Method for manufacturing semiconductor adhesive films, dicing die bonding films, and semiconductor devices.

Abstract

To suppress local deformation in the thickness direction of an adhesive film following thermal hardening in an adhesive film for semiconductor with the thermosetting property used for bonding a semiconductor chip to an adherend.SOLUTION: There is provided an adhesive film for semiconductor with the thermosetting property used for manufacturing a semiconductor device by a method comprising the steps of: arranging a second semiconductor chip and an adhesive film on a structure having a substrate, a first semiconductor chip mounted on the substrate and a plurality of spacers arranged around the first semiconductor chip on the substrate; and bonding the second semiconductor chip to the structure by thermally hardening the adhesive film. The adhesive film shows the minimum melt viscosity equal to or greater than 2500 Pa s and equal to or less than 10000 Pa s within a range between 90 and 180°C. The minimum melt viscosity is the value obtained by measuring the dynamic viscoelasticity of the adhesive film within the temperature range including the range between 90 and 180°C under a condition of the temperature rising speed 5°C / min and the frequency 1 Hz.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an adhesive film for semiconductors, a dicing die bonding film, and a method for manufacturing a semiconductor device.

Background Art

[0002] There may be a need to embed a wire connected to another semiconductor chip by an adhesive film for semiconductors for adhering a semiconductor chip to an adherent (for example, Patent Document 1). Such a wire-embedded adhesive film is required to have a certain degree of high fluidity in the process of its thermosetting in order to appropriately embed the wire.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, a conventional adhesive film having a certain degree of high fluidity causes deformation in the thickness direction during thermosetting, and as a result, a portion where the adhesive film becomes locally thin may occur. A portion where the adhesive film becomes locally thin can cause cracks in, for example, a semiconductor chip.

[0005] One aspect of the present disclosure relates to a thermosetting adhesive film for semiconductors used for adhering a semiconductor chip to an adherent while embedding a wire connected to another semiconductor chip, and relates to suppressing local deformation in the thickness direction of the adhesive film accompanying thermosetting.

Means for Solving the Problems

[0006] One aspect of this disclosure relates to a thermosetting semiconductor adhesive film used to bond a semiconductor chip to a substrate while embedding wires connected to other semiconductor chips. The adhesive film exhibits a minimum melt viscosity of 2500 Pa·s to 10000 Pa·s in the range of 90 to 180°C. The maximum value of tanδ and the minimum melt viscosity are determined by measuring the dynamic viscoelasticity of the adhesive film in a temperature range including 90 to 180°C under the conditions of a heating rate of 5°C / min and a frequency of 1 Hz.

[0007] Another aspect of this disclosure relates to a dicing die bonding film comprising a dicing film and a semiconductor adhesive film provided on the dicing film.

[0008] Another aspect of the present disclosure relates to a method for manufacturing a semiconductor device, comprising: arranging a second semiconductor chip and an adhesive film on a structure having a substrate and a first semiconductor chip mounted on the substrate, such that the adhesive film is interposed between the structure and the second semiconductor chip; and thermally curing the adhesive film to bond the second semiconductor chip to the structure. The adhesive film may be the semiconductor adhesive film described above. Wires are connected to the first semiconductor chip, and part or all of the wires are embedded by the adhesive film. [Effects of the Invention]

[0009] Regarding thermosetting semiconductor adhesive films used to bond semiconductor chips to a substrate while embedding wires connected to other semiconductor chips, it is possible to suppress local deformation of the adhesive film in the thickness direction due to thermal curing. [Brief explanation of the drawing]

[0010] [Figure 1] This is a cross-sectional view showing an example of a laminated film having an adhesive film. [Figure 2]This is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. [Figure 3] This is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. [Figure 4] This is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. [Figure 5] This is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. [Figure 6] This is a cross-sectional view showing an example of a method for manufacturing a semiconductor device. [Figure 7] This graph shows the relationship between the shear viscosity of an adhesive film and temperature. [Figure 8] This graph shows the relationship between the tanδ of the adhesive film and temperature. [Figure 9] This is a schematic cross-sectional view showing an evaluation adhesive for evaluating the deformation of the adhesive film during curing. [Modes for carrying out the invention]

[0011] The present invention is not limited to the following examples. In the following examples, the components (including steps, etc.) are not essential unless otherwise specified. The sizes of the components in each figure are conceptual, and the relative relationships between the components are not limited to those shown in each figure. The numerical values ​​and their ranges exemplified below are not limiting to this disclosure.

