times the viscosity measured at a rotational speed of 50 rpm, Especially the applicability | paintability of the thermosetting resin composition for sealing becomes high.

  It is preferable that the thermosetting resin composition for sealing has a property of being cured within 10 seconds from the start of heating by being heated at any temperature within a range of 220 to 280 ° C. In this case, it is possible to shorten the heat treatment time when the sealing thermosetting resin composition is heat-treated to produce the sealing material 42, and thus the production efficiency of the semiconductor device 1 is increased. Whether or not the thermosetting resin composition for sealing is cured can be confirmed by differential scanning calorimetry. As a result of differential scanning calorimetry, when no exothermic peak is observed at a temperature at which the curing reaction of the sealing thermosetting resin composition proceeds, it can be determined that the sealing thermosetting resin composition is cured. . As above-mentioned, in this embodiment, since the 1 minute half-life temperature contains the organic peroxide which exists in the range of 120-190 degreeC, the cure rate of the thermosetting resin composition for sealing is quick. For this reason, the said characteristic can be easily achieved by adjusting suitably the composition of the thermosetting resin composition for sealing in the range of the said description.

  The viscosity of the sealing thermosetting resin composition as described above can be realized by adjusting the composition of the sealing thermosetting resin composition within the range described above.

  It is preferable that the thermal conductivity of the sealing material 42 obtained by thermosetting the thermosetting resin composition for sealing is 1.0 W / m · K or more. In this case, the heat dissipation of the semiconductor device 1 including the sealing material 42 is particularly high. Such a high thermal conductivity can be realized by adjusting the composition of the thermosetting resin composition for sealing within the range of the above description. The higher the thermal conductivity of the sealing material 42, the higher the heat dissipation of the semiconductor device 1. However, when the content of the inorganic filler is increased for improving the thermal conductivity, the viscosity of the thermosetting resin composition for sealing becomes too high, for example, exceeding 200 Pa · s, so that the thermosetting resin for sealing The applicability of the composition may be affected. In order to improve the thermal conductivity while suppressing the increase in viscosity, a special material such as diamond powder is required. For this reason, it is preferable that the thermal conductivity of the sealing material 42 is 10 W / m · K or less.

  The thermosetting resin composition for sealing is suitable as an underfill or NCP (Non Conductive Polymer). An example of a method of obtaining the semiconductor device 1 by sealing between the base material 2 and the semiconductor chip 3 by underfilling of a first supply method (also referred to as a thermocompression bonding method) using a thermosetting resin composition for sealing. Will be described with reference to FIGS. 1A to 1D.

  The base material 2 is, for example, a mother board, a package board, or an interposer board. For example, the base material 2 includes an insulating substrate made of glass epoxy, polyimide, polyester, ceramic, or the like, and a conductor wiring 21 formed on the surface thereof. The conductor wiring 21 is made of copper, for example. The conductor wiring 21 includes, for example, an electrode pad 22.

  The semiconductor chip 3 is a flip chip type chip such as a BGA (ball grid array), an LGA (land grid array), or a CSP (chip size package). Further, the semiconductor chip 3 may be a PoP (package on package) type chip. The semiconductor chip 3 includes a bump electrode 33 on the surface facing the substrate 2. The bump electrode 33 includes, for example, a copper pillar 31 (also referred to as a copper pillar) and a solder bump 32 provided at the tip of the pillar 31. The solder bumps 32 are, for example, Sn-3.5Ag (melting point 221 ° C.), Sn-2.5Ag-0.5Cu-1Bi (melting point 214 ° C.), Sn-0.7Cu (melting point 227 ° C.), Sn-3Ag-0. It is made of lead-free solder having a melting point of 210 ° C. or higher, such as 0.5 Cu (melting point: 217 ° C.).

  In the present embodiment, the pitch between adjacent bump electrodes 33 is preferably 100 μm or less, more preferably 70 μm or less, and even more preferably 50 μm or less. In this case, it is possible to cope with high integration of electronic components. The pitch between adjacent bump electrodes 33 is, for example, 30 μm or more, but is not limited thereto.

