JP2020072149A - Film glue for semiconductor, manufacturing method of semiconductor device and semiconductor device - Google Patents

Abstract

To provide film glue for semiconductor capable of improving connectibility and insulation reliability of semiconductor device.SOLUTION: Film glue 1 for semiconductor includes a first layer 2 composed of a first thermosetting adhesive containing a flux compound, and a second layer 3 provided on the first layer 2 and composed of a second thermosetting adhesive, and satisfies following conditions (A). Conditions (A): The film glue for semiconductor is heated for 60 minutes at 240°C under air atmosphere to obtain a cured product, which is pulverized to obtain a ground product. The ground product is passed through a Tyler sieve 200 mesh, a granular material 1 g passed through the sieve and ion-exchange water 40 g are mixed to obtain a blend, which is then boiled in a closed vessel for 48 hours under 2 atmospheres at 121°C, and when measuring chlorine ion concentration of extraction water obtained by removing the granular material from the boiled blend by ion chromatography method, the chlorine ion concentration of the extraction water is 2 mass ppm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a film adhesive for semiconductors, a method for manufacturing a semiconductor device, and a semiconductor device.

  Conventionally, a wire bonding method using a metal thin wire such as a gold wire has been widely applied for connecting a semiconductor chip and a substrate. On the other hand, in order to meet the demands for higher functionality, higher integration, higher speed, etc. of semiconductor devices, flip chips that directly connect the semiconductor chip and the substrate by forming conductive protrusions called bumps on the semiconductor chip or substrate. The connection method (FC connection method) is spreading.

  For example, regarding connection between a semiconductor chip and a substrate, a COB (Chip On Board) type connection method that is frequently used in BGA (Ball Grid Array), CSP (Chip Size Package), etc. also corresponds to the FC connection method. The FC connection method is also widely used for a COC (Chip On Chip) type connection method in which a connection portion (for example, a bump and a wiring) is formed on a semiconductor chip to connect the semiconductor chips.

  In addition, for packages that are strongly required to be further miniaturized, made thinner, and have higher functionality, chip stack type packages, POPs (Package On Package), TSVs (Throughhgh), in which chips are stacked using the above-described connection method to form multiple stages. -Silicon Via) and the like have begun to spread widely. Since such a stacking / multi-stage technology arranges semiconductor chips and the like in three dimensions, the package can be made smaller than the method of arranging in two dimensions. Further, since it is effective in improving the performance of semiconductors, reducing noise, reducing the mounting area, and saving power, it is drawing attention as a next-generation semiconductor wiring technology.

  By the way, as a main metal used for the connection portion (bump or wiring), for example, solder, tin, gold, silver, copper, nickel and the like can be mentioned, and a conductive material containing plural kinds of these is also used. .. On the connection surface of the connection part, the surface of the metal used for the connection part may be oxidized to form an oxide film, and impurities such as oxides may be attached to the surface of the metal. is there. If such impurities remain, it is feared that the connectivity and insulation reliability between the semiconductor chip and the substrate or between the two semiconductor chips will be deteriorated, and the merits of adopting the above-mentioned connection method will be impaired.

  As a method of suppressing the generation of these impurities, there is a method of coating the connection portion with an antioxidant film, which is known by OSP (Organic Solderability Preservatives) treatment and the like. However, this antioxidant film may cause a decrease in solder wettability during the connection process, a decrease in connection property, and the like.

  Therefore, as a method for removing the oxide film and impurities described above, a method using an adhesive film containing a flux agent has been proposed (see, for example, Patent Document 1).

International publication 2013/125086

  As described above, in the flip-chip package using the flip-chip connection method, higher functionality, higher integration, three-dimensionalization, etc. are being studied. Such flip chip packages are required to have further improved connectivity and insulation reliability.

  Therefore, an object of the present invention is to provide a semiconductor device having excellent connectivity and insulation reliability, and a method for manufacturing the semiconductor device. Another object of the present invention is to provide a film-like adhesive for semiconductors, which makes it possible to provide such a semiconductor device.

One aspect of the present invention includes a first layer made of a first thermosetting adhesive containing a flux compound and a second layer made of a second thermosetting adhesive provided on the first layer. And a film-like adhesive for semiconductors, which satisfies the following condition (A).
Condition (A): The film adhesive for semiconductors is heated at 240 ° C. for 60 minutes in an air atmosphere to obtain a cured product, and the cured product is pulverized into a pulverized product, and the pulverized product is passed through a Tyler sieve 200 mesh and sieved. 1 g of the granules that have passed through and 40 g of ion-exchanged water are mixed to form a mixture, and the mixture is boiled in a closed container under 2 atm at 121 ° C. for 48 hours, and the granules are removed from the mixture after boiling to obtain a mixture. When the chlorine ion concentration of the extracted water is measured by an ion chromatography method, the chlorine ion concentration of the extracted water is 2 mass ppm or less.
According to this film-like adhesive for semiconductors, a semiconductor device having excellent connectivity and insulation reliability can be obtained.

  The ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is preferably 1/4 or more and 3/4 or less. In this case, the connectivity and the insulation reliability can be better balanced.

  The flux compound preferably has a carboxyl group, and more preferably has two or more carboxyl groups. In this case, more excellent connectivity and insulation reliability are likely to be obtained.

［式（２）中、Ｒ^１及びＲ^２は、それぞれ独立して、水素原子又は電子供与性基を示し、ｎは０又は１以上の整数を示す。］ The flux compound is preferably a compound represented by the following formula (2). In this case, more excellent connectivity and insulation reliability are likely to be obtained.

[In the formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron-donating group, and n represents 0 or an integer of 1 or more. ]

  The melting point of the flux compound is preferably 150 ° C. or lower. In this case, the flux is melted before the adhesive is hardened during thermocompression bonding, and the oxide film of solder or the like is reduced and removed, so that more excellent connection reliability is likely to be obtained.

  Another aspect of the present invention is a semiconductor device in which the respective connection portions of the semiconductor chip and the printed circuit board are electrically connected to each other, or the respective connection portions of a plurality of semiconductor chips are electrically connected to each other. The present invention relates to a method for manufacturing a semiconductor device, which includes a step of sealing at least a part of a connection portion with the above-described film adhesive for semiconductors. According to this manufacturing method, a semiconductor device having excellent connectivity and insulation reliability can be obtained.

  Another aspect of the present invention is a semiconductor device in which the respective connection portions of the semiconductor chip and the printed circuit board are electrically connected to each other, or the respective connection portions of a plurality of semiconductor chips are electrically connected to each other. The present invention relates to a semiconductor device, in which at least a part of a connection portion is sealed with a cured product of the above film adhesive for semiconductors. This semiconductor device has excellent connectivity and insulation reliability.

  According to the present invention, it is possible to provide a semiconductor device having excellent connectivity and insulation reliability, and a method for manufacturing the semiconductor device. Further, according to the present invention, it is possible to provide a film-like adhesive for semiconductors which enables the provision of such a semiconductor device.

FIG. 1 is a schematic cross-sectional view showing an embodiment of the film adhesive for semiconductors of the present invention. FIG. 2 is a schematic cross-sectional view showing an embodiment of the semiconductor device of the present invention. FIG. 3 is a schematic cross-sectional view showing another embodiment of the semiconductor device of the present invention. FIG. 4 is a schematic cross-sectional view showing another embodiment of the semiconductor device of the present invention. FIG. 5 is a process sectional view schematically showing an embodiment of the method for manufacturing a semiconductor device of the present invention.

  Hereinafter, modes for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In addition, in this specification, "(meth) acryl" means "acryl" and its corresponding "methacryl." The same applies to expressions such as “(meth) acryloyl”.

<Film-shaped adhesive for semiconductors>
FIG. 1 is a schematic cross-sectional view showing the film adhesive for semiconductors of the present embodiment. The film-like adhesive for semiconductors 1 of the present embodiment comprises a first layer 2 made of a first thermosetting adhesive containing a flux compound (hereinafter, also simply referred to as “first adhesive”), A second layer 3 provided on the first layer 2 and made of a second thermosetting adhesive (hereinafter, also simply referred to as “second adhesive”).

Further, the film adhesive 1 for a semiconductor of the present embodiment satisfies the following condition (A).
Condition (A): The film adhesive for semiconductors is heated at 240 ° C. for 60 minutes in an air atmosphere to obtain a cured product, and the cured product is pulverized into a pulverized product, and the pulverized product is passed through a Tyler sieve 200 mesh and sieved. 1 g of the granules that have passed through and 40 g of ion-exchanged water are mixed to form a mixture, and the mixture is boiled in a closed container under 2 atm at 121 ° C. for 48 hours, and the granules are removed from the mixture after boiling to obtain a mixture. When the chlorine ion concentration of the extracted water is measured by an ion chromatography method, the chlorine ion concentration of the extracted water is 2 mass ppm or less.

  According to the method specified by the above condition (A), chlorine ions in the cured product of the film adhesive for semiconductor 1 can be sufficiently extracted, and if it is a granular product that has passed through the Tyler sieve 200 mesh, The particle size is not particularly limited, but it is preferable to use a granular material that does not pass through a Tyler sieve 5 mesh.

  The film adhesive 1 for a semiconductor according to the present embodiment has an excellent flux activity (the oxide film on the metal surface is sufficiently reduced and removed so that the metal is It has the ability to be easily melted, to prevent the molten metal from spreading wet, and to achieve a state where a metal joint is formed). Therefore, according to the film adhesive 1 for a semiconductor of the present embodiment, excellent connectivity can be obtained. Further, since the film adhesive for semiconductor of the present embodiment satisfies the above condition (A), the film adhesive for semiconductor 1 of the present embodiment suppresses migration, corrosion, etc. due to chlorine ions. It is possible to obtain excellent insulation reliability.