[0012] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described in stages in this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. In numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples.

[0013] In this specification, "(meth)acrylate" means acrylate or its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl group" and "(meth)acrylic copolymer".

[0014] FIG. 1 is a cross-sectional view showing an example of a laminated film having an adhesive film. The laminated film 50 shown in FIG. 1 includes a base material 20, an adhesive film 12, and a protective film 30 in this order. The adhesive film, the adhesive film 12, can be a thermosetting adhesive film for semiconductors used to adhere a semiconductor chip to an adherend while embedding a wire connected to another semiconductor chip. The base material 20 may be a dicing film, and in that case, the laminated film 50 can be used as a dicing die bonding film.

[0015] The adhesive film 12 may exhibit a minimum melt viscosity of 2500 Pa·s or more and 10000 Pa·s or less in the range of 90 to 180°C. The adhesive film 12 may exhibit a maximum value of tanδ of 1.0 or less in the range of 90 to 180°C. The minimum melt viscosity and the maximum value of tanδ are values obtained by measuring the dynamic viscoelasticity of the adhesive film 12 in a temperature range including the range of 90 to 180°C under the conditions of a temperature increase rate of 5°C / min and a frequency of 1 Hz.

[0016] The minimum melt viscosity of the adhesive film means the minimum value of the shear viscosity (or complex viscosity η * ) measured by measuring the dynamic viscoelasticity of the adhesive film 12. The shear viscosity of the adhesive film 12 usually decreases with the increase in temperature and then increases with the progress of the curing reaction. When the minimum melt viscosity of the adhesive film 12 is 10000 Pa·s or less, the adhesive film 12 can appropriately embed wires and the like. From the same perspective, the minimum melt viscosity of the adhesive film 12 may be 9000 Pa·s or less, 8500 Pa·s or less, 8000 Pa·s or less, 7500 Pa·s or less, 7000 Pa·s or less, 6500 Pa·s or less, 6000 Pa·s or less, or 5500 Pa·s or less.

[0017] Maintaining the shear viscosity of the adhesive film 12 at a certain level within the range of 90 to 180°C can also contribute to suppressing the deformation of the adhesive film 12 during the curing process. From this perspective, the minimum melt viscosity of the adhesive film 12 within the range of 90 to 180°C may be 2500 Pa·s or more, 3000 Pa·s or more, or 3500 Pa·s or more.

[0018] When the tanδ of the adhesive film 12 is 1.0 or less within the range of 90 to 180°C, the deformation of the adhesive film 12 during the thermosetting process tends to be further suppressed. From a similar perspective, the maximum value of tanδ of the adhesive film 12 within the range of 90 to 180°C may be 0.95 or less, 0.90 or less, 0.85 or less, 0.80 or less, 0.75 or less, or 0.70 or less, and may also be 0.50 or more.

[0019] The thickness of the adhesive film 12 may be, for example, 1 μm or more, 3 μm or more, 20 μm or more, 25 μm or more, 30 μm or more, 35 μm or more, 40 μm or more, or 50 μm or more, and may also be 200 μm or less, 150 μm or less, 120 μm or less, 80 μm or less, or 60 μm or less. From the perspective of using it to adhere a semiconductor chip to an adherend while embedding a wire connected to another semiconductor chip, the thickness of the adhesive film 12 may be 25 to 80 μm.

