TW202037696A - Filmy adhesive, adhesive sheet, semiconductor device, and method for manufacturing same - Google Patents

Abstract

The present invention discloses a filmy adhesive for bonding a semiconductor element and a support member on which the semiconductor element is mounted. The filmy adhesive contains a heat-curable resin component and a labelling agent.

Description

Film adhesive, adhesive sheet, semiconductor device and manufacturing method thereof

The invention relates to a film adhesive, an adhesive sheet, a semiconductor device and a manufacturing method thereof.

In recent years, stacked multi-chip packages (MCP) in which semiconductor elements (semiconductor chips) are stacked in multiple stages have become popular, and they are mounted in the form of memory semiconductor packages for mobile phones and mobile audio devices. . In addition, with the multi-functionalization of mobile phones and the like, the speed, density, and integration of semiconductor packaging are also advancing. Along with this, the use of copper as a wiring material for semiconductor chip circuits has achieved speedups. In addition, from the viewpoint of improving the reliability of connection to a complicated mounting substrate and promoting heat removal from the semiconductor package, a lead frame using copper as a raw material is being used.

However, from the viewpoint of copper's corrosion-prone characteristics and cost reduction, the coating material for ensuring the insulation of the circuit surface also tends to be simplified, and therefore it is difficult for semiconductor packages to ensure electrical properties. Particularly, in a semiconductor package in which a multi-stage semiconductor wafer is stacked, copper ions generated by corrosion move inside the adhesive, which tends to cause electrical signal loss in the semiconductor wafer or between the semiconductor wafer and the semiconductor wafer.

In addition, from the viewpoint of higher functionality, semiconductor elements are often connected to complex mounting substrates. In order to improve connection reliability, there is a tendency that a lead frame made of copper is preferred. Even in this case, there are cases where the loss of electrical signals caused by copper ions generated from the lead frame becomes a problem.

Furthermore, in a semiconductor package using a member made of copper as a raw material, copper ions are generated from the member, and there is a high possibility of causing electrical defects, and sometimes it is not possible to obtain sufficient resistance to a Highly Accelerated Stress Test (HAST). ) Sex.

From the viewpoint of preventing the loss of electrical signals, etc., an adhesive agent that captures copper ions generated in a semiconductor package is being studied. For example, Patent Document 1 discloses an adhesive sheet for semiconductor device manufacturing, including: a thermoplastic resin having an epoxy group and no carboxyl group; and an organic complex forming compound having a ring atom containing tertiary nitrogen atoms The heterocyclic compound and the cation to form a complex. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2013-026566

[The problem to be solved by the invention] However, with regard to the conventional adhesive, it is not sufficient to suppress the disadvantages associated with the movement of copper ions in the adhesive, and there is still room for improvement.

Therefore, the main object of the present invention is to provide a film-like adhesive that can sufficiently suppress the defects associated with the movement of copper ions in the adhesive. [Means to solve the problem]

The inventors of the present invention conducted diligent studies and found that the use of a leveling agent can sufficiently suppress the disadvantages associated with the movement of copper ions in the adhesive, and completed the present invention.

One aspect of the present invention provides a film-like adhesive, which is a film-like adhesive for bonding a semiconductor element to a support member on which the semiconductor element is mounted, and the film-like adhesive contains a thermosetting resin component and a leveling agent.

The reason why the movement of copper ions in the adhesive can be sufficiently suppressed by using the leveling agent is not necessarily certain, but the inventors believe that the reason is that the leveling agent is interposed in the surface layer of the adhesive to suppress the adhesion. Intake of copper ions in the surface layer of the agent.

The leveling agent may be a compound having a silicone structure.

The thermosetting resin component may include thermosetting resin, hardener, and acrylic rubber.

The thickness of the film adhesive may be 50 μm or less.

Another aspect of the present invention provides an adhesive sheet, including: a substrate; and the film-like adhesive disposed on one side of the substrate. The substrate may be a dicing tape.

Another aspect of the present invention provides a semiconductor device, including: a semiconductor element; a supporting member that mounts the semiconductor element; and a bonding member disposed between the semiconductor element and the supporting member to bond the semiconductor element to the supporting member; The cured product of the film-like adhesive. The supporting member may include a member using copper as a raw material.

Another aspect of the present invention provides a method of manufacturing a semiconductor device, including a step of bonding a semiconductor element and a supporting member using the film-like adhesive.

Yet another aspect of the present invention provides a method of manufacturing a semiconductor device, including: attaching the film-like adhesive of the adhesive sheet to a semiconductor wafer; and cutting the semiconductor wafer with the film-like adhesive attached A step of producing a plurality of singulated semiconductor devices with a film-like adhesive; and a step of bonding the semiconductor devices with a film-like adhesive to a supporting member. The method of manufacturing the semiconductor device may further include a step of heating the semiconductor element with the film-like adhesive attached to the support member using a reflow furnace. [Effects of the invention]

According to the present invention, it is possible to provide a film-like adhesive agent capable of sufficiently suppressing problems associated with the movement of copper ions in the adhesive agent. In addition, according to the present invention, it is possible to provide an adhesive sheet and a semiconductor device using such a film-like adhesive. Furthermore, according to the present invention, it is possible to provide a method of manufacturing a semiconductor device using a film-like adhesive or an adhesive sheet.

Hereinafter, the embodiments of the present invention will be described while referring to the drawings as appropriate. However, the present invention is not limited to the following embodiments. In the following embodiments, unless otherwise noted, its constituent elements (including steps, etc.) are not essential. The size of the component elements in each figure is conceptual, and the relative size of the component elements is not limited to that shown in each figure.