  The chlorine ion concentration of the extracted water is preferably 1.8 mass ppm or less, more preferably 1.6 mass ppm or less, and further preferably 1.4 mass ppm from the viewpoint of obtaining more excellent insulating properties. It is below. The chlorine ion concentration of the extraction water may be 0 mass ppm.

  The chlorine ion concentration of the extraction water is, for example, the type and content of materials (for example, thermosetting component and polymer component) used for the first layer 2 and the second layer 3, the thickness of the first layer 2, and the like. By adjusting the thickness of the second layer 3 and the like, the above range can be obtained. Usually, the material constituting the thermosetting adhesive contains chlorine ions mixed in during the manufacturing process and the like, so that the chlorine ion concentration can be adjusted by appropriately selecting the type of material used. Further, even if the same material is used, the content of chlorine ions varies depending on the manufacturing method (for example, the presence or absence of a chlorine ion removing step). Therefore, when using a commercially available material, it is important to select a commercially available product having a low chlorine ion content. Further, although it has been clarified as a result of the study by the present inventors, in a single-layer film adhesive containing a flux compound, due to a thermosetting resin or the like used in combination with the flux compound, The chloride ion concentration after curing tends to be high. Therefore, as means for adjusting the chlorine ion concentration within the above range, thin the first layer 2 and select a material having a low chlorine ion content as the material used for the second layer 3. Is especially effective.

(First layer)
The first layer is a layer made of the first adhesive. The first adhesive contains a thermosetting component and a flux compound.

[Thermosetting component]
Examples of the thermosetting component include a thermosetting resin and a curing agent.

  The thermosetting resin is not particularly limited, but examples thereof include an epoxy resin, a phenol resin (excluding the case where it is contained as a curing agent), a polyimide resin, a bismaleimide resin, and the like. Among these, the thermosetting resin is preferably an epoxy resin from the viewpoint of being able to easily obtain better connectivity. Epoxy resin tends to contain a large amount of chlorine ions due to the use of epichlorohydrin in its manufacturing process, but in the present embodiment, the content of chlorine ions is reduced in the film adhesive for semiconductors as a whole. Then, the chlorine ion concentration of the extracted water is set to 2 mass ppm or less. Therefore, in this embodiment, excellent insulation reliability can be obtained even when an epoxy resin is used. That is, in the present embodiment, by using the epoxy resin as the thermosetting resin, it is possible to achieve both excellent connectivity and excellent insulation reliability.

  The epoxy resin may be used without particular limitation as long as it has two or more epoxy groups in the molecule. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthalene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin. Epoxy resins, dicyclopentadiene type epoxy resins and various polyfunctional epoxy resins can be used. These can be used alone or as a mixture of two or more kinds.

  The epoxy resin is an epoxy resin having a thermal weight loss rate of 5% or less at 250 ° C. when the temperature at the time of connection is 250 ° C., from the viewpoint of suppressing decomposition of volatile components during connection at high temperature. When the temperature at the time of connection is 300 ° C., it is preferable to use an epoxy resin having a thermal weight loss rate at 300 ° C. of 5% or less.

  The weight average molecular weight of the thermosetting resin (eg, epoxy resin) is less than 10,000, for example. The weight average molecular weight of the thermosetting resin (for example, epoxy resin) is, for example, 150 or more, and may be 500 or more or 1000 or more.

In addition, in this specification, a weight average molecular weight means the weight average molecular weight measured by polystyrene conversion using a high performance liquid chromatography (Shimadzu Corporation make, brand name: C-R4A). The following conditions can be used for the measurement, for example.
Detector: LV4000 UV Detector (Hitachi, Ltd., trade name)
Pump: L6000 Pump (Hitachi, Ltd., trade name)
Column: Gelpack GL-S300MDT-5 (2 in total) (Hitachi Chemical Co., Ltd., trade name)
Eluent: THF / DMF = 1/1 (volume ratio) + LiBr (0.03 mol / L) + H3PO4 (0.06 mol / L)
Flow rate: 1 mL / min

  The content of the thermosetting resin is, for example, 5% by mass or more, preferably 10% by mass or more, and more preferably 15% by mass or more, based on the total mass of the first adhesive. The content of the thermosetting resin is, for example, 75% by mass or less, preferably 50% by mass or less, and more preferably 35% by mass or less, based on the total mass of the first adhesive. When the thermosetting resin contains an epoxy resin, the content of the epoxy resin is preferably within the above range.

  The curing agent can be appropriately selected depending on the thermosetting resin used. For example, when an epoxy resin is used as the thermosetting resin, a phenol resin-based curing agent, an acid anhydride-based curing agent, an amine-based curing agent, an imidazole-based curing agent, a phosphine-based curing agent, etc. may be used as the curing agent. it can. Phenolic resin-based curing agents, acid anhydride-based curing agents, amine-based curing agents, and imidazole-based curing agents exhibit flux activity, so using these curing agents as curing agents further improves connectivity and insulation reliability. be able to. Hereinafter, each curing agent will be described.

(I) Phenolic resin-based curing agent The phenolic resin-based curing agent is not particularly limited as long as it has two or more phenolic hydroxyl groups in the molecule, and examples thereof include phenol novolac resin, cresol novolac resin, and phenol aralkyl resin. , Cresol naphthol formaldehyde polycondensate, triphenylmethane type polyfunctional phenol resin and various polyfunctional phenol resins can be used. These can be used alone or as a mixture of two or more kinds.

  The equivalent ratio of the phenolic resin-based curing agent to the epoxy resin (the number of moles of the phenolic hydroxyl group of the phenolic resin-based curing agent / the number of moles of the epoxy group of the epoxy resin) is good curability, adhesiveness and storage stability. From the viewpoint, 0.3 to 1.5 is preferable, 0.4 to 1.0 is more preferable, and 0.5 to 1.0 is further preferable. When the equivalent ratio is 0.3 or more, the curability and the adhesive strength tend to be improved, and when it is 1.5 or less, the unreacted phenolic hydroxyl group does not remain excessively and the water absorption is It tends to be kept low and the insulation reliability tends to be improved.

(Ii) Acid Anhydride Curing Agent Examples of the acid anhydride curing agent include methylcyclohexanetetracarboxylic dianhydride, trimellitic anhydride, pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, and ethylene glycol bis. Anhydrotrimellitate can be used. These can be used alone or as a mixture of two or more kinds.

  The equivalent ratio of the acid anhydride-based curing agent to the epoxy resin (the number of moles of the acid anhydride group of the acid anhydride-based curing agent / the number of moles of the epoxy group of the epoxy resin) is good curability, adhesiveness and storage. From the viewpoint of stability, 0.3 to 1.5 is preferable, 0.4 to 1.0 is more preferable, and 0.5 to 1.0 is further preferable. If the equivalent ratio is 0.3 or more, the curability and the adhesive strength tend to be improved, and if it is 1.5 or less, the unreacted acid anhydride does not remain excessively and the water absorption is It tends to be kept low and the insulation reliability tends to be improved.

(Iii) Amine-Based Curing Agent As the amine-based curing agent, for example, dicyandiamide can be used.

  The equivalent ratio of the amine-based curing agent to the epoxy resin (the number of active hydrogen groups of the amine-based curing agent / the number of moles of the epoxy groups of the epoxy resin) is from the viewpoint of good curability, adhesiveness and storage stability. 0.3-1.5 are preferable, 0.4-1.0 are more preferable, 0.5-1.0 are still more preferable. When the equivalent ratio is 0.3 or more, the curability and the adhesive strength tend to be improved, and when it is 1.5 or less, unreacted amine does not remain excessively and the insulation reliability is improved. Tend to do.

(Iv) Imidazole-based curing agent Examples of the imidazole-based curing agent include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1- Cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6 -[2'-Methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl- (1')]-ethyl-s-triazine, 2, 4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s Triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-. Examples thereof include dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and adducts of epoxy resin and imidazoles. Among these, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecyl, from the viewpoint of excellent curability, storage stability, connectivity and insulation reliability. Imidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino -6- [2'-Ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl- s-Triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2- Phenyl-4-methyl-5-hydroxymethylimidazole is preferred. These can be used alone or in combination of two or more. Further, these may be microencapsulated latent curing agents.

  The content of the imidazole-based curing agent is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the epoxy resin. When the content of the imidazole-based curing agent is 0.1 part by mass or more, the curability tends to be improved. When the content of the imidazole-based curing agent is 20 parts by mass or less, the fluidity of the first adhesive at the time of pressure bonding can be ensured, and the first adhesive between the connecting portions can be sufficiently removed. be able to. As a result, the first adhesive is suppressed from being hardened in the state where it intervenes between the solder and the connection portion, so that poor connection is less likely to occur.

(V) Phosphine-based curing agent Examples of the phosphine-based curing agent include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra (4-methylphenyl) borate and tetraphenylphosphonium (4-fluorophenyl) borate. Be raised.

  The content of the phosphine-based curing agent is preferably 0.1 to 10 parts by mass and more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the epoxy resin. When the content of the phosphine-based curing agent is 0.1 part by mass or more, the curability tends to be improved, and when it is 10 parts by mass or less, the first adhesive is cured before the metal bond is formed. There is no problem, and poor connection is less likely to occur.

  The phenol resin-based curing agent, the acid anhydride-based curing agent, and the amine-based curing agent may be used each alone or as a mixture of two or more. The imidazole-based curing agent and the phosphine-based curing agent may be used alone, or may be used together with a phenol resin-based curing agent, an acid anhydride-based curing agent or an amine-based curing agent.