[0020] The adhesive film 12 includes, for example, a thermosetting resin and a curing agent that reacts with the thermosetting resin. The thermosetting resin is a compound that forms a crosslinked structure by a curing reaction including reaction with the curing agent and / or self-polymerization, and examples include epoxy resins which are compounds having epoxy groups. Examples of epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin, stilbene type epoxy resin, triazine skeleton-containing epoxy resin, fluorene skeleton-containing epoxy resin, triphenolphenolmethane type epoxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, and diglycidyl ether compounds derived from polyfunctional phenol compounds or polycyclic aromatic compounds (such as anthracene). These may be used individually or in combination of two or more. The epoxy resin may be a combination of o-cresol novolac type epoxy resin and bisphenol F type epoxy resin and / or bisphenol A type epoxy resin.

[0021] The curing agent that can be combined with the epoxy resin as a thermosetting resin may include, for example, a phenolic resin. Examples of phenolic resins used as curing agents include novolac-type phenolic resins obtained by condensing or co-condensing phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and / or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene with compounds having an aldehyde group such as formaldehyde under an acidic catalyst; phenolic aralkyl resins and / or naphthols synthesized from phenols such as allylated bisphenol A, allylated bisphenol F, allylated naphthalenediol, phenol novolac, and / or naphthols with dimethoxyp-xylene or bis(methoxymethyl)biphenyl; and naphthol aralkyl resins. These may be used individually or in combination of two or more.

[0022] The total content of the thermosetting resin and curing agent may be, for example, 10% by mass or more or 15% by mass or more, and may be 80% by mass or less, 75% by mass or less, 70% by mass or less, 65% by mass or less, 60% by mass or less, 55% by mass or less, 50% by mass or less, 45% by mass or less, 35% by mass or less, or 30% by mass or less.

[0023] The adhesive film 12 may contain an imidazole compound. The imidazole compound is a compound having an imidazole ring and can function, for example, as a curing accelerator to promote the curing reaction between an epoxy resin and its curing agent (such as a phenolic resin). The type and content of the imidazole compound may be related to the maximum tanδ and minimum melt viscosity of the adhesive film 12. Imidazole compounds with a low softening point or melting point tend to increase the maximum tanδ and minimum melt viscosity. For example, at least one imidazole compound selected from the group consisting of 1-cyanoethyl-2-phenylimidazole, 2-phenylimidazole, and 1-benzyl-2-methylimidazole tends to yield an adhesive film with a maximum tanδ of 1.0 or less and / or a minimum melt viscosity of 2500 Pa·s or more.

[0024] A higher imidazole compound content tends to result in a higher maximum value of tanδ and a higher minimum melt viscosity. For example, the imidazole compound content may be 0.06% by mass or more, 0.07% by mass or more, 0.08% by mass or more, 0.09% by mass or more, 0.10% by mass or more, or 0.11% by mass or more, based on the mass of the adhesive film 12, and may also be 1.0% by mass or less, 0.90% by mass or less, 0.80% by mass or less, 0.70% by mass or less, 0.60% by mass or less, 0.5% by mass or less, 0.40% by mass or less, 0.30% by mass or less, or 0.20% by mass or less.

[0025] If the thermosetting resin contains epoxy resin, from the same viewpoint as above, the imidazole content may be 0.30 parts by mass or more, 0.35 parts by mass or more, 0.40 parts by mass or more, 0.45 parts by mass or more, or 0.50 parts by mass or more per 100 parts by mass of epoxy resin content, and may also be 5.0 parts by mass or less, 4.5 parts by mass or less, 4.0 parts by mass or less, 3.5 parts by mass or less, 3.0 parts by mass or less, 2.5 parts by mass or less, 2.0 parts by mass or less, 1.5 parts by mass or less, 1.0 part by mass or less, 0.95 parts by mass or less, 0.90 parts by mass or less, 0.85 parts by mass or less, 0.80 parts by mass or less, 0.75 parts by mass or less, 0.70 parts by mass or less, 0.65 parts by mass or less, or 0.60 parts by mass or less.