  In this embodiment, since the thermosetting resin composition for sealing has good fluidity, the pitch of the bump electrodes 33 can be reduced. For example, the shortest pitch between the bump electrodes 33 may be in the range of 5 to 150 μm. Even in this case, when the bump electrode 33 is heated and joined to the conductor wiring 21, the inhibition of the solder flow of the bump electrode 33 by the sealing thermosetting resin composition can be suppressed. The connection reliability with the wiring 21 can be improved.

  In the present embodiment, the diameter of the bump electrode 33 is in the range of 3 to 90 μm, for example. Even when the bump electrode 33 has such a diameter, when the bump electrode 33 is heated and joined to the conductor wiring 21, inhibition of the solder flow of the bump electrode 33 by the sealing thermosetting resin composition is suppressed. In addition, it is possible to suppress the presence of inorganic filler particles between the bump electrode 33 of the semiconductor chip 3 and the conductor wiring 21 of the base material 2. For this reason, the connection reliability between the bump electrode 33 and the conductor wiring 21 can be suppressed. Can be improved.

  In this method, the semiconductor chip 3 can be mounted face-down on the substrate 2 using a flip chip bonder 50 including a bonding head 51 and a stage 52.

  In this method, first, as shown in FIG. 1A, a sealing thermosetting resin composition is disposed as an underfill 41 on the surface of the substrate 2 that includes the conductor wiring 21. Examples of the method for disposing the thermosetting resin composition for sealing include a method using a dispenser, a screen printing method, and an ink jet method. In addition, what is necessary is just to optimize suitably the quantity of the thermosetting resin composition for sealing arrange | positioned on the base material 2 according to the dimension of the semiconductor chip 3. FIG.

  Next, the substrate 2 is supported on the stage 52 and the semiconductor chip 3 is held on the bonding head 51. In this state, the bonding head 51 is moved toward the stage 52. Thereby, the semiconductor chip 3 is arrange | positioned in the position in which the thermosetting resin composition for sealing in the base material 2 is arrange | positioned. At this time, the semiconductor chip 3 is disposed in a state where the semiconductor chip 3 and the base material 2 are aligned so that the bump electrode 33 in the semiconductor chip 3 and the electrode pad 22 in the conductor wiring 21 of the base material 2 overlap.

  In this state, the semiconductor chip 3 and the substrate 2 are heated through the bonding head 51 and the stage 52, so that the sealing thermosetting resin composition and the bump electrode 33 are subjected to heat treatment. Then, the solder bump 32 is melted, so that the bump electrode 33 and the electrode pad 22 are electrically connected. Moreover, the sealing material 42 is formed by thermosetting the thermosetting resin composition for sealing, and thereby, the space between the semiconductor chip 3 and the substrate 2 is sealed with the sealing material 42. As described above, the semiconductor chip 3 is mounted on the base 2, the base 2, the semiconductor chip 3 mounted face-down on the base 2, and the gap between the base 2 and the semiconductor chip 3 is sealed. The semiconductor device 1 including the sealing material 42 to be obtained is obtained. The semiconductor chip 3 includes a plurality of bump electrodes 33, and the plurality of bump electrodes 33 are embedded in the sealing material 42.

  The heating temperature of the bump electrode 33 and the sealing thermosetting resin composition in the heat treatment exceeds the melting point of the solder bump 32 depending on the composition of the solder bump 32 and the sealing thermosetting resin composition. Is set as appropriate. For example, the maximum heating temperature in the heat treatment is in the range of 230 to 280 ° C. The heating time in the heat treatment is appropriately set in consideration of the melting point of the solder bumps 32, conditions of various facilities of the heating device, and the like. In particular, the heating time in the heat treatment is preferably in the range of 2 to 10 seconds. In this case, the productivity of the semiconductor device 1 is particularly high. In this embodiment, since the curing rate of the thermosetting resin composition for sealing is high, the thermosetting resin composition for sealing can be sufficiently cured even if the heating time is short as described above.

  In addition, the thermosetting resin composition for sealing according to the present embodiment can be applied to uses other than underfill. For example, a sealing thermosetting resin composition may be applied as an adhesive for bonding the semiconductor chip 3 and the heat dissipation component.