The same applies to the numerical values and ranges in this specification, and the present invention is not limited. In this specification, the numerical range indicated by "～" means a range that includes the numerical values described before and after "～" as the minimum and maximum values, respectively. Within the numerical range described in this specification step by step, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of the numerical range described in another step. In addition, within the numerical range described in this specification, the upper limit or lower limit of the numerical range may be replaced with the values shown in the examples.

In this specification, (meth)acrylate refers to acrylate or methacrylate corresponding thereto. The same applies to other similar expressions such as (meth)acrylic acid group and (meth)acrylic acid copolymer.

The film adhesive of one embodiment is a film adhesive for bonding a semiconductor element and a support member on which the semiconductor element is mounted, and the film adhesive contains a thermosetting resin component and a leveling agent.

The film adhesive can be obtained by molding an adhesive composition containing (A) a thermosetting resin component and (B) a leveling agent into a film. The film-like adhesive and the adhesive composition may be in a semi-cured (B-stage) state and can be in a fully cured (C-stage) state after the curing treatment.

In one embodiment, the (A) thermosetting resin component may include (A1) thermosetting resin, (A2) curing agent, and (A3) elastomer.

(A1) Ingredients: thermosetting resin From the viewpoint of adhesiveness, the component (A1) may be an epoxy resin. The epoxy resin can be used without particular limitation as long as it has an epoxy group in the molecule. As the epoxy resin, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, Bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin, stilbene type epoxy resin, epoxy resin containing triazine skeleton, epoxy resin containing fluorene skeleton, triphenol methane type ring Polycyclic aromatic diglycidols such as oxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, polyfunctional phenols, anthracene, etc. Ether compounds, etc. These can be used alone or in combination of two or more. Among these, in terms of the viscosity and flexibility of the film, the component (A1) may be a cresol novolac type epoxy resin, a phenol novolac type epoxy resin, a bisphenol F type epoxy resin, or a double Phenolic A type epoxy resin.

The epoxy equivalent of the epoxy resin is not particularly limited, and can be 90 g/eq to 300 g/eq or 110 g/eq to 290 g/eq. If the epoxy equivalent of the epoxy resin is within such a range, the bulk intensity of the film adhesive tends to be maintained while ensuring fluidity.

(A2) Ingredients: Hardener The component (A2) may be a phenol resin that can be a hardener for epoxy resin. The phenol resin can be used without particular limitation as long as it has a phenolic hydroxyl group in the molecule. Examples of phenol resins include phenols such as phenol, cresol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and/or α- Novolac type phenol resin obtained by condensation or co-condensation of naphthols, β-naphthol, dihydroxynaphthalene and other naphthols with formaldehyde and other compounds having aldehyde groups under acidic catalysts; from allylated bisphenol A, Allylated bisphenol F, allylated naphthalenediol, phenol novolac, phenol and other phenols and/or naphthols and dimethoxypara-xylene or bis(methoxymethyl)biphenyl Synthetic phenol aralkyl resin, naphthol aralkyl resin, etc. These can be used alone or in combination of two or more. Among these, the phenol resin phenol resin may be a phenol novolak type phenol resin or a naphthol aralkyl resin.

The hydroxyl equivalent of the phenol resin can be 70 g/eq or more or 70 g/eq to 300 g/eq. If the hydroxyl equivalent of the phenol resin is 70 g/eq or more, there is a tendency to further increase the storage elastic coefficient of the film. If the hydroxyl equivalent of the phenol resin is 300 g/eq or less, it can prevent the generation of foaming, outgassing, etc. The undesirable situation caused.

From the viewpoint of curability, the ratio of epoxy equivalent of epoxy resin to hydroxyl equivalent of phenol resin (epoxy equivalent of epoxy resin/hydroxy equivalent of phenol resin) can be 0.30/0.70～0.70/0.30, 0.35/ 0.65～0.65/0.35, 0.40/0.60～0.60/0.40 or 0.45/0.55～0.55/0.45. If the equivalent ratio is 0.30/0.70 or more, there is a tendency that more sufficient curability can be obtained. If the equivalent ratio is 0.70/0.30 or less, the viscosity can be prevented from becoming excessively high, and more sufficient fluidity can be obtained.

Relative to the total mass of (A) component 100 parts by mass, the total content of (A1) component and (A2) component can be 5 parts by mass to 50 parts by mass, 10 parts by mass to 40 parts by mass, or 15 parts by mass to 30 parts by mass . If the total content of the (A1) component and the (A2) component is 5 parts by mass or more, the crosslinking tends to increase the modulus of elasticity. If the total content of the (A1) component and (A2) component is 50 parts by mass or less, there is a tendency that film handling properties can be maintained.

(A3) Ingredients: elastomer (A3) A component may be acrylic rubber which has a structural unit derived from (meth)acrylate as a main component. Regarding the content of the (meth)acrylate-derived structural unit in the component (A3), based on the total amount of the structural unit, for example, it may be 70% by mass or more, 80% by mass or more, or 90% by mass or more. Acrylic rubber may contain a structural unit derived from (meth)acrylate having crosslinkable functional groups such as epoxy groups, alcoholic or phenolic hydroxyl groups, and carboxyl groups.