[0026] Even when using curing accelerators other than imidazole compounds, by appropriately adjusting their reactivity and content, it is possible to obtain adhesive films exhibiting a maximum tanδ of 1.0 or less and / or a minimum melt viscosity of 2500 Pa·s or more.

[0027] The adhesive film 12 may further contain an inorganic filler. When an inorganic filler is introduced, the maximum value of tanδ and the minimum melt viscosity of the adhesive film 12 tend to increase. The inorganic filler content may be 10% by mass or more, 15% by mass or more, 20% by mass or more, 25% by mass or more, 30% by mass or more, or 35% by mass or more, based on the mass of the adhesive film 12, and may also be 60% by mass or less, 55% by mass or less, 50% by mass or less, or 45% by mass or less.

[0028] The inorganic filler may be at least one selected from, for example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, and silica. From the viewpoint of adjusting the melt viscosity, the inorganic filler may also contain silica.

[0029] The average particle size of the inorganic filler may be 0.01 μm or larger, or 0.03 μm or larger, and may also be 1.5 μm or smaller, 1.0 μm or smaller, 0.8 μm or smaller, 0.08 μm or smaller, or 0.06 μm or smaller, from the viewpoint of fluidity. Two or more inorganic fillers with different average particle sizes may be combined. The average particle size refers to the value obtained by converting from the BET specific surface area.

[0030] The adhesive film 12 may contain an elastomer. When an elastomer is introduced, the maximum value of tanδ and the minimum melt viscosity of the adhesive film 12 tend to increase. The elastomer content may be 5% by mass or more, 10% by mass or more, or 15% by mass or more, based on the mass of the adhesive film 12, and may also be 50% by mass or less, 45% by mass or less, 40% by mass or less, 35% by mass or less, or 30% by mass or less.

[0031] The elastomer may contain an acrylic resin. Here, acrylic resin means a polymer containing monomer units derived from (meth)acrylic acid ester. The content of constituent units derived from (meth)acrylic acid ester in the acrylic resin may be, for example, 70% or more by mass, 80% or more by mass, or 90% or more by mass, based on the total amount of acrylic resin. The acrylic resin may contain monomer units derived from (meth)acrylic acid ester having crosslinkable functional groups such as epoxy groups, alcoholic or phenolic hydroxyl groups, and carboxyl groups. The acrylic resin may also be acrylic rubber, which is a copolymer containing (meth)acrylic acid ester and acrylonitrile as monomer units.

[0032] The glass transition temperature (Tg) of an elastomer (e.g., acrylic resin) may be -50°C or higher, -30°C or higher, 0°C or higher, or 3°C or higher, and may be 50°C or lower, 45°C or lower, 40°C or lower, 35°C or lower, 30°C or lower, or 25°C or lower. The glass transition temperature (Tg) refers to the value measured using a DSC (Differential Scanning Calorimeter) (e.g., Rigaku Corporation's "Thermo Plus 2"). The Tg of an elastomer can be adjusted to a desired range by adjusting the type and content of the constituent units that make up the elastomer (in the case of acrylic resin, constituent units derived from (meth)acrylic acid ester).

[0033] The weight-average molecular weight (Mw) of the elastomer (e.g., acrylic resin) may be 100,000 or more, 200,000 or more, or 300,000 or more, and may be 3,000,000 or less, 2,000,000 or less, or 1,000,000 or less. When the Mw of the elastomer is within this range, the viscoelasticity of the adhesive film 12 tends to be easily controlled appropriately. Mw refers to a value calculated using a calibration curve with standard polystyrene, measured by gel permeation chromatography (GPC).

[0034] Examples of commercially available acrylic resins include SG-70L, SG-708-6, WS-023 EK30, SG-280 EK23, SG-P3 (all manufactured by Nagase ChemteX Corporation), and H-CT-865 (manufactured by Showa Denko Materials Corporation).

[0035] The adhesive film 12 may further contain a coupling agent. The coupling agent may be a silane coupling agent. Examples of silane coupling agents include γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, and 3-(2-aminoethyl)aminopropyltrimethoxysilane. These may be used individually or in combination of two or more.