  In the present embodiment, for example, even when the gap between the substrate 2 and the semiconductor chip 3 is in the range of 5 to 150 μm and the interval between the adjacent bump electrodes 33 is 5 to 150 μm, excellent connection stability and connection Reliability and high heat dissipation are obtained. In particular, when the average particle size of the inorganic filler is in the range of 0.5 to 4.0 μm, high connection stability can be obtained even if the distance between the bump electrodes 33 is less than 60 μm or less than 50 μm.

[Preparation of composition]
About each Example and the comparative example, among the components shown to Tables 1-3, components other than an inorganic filler were mix | blended, and the mixture was prepared by stirring and mixing. After adding an inorganic filler to this mixture, it stirred further and mixed. This obtained the liquid thermosetting resin composition for sealing.

In addition, the detail of the component in a table | surface is as follows.
Acrylic resin 1: tricyclodecane dimethanol diacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., product number A-DCP.
Acrylic resin 2: bisphenol A type epoxy acrylate, manufactured by Showa Polymer Co., Ltd., product number VR-77.
-Acrylic resin 3: polyethylene glycol # 200 diacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., product number A-200.
Acrylic resin 4: 1,6-hexanediol diacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., product number A-HD-N.
Organic peroxide 1: Dicumyl peroxide (1 minute half-life temperature 175.2 ° C.).
Organic peroxide 2: manufactured by NOF Corporation, Perbutyl Z (1 minute half-life temperature 166.8 ° C.)
Organic peroxide 3: manufactured by NOF Corporation, perhexine 25B (1 minute half-life temperature 179.8 ° C.)
Organic peroxide 4: manufactured by NOF Corporation, perhexine 25B-40 (1 minute half-life temperature 194.3 ° C.).
Epoxy resin: Nippon Steel & Sumikin Chemicals, product number YDF8170.
Acid anhydride: manufactured by Mitsubishi Chemical, product number YH307.
-Imidazole: 2-phenyl-4-methylimidazole.
Inorganic filler 1: Aluminum nitride powder coupled with phosphate ester.
Inorganic filler 2: Aluminum nitride powder not subjected to coupling treatment.
・ Flux: Sebacic acid.

[Evaluation test]
The following evaluation test was done with respect to the thermosetting resin composition for sealing obtained in each Example and Comparative Example. The results are shown in Tables 1 to 3 below.

  In addition, Comparative Examples 1-3 is an example which used the epoxy resin instead of the acrylic resin in Examples 1-3, and was performed in order to confirm the reduction | decrease in the void by using an acrylic resin especially. In Examples 1-3, the influence was confirmed by changing the quantity of an initiator. In Examples 4 to 5 and Comparative Example 6, the effect was confirmed by changing the amount of flux. In Example 6 and Comparative Example 7, the influence was confirmed by changing the average particle diameter of the inorganic filler. In Example 7 and Comparative Example 4, the influence was confirmed by changing the content of the inorganic filler. In Comparative Example 5 and Examples 8 to 9, the effect was confirmed by changing the type of the initiator. In the comparative example 6, the influence was confirmed by using the acrylic resin which does not have a 5-membered ring and a 6-membered ring. In Comparative Example 7, the influence was confirmed by using an inorganic filler having a maximum particle size larger than 10 μm.

  Evaluation contents shown in Tables 1 to 3 will be described.

(1) Viscosity evaluation Viscosity evaluation was performed about the thermosetting resin composition for sealing shown in Examples 1-12 shown in Tables 1-3, and Comparative Examples 1-7. In the viscosity evaluation, using a B-type viscosity measuring device (trade name DV-II) manufactured by Brookfield, the rotor diameter used is 8.74 mm, and the setting temperature is 25 ° C., the rotation speed of the thermosetting resin composition for sealing is 50 rpm. The viscosity at was determined.