[Flux compound]
The flux compound is a compound having a flux activity, and functions as a flux agent in the first adhesive. As the flux compound, any known flux compound can be used without particular limitation as long as it reduces and removes an oxide film on the surface of solder or the like to facilitate metal bonding. As the flux compound, one kind may be used alone, or two or more kinds may be used in combination. However, the flux compound does not include the above-mentioned curing agent.

  The flux compound preferably has a carboxyl group, and more preferably has two or more carboxyl groups, from the viewpoints that sufficient flux activity is obtained and more excellent connectivity and insulation reliability are obtained. Among these, compounds having two carboxyl groups are preferable. The compound having two carboxyl groups is less likely to volatilize even at a high temperature at the time of connection as compared with the compound having one carboxyl group (monocarboxylic acid), and the generation of voids can be further suppressed. Further, when a compound having two carboxyl groups is used, the increase in the viscosity of the film adhesive for semiconductors during storage and connection work is further suppressed, as compared with the case where a compound having three or more carboxyl groups is used. Therefore, the connectivity and insulation reliability of the semiconductor device can be further improved.

As the flux compound having a carboxyl group, a compound having a group represented by the following formula (1) is preferably used.

In formula (1), R ¹ represents a hydrogen atom or an electron donating group.

From the viewpoint of excellent reflow resistance and further excellent connectivity and insulation reliability, R ¹ is preferably an electron donating group. In the present embodiment, the first adhesive contains an epoxy resin and a curing agent, and further includes a compound having a group represented by the formula (1), wherein R ¹ is an electron donating group. By including it, even when it is applied as a film adhesive for semiconductors in a flip chip connection method of metal bonding, it is possible to manufacture a semiconductor device which is excellent in reflow resistance, connectivity and insulation reliability.

  In order to improve the reflow resistance, it is necessary to suppress the decrease in adhesive strength after moisture absorption at high temperature. Conventionally, a carboxylic acid has been used as a flux compound, but the present inventors believe that the conventional flux compound causes a decrease in adhesive force for the following reasons.

  Usually, the epoxy resin and the curing agent react to advance the curing reaction, but at this time, the carboxylic acid that is a flux compound is taken into the curing reaction. That is, an ester bond may be formed by the reaction between the epoxy group of the epoxy resin and the carboxyl group of the flux compound. This ester bond is liable to cause hydrolysis due to moisture absorption and the like, and it is considered that the decomposition of the ester bond is one of the causes of the decrease in adhesive strength after moisture absorption.

On the other hand, among the compounds having a group represented by the formula (1), a compound having a group in which R ¹ is an electron donating group, that is, a compound having a carboxyl group having an electron donating group in the vicinity thereof. In the case of containing a carboxyl group, sufficient flux activity is obtained, and even when the above-mentioned ester bond is formed, the electron density of the ester bond portion is increased by the electron-donating group and decomposition of the ester bond is suppressed. To be done. Further, since a substituent (electron-donating group) is present in the vicinity of the carboxyl group, it is considered that the reaction between the carboxyl group and the epoxy resin is suppressed due to steric hindrance, and the ester bond is difficult to form.

For these reasons, when the first adhesive which further contains the compound having the group represented by the formula (1) and R ¹ is an electron-donating group is used, a composition change due to moisture absorption occurs. Difficult and excellent adhesion is maintained. Further, the above-mentioned action can also be said that the curing reaction between the epoxy resin and the curing agent is not easily inhibited by the flux compound, and by this action, the connectivity and the connectivity due to the sufficient progress of the curing reaction between the epoxy resin and the curing agent. The effect of improving insulation reliability can also be expected.

  When the electron-donating group has a stronger electron-donating property, the above-described effect of suppressing the decomposition of the ester bond tends to be easily obtained. Further, when the steric hindrance of the electron-donating group is large, the effect of suppressing the above-mentioned reaction between the carboxyl group and the epoxy resin can be easily obtained. The electron-donating group preferably has a well-balanced electron-donating property and steric hindrance.

  Examples of the electron donating group include an alkyl group, a hydroxyl group, an amino group, an alkoxy group and an alkylamino group. The electron-donating group is preferably a group that is difficult to react with other components (for example, epoxy resin), specifically, an alkyl group, a hydroxyl group or an alkoxy group is preferable, and an alkyl group is more preferable.

  As the alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable. As the carbon number of the alkyl group increases, the electron donating property and the steric hindrance tend to increase. An alkyl group having a carbon number in the above range is excellent in the balance of electron donating property and steric hindrance, and therefore, the alkyl group further remarkably improves connectivity and insulation reliability.

  The alkyl group may be linear or branched, and is preferably linear. When the alkyl group is linear, the carbon number of the alkyl group is preferably not more than the carbon number of the main chain of the flux compound from the viewpoint of the balance between electron donating property and steric hindrance. For example, when the flux compound is a compound represented by the following formula (2) and the electron donating group is a linear alkyl group, the carbon number of the alkyl group is the carbon number of the main chain of the flux compound ( It is preferably n + 1) or less.

  As the alkoxy group, an alkoxy group having 1 to 10 carbon atoms is preferable, and an alkoxy group having 1 to 5 carbon atoms is more preferable. As the carbon number of the alkoxy group increases, the electron donating property and the steric hindrance tend to increase. An alkoxy group having a carbon number in the above range has an excellent balance of electron donating property and steric hindrance, and therefore, the alkoxy group further remarkably improves connectivity and insulation reliability.

  The alkyl group portion of the alkoxy group may be linear or branched, and is preferably linear. When the alkoxy group is linear, the number of carbon atoms of the alkoxy group is preferably equal to or less than the number of carbon atoms of the main chain of the flux compound from the viewpoint of the balance between electron donating property and steric hindrance. For example, when the flux compound is a compound represented by the following formula (2) and the electron-donating group is a linear alkoxy group, the carbon number of the alkoxy group is the carbon number of the main chain of the flux compound ( It is preferably n + 1) or less.

  Examples of the alkylamino group include a monoalkylamino group and a dialkylamino group. As the monoalkylamino group, a monoalkylamino group having 1 to 10 carbon atoms is preferable, and a monoalkylamino group having 1 to 5 carbon atoms is more preferable. The alkyl group portion of the monoalkylamino group may be linear or branched, and is preferably linear.

  As the dialkylamino group, a dialkylamino group having 2 to 20 carbon atoms is preferable, and a dialkylamino group having 2 to 10 carbon atoms is more preferable. The alkyl group portion of the dialkylamino group may be linear or branched, and is preferably linear.

  As the flux compound having two carboxyl groups, the compound represented by the following formula (2) can be preferably used. The compound represented by the following formula (2) can further improve the reflow resistance, connectivity and insulation reliability of the semiconductor device.

In formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron donating group, and n represents 0 or an integer of 1 or more. Plural R ^{2 s} may be the same or different from each other.

R ¹ has the same meaning as ^{R 1} in Formula (1). Further, the electron donating property represented by R ² is the same as the above-mentioned examples of the electron donating group described as R ¹ . For the same reason as explained in the formula (1), R ¹ in the formula (2) is preferably an electron donating group.

  N in the formula (2) is preferably 1 or more. When n is 1 or more, as compared with the case where n is 0, the flux compound is less likely to volatilize even at a high temperature at the time of connection, and the generation of voids can be further suppressed. Further, n in the formula (2) is preferably 15 or less, more preferably 11 or less, and may be 6 or less or 4 or less. When n is 15 or less, more excellent connectivity and insulation reliability can be obtained.

  Further, as the flux compound, a compound represented by the following formula (3) is more suitable. According to the compound represented by the following formula (3), the reflow resistance, connectivity and insulation reliability of the semiconductor device can be further improved.

In formula (3), R ¹ and R ² each independently represent a hydrogen atom or an electron donating group, and m represents 0 or an integer of 1 or more.

  M in formula (3) is preferably 10 or less, more preferably 5 or less, and further preferably 3 or less. When m is 10 or less, more excellent connectivity and insulation reliability can be obtained.

In formula (3), R ¹ and R ² may be hydrogen atoms or electron donating groups. At least one of R ¹ and R ² is preferably an electron-donating group from the viewpoint of obtaining more excellent connectivity and insulation reliability. When R ¹ is an electron-donating group and R ² is a hydrogen atom, the melting point tends to be low, and the connectivity and insulation reliability of the semiconductor device may be improved in some cases. Further, when R ¹ and R ² are different electron donating groups, the melting point tends to be lower than in the case where R ¹ and R ² are the same electron donating group, so that the semiconductor device is connected. In some cases, the reliability and insulation reliability can be further improved.

In the formula (3), when R ¹ and R ² are the same electron-donating group, the structure tends to be symmetrical and the melting point tends to be high, but even in this case, the effect of the present invention can be sufficiently obtained. In particular, when the melting point is sufficiently low as 150 ° C. or lower, even if R ¹ and R ² are the same group, the connectivity and insulation reliability are about the same as when R ¹ and R ² are different groups. Is obtained.

  Examples of the flux compound include dicarboxylic acids selected from succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid, and dicarboxylic acids thereof. A compound having an electron-donating group at the position (2-methylglutaric acid, etc.) and a compound having an electron-donating group at the 3-position of these dicarboxylic acids (3-methylglutaric acid, etc.) can be used.

  The melting point of the flux compound is preferably 150 ° C or lower, more preferably 140 ° C or lower, further preferably 130 ° C or lower, and particularly preferably 100 ° C or lower. Such a flux compound is likely to exhibit sufficient flux activity before the curing reaction between the epoxy resin and the curing agent occurs. Therefore, according to the film-like adhesive for semiconductors using the first adhesive containing such a flux compound, it is possible to realize a semiconductor device having more excellent connectivity and insulation reliability. The melting point of the flux compound is preferably 25 ° C or higher, more preferably 50 ° C or higher. The flux compound is preferably solid at room temperature (25 ° C).