[0036] The adhesive film 12 may further contain other components such as pigments, ion capture agents, and antioxidants.

[0037] The substrate 20 constituting the laminated film 50 may be a resin film, and examples include films of polytetrafluoroethylene, polyethylene, polypropylene, polymethylpentene, polyethylene terephthalate, or polyimide. The thickness of the resin film as the substrate 20 may be, for example, 60 to 200 μm or 70 to 170 μm.

[0038] The base material 20 may be a dicing film, and the laminated film 50 may be a dicing die bonding film. The dicing die bonding film may be in tape form.

[0039] Examples of dicing films include resin films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. The dicing film may be a resin film whose surface has been treated by primer application, UV treatment, corona discharge treatment, polishing treatment, or etching treatment as needed. The dicing film may be adhesive. An adhesive dicing film may be, for example, a resin film to which adhesiveness has been imparted, or a laminate having a resin film and an adhesive layer provided on one side thereof. The adhesive layer can be formed from a pressure-sensitive or UV-curable adhesive. A pressure-sensitive adhesive is an adhesive that exhibits a certain level of adhesiveness with short-term pressure. A radiation-curable adhesive is an adhesive that has the property of decreasing adhesiveness upon irradiation with radiation (e.g., ultraviolet light). The thickness of the adhesive layer can be appropriately set according to the shape and dimensions of the semiconductor device, but may be, for example, 1 to 100 μm, 5 to 70 μm, or 10 to 40 μm. The thickness of the substrate 20, which is the dicing film, may be 60-150 μm or 70-130 μm from the viewpoint of economy and ease of handling of the film.

[0040] The protective film 30 may be a resin film similar to the base material 20. The thickness of the protective film 30 may be, for example, 15 to 200 μm or 70 to 170 μm.

[0041] Figures 2, 3, 4, 5, and 6 are cross-sectional views showing an example of a method for manufacturing a semiconductor device using the adhesive film 12 described above.

[0042] An example of a method for manufacturing a semiconductor device, as shown in Figure 2, includes preparing a structure 15 having a substrate 1 and a first semiconductor chip T1 mounted on the substrate 1, and preparing an adhesive chip TA having a second semiconductor chip T2 and an adhesive film 12 attached thereto. The structure 15 further includes a plurality of spacers 3 arranged around the first semiconductor chip on the substrate 1.

[0043] The first semiconductor chip T1 is bonded to the substrate 1 by a first adhesive film 11. The first semiconductor chip T1 is connected to a wire w on the side opposite to the substrate 1. The first semiconductor chip T1 may be a controller chip. The substrate 1 may be an organic substrate or a metal substrate such as a lead frame. The thickness of the substrate 1 may be, for example, 90 to 300 μm. The spacer 3 may be one that is commonly used in semiconductor devices having a dolmen structure. The height of the spacer 3 from the substrate 1 may be greater than the height of the first semiconductor chip T1 from the substrate 1.

[0044] The adhesive-bonded chip TA, consisting of a second semiconductor chip T2 and an adhesive film 12, can be prepared, for example, using a dicing die bonding film having a similar configuration to the laminated film 50 illustrated in Figure 1. In this case, for example, the laminated film 50 (dicing die bonding film) is attached to one side of a semiconductor wafer with the adhesive film 12 facing the semiconductor wafer. The side to which the adhesive film 12 is attached may be the circuit side of the semiconductor wafer or the opposite back side. The second semiconductor chip T2 is formed by dividing the semiconductor wafer to which the laminated film 50 (dicing die bonding film) is attached by dicing. Examples of dicing include blade dicing using a rotary blade and a method of cutting the adhesive film 12 together with the semiconductor wafer using a laser. After dicing, the adhesive strength of the dicing film may be reduced by ultraviolet irradiation. The second semiconductor chip T2 is picked up together with the divided adhesive film 12.