(2) Coating property evaluation Coating property evaluation was performed about the thermosetting resin composition for sealing shown in Examples 1-12 shown in Tables 1-3, and Comparative Examples 1-7. In the applicability evaluation, the sealing thermosetting resin composition was applied so as to draw a double cloth pattern using an air dispensing apparatus (manufactured by Musashi Engineering Co., Ltd.). In this case, “C” indicates a case where a coating film shape failure or stringing failure occurs, “B” indicates a case where the failure occurs but the degree thereof is slight, and a case where such a failure does not occur. Rated “A”. When the evaluation is “B”, it is considered that the evaluation “A” can be achieved by optimizing the coating method and the like.

(3) Thermal conductivity evaluation of hardened | cured material The thermal conductivity evaluation of hardened | cured material is the hardened | cured material of the thermosetting resin composition for sealing shown in Examples 1-12 shown in Tables 1-3 and Comparative Examples 1-7. Went about. In evaluating the thermal conductivity of the cured product, the sealing thermosetting resin composition is first heated from room temperature to 150 ° C. over 60 minutes, and then heated at 150 ° C. for 2 hours to obtain a diameter of 2 cm and a thickness. A 1 mm disc-shaped test piece was prepared. The thermal diffusion coefficient (α) of this test piece was measured by the laser flash method (t1 / 2 method), the specific heat (Cp) was measured by the DSC method, and the density (ρ) was measured according to JIS K6911. Thermal conductivity (= α × Cp × ρ) was calculated from these values. As a result, when the thermal conductivity is 2 W / m · K or more, “A”, when 1 W / m · K or more and less than 2 W / m · K, “B”, when less than 1 W / m · K, “C” ". In addition, when heat conductivity is 1 W / m * K or more, it can be evaluated that it has the outstanding heat conductivity.

(4) Semiconductor device evaluation A semiconductor chip having a size of 7.3 mm × 7.3 mm, a bump pitch of 50 μm, a bump number of 544, and a thickness of 0.15 mm was prepared. A bump electrode in a semiconductor chip includes a copper pillar having a height of 30 μm and a plan view size of 30 μm × 30 μm and a solder bump having a height of 15 μm. The solder bump is made of lead-free solder (Sn-3.5Ag: melting point 221 ° C.). Met. As a base material, the glass epoxy board | substrate provided with the copper conductor wiring in which the antirust film by the preflux process was provided was prepared. In the state which heated the stage of the flip chip bonder to the range of 60-100 degreeC, the base material was fixed on this stage. On this base material, 3.0-4.0 mg of the thermosetting resin composition for sealing was applied with a dispenser. The semiconductor chip is held by the bonding head of the flip chip bonder, the bonding head is heated to 130 ° C., the bonding head is brought close to the stage, and the semiconductor chip is applied with the sealing thermosetting resin composition on the base material. The bump electrode of the semiconductor chip and the electrode pad of the base material were placed in alignment with each other, and the semiconductor chip was pressed against the base material for 0.5 seconds. Subsequently, while applying a load of 30 N from the bonding head to the semiconductor chip, the temperature of the bonding head was raised to a maximum temperature of 260 ° C. over 1.5 seconds. Subsequently, after holding the temperature of the bonding head at the maximum temperature for 2 seconds, the holding of the semiconductor chip by the bonding head was released, and the bonding head was separated from the stage. The time from the placement of the semiconductor chip on the substrate to the separation of the bonding head from the stage was about 4 seconds. Thereby, a semiconductor device was obtained.

(4-1) Void Evaluation Voids in the sealing material in the semiconductor device were investigated using an ultrasonic flaw detector (SAT). As a result, “A” indicates that no voids having a diameter of 50 μm or more are observed, “B” indicates that 1 to 30 voids having a diameter of 50 μm or more are recognized, and 31 or more voids having a diameter of 50 μm or more. Was evaluated as “C”.

(4-2) Conductivity evaluation The electrical resistance between the bump electrode and the electrode pad in the semiconductor device was measured. As a result, “A” indicates that the measured value of electrical resistance is 30Ω or less, “B” indicates that the measured value of electrical resistance is 30Ω or more, and “C” indicates that the measured value of electrical resistance is infinite. And evaluated.