  The melting point of the flux compound can be measured using a general melting point measuring device. The sample whose melting point is to be measured is pulverized into fine powder and it is required to reduce the temperature deviation in the sample by using a trace amount. As a sample container, a capillary tube with one end closed is often used, but depending on the measuring device, there is also one that is sandwiched between two microscope cover glasses to form a container. Further, when the temperature is rapidly raised, a temperature gradient is generated between the sample and the thermometer, which causes a measurement error. Therefore, the heating at the time of measuring the melting point can be measured at an increase rate of 1 ° C. or less per minute. desirable.

  Since the sample whose melting point is to be measured is prepared as a fine powder as described above, the sample before melting is opaque due to diffuse reflection on the surface. It is usual to set the temperature at which the appearance of the sample begins to become transparent as the lower limit point of the melting point and the temperature at which the sample has completely melted as the upper limit point. There are various types of measuring devices, but the most classical device is a device in which a capillary tube filled with a sample is attached to a double-tube thermometer and heating is performed in a warm bath. A highly viscous liquid is used as the liquid for the hot bath for the purpose of attaching a capillary tube to the double-tube thermometer, and concentrated sulfuric acid or silicone oil is often used, so that the sample comes near the reservoir at the tip of the thermometer. Install. Further, as the melting point measuring device, it is possible to use a device that heats using a metal heat block and automatically determines the melting point while adjusting the heating while measuring the light transmittance.

  In the present specification, the melting point of 150 ° C. or lower means that the upper limit of the melting point is 150 ° C. or lower, and the melting point of 25 ° C. or higher means that the lower limit of the melting point is 25 ° C. or higher. means.

  The content of the flux compound is, based on the total mass of the first adhesive, preferably 0.5 mass% or more. The content of the flux compound is preferably 10% by mass or less, and more preferably 5% by mass or less, based on the total mass of the first adhesive.

[Polymer component]
The first adhesive may contain a polymer component, if necessary. The first adhesive containing a polymer component is more excellent in heat resistance and film formability. The polymer component may be referred to as a film forming agent.

  Examples of the polymer component include phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate ester resin, acrylic resin, polyester resin, polyethylene resin, polyether sulfone resin, polyetherimide resin, polyvinyl acetal resin, urethane resin. And acrylic rubber. Among these, phenoxy resin, polyimide resin, urethane resin, acrylic resin, acrylic rubber, cyanate ester resin and polycarbodiimide resin are preferable from the viewpoint of excellent heat resistance and film forming property, and phenoxy resin, polyimide resin and acrylic resin are more preferable. Further, phenoxy resin is more preferable. These polymer components can be used alone or as a mixture or copolymer of two or more kinds. However, the polymer component does not include the above-mentioned epoxy resin which is a thermosetting resin and a compound corresponding to a filler described later.

  The weight average molecular weight of the polymer component is, for example, 10,000 or more, preferably 20,000 or more, and more preferably 30,000 or more. With such a polymer component, the heat resistance and the film forming property of the first adhesive can be further improved. The weight average molecular weight of the polymer component is preferably 200,000 or less, more preferably 100,000 or less. With such a polymer component, the heat resistance of the first adhesive can be further improved. From these viewpoints, the weight average molecular weight of the polymer component may be 10,000 to 200,000, 20,000 to 100,000 or 30,000 to 100,000.

  When the first adhesive contains a polymer component, the ratio (mass ratio) of the content of the thermosetting resin to the content of the polymer component is preferably 0.01 to 5, It is more preferably -3, and even more preferably 0.1-2. By setting the above ratio to 0.01 or more, better curability and adhesive strength can be obtained, and by setting the above ratio to 5 or less, better film formability can be obtained. When the thermosetting resin contains an epoxy resin, the ratio (mass ratio) of the content of the epoxy resin to the content of the polymer component is preferably within the above range.

[Filler]
The first adhesive may contain a filler, if necessary. The filler can control the viscosity of the first adhesive, the physical properties of the cured product of the first adhesive, and the like. Specifically, with the filler, for example, it is possible to suppress the occurrence of voids during connection, reduce the moisture absorption rate of the cured product of the first adhesive, and the like.

  Examples of the filler include inorganic fillers (inorganic particles) and organic fillers (organic particles). Examples of the inorganic filler include glass, silica, alumina, titanium oxide, mica, insulating inorganic fillers such as boron nitride, and among them, at least one selected from the group consisting of silica, alumina, titanium oxide and boron nitride. At least one selected from the group consisting of silica, alumina and boron nitride is more preferable. The insulating inorganic filler may be whiskers. Examples of the whiskers include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, boron nitride and the like. Examples of the organic filler include resin fillers (resin particles). Examples of the resin filler include polyurethane and polyimide. Compared with inorganic fillers, resin fillers can impart flexibility at high temperatures such as 260 ° C., and thus are suitable for improving reflow resistance and, at the same time, can impart flexibility, thereby improving film formability. effective.

  The content of the inorganic filler is such that it is easy to adjust the elastic modulus to a desired range, and while suppressing warpage, the occurrence of voids can be more sufficiently reduced, and further excellent connectivity and insulation reliability. From the viewpoint of obtaining the property, it may be 50% by mass or more, 70% by mass or more, or 80% by mass or more based on the total mass of the filler. The content of the inorganic filler may be 100% by mass or less or 90% by mass or less.

  From the viewpoint of further excellent insulation reliability, the filler is preferably insulative (is an insulative filler). It is preferable that the first adhesive does not contain a conductive metal filler (metal particles) such as a silver filler or a solder filler, and a conductive inorganic filler such as carbon black.

  The content of the insulative filler is such that it is easy to adjust the elastic modulus to a desired range, and while suppressing warpage, the occurrence of voids can be more sufficiently reduced, and further excellent connectivity and insulation From the viewpoint of obtaining reliability, it may be 50% by mass or more, 70% by mass or more, or 90% by mass or more based on the total mass of the filler. The filler may consist essentially of insulating filler. That is, the filler may be substantially free of conductive filler. "Substantially free" means that the content of the conductive filler in the filler is less than 0.5% by mass based on the total mass of the filler.

  The physical properties of the filler may be appropriately adjusted by surface treatment. From the viewpoint of improving dispersibility or adhesive strength, the filler is preferably a surface-treated filler. Examples of the surface treatment agent include glycidyl (epoxy), amine, phenyl, phenylamino, (meth) acrylic or vinyl compounds.

  As the surface treatment, a silane treatment with a silane compound such as an epoxysilane-based, aminosilane-based, or acrylsilane-based is preferable in terms of ease of surface treatment. As the surface treatment agent, at least one selected from the group consisting of glycidyl compounds, phenylamino compounds, and (meth) acrylic compounds is preferable from the viewpoint of excellent dispersibility, fluidity and adhesive strength. .. From the viewpoint of excellent storage stability, the surface treatment agent is preferably at least one selected from the group consisting of phenyl compounds and (meth) acrylic compounds.

  The average particle size of the filler is preferably 1.5 μm or less from the viewpoint of preventing biting during flip chip connection, and more preferably 1.0 μm or less from the viewpoint of excellent visibility (transparency).

  The content of the filler is based on the total mass of the first adhesive, from the viewpoint that the heat dissipation is suppressed from being lowered, and from the viewpoint that it is easy to suppress the occurrence of voids, the increase in moisture absorption, and the like, 15 mass% or more is preferable, 20 mass% or more is more preferable, and 40 mass% or more is further preferable. Regarding the content of the filler, it is easy to suppress the flowability of the first adhesive from decreasing due to the increase in viscosity, and the trapping (trapping) of the filler into the connection portion is easily suppressed, so that the connectivity and the insulation reliability are improved. From the viewpoint of easily suppressing the deterioration of the property, 90% by mass or less is preferable, and 80% by mass or less is more preferable, based on the total mass of the first adhesive. From these viewpoints, the content of the filler is preferably 15 to 90% by mass, more preferably 20 to 80% by mass, and further preferably 40 to 80% by mass, based on the total mass of the first adhesive.

[Additive]
The first adhesive may further contain additives such as an antioxidant, a coupling agent (silane coupling agent, titanium coupling agent, etc.), a leveling agent, an ion trap agent, etc., if necessary. These may be used alone or in combination of two or more. Among these, a silane coupling agent is preferably used. As the silane coupling agent, for example, a glycidyl group-containing silane coupling agent is preferably used. The blending amounts of these additives may be appropriately adjusted so that the effects of each additive are exhibited. For example, the content of the silane coupling agent may be 0.1% by mass or more or 0.5% by mass or more, and 5% by mass or less or 3% by mass or less, based on the total mass of the first adhesive. May be

(Second layer)
The second layer is a layer made of a second adhesive. The second adhesive contains a thermosetting component.

[Thermosetting component]
Examples of thermosetting components include radically polymerizable compounds and thermal radical generators. In the present embodiment, the first adhesive may include a thermosetting resin and a curing agent as the thermosetting components, and the second adhesive may include a radical polymerizable compound and a thermal radical generator as the thermosetting components. preferable. In this case, even when the pressure bonding is performed at a high temperature for a short time, the second layer is cured more quickly and sufficiently than the first layer, so that the occurrence of voids and the scattering of solder are less likely to occur. , More excellent connectivity and insulation reliability can be obtained. Further, since the crimping time can be shortened, the productivity can be improved, and further, the flip chip package can be easily made highly functional and highly integrated. Moreover, since it becomes easy to make the amount of chlorine ions in the second adhesive and its cured product smaller than the amount of chlorine ions in the first adhesive and its cured product, the chlorine ion concentration in the above-mentioned extracted water can be reduced. Is easy to reduce.