[0045] The thickness of the second semiconductor chip may be, for example, 1 to 100 μm. The width of the second semiconductor chip T2 may be, for example, 20 mm or less. The width (or length of one side) of the second semiconductor chip T2 may be 3 to 15 mm, or 5 to 10 mm.

[0046] As shown in Figure 3, the second semiconductor chip T2 and the adhesive film 12 are placed on the structure 15, with the adhesive film 12 interposed between the structure 15 and the second semiconductor chip T2. In the example in Figure 3, the adhesive film 12 is placed on the spacer 3 of the structure 15, and the adhesive film 12 and the first semiconductor chip T1 are separated. By thermally curing the adhesive film 12 in this state, the second semiconductor chip T2 is bonded to the structure 15 (adhesion body), as shown in Figure 4. After thermal curing, the adhesive film 12 is in contact with the first semiconductor chip T1 and embeds a portion of the wire w connected to the first semiconductor chip T1. The heating temperature for thermal curing of the adhesive film 12 may be constant or vary in stages. The heating temperature may be a maximum of 90 to 180°C. The adhesive film 12 is thermally cured under pressure, atmospheric pressure, or reduced pressure. The adhesive film 12, designed based on the maximum value of tanδ and / or minimum melt viscosity, can properly embed the wire w through moderate flow during the thermosetting process and form a cured product in which local deformation in the thickness direction is suppressed.

[0047] Next, as shown in Figure 5, a wire w is provided to connect the second semiconductor chip T2 and the substrate 1. Furthermore, a third semiconductor chip T3 and a fourth semiconductor chip T4 may be sequentially laminated on the side of the second semiconductor chip T2 opposite to the substrate 1, with an adhesive film 13 in between. A wire w is provided to connect the third semiconductor chip T3 or the fourth semiconductor chip T4 to the substrate 1. In the example of Figure 5, the number of semiconductor chips laminated on the spacer 3 is 3, but this number may be 4 or more.

[0048] As shown in Figure 6, a semiconductor device 100 having a dolmen structure is obtained by forming a sealing layer 60 that seals a structure having multiple semiconductor chips, including a first semiconductor chip T1 and a second semiconductor chip T2. The sealing layer 60 also fills the vicinity of the edges of the first semiconductor chip. If there is local deformation in the thickness direction of the adhesive film 12, the sealing layer 60 may seep into that area, which could cause defects such as cracks in the second semiconductor chip T2. Such defects can be avoided by suppressing the deformation of the adhesive film 12. [Examples]

[0049] The present invention is not limited to the following embodiments.

[0050] 1. Preparation of adhesive film Adhesive varnishes containing the following materials in the amounts shown in Table 1 (unit: parts by mass) were prepared. The amounts of SG-P3 (elastomer) and SC2050-HLG shown in Table 1 represent the amount of solids (acrylic rubber or silica filler) excluding the solvent. (A) Epoxy resin • N-500P-10 (product name, manufactured by DIC Corporation, o-cresol novolac) (Epoxy resin, epoxy equivalent: 203 g / eq) EXA-830CRP (product name, manufactured by DIC Corporation, bisphenol F type epoxy resin, epoxy equivalent: 158-168 g / eq) (B) Hardener (phenol resin) • MEH-7800M (product name, manufactured by Meiwa Chemical Co., Ltd., phenol novolac type phenolic resin, hydroxyl group equivalent: 175 g / eq, softening point: 61~90°C) (C) Inorganic filler • SC2050-HLG (product name, manufactured by Admatex Co., Ltd., silica filler dispersion, average particle size: 0.50 μm) (D) Elastomer • SG-P3 (product name, acrylic rubber, weight-average molecular weight: 800,000, Tg: 12℃, cyclohexanone solution) (E) Coupling agent • Z-6119 (product name, manufactured by Dow Toray Industries, Inc., 3-ureidopropyltriethoxysilane) • A-189 (Product name, manufactured by Nippon Unicar Co., Ltd., γ-mercaptopropyltrimethoxysilane) (F) Curing accelerator • 2PZ-CN (product name, manufactured by Shikoku Chemicals Co., Ltd., 1-cyanoethyl-2-phenylimidazole)

[0051] Each prepared adhesive varnish was filtered through a 500-mesh filter and degassed under vacuum. The degassed adhesive varnish was applied to a release-treated polyethylene terephthalate (PET) film (support film). The coating was dried in two stages: 90°C for 5 minutes, followed by 130°C for 5 minutes, to form a B-stage adhesive film (thickness: 50 μm) on the support film.