(4-3) Solder wettability (solder wettability to electrode pads)
The semiconductor device was cut at a surface including a connection portion between the bump electrode of the semiconductor chip and the electrode pad of the base material, and then the cross section was polished. This cross section was observed by SEM, and the wettability of the solder bump to the electrode pad was evaluated as follows.
A: The solder bumps are in contact with not only the upper surface but also the side surface of the electrode pad, and an alloy layer is formed between the electrode pad and the solder bump.
B: Only the upper surface of the electrode pad is in contact with the solder bump, but an alloy layer is formed between the electrode pad and the solder bump.
C: No alloy layer is observed between the electrode pad and the solder bump.

  If the evaluation is “A” or “B”, the semiconductor device can be regarded as a non-defective product, and if the evaluation is “C”, the semiconductor device is regarded as having a problem.

  FIG. 2A shows an SEM photograph of a cross section in the case of Example 6 having an evaluation “A”. FIG. 2B shows a SEM photograph of a cross section in the case of Example 3 having an evaluation “B”. FIG. 2C shows an SEM photograph in the case of Comparative Example 6 having an evaluation “C”.

(4-4) Moisture absorption reflow test The semiconductor device was exposed to conditions of 60 ° C. and 60% RH for 192 hours. Subsequently, the semiconductor device was passed through a reflow furnace three times with a temperature profile of a maximum temperature of 260 ° C. Subsequently, the presence or absence of cracks in the sealing material and the presence or absence of peeling at the interface between the sealing material and the semiconductor chip and the base material were investigated using an ultrasonic flaw detector (SAT).

  For each of the examples and comparative examples, this test was performed on five samples, and as a result, no crack or interface peeling was observed in any of the samples. The case where cracks or peeling was observed even at one location was evaluated as “B”.

(4-5) Evaluation of Filler Filling The semiconductor device was cut at the surface including the connection portion between the bump electrode of the semiconductor chip and the electrode pad of the base material, and then the cross section was polished. This cross section was observed by SEM, and the result was evaluated as follows.
A: The inorganic filler particles do not intervene between the solder bumps and the electrode pads, or the particle size of the inorganic filler intervenes between the solder bumps and the electrode pads is less than 3 μm.
B: Although the particle size of the inorganic filler is interposed between the solder bump and the electrode pad, the maximum particle size of the particle is 3 μm or more and less than 5 μm.
C: The particle size of the inorganic filler is interposed between the solder bump and the electrode pad, and the maximum particle size of this particle is 5 μm or more.

  3A shows an SEM photograph of a cross section in the case of Example 5 where the evaluation is “A”. FIG. 3B shows an SEM photograph of a cross-section of a portion where filler entrapment was observed in Comparative Example 6 with an evaluation “B”. FIG. 3C shows an SEM photograph of a cross section of a portion where filler entrapment was observed in Comparative Example 7 having an evaluation “C”.

(5) Evaluation of Semiconductor Device (Narrow Pitch) A semiconductor chip having a size of 7.3 mm × 7.3 mm, a bump pitch of 40 μm, a bump diameter of 26 μm, and a number of bumps of 1352 was prepared. The bump electrode in the semiconductor chip was provided with a copper pillar having a height of 15 μm and a solder bump having a height of 10 μm, and the solder bump was made of lead-free solder (Sn-3.5Ag: melting point 221 ° C.). As the substrate, a silicon interposer provided with a Ni / Au electrode was prepared. In the state which heated the stage of the flip chip bonder to the range of 60-100 degreeC, the base material was fixed on this stage. On this base material, 3.0-4.0 mg of the thermosetting resin composition for sealing was applied with a dispenser. The semiconductor chip is held by the bonding head of the flip chip bonder, the bonding head is heated to 130 ° C., the bonding head is brought close to the stage, and the semiconductor chip is applied with the sealing thermosetting resin composition on the base material. The bump electrode of the semiconductor chip and the electrode pad of the base material were placed in alignment with each other, and the semiconductor chip was pressed against the base material for 0.5 seconds. Subsequently, while applying a load of 30 N from the bonding head to the semiconductor chip, the temperature of the bonding head was raised to a maximum temperature of 260 ° C. over 1.5 seconds. Subsequently, after holding the temperature of the bonding head at the maximum temperature for 2 seconds, the holding of the semiconductor chip by the bonding head was released, and the bonding head was separated from the stage. The time from the placement of the semiconductor chip on the substrate to the separation of the bonding head from the stage was about 4 seconds. Thereby, a semiconductor device was obtained.