  The second layer may contain a thermosetting resin such as an epoxy resin as a thermosetting component, but the second layer is thermosetting from the viewpoint of reducing the above chlorine ion concentration and the rapid curability. It is preferable that the resin (especially epoxy resin) is not substantially contained. Here, "substantially free from" means that the content of the thermosetting resin (for example, epoxy resin) in the second adhesive is less than 0.5% by mass based on the total mass of the second adhesive. Means that.

  The radical-polymerizable compound is a compound capable of radical polymerization reaction with the generation of radicals due to heat, light, radiation, electrochemical action and the like. Examples of the radically polymerizable compound include (meth) acrylic compounds and vinyl compounds. As the radically polymerizable compound, a (meth) acrylic compound is preferable from the viewpoint of excellent durability, electric insulation and heat resistance. The (meth) acrylic compound is not particularly limited as long as it is a compound having one or more (meth) acryloyl groups in the molecule, and examples thereof include bisphenol A type, bisphenol F type, naphthalene type, phenol novolac type, and cresol novolac type. , (Meth) acrylic compounds containing a skeleton of phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, fluorene type, adamantane type or isocyanuric acid type; various polyfunctional (meth) acrylic compounds (Excluding (meth) acrylic compound) contained therein can be used. Examples of polyfunctional (meth) acrylic compounds include pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and trimethylolpropane di (meth) acrylate. The radically polymerizable compound may be used alone or in combination of two or more.

  The radically polymerizable compound is a bisphenol A type skeleton, a bisphenol F type skeleton, a naphthalene type skeleton, from the viewpoint of obtaining more excellent connectivity and insulation reliability, as well as from the viewpoint of being excellent in heat resistance and suppressing generation of voids. , Fluorene type skeleton, adamantane type skeleton or isocyanuric acid type skeleton, and more preferably fluorene type skeleton or bisphenol A type skeleton. From the viewpoint that the generation of voids can be further suppressed, the radically polymerizable compound is more preferably a (meth) acrylate having any of the skeletons described above.

  The radically polymerizable compound is preferably solid at room temperature (25 ° C.). Voids are less likely to occur in the solid form as compared with the liquid form, and the viscosity (tack) of the second adhesive before curing (B stage) is small and the handleability is excellent. Examples of the radically polymerizable compound that is solid at room temperature (25 ° C.) include (meth) acrylates having a bisphenol A type skeleton, a fluorene type skeleton, an adamantane type skeleton, or an isocyanuric acid type skeleton.

  The number of functional groups of the (meth) acryloyl group in the radically polymerizable compound is preferably 3 or less. When the number of functional groups is large, the curing network may proceed rapidly and unreacted groups may remain. On the other hand, when the number of functional groups is 3 or less, the number of functional groups does not increase too much, and curing in a short time is likely to proceed sufficiently, so that it is easy to prevent the curing reaction rate from decreasing.

  The molecular weight of the radically polymerizable compound is preferably less than 2000, more preferably 1000 or less. The smaller the molecular weight of the radically polymerizable compound, the easier the reaction proceeds, and the higher the curing reaction rate.

  The content of the radically polymerizable compound is 10% by mass or more based on the total mass of the second adhesive from the viewpoint that the curable component is prevented from becoming small and the flow of the resin after curing is easily controlled. Is preferable, and 15 mass% or more is more preferable. The content of the radically polymerizable compound is 50% by mass or less based on the total mass of the second adhesive from the viewpoint that the cured product is suppressed from becoming too hard and the warp of the package is easily suppressed from increasing. Is preferable, and 40 mass% or less is more preferable. From these viewpoints, the content of the radically polymerizable compound is preferably 10 to 50% by mass, and more preferably 15 to 40% by mass, based on the total mass of the second adhesive.

  The thermal radical generator can be used without particular limitation as long as it functions as a curing agent for the radically polymerizable compound. Examples of the heat radical generator include azo compounds and peroxides (organic peroxides, etc.). The heat radical generator is preferably a peroxide, and more preferably an organic peroxide. In this case, the radical reaction does not proceed in the step of drying the solvent when forming the film form, and the handleability and storage stability are excellent. Therefore, when peroxide is used as the heat radical generator, more excellent connectivity and insulation reliability are likely to be obtained. Examples of the organic peroxide include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate and peroxyester. As the organic peroxide, at least one selected from the group consisting of hydroperoxide, dialkyl peroxide and peroxyester is preferable from the viewpoint of excellent storage stability. Further, as the organic peroxide, at least one selected from the group consisting of hydroperoxide and dialkyl peroxide is preferable from the viewpoint of excellent heat resistance. Examples of the dialkyl peroxide include dicumyl peroxide and di-tert-butyl peroxide.

  The content of the thermal radical generator is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, with respect to 100 parts by mass of the radically polymerizable compound, from the viewpoint that curing is easily promoted. The content of the thermal radical generator is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less with respect to 100 parts by mass of the radically polymerizable compound. When the upper limit of the content of the heat radical generator is in the above range, curing is prevented from rapidly progressing and the number of reaction points is suppressed, whereby the molecular chain is shortened, and unreacted groups are Remaining is suppressed. Therefore, when the upper limit of the content of the heat radical generator is within the above range, it is easy to suppress the decrease in reliability. From these viewpoints, the content of the heat radical generator is preferably 0.5 to 10 parts by mass, and more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the radically polymerizable compound.

[Other ingredients]
The second adhesive may further contain the above-described polymer component, filler, and additive that can be used in the first adhesive, if necessary. The preferred embodiments (type, content, etc.) of the polymer component, filler and additive are also the same as in the case of the first adhesive. For example, when the second adhesive contains a polymer component, the ratio (mass ratio) of the content of the radically polymerizable compound to the content of the polymer component is preferably 0.01 to 5. The second adhesive may be blended with a polymerizable compound other than the radically polymerizable compound (for example, a cationically polymerizable compound and an anionically polymerizable compound).

  The second adhesive may contain a flux compound, but preferably contains substantially no flux compound. Here, “not substantially containing” means that the content of the flux compound in the second adhesive is less than 0.5% by mass based on the total mass of the second adhesive.

The second adhesive preferably satisfies the following condition (B).
Condition (B): The second adhesive is heated in an air atmosphere at 240 ° C. for 60 minutes to obtain a cured product, and the cured product is pulverized into a pulverized product, and the pulverized product is passed through a Tyler sieve 200 mesh, Extraction obtained by mixing 1 g of the passed granules with 40 g of ion-exchanged water to form a mixture, boiling the mixture in a sealed container at 121 ° C. for 48 hours under 2 atm, and removing the granules from the mixture after boiling. When the chlorine ion concentration of water is measured by an ion chromatography method, the chlorine ion concentration of the extracted water is 1 mass ppm or less.

  The chlorine ion concentration of the extracted water under the condition (B) is more preferably 0.8 mass ppm or less, further preferably 0.7 mass ppm or less, and may be 0 mass ppm. In the measurement of the chlorine ion concentration of the extracted water shown in the condition (B), the first layer and the second layer may be separated after curing the film adhesive for semiconductors. The first and second layers may be separated before curing.

  The thickness of the first layer 2 and the thickness of the second layer 3 in the film adhesive 1 for a semiconductor are the effect of improving the connectivity due to the flux compound in the first layer, the insulation reliability due to chlorine ions. It can be appropriately set in consideration of the influence on the above.

  Specifically, the ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is preferably 1/4 or more, and 1/3 or more. Is more preferable. When the ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is 1/4 or more, the chloride ion concentration of the extracted water under the above condition (A) is desired. It tends to be adjusted to the range, and more excellent insulation reliability tends to be obtained. Further, the ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is preferably 3/4 or less. When the ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is 3/4 or less, more excellent connectivity tends to be obtained. From these viewpoints, the ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is preferably 1/4 or more and 3/4 or less, and more preferably It is 1/3 or more and 3/4 or less.

  The total thickness of the film adhesive for semiconductors, the thickness of the first layer, and the thickness of the second layer can be adjusted according to the height of the connection portion. The total thickness of the film adhesive for semiconductors may be, for example, 10 to 100 μm, 10 to 80 μm, or 10 to 50 μm. In the present embodiment, the total thickness of the first layer and the second layer may be in the above range. The thickness of the first layer may be, for example, 1 to 50 μm, 3 to 50 μm, 4 to 30 μm, or 5 to 20 μm. The thickness of the second layer may be, for example, 7 to 50 μm, 8 to 45 μm, or 10 to 40 μm.

  The film adhesive for semiconductors of the present embodiment is provided on the surface of the first layer opposite to the second layer and / or on the surface of the second layer opposite to the first layer. , A base film and / or a protective film may be provided. In this case, an adhesive layer may be provided between the base film or protective film and the first layer, and / or between the base film or protective film and the second layer.

  In the film adhesive for semiconductors, the first layer and the second layer may be adjacent to each other. In this case, it is preferable that the first layer and the second layer are formed so as not to be separated from each other. For example, the peel strength between the first layer and the second layer may be 10 N / m or more.

  The film adhesive for semiconductors can be cured by heating to form a cured product of the film adhesive for semiconductors. The curing reaction rate when the film-like adhesive for semiconductors is heated at 240 ° C. for 60 minutes is preferably 90% or more, more preferably 95% or more. In this embodiment, the curing reaction rate when the first adhesive is heated at 240 ° C. for 60 minutes is preferably in the above range, and the curing reaction rate when the second adhesive is heated at 240 ° C. for 60 minutes. Is preferably in the above range. The curing reaction rate can be obtained by measuring the calorific value using DSC (manufactured by Rigaku Corporation, trade name: DSC8231 type).