[0052] 2. Evaluation (1) Viscoelasticity of adhesive film Eight adhesive films of predetermined sizes were prepared by cutting them from an adhesive film. These were laminated on a 70°C hot plate using a rubber roll to prepare a laminate with a thickness of 400 μm. This laminate was punched out with a φ9 mm punch to prepare a sample. The sample was mounted on the measuring jig of a rotary viscoelasticity measuring device (manufactured by T.A. Instrument Japan Co., Ltd., product name: ARES-RDA). At this point, the gap of the measuring jig was adjusted so that the load on the sample was 10 to 15 g. Subsequently, the viscoelasticity of the sample was measured under the following conditions. Figure 7 is a graph showing the relationship between shear viscosity (complex viscosity) and temperature for the adhesive films of Examples 1 to 3 and the comparative example. Figure 8 is a graph showing the relationship between tanδ and temperature for the adhesive films of Examples 1 to 3 and the comparative example. From the measurement results, the minimum melt viscosity and the maximum value of tanδ in the range of 90 to 180°C were read. The minimum melt viscosity is the minimum value of the shear viscosity (complex viscosity) in the range of 90 to 180°C. Measurement conditions: Disc plate: Aluminum, circular (8mm diameter) Measurement frequency: 1Hz Heating rate: 5°C / min Strain: 5% Measurement temperature: 35~180℃ Initial load: 100g

[0053] (2) Deformation of the adhesive film Figure 9 is a schematic cross-sectional view showing an evaluation adhesive for evaluating the deformation of the adhesive film during curing. A first semiconductor chip T1 (thickness: 60 μm) with dimensions of 3 mm × 2 mm and four spacers 3 (thickness: 100 μm) surrounding the first semiconductor chip T1 were placed on a substrate 1. The first semiconductor chip T1 and the spacers 3 were bonded to the substrate 1 via a first adhesive film 11 (thickness: 20 μm). The height difference between the spacers 3 and the first semiconductor chip T1 on the substrate 1 was 40 μm. The distance between the first semiconductor chip T1 and each spacer 3 was 1.5 mm on the short side of the first semiconductor chip T1 and 1.0 mm on the long side of the first semiconductor chip T1.

[0054] An adhesive-backed chip was prepared, comprising a second semiconductor chip T2 measuring 12 mm x 6 mm and a second adhesive film 12 attached to it. The adhesive films prepared in "1. Preparation of Adhesive Film" were used as the second adhesive film 12. The prepared adhesive-backed chip was pressed onto a spacer 3 so as to cover the first semiconductor chip T1. The formed structure was heated in an oven at a maximum temperature of 140°C to cure the second adhesive film 12. Subsequently, the space between the first semiconductor chip T1 and the cured adhesive film 12 of the structure was observed using an ultrasonic microscope (SAM) with an ultrasonic digital imaging system (Insight, IS-350 or IS-450). If no partial black shadows were observed, it was evaluated as "OK," and if partial black shadows were observed, it was evaluated as "NG." Partial black shadows are due to deformation of the adhesive film 12; if these are not observed, the adhesive film is considered to have good embedding properties. The conditions for the adhesive film SAM were as follows. ·Reflection method • Frequency: 75MHz ·Focal length: 9mm Furthermore, the structure was cut in half, and the adhesive film 12 within the cross-section was observed using an optical microscope to measure the minimum thickness t of the second adhesive film 12.