(A3) The glass transition temperature (Tg) of the component can be -50℃～50℃ or -30℃～30℃. If the Tg of the component (A3) is -50°C or higher, it tends to prevent the flexibility of the adhesive from becoming too high. This makes it easy to cut the film-like adhesive during wafer dicing, and prevents the generation of burrs. If the Tg of the component (A3) is 50° C. or less, there is a tendency that a decrease in the flexibility of the adhesive can be suppressed. With this, when the film-like adhesive is attached to the wafer, it tends to be easy to fill the void sufficiently. In addition, it is possible to prevent chipping during dicing due to a decrease in the adhesiveness of the wafer. Here, the glass transition temperature (Tg) refers to a value measured using a differential scanning calorimeter (Differential Scanning Calorimeter, DSC) (for example, manufactured by Rigaku Co., Ltd., Thermo Plus 2).

(A3) The weight average molecular weight (Mw) of the component can be 100,000 to 3 million or 200,000 to 2 million. When the Mw of the component (A3) is in such a range, the film formability, the strength in the film form, the flexibility, the viscosity, etc. can be appropriately controlled, the reflow properties are excellent, and the embedding properties can be improved. Here, Mw refers to a value obtained by measuring by Gel Permeation Chromatography (GPC) and using a calibration curve based on standard polystyrene.

Examples of commercially available products of the component (A3) include SG-P3, SG-80H, and HTR-860P-3CSP (all manufactured by Nagase ChemteX Co., Ltd.).

The content of the (A3) component may be 50 parts by mass to 95 parts by mass, 60 parts by mass to 90 parts by mass, or 70 parts by mass to 85 parts by mass relative to 100 parts by mass of the total mass of the component (A). If the content of the component (A3) is within such a range, there is a tendency that the movement (permeation) of copper ions in the adhesive can be further sufficiently suppressed.

In other embodiments, the (A) thermosetting resin component may also be an elastomer containing crosslinkable functional groups such as epoxy groups, alcoholic or phenolic hydroxyl groups, and carboxyl groups, and those that can react with crosslinkable functional groups. Hardener. As a combination of an elastomer having a crosslinkable functional group and a curing agent capable of reacting with the crosslinkable functional group, for example, a combination of an acrylic rubber having an epoxy group and a phenol resin can be cited.

(B) Ingredient: Leveling agent (surface adjusting agent) When the film-like adhesive contains the component (B), the incorporation of copper ions in the surface layer of the adhesive can be suppressed. The component (B) is not particularly limited as long as the surface tension of the film-like adhesive can be adjusted, and it may be a compound having a silicone structure (in other words, polysiloxane or silicone). Examples of such (B) component include polysiloxane (silicone) such as polyether modification, polyester modification, aralkyl modification, and phenyl modification. These can be used alone or in combination of two or more.

As commercially available products of compounds having a siloxane structure, for example, BYK-307, BYK-310, BYK-333, BYK-377, BYK-378 (all are trade names, BYK-CHEMIE JAPAN) Co., Ltd.), KF-945, KF-6204 (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

The content of the (B) component can be 0.1 to 5.0 parts by mass, 0.15 to 2.0 parts by mass, or 0.2 to 1.5 parts by mass relative to 100 parts by mass of the total mass of the (A) component. If the content of the component (B) is 0.1 parts by mass or more, there is a tendency that the intake of copper ions in the surface layer of the adhesive can be further suppressed.

The film adhesive (adhesive composition) may further contain (C) an inorganic filler, (D) a coupling agent, (E) a hardening accelerator, and the like.

(C) Ingredient: Inorganic filler As the (C) component, 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, silicon dioxide, etc. These can be used alone or in combination of two or more. Among these, from the viewpoint of adjusting the melt viscosity, the component (C) may be silica. (C) The shape of the component is not particularly limited, and may be spherical.

From the viewpoint of fluidity, the average particle size of the component (C) may be 0.01 μm to 1 μm, 0.01 μm to 0.8 μm, or 0.03 μm to 0.5 μm. Here, the average particle size refers to a value obtained by conversion based on the Brunauer-Emmett-Teller (BET) specific surface area.

The content of the (C) component can be 0.1 to 50 parts by mass, 0.1 to 30 parts by mass, or 0.1 to 20 parts by mass relative to 100 parts by mass of the total mass of the (A) component.

(D) Ingredient: Coupling agent (D) The component can be a silane coupling agent. As the silane coupling agent, for example, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, 3-phenylaminopropyltrimethoxysilane, 3-(2-amine) Ethyl)aminopropyl trimethoxysilane and the like. These can be used alone or in combination of two or more.

(E) Ingredient: Hardening accelerator (E) The component is not particularly limited, and ordinary users can be used. As the (E) component, for example, imidazoles and their derivatives, organophosphorus compounds, secondary amines, tertiary amines, quaternary ammonium salts, etc. may be mentioned. These can be used alone or in combination of two or more. Among these, from the viewpoint of reactivity, the component (E) may be imidazoles and derivatives thereof.

Examples of imidazoles include 2-methylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-cyanoethyl-2-methylimidazole Wait. These can be used alone or in combination of two or more.

The film adhesive (adhesive composition) may further contain other components. Examples of other components include pigments, ion scavengers, and antioxidants.

The content of (D) component, (E) component, and other components may be 0 to 30 parts by mass relative to 100 parts by mass of the total mass of (A) component.