  About this semiconductor device, said void evaluation, conduction | electrical_connection evaluation, the wettability evaluation of a solder, a moisture absorption reflow test, and the inclusion evaluation of the filler were performed.

DESCRIPTION OF SYMBOLS 1 Semiconductor device 2 Base material 21 Conductor wiring 3 Semiconductor chip 33 Bump electrode 42 Sealing material

Claims (14)

A sealing thermosetting resin composition for sealing a gap between a substrate and a semiconductor chip mounted face down on the substrate,
An acrylic resin having at least one of a five-membered ring and a six-membered ring and being liquid at 25 ° C .;
An inorganic filler having a maximum particle size of 10.0 μm or less,
The acrylic resin is in the range of 10 to 40% by mass, the inorganic filler is in the range of 60 to 90% by mass with respect to the total amount of the acrylic resin and the inorganic filler,
A thermosetting resin composition for sealing further containing an organic peroxide having a one-minute half-life temperature of 120 to 190 ° C. The thermosetting resin composition for sealing according to claim 1, wherein the thermosetting resin composition for sealing further contains a flux. The thermosetting resin composition for sealing according to claim 1 or 2, wherein the organic peroxide is in a range of 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the acrylic resin. The thermosetting resin composition for sealing according to any one of claims 1 to 3, which is cured within 10 seconds from the start of heating by being heated at any temperature within a range of 220 to 280 ° C. object. The thermosetting resin composition for sealing according to any one of claims 1 to 4, wherein an average particle size of the inorganic filler is in a range of 0.1 to 10.0 µm. The sealing thermosetting resin composition according to any one of claims 1 to 4, wherein an average particle size of the inorganic filler is in a range of 0.5 to 4.0 µm. The seal according to any one of claims 1 to 6, wherein a viscosity measured using a B-type rotational viscometer under conditions of 25 ° C and a rotational speed of 0.5 rpm is within a range of 20 to 100 Pa · s. A thermosetting resin composition for stopping. The thermosetting resin composition for sealing according to any one of claims 1 to 7, wherein the inorganic filler has a thermal conductivity of 20 W / m · K or more. The thermosetting resin composition for sealing according to any one of claims 1 to 8, wherein the inorganic filler is made of at least one material selected from the group consisting of aluminum nitride, alumina, boron nitride, and silicon carbide. . The thermosetting resin composition for sealing according to any one of claims 1 to 9, wherein the inorganic filler is subjected to a coupling treatment. The thermosetting resin composition for sealing according to any one of claims 1 to 10 is disposed on a base material provided with conductor wiring,
In a position where the sealing thermosetting resin composition on the substrate is disposed, a semiconductor chip including a bump electrode is disposed face down, and the bump electrode is disposed on the conductor wiring,
By heat-treating the thermosetting resin composition for sealing and the bump electrode, the thermosetting resin composition for sealing is cured to form a sealing material and the bump electrode is melted. A method of manufacturing a semiconductor device, comprising electrically connecting the bump electrode and the conductor wiring. A base material, a semiconductor chip mounted face-down on the base material, and a sealing material that seals between the base material and the semiconductor chip, wherein the sealing material comprises: A semiconductor device comprising a cured product of the sealing thermosetting resin composition according to any one of 10. The semiconductor chip includes a plurality of bump electrodes,
The plurality of bump electrodes are embedded in the sealing material,
The shortest pitch between the plurality of bump electrodes is in the range of 5.0 to 150 μm.
The semiconductor device according to claim 12. The semiconductor chip includes a plurality of bump electrodes,
The plurality of bump electrodes are embedded in the sealing material,
The diameter of the plurality of bump electrodes is in the range of 3 to 90 μm.
The semiconductor device according to claim 12 or 13.