[0055] The evaluation results are shown in Table 1. It was confirmed that the adhesive films of Examples 1 to 5 could suppress localized shrinkage in the thickness direction due to curing. The adhesive film of the comparative example deformed significantly in the thickness direction near the edge of the first semiconductor chip T1 due to curing, and as a result, a portion with a thickness of 0 μm, i.e., a portion where the adhesive film 12 had substantially disappeared, was observed. The adhesive films of Examples 1 to 5 also showed excellent embeddability.

[0056] [Table 1] [Explanation of symbols]

[0057] 1...Substrate, 3...Spacer (thickness: 100 μm), 11, 12, 13...Adhesive film, 15...Structure, 20...Base material (dicing film), 30...Protective film, 50...Laminated film (dicing die bonding film), 60...Sealing layer, 100...Semiconductor device, T1...First semiconductor chip, T2...Second semiconductor chip, w...Wire.

Claims

1. The method involves preparing a structure having a substrate, a first semiconductor chip mounted on the substrate, and a plurality of spacers arranged around the first semiconductor chip on the substrate. The second semiconductor chip and adhesive film are arranged on the aforementioned structure such that the adhesive film is interposed between the structure and the second semiconductor chip. The adhesive film is heat-cured, thereby bonding the second semiconductor chip to the structure. A thermosetting semiconductor adhesive film used for manufacturing semiconductor devices by a method including, The adhesive film exhibits a minimum melt viscosity of 2500 Pa·s or more and 10000 Pa·s or less in the range of 90 to 180°C. A semiconductor adhesive film in which the minimum melt viscosity is a value determined by measuring the dynamic viscoelasticity of the adhesive film in a temperature range including 90 to 180°C under the conditions of a heating rate of 5°C / min and a frequency of 1 Hz.

2. The semiconductor adhesive film according to claim 1, wherein the adhesive film comprises a thermosetting resin containing an epoxy resin, a curing agent, and an imidazole compound.

3. The semiconductor adhesive film according to claim 2, wherein the content of the imidazole compound is 0.30 to 5.0 parts by mass per 100 parts by mass of the epoxy resin.

4. The semiconductor adhesive film according to any one of claims 1 to 3, wherein the adhesive film contains an inorganic filler, and the content of the inorganic filler is 35 to 50% by mass based on the mass of the adhesive film.

5. The semiconductor adhesive film according to any one of claims 1 to 4, wherein the adhesive film contains an elastomer, and the elastomer content is 15 to 30% by mass based on the mass of the adhesive film.

6. The semiconductor adhesive film according to any one of claims 1 to 5, wherein the adhesive film has a thickness of 25 to 80 μm.

7. The semiconductor adhesive film according to any one of claims 1 to 6, wherein, after the adhesive film is heat-cured, the height of the spacer from the substrate is greater than the height of the first semiconductor chip from the substrate.

8. The semiconductor adhesive film according to any one of claims 1 to 7, wherein the adhesive film is heat-cured so that it comes into contact with the first semiconductor chip.

9. Dicing film and A semiconductor adhesive film according to any one of claims 1 to 6 provided on the dicing film, A dicing die bonding film equipped with [a specific feature].

10. A structure having a substrate, a first semiconductor chip mounted on the substrate, and a plurality of spacers arranged around the first semiconductor chip on the substrate, wherein a second semiconductor chip and an adhesive film are arranged on the structure such that the adhesive film is interposed between the structure and the second semiconductor chip. The adhesive film is heat-cured, thereby bonding the second semiconductor chip to the structure. Includes, The adhesive film is the semiconductor adhesive film described in any one of claims 1 to 6. A method for manufacturing semiconductor devices.

11. The method according to claim 10, wherein, after the adhesive film has been heat-cured, the height of the spacer from the substrate is greater than the height of the first semiconductor chip from the substrate.

12. The method according to claim 10 or 11, wherein the adhesive film is heat-cured so that it is in contact with the first semiconductor chip.

13. The method according to any one of claims 10 to 12, further comprising forming a sealing layer that seals the first semiconductor chip and the second semiconductor chip.

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