Fig. 1 is a schematic cross-sectional view showing an embodiment of a film adhesive. The film-like adhesive 1 (adhesive film) shown in FIG. 1 is formed by molding an adhesive composition into a film shape. The film adhesive 1 may be in a semi-cured (B-stage) state. Such a film-like adhesive 1 can be formed by applying an adhesive composition to a support film. In the case of using the varnish of the adhesive composition (adhesive varnish), the film-like adhesive 1 can be formed by the following method: (A) component and (B) component and other components added as necessary in the solvent In the medium mixing, the mixed liquid is mixed or kneaded to prepare an adhesive varnish, the adhesive varnish is applied to the support film, and the solvent is heated to dry and removed.

The supporting film is not particularly limited as long as it can withstand the heating and drying. For example, it may be a polyester film, a polypropylene film, a polyethylene terephthalate film, a polyimide film, and a polyetherimide film. , Polyether naphthalate film, polymethylpentene film, etc. The support film can be a multilayer film formed by combining two or more types, or the surface can be treated with a release agent such as silicone type or silica type. The thickness of the support film may be, for example, 10 μm to 200 μm or 20 μm to 170 μm.

Mixing or kneading can be performed using a disperser such as a general mixer, a crusher, a three-rod roll mill, or a ball mill, and these can be appropriately combined.

The solvent used for preparing the adhesive varnish can be used without limitation as long as it can uniformly dissolve, knead, or disperse each component. Examples of such solvents include: ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; dimethylformamide, dimethylacetamide, and N-methyl Pyrolidone, toluene, xylene, etc. In terms of fast drying speed and low price, the solvent may be methyl ethyl ketone, cyclohexanone, or the like.

As a method of applying the adhesive varnish to the support film, a known method can be used, and examples thereof include a knife coating method, a roll coating method, a spray coating method, a gravure coating method, a bar coating method, and a curtain coating method. The conditions for heating and drying are not particularly limited as long as the solvent used is sufficiently volatilized, and it can be performed by heating at 50°C to 150°C for 1 minute to 30 minutes.

The thickness of the film adhesive may be 50 μm or less. If the thickness of the film-like adhesive is 50 μm or less, the distance between the semiconductor element and the support member on which the semiconductor element is mounted becomes shorter, and therefore there is a tendency that defects caused by copper ions are likely to occur. The film-like adhesive of this embodiment can sufficiently suppress the movement (permeation) of copper ions in the adhesive, and therefore the thickness can be made 50 μm or less. The thickness of the film adhesive 1 may be 40 μm or less, 30 μm or less, 20 μm or less, or 15 μm or less. The lower limit of the thickness of the film-like adhesive 1 is not particularly limited, and it can be set to 1 μm or more, for example.

The copper ion penetration time of the film adhesive 1 (ie, the cured product of the film adhesive) in the fully cured (C stage) state can be 200 minutes or more, 200 minutes or more, 300 minutes or more, or 500 minutes or more. . Defects caused by copper ions tend to occur during high-temperature processing such as the reflow step. Therefore, by the fully cured (C stage) state for more than 200 minutes, it can be predicted that it is less likely to produce defects caused by copper ions.

Fig. 2 is a schematic cross-sectional view showing an embodiment of an adhesive sheet. The adhesive sheet 100 shown in FIG. 2 includes: a base material 2; and a film-like adhesive 1 disposed on the base material 2. Fig. 3 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. The adhesive sheet 110 shown in FIG. 3 includes: a substrate 2; a film-like adhesive 1 provided on the substrate 2; and a cover film 3 provided on the opposite of the substrate 2 of the film-like adhesive 1 On one side.

The substrate 2 is not particularly limited, and may be a substrate film. The base film may be the same as the support film.

The cover film 3 is used to prevent damage or contamination of the film adhesive, and may be, for example, a polyethylene film, a polypropylene film, a surface release agent treatment film, or the like. The thickness of the cover film 3 may be, for example, 15 μm to 200 μm or 70 μm to 170 μm.

The adhesive sheet 100 and the adhesive sheet 110 can be formed by applying an adhesive composition to a base film in the same way as the method of forming the film-like adhesive. The method of applying the adhesive composition to the substrate 2 may be the same as the method of applying the adhesive composition to the support film.

The adhesive sheet 110 can be obtained by further laminating the cover film 3 on the film-like adhesive 1.

The adhesive sheet 100 and the adhesive sheet 110 may also be formed using a film-like adhesive produced in advance. In this case, the adhesive sheet 100 can be formed by laminating using a roll laminator or a vacuum laminator under prescribed conditions (for example, room temperature (20° C.) or heated state). The subsequent sheet 100 can be continuously manufactured, and in terms of excellent efficiency, it can also be formed by using a roll laminator in a heated state.

Another embodiment of the adhesive sheet is a die-cut and die-bonded integrated adhesive sheet in which the substrate 2 is a dicing tape. If a die-cut die-bonding integrated adhesive sheet is used, the lamination step for the semiconductor wafer is one time, so the efficiency of the work can be achieved.

Examples of the dicing tape include plastic films such as polytetrafluoroethylene film, polyethylene terephthalate film, polyethylene film, polypropylene film, polymethylpentene film, and polyimide film. In addition, the dicing tape can also be subjected to surface treatments such as primer coating, ultraviolet (UV) treatment, corona discharge treatment, grinding treatment, and etching treatment as needed. The cutting tape can be adhesive. Such a cutting tape may be obtained by imparting adhesiveness to the plastic film, or may be obtained by providing an adhesive layer on one side of the plastic film. The adhesive layer can be either a pressure sensitive type or a radiation curable type, as long as it has sufficient adhesive force not to scatter the semiconductor element during dicing, and has a degree that does not damage the semiconductor element in the subsequent pickup step of the semiconductor element There are no special restrictions on those with low adhesion, and the previously known ones can be used.

