TW201904007A - Film-like adhesive for semiconductors, semiconductor device production method, and semiconductor device - Google Patents

Abstract

This film-like adhesive for semiconductors is provided with a first layer which comprises a first thermosetting adhesive containing a flux compound, and a second layer which is provided upon the first layer and comprises a second thermosetting adhesive containing substantially no flux compound.

Description

Film adhesive for semiconductor, method for manufacturing semiconductor device, and semiconductor device

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

Conventionally, when connecting a semiconductor chip to a substrate, a wire bonding method using thin metal wires such as gold wires has been widely used. On the other hand, in order to meet the requirements for higher functionality, higher integration, and higher speed of semiconductor devices, conductive bumps called bumps are formed on semiconductor wafers or substrates to directly connect semiconductor wafers to substrates. The flip-chip connection method (FC (flip chip) connection method) is being promoted.

For example, regarding the connection between semiconductor wafers and substrates, Chip On Board (COB) type connections commonly used in Ball Grid Array (BGA), Chip Size Package (CSP), etc. The method is also equivalent to the FC connection method. In addition, the FC connection method is also widely used as a chip-on-chip (COC) connection method in which connection portions (for example, bumps and wirings) are formed on a semiconductor wafer to connect the semiconductor wafers.

In addition, in a package that is strongly requested for further miniaturization, thinning, and high functionality, the above-mentioned connection method is used to laminate and multiply a chip stack type package and a package on package. , POP), Through-Silicon Via (TSV), etc. have also begun to spread widely. Such a multi-layer / multi-segmentation technique arranges semiconductor wafers and the like in a three-dimensional manner, and thus can reduce the size of the package compared to a method of arranging two-dimensionally. In addition, it is also effective in improving semiconductor performance, reducing noise, reducing packaging area, and saving power. Therefore, it has attracted attention as a next-generation semiconductor wiring technology.

In addition, in the connection of the connection parts, metal bonding is always used from the viewpoint of sufficiently ensuring connection reliability (for example, insulation reliability). As a main metal used in the connection portion (for example, a bump and a wiring), there are solder, tin, gold, silver, copper, nickel, and the like, and a conductive material including a plurality of these materials is also used. The metal used in the connection portion generates an oxide film due to surface oxidation, and impurities such as oxides are adhered to the surface. Therefore, impurities may be generated on the connection surface of the connection portion. If such impurities remain, the connection reliability (for example, insulation reliability) between the semiconductor wafer and the substrate or between the two semiconductor wafers may be reduced, and the advantages of using the connection method may be impaired.

In addition, as a method for suppressing the generation of these impurities, there are known methods such as an organic solderable protective layer (Organic Solderability Preservatives (OSP) treatment), which coat the connection portion with an anti-oxidation film, but the anti-oxidation The film may cause a decrease in solder wettability and a decrease in connectivity during the connection process.

Therefore, as a method for removing the oxide film and impurities, a method of using a single-layer film containing a flux in a semiconductor material has been proposed (for example, refer to Patent Document 1), using a thermosetting resin layer and an oxygen component And the like of a two-layer film of a thermoplastic resin layer (for example, refer to Patent Document 2). [Prior Art Literature] [Patent Literature]

Patent Document 1: International Publication No. 2013/125086 Patent Document 2: International Publication No. 2016/117350

[Problems to be Solved by the Invention] In addition, in the flip-chip package, in recent years, there has been further development toward higher functionality and higher integration. With higher functionality and higher integration, the space between wirings has become narrower, so connection reliability is likely to decrease.

In addition, in recent years, from the viewpoint of improving productivity, it is required to make the crimping time at the time of assembling a flip-chip package short. When the crimping time is shortened, if the film adhesive for semiconductors is not sufficiently hardened during crimping, the connection portion cannot be sufficiently protected, and connection failure may occur when the pressure of the crimping is released. Furthermore, when solder is used in the connection portion, if the film-like adhesive for semiconductors during crimping is not sufficiently hardened in a temperature range lower than the melting temperature of the solder, solder is generated when the temperature at the time of crimping reaches the solder melting temperature. Scattered and flowed, resulting in poor connection. On the other hand, when the film-shaped adhesive for semiconductors is hardened before the connection portions are brought into contact with each other by pressure bonding, a state in which the adhesive intervenes between the connection portions and connection failure occurs.

Therefore, an object of the present invention is to provide a film-shaped adhesive for semiconductors that can obtain excellent connection reliability even when the crimping time is short. Another object of the present invention is to provide a semiconductor device using such a film-like adhesive for semiconductors and a method for manufacturing the same. [Means for solving problems]

A film-shaped adhesive for semiconductors according to the present invention includes a first layer including a first thermosetting adhesive, the first thermosetting adhesive including a flux compound, and a second thermal layer provided on the first layer. The second layer of the curable adhesive, the second thermosetting adhesive does not substantially contain a flux compound.