  The film adhesive for a semiconductor can be suitably used for manufacturing a semiconductor device by electrically connecting a semiconductor chip and a wiring circuit board or connecting portions of the semiconductor chips to each other. The film adhesive for semiconductors may be used so that the flux compound in the first layer functions as a flux agent, that is, so that the first layer and the surface of the above-mentioned connecting portion are in contact with each other. It is not particularly limited.

<Method of manufacturing film adhesive for semiconductor>
As the film adhesive for semiconductors of the present embodiment, for example, a first film adhesive having a first layer and a second film adhesive having a second layer are prepared, and a first film adhesive is prepared. It can be obtained by laminating a first film adhesive having a layer and a second film adhesive having a second layer.

  In the step of preparing the first film adhesive, for example, first, a thermosetting resin, a curing agent and a flux compound, and other components such as a polymer component and a filler that are added as necessary are added to an organic solvent. A resin varnish (coating varnish) is prepared by adding the above ingredients and dissolving or dispersing them by stirring, mixing, and kneading. Then, on the base film or protective film that has been subjected to a release treatment, after coating the resin varnish using a knife coater, roll coater, applicator, etc., reduce the organic solvent by heating, the base film or protective film A first layer of a first adhesive can be formed on top.

  As the organic solvent used for preparing the resin varnish, those having a property capable of uniformly dissolving or dispersing each component are preferable. Examples of the organic solvent include dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, diethylene glycol dimethyl ether, toluene, benzene, xylene, methyl ethyl ketone, tetrahydrofuran, ethyl cellosolve, ethyl cellosolve acetate, butyl cellosolve, dioxane, cyclohexanone, And ethyl acetate. These organic solvents can be used alone or in combination of two or more kinds. Stirring and mixing and kneading at the time of preparing the resin varnish can be performed using, for example, a stirrer, a raker, a three-roll, a ball mill, a bead mill or a homodisper.

  The base film and the protective film are not particularly limited as long as they have heat resistance that can withstand the heating conditions when volatilizing the organic solvent, polypropylene film, polyolefin film such as polymethylpentene film, polyethylene terephthalate film, Examples thereof include polyester films such as polyethylene naphthalate film, polyimide films and polyetherimide films. The base film and the protective film are not limited to a single layer made of these films, and may be a multilayer film made of two or more kinds of materials. Moreover, the above-mentioned base film and protective film may have an adhesive layer on one surface thereof.

  The drying conditions for volatilizing the organic solvent from the resin varnish applied to the base film are preferably conditions under which the organic solvent is sufficiently volatilized, specifically, 50 to 200 ° C. and 0.1 to 90 minutes. Is preferably heated. The organic solvent is preferably removed up to 1.5% by mass or less with respect to the total mass of the first film adhesive, as long as the voids or the viscosity adjustment after mounting are not affected.

  In the step of preparing the second film adhesive, the second layer made of the second adhesive can be formed on the base film or the protective film by the same method as that for the first layer.

  Examples of the method for bonding the first film adhesive and the second film adhesive include methods such as hot pressing, roll lamination, and vacuum lamination. Lamination may be performed, for example, under heating conditions of 30 to 120 ° C.

  The film adhesive for semiconductors of the present embodiment, for example, after forming one of the first layer or the second layer on the substrate film, on the obtained first layer or the second layer, It may be obtained by forming the other of the first layer and the second layer. The first layer and the second layer may be formed by the same method as the method for forming the first layer and the second layer in the above-described production of the film-like adhesive with substrate.

  The film adhesive for semiconductors of the present embodiment may be obtained, for example, by forming the first layer and the second layer substantially simultaneously on the base film. Examples of the method for simultaneously applying and manufacturing the first adhesive and the second adhesive include a coating method such as a sequential coating method or a multilayer coating method.

<Semiconductor device>
The semiconductor device of this embodiment will be described below with reference to FIGS. FIG. 2 is a schematic cross-sectional view showing an embodiment of the semiconductor device of the present invention. As shown in FIG. 2A, the semiconductor device 100 includes a semiconductor chip 10 and a board (wiring circuit board) 20 facing each other, and wirings 15 arranged on the surfaces of the semiconductor chip 10 and the board 20 facing each other. Connection bumps 30 for connecting the semiconductor chip 10 and the wiring 15 of the substrate 20 to each other, and an adhesive (first adhesive and second adhesive) filled in a space between the semiconductor chip 10 and the substrate 20 without any gap. It has the sealing part 40 which consists of hardened | cured material. The semiconductor chip 10 and the substrate 20 are flip-chip connected by the wiring 15 and the connection bumps 30. The wiring 15 and the connection bumps 30 are sealed with a cured product of an adhesive and are shielded from the external environment. The sealing portion 40 has an upper portion 40a containing a cured product of the first adhesive and a lower portion 40b containing a cured product of the second adhesive.

  As shown in FIG. 2B, in the semiconductor device 200, the semiconductor chip 10 and the substrate 20 facing each other, the bumps 32 respectively arranged on the mutually facing surfaces of the semiconductor chip 10 and the substrate 20, the semiconductor chip 10 and the semiconductor chip 10 are provided. The sealing section 40 is made of a cured product of an adhesive (first adhesive and second adhesive) that fills the voids between the substrates 20 with no space. The semiconductor chip 10 and the substrate 20 are flip-chip connected by connecting opposite bumps 32 to each other. The bump 32 is sealed with a cured product of an adhesive and is shielded from the external environment. The sealing portion 40 has an upper portion 40a containing a cured product of the first adhesive and a lower portion 40b containing a cured product of the second adhesive.

  FIG. 3 is a schematic cross-sectional view showing another embodiment of the semiconductor device of the present invention. As shown in FIG. 3A, the semiconductor device 300 is the same as the semiconductor device 100 except that the two semiconductor chips 10 are flip-chip connected by the wiring 15 and the connection bumps 30. As shown in FIG. 3B, the semiconductor device 400 is similar to the semiconductor device 200 except that the two semiconductor chips 10 are flip-chip connected by the bumps 32.

  The semiconductor chip 10 is not particularly limited, and element semiconductors composed of the same type of element such as silicon and germanium, and compound semiconductors such as gallium arsenide and indium phosphide can be used.

  The substrate 20 is not particularly limited as long as it is a circuit board, and an unnecessary portion of a metal film is etched on the surface of an insulating substrate whose main component is glass epoxy, polyimide, polyester, ceramic, epoxy, bismaleimide triazine, or the like. Circuit board having wiring (wiring pattern) 15 formed by removal, circuit board having wiring 15 formed by metal plating or the like on the surface of the insulating substrate, and wiring by printing a conductive substance on the surface of the insulating substrate A circuit board on which 15 is formed can be used.

  The connection parts such as the wiring 15 and the bumps 32 are mainly composed of gold, silver, copper, and solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc.). ), Nickel, tin, lead, etc., and may contain a plurality of metals.

  Among the above metals, gold, silver, and copper are preferable, and silver and copper are more preferable, from the viewpoint of forming a package having excellent electrical conductivity and thermal conductivity of the connection portion. From the viewpoint of a package with reduced cost, silver, copper, and solder, which are inexpensive materials, are preferable, copper and solder are more preferable, and solder is still more preferable. When an oxide film is formed on the surface of a metal at room temperature, productivity may be reduced and cost may be increased. Therefore, gold, silver, copper and solder are preferable from the viewpoint of suppressing the formation of the oxide film, and gold and silver. , Solder is more preferable, and gold and silver are more preferable.

  Gold, silver, copper, solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, etc.), tin, nickel, etc. are mainly formed on the surfaces of the wiring 15 and the bumps 32. The metal layer as a component may be formed by plating, for example. This metal layer may be composed of only a single component or may be composed of a plurality of components. Further, the metal layer may have a structure in which a single layer or a plurality of metal layers are laminated.

  Further, in the semiconductor device of this embodiment, a plurality of structures (packages) as shown in the semiconductor devices 100 to 400 may be stacked. In this case, the semiconductor devices 100 to 400 include gold, silver, copper, solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper), tin, nickel. They may be electrically connected to each other by bumps, wires, etc.

  As a method of stacking a plurality of semiconductor devices, as shown in FIG. 4, for example, TSV (Through-Silicon Via) technology can be cited. FIG. 4 is a schematic cross-sectional view showing another embodiment of the semiconductor device of the present invention, which is a semiconductor device using the TSV technique. In the semiconductor device 500 shown in FIG. 4, the wiring 15 formed on the interposer 50 is connected to the wiring 15 of the semiconductor chip 10 via the connection bumps 30, so that the semiconductor chip 10 and the interposer 50 are flip-chip connected. ing. A void between the semiconductor chip 10 and the interposer 50 is filled with a cured product of an adhesive (first adhesive and second adhesive) without any gap, and constitutes the sealing portion 40. On the surface of the semiconductor chip 10 opposite to the interposer 50, the semiconductor chip 10 is repeatedly laminated via the wiring 15, the connection bumps 30, and the sealing portion 40. The wirings 15 on the pattern surfaces on the front and back of the semiconductor chip 10 are connected to each other by the through electrodes 34 filled in the holes penetrating the inside of the semiconductor chip 10. The material of the through electrode 34 may be copper, aluminum or the like.