From the viewpoint of economy and film operability, the thickness of the dicing tape may be 60 μm to 150 μm or 70 μm to 130 μm.

As such a die-cut and die-bonded integrated adhesive sheet, for example, those having the structure shown in FIG. 4, those having the structure shown in FIG. 5, and the like can be cited. Fig. 4 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. Fig. 5 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. The adhesive sheet 120 shown in FIG. 4 includes a dicing tape 7, an adhesive layer 6 and a film adhesive 1 in this order. The adhesive sheet 130 shown in FIG. 5 includes: a dicing tape 7; and a film-like adhesive 1 disposed on the dicing tape 7.

The adhesive sheet 120 can be obtained, for example, by disposing the adhesive layer 6 on the dicing tape 7, and then laminating the film-like adhesive 1 on the adhesive layer 6. The adhesive sheet 130 can be obtained, for example, by bonding the dicing tape 7 and the film-like adhesive 1 together.

The film adhesive and the adhesive sheet may be those used in the manufacture of semiconductor devices, or they may be used in the manufacture of semiconductor devices including the following steps: the film adhesive and the dicing tape are attached at 0°C to 90°C After semiconductor wafers or singulated semiconductor devices (semiconductor wafers) are divided by rotating knife, laser or elongation to obtain semiconductor devices with film adhesive, the film adhesive The semiconductor components are attached to organic substrates, lead frames or other semiconductor components.

Examples of semiconductor wafers include single crystal silicon, polycrystalline silicon, various ceramics, and compound semiconductors such as gallium arsenide.

Film adhesives and adhesive sheets can be used to connect semiconductor components such as integrated circuits (IC) and large scale integrated circuits (LSI) with lead frames such as 45 alloy lead frames and copper lead frames; Plastic films made of polyimide resin, epoxy resin, etc.; those made by impregnating glass nonwovens and other substrates with plastics such as polyimide resin, epoxy resin, etc. and then hardening them; supporting members for mounting semiconductors such as ceramics such as alumina, etc. Adhesive for bonding crystal bonding.

Film adhesives and adhesive sheets can also be preferably used as adhesives for bonding semiconductor devices and semiconductor devices in a stacked package (Stacked-PKG) in which a plurality of semiconductor devices are stacked. In this case, the other semiconductor element becomes a support member on which the semiconductor element is mounted.

Film-like adhesives and adhesive sheets can also be used, for example, as a protective sheet for protecting the back surface of a semiconductor element of a flip chip type semiconductor device, and for protecting the surface of the semiconductor element of a flip chip type semiconductor device and the adherend. Sealing sheet for sealing between.

The semiconductor device manufactured using the film-like adhesive will be specifically described using the drawings. Furthermore, in recent years, semiconductor devices of various structures have been proposed, and the use of the film-like adhesive of this embodiment is not limited to semiconductor devices of the structure described below.

Fig. 6 is a schematic cross-sectional view showing an embodiment of a semiconductor device. The semiconductor device 200 shown in FIG. 6 includes: a semiconductor element 9; a support member 10 on which the semiconductor element 9 is mounted; and an adhesive member (cured product 1c of a film-like adhesive), which is provided between the semiconductor element 9 and the support member 10, and The semiconductor element 9 is bonded to the support member 10. The connection terminal (not shown) of the semiconductor element 9 is electrically connected to an external connection terminal (not shown) via a wire 11 and is sealed by a sealing material 12.

Fig. 7 is a schematic cross-sectional view showing another embodiment of a semiconductor device. In the semiconductor device 210 shown in FIG. 7, the semiconductor element 9a of the first stage is connected to the supporting member 10 with the terminal 13 formed by the bonding member (the cured product 1c of the film-like adhesive), and the semiconductor element 9a of the first stage is The second-stage semiconductor element 9b is further connected to the element 9a by the bonding member (the cured product 1c of the film-like adhesive). The connection terminals (not shown) of the semiconductor element 9 a of the first stage and the semiconductor element 9 b of the second stage are electrically connected to external connection terminals via wires 11 and are sealed by a sealing material 12. In this way, the film adhesive of this embodiment can also be suitably used for a semiconductor device having a structure where a plurality of semiconductor elements are stacked.

The semiconductor device (semiconductor package) shown in FIGS. 6 and 7 can be obtained, for example, by making a film-like adhesive interposed between the semiconductor element and the supporting member or between the semiconductor element and the semiconductor element, and the These are heated and compressed to connect the two together, and thereafter, if necessary, go through a wire bonding step, a sealing step using a sealing material, a heat melting step including reflow of solder, and the like. The heating temperature in the thermal compression bonding step is usually 20°C to 250°C, the load is usually 0.1 N to 200 N, and the heating time is usually 0.1 second to 300 seconds.

As a method of making the film-like adhesive intervene between the semiconductor element and the supporting member or between the semiconductor element and the semiconductor element, as described above, the semiconductor element with the film-like adhesive is prepared in advance and then attached For supporting members or semiconductor devices.

The supporting member may be a member containing copper as a raw material. In the semiconductor device of this embodiment, the semiconductor element and the support member are bonded by the cured product 1c of the film-like adhesive. Therefore, even when a member made of copper is used as a constituent member of the semiconductor device, it can be reduced. The influence of copper ions generated by the component can sufficiently suppress the occurrence of electrical defects caused by copper ions.

Here, as a member using copper as a raw material, for example, a lead frame, wiring, a wire, a heat radiation material, etc. can be cited. Even when copper is used for any member, the influence of copper ions can be reduced.