  With such a TSV technology, it becomes possible to acquire a signal from the back surface of a semiconductor chip that is not normally used. Furthermore, since the through electrode 34 is vertically passed through the semiconductor chip 10, the distance between the semiconductor chips 10 facing each other, and the distance between the semiconductor chip 10 and the interposer 50 can be shortened, and flexible connection can be achieved. The film adhesive for semiconductors of the present embodiment can be applied as a film adhesive for semiconductors between the semiconductor chips 10 facing each other and between the semiconductor chips 10 and the interposer 50 in such a TSV technique.

  Further, in the bump forming method having a high degree of freedom such as the area bump chip technology, the semiconductor chip can be directly mounted on the mother board without the interposer. The film-shaped adhesive for semiconductors of this embodiment can be applied to the case where such a semiconductor chip is directly mounted on a mother board. In addition, the film adhesive for semiconductors of the present embodiment can be applied when sealing the gap between the substrates when the two printed circuit boards are laminated.

<Method of manufacturing semiconductor device>
The method for manufacturing the semiconductor device of this embodiment will be described below with reference to FIG. FIG. 5 is a diagram schematically showing an embodiment of the method for manufacturing a semiconductor device of the present invention. FIGS. 5A, 5B and 5C showing each step are the semiconductor device. The cross section of FIG.

  First, as shown in FIG. 5A, a solder resist 60 having an opening at a position where the connection bump 30 is formed is formed on the substrate 20 having the wiring 15. This solder resist 60 does not necessarily have to be provided. However, by providing the solder resist on the substrate 20, the generation of bridges between the wirings 15 can be suppressed, and the connectivity and insulation reliability can be improved. The solder resist 60 can be formed using, for example, a commercially available solder resist ink for a package. Specific examples of the commercially available solder resist ink for packaging include SR series (trade name, manufactured by Hitachi Chemical Co., Ltd.) and PSR4000-AUS series (trade name, manufactured by Taiyo Ink Manufacturing Co., Ltd.).

  Next, as shown in FIG. 5A, the connection bump 30 is formed in the opening of the solder resist 60. Then, as shown in FIG. 5B, the surface on the side of the second layer 41b containing the second adhesive is on the substrate 20 side on the substrate 20 on which the connection bumps 30 and the solder resist 60 are formed. The film-like adhesive for semiconductors (hereinafter, sometimes referred to as “film-like adhesive”) 41 of the present embodiment is attached to. The sticking of the film adhesive 41 can be performed by hot pressing, roll laminating, vacuum laminating, or the like. The supply area and thickness of the film adhesive 41 are appropriately set depending on the sizes of the semiconductor chip 10 and the substrate 20, the height of the connection bumps 30, and the like. The film adhesive 41 may be attached such that the surface of the first layer 41a containing the first adhesive is on the substrate 20 side.

  After the film adhesive 41 is attached to the substrate 20 as described above, the wiring 15 of the semiconductor chip 10 and the connection bump 30 are aligned with each other by using a connecting device such as a flip chip bonder. Subsequently, the semiconductor chip 10 and the substrate 20 are pressure-bonded while being heated at a temperature equal to or higher than the melting point of the connection bumps 30 to connect the semiconductor chip 10 and the substrate 20 as shown in FIG. The gap between the semiconductor chip 10 and the substrate 20 is sealed and filled by the sealing portion 40 made of a cured product of the adhesive 41. As described above, the semiconductor device 600 is obtained.

  In the method for manufacturing a semiconductor device according to the present embodiment, after the alignment, the connection bumps 30 are temporarily fixed (a state in which a film adhesive for semiconductors is interposed) and heat-treated in a reflow furnace to melt the connection bumps 30 and to form a semiconductor. The chip 10 and the substrate 20 may be connected. At the stage of temporary fixing, it is not always necessary to form a metal joint, so compared with the above-mentioned method of crimping while heating, crimping with a low load, for a short time, and at a low temperature may be sufficient, improving productivity and connecting. It is possible to suppress deterioration of the part.

  Also, after connecting the semiconductor chip 10 and the substrate 20, heat treatment may be performed in an oven or the like to further improve the connectivity and insulation reliability. The heating temperature is preferably a temperature at which the film adhesive is cured, and more preferably a temperature at which the film adhesive is completely cured. The heating temperature and the heating time are appropriately set.

  In the method of manufacturing the semiconductor device of this embodiment, the semiconductor chip 10 and the substrate 20 may be connected after the film adhesive 41 is attached to the semiconductor chip 10.

  From the viewpoint of improving productivity, after supplying a semiconductor film adhesive to a semiconductor wafer in which a plurality of semiconductor chips 10 are connected to each other, the semiconductor film is adhered onto the semiconductor chip 10 by dicing into individual pieces. A structure provided with the agent may be obtained. The film adhesive for semiconductors may be supplied so as to embed the wiring, bumps and the like on the semiconductor chip 10 by a sticking method such as hot pressing, roll laminating and vacuum laminating. In this case, since the supply amount of the resin becomes constant, the productivity is improved, and it is possible to suppress the occurrence of voids and the dicing property deterioration due to insufficient embedding.

  The connection load is set in consideration of variations in the number and height of the connection bumps 30, the amount of deformation of the connection bumps 30 due to pressure, or the wiring that receives the bumps of the connection portion. The connection temperature is preferably such that the temperature of the connection portion is equal to or higher than the melting point of the connection bump 30, but may be a temperature at which a metal bond of each connection portion (bump and wiring) is formed. When the connection bumps 30 are solder bumps, about 240 ° C. or higher is preferable.

  The connection time at the time of connection varies depending on the constituent metal of the connection portion, but a shorter time is preferable from the viewpoint of improving productivity. When the connection bumps 30 are solder bumps, the connection time is preferably 20 seconds or less, more preferably 10 seconds or less, and further preferably 5 seconds or less. In the case of copper-copper or copper-gold metal connection, the connection time is preferably 60 seconds or less.

  Even in the flip-chip connection parts having various package structures described above, the film-like adhesive for a semiconductor of the present embodiment exhibits excellent reflow resistance, connection property, and insulation reliability.

  Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  Hereinafter, the content of the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

(Examples 1 to 8 and Comparative Examples 1 to 10)
<Preparation of Single Layer Film with First Layer>
The compounds used to make the monolayer film with the first layer are shown below.
[Epoxy resin]
EP1032 (polyfunctional solid epoxy containing triphenol methane skeleton, manufactured by Mitsubishi Chemical Corporation, trade name "jER1032H60", "jER" is a registered trademark (the same applies below))
・ YL983U (bisphenol F type liquid epoxy, manufactured by Mitsubishi Chemical Corporation, trade name "jERYL983U")

[Curing agent]
・ 2P4MHZ (2-phenyl-4-methyl-5-hydroxymethylimidazole, manufactured by Shikoku Chemicals Co., Ltd., trade name "2P4MHZ-PW")

[Flux agent]
・ Glutaric acid (Tokyo Kasei Co., Ltd., melting point approx. 98 ° C.)
2-Methylglutaric acid (manufactured by Sigma-Aldrich Co., melting point: about 78 ° C.)
・ 3-Methylglutaric acid (Tokyo Kasei Co., Ltd., melting point approx. 87 ° C)

[Polymer component]
FX293 (phenoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name, weight average molecular weight Mw: about 45,000))
LA2250 (triblock copolymer of polymethylmethacrylate and polybutylacrylate, manufactured by Kuraray Co., Ltd., trade name "Clarity LA2250", "Clarity" is a registered trademark)

[Filler]
・ SE2050 (silica filler, manufactured by Admatechs Co., Ltd., trade name, average particle size: 0.5 μm)
EXL2655 (organic filler, manufactured by Rohm and Haas Japan Co., Ltd., trade name "Paraloid EXL-2655", core-shell type organic fine particles, "Paraloid" is a registered trademark)

[Coupling agent]
SH6040 (silane coupling agent, 3-glycidoxytrimethoxysilane, Toray Dow Corning Silicone Co., Ltd., trade name)

  The epoxy resin, the curing agent, the flux agent, the polymer component, the filler, and the coupling agent in the compounding amounts (units: parts by mass) shown in Table 1 were used for the NV value ([mass of paint after drying] / [coating before drying] [Partial mass] × 100) was added to an organic solvent (methyl ethyl ketone) such that it was 60%. After that, beads of Φ1.0 mm and beads of Φ2.0 mm were added in the same amount as the solid content (epoxy resin, curing agent, flux agent, polymer component, filler and coupling agent), and a bead mill (Fritsch Japan KK) was added. The mixture was stirred for 30 minutes with a planetary pulverizer P-7). After stirring, the beads were removed by filtration to prepare coating varnishes a1 to a4 containing the first adhesive.

  The obtained coating varnishes a1 to a4 are coated on a base film (manufactured by Teijin DuPont Films Ltd., trade name "Purex A54") with a small precision coating device (manufactured by Rensai Seiki Co., Ltd.). Then, it was dried (80 ° C./10 min) in a clean oven (manufactured by ESPEC Co., Ltd.) to obtain a single-layer film including the first layer (film adhesive A) having the thickness shown in Table 2.

<Production of Single Layer Film with Second Layer>
The compounds used to make the monolayer film with the second layer are shown below.