Next, an embodiment of a method of manufacturing a semiconductor device when the die-cut die-bonding integrated adhesive sheet shown in FIG. 4 is used is described. In addition, the method of manufacturing a semiconductor device using a die-cut die-bonding integrated adhesive sheet is not limited to the method of manufacturing a semiconductor device described below.

First, the semiconductor wafer is crimped to the film-like adhesive 1 in the adhesive sheet 200 (die-cut and die-bonded integrated adhesive sheet), and then held and fixed (mounting step). This step can be performed while pressing with a pressing mechanism such as a pressure contact roller.

Then, the semiconductor wafer is diced. Thereby, the semiconductor wafer is cut to a predetermined size, thereby manufacturing a plurality of singulated semiconductor elements (semiconductor wafers) with a film-like adhesive. For example, it can be cut from the circuit surface side of the semiconductor wafer according to a conventional method. In addition, in this step, for example, it is possible to use: a cutting method called full cutting that cuts into the dicing tape; a method of cutting a semiconductor wafer by cutting half of the cut and cooling and stretching; and using a laser Cutting method, etc. The cutting device used in this step is not particularly limited, and a previously known one can be used.

In order to peel off the semiconductor element that is then fixed to the die-cut die-bonding integrated adhesive sheet, the semiconductor element is picked up. The picking method is not particularly limited, and various conventionally known methods can be adopted. For example, a method of using a thimble to lift each semiconductor element from the side of the die-cutting and die-bonding integrated adhesive sheet, and using a pickup device to pick up the lifted semiconductor element, etc.

Here, when the adhesive layer is a radiation (for example, ultraviolet) curing type, the adhesive layer is irradiated with radiation and then picked up. Thereby, the adhesive force of the adhesive layer with respect to the film-like adhesive decreases, and the semiconductor element is easily peeled off. As a result, it is possible to pick up the semiconductor element without damaging it.

Then, the semiconductor element with the film-like adhesive formed by dicing is attached to the supporting member for mounting the semiconductor element via the diaphragm-like adhesive. Then it can be done by crimping. The crystal bonding conditions are not particularly limited, and can be appropriately set as needed. Specifically, for example, it can be performed within the range of a die bonding temperature of 80°C to 160°C, a bonding load of 5 N to 15 N, and a bonding time of 1 second to 10 seconds.

If necessary, a step of thermally curing the film-like adhesive may also be provided. The film-like adhesive that bonds the support member and the semiconductor element through the bonding step is thermally cured, thereby enabling stronger bonding and fixing. In the case of thermal hardening, pressure can be applied simultaneously to harden. The heating temperature in this step can be appropriately changed according to the constituent components of the film adhesive. The heating temperature can be, for example, 60°C to 200°C. Furthermore, it can be performed while changing the temperature or pressure step by step.

Then, a wire bonding step is performed to electrically connect the tip of the terminal portion (inner lead) of the support member and the electrode pad on the semiconductor element with a bonding wire. As the bonding wire, for example, a gold wire, an aluminum wire, a copper wire, etc. can be used. The temperature during wire bonding may be in the range of 80°C to 250°C or 80°C to 220°C. The heating time can be several seconds to several minutes. In the state of heating in the above-mentioned temperature range, the wire can be connected by combining the vibration energy of the ultrasonic wave and the crimping energy of the application of pressure.

Then, a sealing step of sealing the semiconductor element with a sealing resin is performed. This step is performed to protect the semiconductor element or the bonding wire mounted on the support member. The present invention is carried out by molding a resin for sealing with a mold. As the sealing resin, for example, an epoxy resin may be used. By embedding the substrate and residue by the heat and pressure during sealing, it is possible to prevent peeling caused by bubbles at the bonding interface.

Then, in the post-curing step, the sealing resin that was insufficiently cured in the sealing step is completely cured. Even in the case where the film-like adhesive is not thermally cured in the sealing step, the film-like adhesive may be thermally cured at the same time as the curing of the sealing resin in this step to perform adhesive fixation. The heating temperature in this step can be appropriately set according to the type of sealing resin, for example, it can be in the range of 165°C to 185°C, and the heating time can be about 0.5 to 8 hours.

Then, the semiconductor element with the film-like adhesive attached to the support member is heated using a reflow furnace. In this step, a resin-sealed semiconductor device may also be mounted on the upper surface of the support member. As a method of surface mounting, for example, after preliminarily supplying solder on a printed wiring board, it is heated and melted by warm air or the like, and soldering is performed by reflow soldering. As a heating method, hot air reflow, infrared reflow, etc. are mentioned, for example. In addition, the heating method may be a method of heating the whole or a method of heating a part. The heating temperature may be in the range of 240°C to 280°C, for example.

In the case of laminating semiconductor elements into multiple layers, the thermal history such as the wire bonding step increases, and the effect on peeling due to bubbles present at the interface between the film adhesive and the semiconductor element increases. However, the film-like adhesive of the present embodiment has a tendency to decrease cohesive force and improve embedding properties by using specific acrylic rubber. Therefore, bubbles are not easily caught in the semiconductor device, the bubbles in the sealing step can be easily diffused, and peeling caused by the bubbles at the bonding interface can be prevented. [Example]

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these.

[Production of film adhesive] (Example 1 to Example 3 and Comparative Example 1) ＜Preparation of adhesive varnish＞ Based on the product name and composition ratio (unit: parts by mass) shown in Table 1, to a composition containing epoxy resin as (A1) thermosetting resin, phenol resin as (A2) hardener, and (C) inorganic filler Add cyclohexanone and stir and mix. To this was added acrylic rubber as (A3) elastomer shown in Table 1 and stirred, and then (D) coupling agent, (E) hardening accelerator and (B) leveling agent shown in Table 1 were added, and Stir until the components become uniform, thereby preparing an adhesive varnish. In addition, the numerical value of (A3) component and (C) component shown in Table 1 means the mass part of solid content.

(A) Thermosetting resin component (A1) Thermosetting resin (A1-1) YDCN-700-10 (trade name, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., o-cresol novolac epoxy resin, epoxy equivalent: 209 g/eq) (A2) Hardener (A2-1) PSM4326 (trade name, manufactured by Qunrong Chemical Industry Co., Ltd., phenol novolac resin, hydroxyl equivalent: 105 g/eq) (A3) Elastomer (A3-1) SG-P3 (trade name, manufactured by Nagase ChemteX Co., Ltd., methyl ethyl ketone solution of acrylic rubber with epoxy group, weight average molecular weight of acrylic rubber: 850,000)

(B) Leveling agent (B1) BYK-333 (trade name, manufactured by BYK-CHEMIE JAPAN Co., Ltd., polyether modified polydimethylsiloxane)

(C) Inorganic filler (C1) SC2050-HLG (trade name, manufactured by Admatechs Co., Ltd., silica filler dispersion, average particle size 0.50 μm)

(D) Coupling agent (D1) A-189 (trade name, manufactured by Nippon Unicar Co., Ltd., γ-mercaptopropyltrimethoxysilane) (D2) A-1160 (trade name, manufactured by Nippon Unicar Co., Ltd., γ-ureidopropyltriethoxysilane)

(E) Hardening accelerator (E1) 2PZ-CN (trade name, manufactured by Shikoku Chemical Industry Co., Ltd., 1-cyanoethyl-2-phenylimidazole)

＜Production of film adhesive＞ The produced adhesive varnish was filtered with a 100 mesh (mesh) filter and vacuum degassed. A polyethylene terephthalate (PET) film with a thickness of 38 μm and subjected to a mold release treatment was prepared as a base film, and an adhesive varnish after vacuum degassing was applied on the PET film. The applied adhesive varnish was heated and dried in two stages at 90°C for 5 minutes and then at 130°C for 5 minutes to obtain the film-like adhesives of Examples 1 to 3 and Comparative Example 1 in the B-stage state Agent. In the film-like adhesive, the thickness was adjusted to 10 μm according to the coating amount of the adhesive varnish.

[Measurement of copper ion penetration time] ＜Preparation of A solution＞ Dissolve 2.0 g of anhydrous copper (II) sulfate in 1020 g of distilled water, and stir until the copper sulfate is completely dissolved, thereby preparing a copper sulfate aqueous solution with a copper ion concentration of 500 mg/kg in terms of Cu element. Let the obtained copper sulfate aqueous solution be A liquid.

＜Preparation of B solution＞ Dissolve 1.0 g of anhydrous sodium sulfate in 1000 g of distilled water, and stir until the sodium sulfate is completely dissolved. To this, 1000 g of N-Methyl-2-Pyrrolidone (N-Methyl-2-Pyrrolidone, NMP) was further added and stirred. After that, air cooling was performed until it reached room temperature to obtain a sodium sulfate aqueous solution. Let the obtained solution be B solution.

＜Measurement of copper ion transmission time＞ The film adhesives of Examples 1 to 3 and Comparative Example 1 in the B-stage state were further heated and dried at 170°C for 1 hour to produce Examples 1 to 3 and Comparative Example 1 in the C-stage state The film-like adhesive. The film-like adhesives (thickness: 10 μm) of Examples 1 to 3 and Comparative Example 1 in the C-stage state were cut into circular shapes with a diameter of approximately 3 cm. Next, prepare two silicon gaskets with a thickness of 1.5 mm, an outer diameter of about 3 cm, and an inner diameter of 1.8 cm. The film-shaped adhesive cut into a circle is clamped by two silicon gasket sheets, and the silicon gasket sheet is clamped by the flanges of two glass cells with a volume of 50 mL, and fixed with rubber bands.

Then, after pouring 50 g of liquid A into one of the glass-made cells, pouring 50 g of liquid B into the other glass-made cell. Insert Mars Carbon (manufactured by STAEDTLER Co., Ltd., Φ2 mm/130 mm) as a carbon electrode in each unit. Set the A liquid side as the anode and the B liquid side as the cathode, and connect the anode to a DC power supply (manufactured by A&D Co., Ltd., DC power supply device AD-9723D). In addition, the cathode and the DC power supply are connected in series via an ammeter (manufactured by Sanwa Electric Meter Co., Ltd., digital multimeter (Degital multimeter) PC-720M). At room temperature, a voltage was applied at an applied voltage of 24.0 V, and the current value measurement was started after the application. The measurement is performed until the current value exceeds 5 μA, and the time when the current value becomes 1 μA is defined as the copper ion transmission time. The results are shown in Table 1. In this evaluation, it can be said that the longer the transmission time, the more the movement (transmission) of copper ions can be suppressed.

[Measurement of the shear strength of the wafer after hardening] ＜Production of semiconductor devices＞ Prepare a dicing tape (manufactured by Hitachi Chemical Co., Ltd., thickness 110 μm), and attach the film adhesives (thickness 10 μm) of Examples 1 to 3 and Comparative Example 1 in the B-stage state to produce Die-cut and die-bonded integrated adhesive sheet with tape and film adhesive. A 400 μm-thick semiconductor wafer was laminated on the film adhesive side of the die-cut and die-bond integrated adhesive sheet at a platform temperature of 70°C to prepare a dicing sample.