[Acrylic compound]
EA-0200 (acrylate having a fluorene skeleton, manufactured by Osaka Gas Chemicals Co., Ltd., trade name "OGSOL EA-0200", functional group number: 2, "OGSOL" is a registered trademark)
EA-1020 (acrylate having bisphenol A type skeleton, manufactured by Shin-Nakamura Chemical Co., Ltd., trade name)

[Thermal radical generator]
・ Park Mill D (Dicumyl peroxide, NOF Corporation, trade name, "Park Mill" is a registered trademark)

[Polymer component]
KH-CT-865 (acrylic resin, manufactured by Hitachi Chemical Co., Ltd., trade name, weight average molecular weight Mw: 100000)
-Urethane resin (manufactured by DIC Covestro Polymer Co., Ltd., trade name "Pandex T-8175N", "Pandex" is a registered trademark)

[Filler]
・ SE2050 (silica filler, manufactured by Admatechs Co., Ltd., trade name, average particle size: 0.5 μm)
EXL2655 (organic filler, manufactured by Rohm and Haas Japan Co., Ltd., trade name "Paraloid EXL-2655", core-shell type organic fine particles, "Paraloid" is a registered trademark)

[Coupling agent]
SH6040 (silane coupling agent, 3-glycidoxytrimethoxysilane, Toray Dow Corning Silicone Co., Ltd., trade name)

  Acrylic compounds, polymer components, fillers and coupling agents in the blending amounts (unit: parts by mass) shown in Table 3 were added to an organic solvent (methyl ethyl ketone) so that the NV value was 60%. After that, Φ1.0 mm beads and Φ2.0 mm beads were added in the same amount as the solid content (acrylic compound, polymer component, filler and coupling agent), and a bead mill (Fritsch Japan Co., Ltd., planetary pulverizer P) was added. It stirred at -7) for 30 minutes. After stirring, the beads were removed by filtration. Next, a heat radical generator was added to the obtained mixture and mixed by stirring to prepare coating varnishes b1 to b3 containing the second adhesive.

  The obtained coating varnishes b1 to b3 are coated on a base film (manufactured by Teijin DuPont Films Co., Ltd., trade name "Purex A54") with a small precision coating device (Narui Seiki) and a clean oven. After drying (manufactured by ESPEC Co., Ltd.) (80 ° C./10 min), a single-layer film having a second layer (film adhesive B) having a thickness shown in Table 4 was obtained.

<Production of two-layer film>
Two of the single-layer films produced above were prepared as a first film and a second film, and the first film and the second film were laminated at 50 ° C., and then the first film side The base film was peeled off, and a base film (6331-00, manufactured by Hitachi Maxell, Ltd.) provided with an adhesive layer was laminated on the surface from which the base film was peeled off. Thereby, a two-layer film including a film adhesive C having a total thickness of 40 μm (a laminated body including a layer derived from the first film and a layer derived from the second film) was obtained. The combinations of single-layer films were as shown in Tables 5 and 6.

<Evaluation 1: Measurement of chlorine ion concentration>
Using the single-layer film and the two-layer film produced above, a film adhesive A (first layer), a film adhesive B (second layer) and a film adhesive C (derived from the first film) Of the second layer and the layer derived from the second film), the chloride ion concentration was measured by the following method. First, the single-layer film and the two-layer film produced above were respectively heated at 240 ° C. for 60 minutes in an air atmosphere to obtain cured products of the film adhesives A to C. The obtained cured product was pulverized into a pulverized product, and the obtained pulverized product was passed through a Tyler sieve 200 mesh. A mixture was prepared by mixing 1 g of the granular material that passed through the sieve with 40 g of ion-exchanged water. The prepared mixture was placed in a container and sealed. In this closed container, it was boiled at 121 ° C. under 2 atmospheres for 48 hours. After the particulate matter was removed from the mixture after boiling to obtain extracted water, the chloride ion concentration of the extracted water was measured by an ion chromatography method. The results are shown in Tables 5 and 6.

<Evaluation 2: Insulation reliability evaluation (HAST test)>
The film-like adhesive C (thickness: 40 μm) obtained in Examples and Comparative Examples was attached to a comb-shaped electrode evaluation TEG (manufactured by Hitachi Chemical Co., Ltd., wiring pitch: 40 μm), and a clean oven (manufactured by Espec Corporation). ), The film adhesive C was cured by heating at 175 ° C. for 2 hours. At this time, the film adhesive C was attached to the comb-shaped electrode evaluation TEG so that the layer derived from the second film was in contact with the comb-shaped electrode evaluation TEG. Thereby, a structure including a cured product of the film adhesive C on the comb-shaped electrode evaluation TEG was obtained. The obtained structure is installed in a high-acceleration life test apparatus (manufactured by Hirayama Seisakusho, trade name “PL-422R8”, condition: 130 ° C./85% RH / 200 hours, 5 V applied), and a HAST test is performed. It was The insulation resistance after 200 hours was measured, and when the insulation resistance was 10 ⁸ Ω or more, “A” was set, and when the insulation resistance was 10 ⁷ Ω or more and less than 10 ⁸ Ω, “B” was set, and the value was less than 10 ⁷ Ω. The case where there was was evaluated as "C". The results are shown in Tables 5 and 6.

<Evaluation 3: Connectivity evaluation>
The film-like adhesive C obtained in Examples and Comparative Examples was cut out into a predetermined size (length 8 mm × width 8 mm × thickness 40 μm), and the obtained film-like sample was used as a glass epoxy substrate with a copper wiring (glass epoxy group). Material thickness: 420 μm, copper wiring thickness: 9 μm). At this time, the film adhesive C was attached to the glass epoxy substrate with copper wiring so that the layer derived from the second film was in contact with the glass epoxy substrate with copper wiring. Next, a semiconductor chip with solder bumps (chip size: vertical 7.3 mm × horizontal 7.3 mm × thickness 0.15 mm, bump height: total height of copper pillars and solder of about 40 μm, number of bumps 328) From the film adhesive C side, it was mounted with a flip mounting device (manufactured by Panasonic Corporation, trade name “FCB3”) (mounting conditions: pressure bonding head temperature 350 ° C., pressure bonding time 5 seconds, pressure bonding pressure 0.5 MPa). As a result, a semiconductor device was produced in which the glass epoxy substrate and the semiconductor chip with solder bumps were daisy chain connected.

  The connection resistance value of the manufactured semiconductor device was measured using a multimeter (manufactured by ADC Co., Ltd., trade name “R6871E”) to evaluate the initial conduction after mounting. When the connection resistance value is 10.0 Ω or more and 13.5 Ω or less, the connectivity is evaluated as “A”. When the connection resistance value exceeds 13.5 Ω and is 20 Ω or less, the connection resistance value is evaluated as “B”. Is larger than 20Ω, the connection resistance value is less than 10Ω, and the connection is open (when the resistance value is not displayed), it is evaluated as “C”. The results are shown in Tables 5 and 6.

<Evaluation 4: Flux activity evaluation>
Regarding the example in which the connectivity was good in the connectivity evaluation, the cross section of the connection portion was observed, and when the solder wetting on the upper surface of the Cu wiring was 90% or more, it was evaluated as “A”, and the solder wetting was 90. When it was less than%, it was evaluated as "B". The results are shown in Tables 5 and 6.

  In Examples 1 to 8, it was confirmed that excellent insulation reliability was obtained. It was also confirmed that when the film adhesive C (film adhesive for semiconductors) of Examples 1 to 8 was used, the connectivity after mounting was good and excellent flux activity was obtained.

  1, 41 ... Film adhesive for semiconductors, 2, 41a ... First layer, 3, 41b ... Second layer, 10 ... Semiconductor chip, 15 ... Wiring (connecting portion), 20 ... Board (wiring circuit board) , 30 ... Connection bumps, 32 ... Bumps (connection portions), 34 ... Through electrodes, 40 ... Sealing portion, 50 ... Interposer, 60 ... Solder resist, 100, 200, 300, 400, 500, 600 ... Semiconductor device.

Claims (8)

A first layer made of a first thermosetting adhesive containing a flux compound; and a second layer made of a second thermosetting adhesive provided on the first layer. ,
A film adhesive for semiconductors, which satisfies the following condition (A).
Condition (A): The film adhesive for semiconductors is heated in an air atmosphere at 240 ° C. for 60 minutes to obtain a cured product, the cured product is pulverized into a pulverized product, and the pulverized product is passed through a Tyler sieve 200 mesh. , 1 g of the granules that have passed through the sieve and 40 g of ion-exchanged water are mixed to form a mixture, and the mixture is boiled in a closed container under 2 atm at 121 ° C. for 48 hours, and the granules are boiled from the mixture. When the chlorine ion concentration of the extracted water obtained by removal is measured by an ion chromatography method, the chlorine ion concentration of the extracted water is 2 mass ppm or less.   2. The semiconductor according to claim 1, wherein a ratio of the thickness of the second layer to the total thickness of the first layer and the thickness of the second layer is 1/4 or more and 3/4 or less. Film adhesive.   The film adhesive for semiconductors according to claim 1, wherein the flux compound has a carboxyl group.   The film-like adhesive for semiconductors according to claim 1, wherein the flux compound has two or more carboxyl groups. The film-like adhesive for semiconductors according to claim 1, wherein the flux compound is a compound represented by the following formula (2).

[In the formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron-donating group, and n represents 0 or an integer of 1 or more. ]   The film-like adhesive for semiconductors according to claim 1, wherein the melting point of the flux compound is 150 ° C. or lower. A semiconductor device in which the respective connecting portions of the semiconductor chip and the printed circuit board are electrically connected to each other, or a method of manufacturing a semiconductor device in which the respective connecting portions of a plurality of semiconductor chips are electrically connected to each other,
A method for manufacturing a semiconductor device, comprising a step of sealing at least a part of the connection portion with the film adhesive for semiconductor according to claim 1. A semiconductor device in which the respective connecting portions of the semiconductor chip and the printed circuit board are electrically connected to each other, or a semiconductor device in which the respective connecting portions of the plurality of semiconductor chips are electrically connected to each other,
A semiconductor device, wherein at least a part of the connection portion is sealed with a cured product of the film adhesive for semiconductor according to any one of claims 1 to 6.

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