A fully automatic microtome DFD-6361 (manufactured by DISCO Co., Ltd.) was used to cut the obtained cut sample. Regarding the cutting, it is carried out in a stepwise cutting method using two blades, and the cutting blades ZH05-SD3500-N1-xx-DD and ZH05-SD4000-N1-xx-BB (both DISCO) are used. Co., Ltd. manufacturing). The cutting conditions were set as the blade speed 4000 rpm, the cutting speed 50 mm/sec, and the wafer size 5 mm×5 mm. Regarding the cutting, the first stage of cutting is performed so that the semiconductor wafer remains about 200 μm, and then the second stage of dicing is performed so that the dicing tape makes a cut of about 20 μm.

Then, the semiconductor chip obtained by cutting is thermally compressed on a solder resist (Taiyo Holdings Co., Ltd., trade name: AUS-308). The crimping conditions were set to a temperature of 120°C, a time of 1 second, and a pressure of 0.1 MPa. Then, the sample obtained by crimping was put in a dryer and hardened at 170°C for 1 hour. Harden the semiconductor chip crimped to the solder resist, and use a universal bond tester (manufactured by Nordson Advance Technology Co., Ltd., trade name: Series 4000) while hooking the semiconductor chip Stretching is performed to measure the chip shear strength after hardening of the semiconductor chip and the solder resist. Regarding the measurement conditions, the platform temperature was set to 250°C. The results are shown in Table 1.

[Table 1] Comparative example 1 Example 1 Example 2 Example 3 (A) Ingredient (A1) (A1-1) 11 11 11 11 (A2) (A2-1) 6 6 6 6 (A3) (A3-1) 73 73 73 73 (B) Ingredients (B1) - 0.25 0.5 1.0 (C) Ingredients (C1) 8 8 8 8 (D) Ingredients (D1) 0.4 0.4 0.4 0.4 (D2) 1.2 1.2 1.2 1.2 (E) Ingredients (E1) 0.02 0.02 0.02 0.02 Copper ion penetration time (minutes) Phase C@1 μA 180 321 923 878 Shear strength of wafer after hardening (MPa) 250°C 2.0 2.0 2.0 2.0

As shown in Table 1, the film-like adhesives of Examples 1 to 3 are less permeable to copper ions than the film-like adhesives of Comparative Example 1. It is presumed that this is because the surface tension of the adhesive is lowered by the leveling agent, and the incorporation of copper ions in the surface layer of the adhesive can be suppressed.

From the above, it was confirmed that the film-like adhesive of the present invention can sufficiently suppress the disadvantages associated with the movement of copper ions in the adhesive.

1: Film adhesive 1c: Hardened product of film adhesive 2: substrate 3: cover film 6: Adhesive layer 7: Cutting tape 9, 9a, 9b: semiconductor components 10: Supporting member 11: Wire 12: Sealing material 13: Terminal 100, 110, 120, 130: Next film 200, 210: Semiconductor device

Fig. 1 is a schematic cross-sectional view showing an embodiment of a film adhesive. Fig. 2 is a schematic cross-sectional view showing an embodiment of an adhesive sheet. Fig. 3 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. Fig. 4 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. Fig. 5 is a schematic cross-sectional view showing another embodiment of the adhesive sheet. Fig. 6 is a schematic cross-sectional view showing an embodiment of a semiconductor device. Fig. 7 is a schematic cross-sectional view showing another embodiment of a semiconductor device.

1: Film adhesive

Claims (11)

A film-like adhesive, which is a film-like adhesive used to bond a semiconductor element to a support member on which the semiconductor element is mounted, and The film-like adhesive contains a thermosetting resin component and a leveling agent. The film adhesive according to claim 1, wherein the leveling agent is a compound having a silicone structure. The film-like adhesive according to claim 1 or 2, wherein the thermosetting resin component includes a thermosetting resin, a curing agent, and an elastomer. The film-like adhesive according to any one of claims 1 to 3, wherein the thickness of the film-like adhesive is 50 μm or less. A follow-up film, including: Substrate; and The film adhesive according to any one of claims 1 to 4 is provided on one side of the substrate. The adhesive sheet according to claim 5, wherein the substrate is a dicing tape. A semiconductor device including: Semiconductor components A supporting member that mounts the semiconductor element; and A subsequent member is provided between the semiconductor element and the supporting member, and the semiconductor element and the supporting member are bonded; and The adhesive member is a cured product of the film-like adhesive according to any one of claims 1 to 4. The semiconductor device according to claim 7, wherein the supporting member includes a member using copper as a raw material. A method of manufacturing a semiconductor device, which includes a step of bonding a semiconductor element and a supporting member using the film-like adhesive according to any one of claims 1 to 4. A method for manufacturing a semiconductor device includes: The step of attaching the film-like adhesive of the adhesive sheet described in claim 5 or claim 6 to a semiconductor wafer; A step of manufacturing a plurality of singulated semiconductor devices with a film adhesive by cutting the semiconductor wafer to which the film adhesive is attached; and The step of attaching the semiconductor element with the film-like adhesive to the supporting member. The method of manufacturing a semiconductor device according to claim 10, which further includes a step of heating the semiconductor element with the film-like adhesive attached to the support member using a reflow furnace.

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