According to the film-shaped adhesive for semiconductors of the present invention, the second layer is less susceptible to the influence of the flux compound, and therefore, it exhibits a characteristic that the connection portions are quickly and sufficiently cured after the connection portions contact each other through the second layer. In addition, as for the film-like adhesive described in Patent Document 2, there is a high possibility that the thermoplastic resin is softened at a high temperature such as at the time of crimping to cause problems such as peeling, and there are problems in terms of reliability. On the one hand, such a problem is unlikely to occur in the film-shaped adhesive for semiconductors of the present invention. For these reasons, according to the film-shaped adhesive for semiconductors of the present invention, excellent connection reliability (for example, insulation reliability) can be obtained even when pressure bonding is performed at a high temperature for a short time. Moreover, according to the film-shaped adhesive for semiconductors of this invention, since a crimping time can be shortened, productivity can be improved. In addition, according to the film-shaped adhesive for semiconductors of the present invention, a flip-chip package can be easily made highly functional and highly integrated.

In addition, when the conventional adhesive for semiconductors (for example, the film-like adhesive described in Patent Document 1) has a crimping time of a short time, it is subjected to high-temperature crimping in a state where the adhesive for semiconductors is not sufficiently hardened. Sometimes voids are generated, and sometimes peeling occurs inside the package starting from the voids. When the peeling inside the package becomes large, stress acts on the connection portion and cracks occur. Therefore, peeling inside the package causes poor connection of the package. In contrast, the film-shaped adhesive for semiconductors according to the present invention can be sufficiently hardened in a short period of time, and therefore, the generation of voids can be easily suppressed. In addition, in the film-like adhesive for semiconductors of the present invention, the second layer that does not substantially contain the flux compound hardens rapidly. Therefore, even if micropores are generated, the expansion of the pores is suppressed, and it is difficult to produce a visible degree The size of the pores. These cases can be regarded as one of the reasons for obtaining excellent bonding reliability by the film-shaped adhesive of the present invention.

In addition, when a flip-chip package is produced using a conventional film adhesive, the adhesive may ooze out of the periphery of the wafer because the adhesive is not cured in a short time. The bleeding of such an adhesive will hinder the mounting of adjacent wafers, resulting in a reduction in the number of packages that can be mounted per wafer. That is, if bleeding of the adhesive from the periphery of the wafer occurs, the productivity is lowered. In addition, if the amount of exuding of the adhesive is excessive, the exuded adhesive may spread on the mounted wafer, which may cause damage to the wafer mounted when another wafer is further mounted on the wafer. On the other hand, the film-shaped adhesive for semiconductors according to the present invention can be sufficiently hardened in a short time, so that the occurrence of bleeding of the adhesive can be suppressed.

In addition, in recent years, as a metal of the connection portion, for the purpose of cost reduction, there is a tendency to use solder, copper, or the like instead of gold or the like that is not easily corroded. Furthermore, the surface treatment of wiring and bumps is also aimed at reducing the cost, and there is a tendency to use solder, copper, etc. instead of gold, which is not easily corroded, and to perform processes such as OSP (Organic Solderability Preservative) treatment. In the flip-chip package, in addition to narrowing the pitch and increasing the number of pins, such cost reduction has been promoted. Therefore, there is a tendency to use a metal that is easily corroded and has reduced insulation properties, and the insulation reliability is likely to decrease. On the other hand, according to the film adhesive for semiconductors of the present invention, it is possible to suppress a decrease in insulation reliability with respect to the metal.

The curing reaction rate after the second thermosetting adhesive is held at 200 ° C. for 5 seconds is preferably 80% or more. In this case, even when pressure bonding is performed at a high temperature for a short time, more excellent connection reliability can be obtained.

The second thermosetting adhesive preferably contains a radical polymerizable compound and a thermal radical generator. In this case, since the curing speed is very excellent, even when the compression bonding is performed at a high temperature for a short time, voids are hardly generated, and more excellent connection reliability can be obtained.

The thermal radical generator is preferably a peroxide. In this case, since further excellent operability and storage stability can be obtained, it is easy to obtain further excellent connection reliability.

The radical polymerizable compound is preferably a (meth) acrylic compound. In this case, it is easy to obtain further excellent connection reliability.

The (meth) acrylic compound preferably has a fluorene-type skeleton. In this case, it is easy to obtain further excellent connection reliability.

The flux compound preferably has a carboxyl group, and more preferably has two or more carboxyl groups. In this case, it is easy to obtain further excellent connection reliability.

The flux compound is preferably a compound represented by the following formula (2). In this case, it is easy to obtain further excellent connection reliability. [Chemical 1] [In formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron donating group, and n represents an integer of 0 or more]

The melting point of the flux compound is preferably 150 ° C or lower. In this case, when the thermocompression bonding is performed, the flux is melted before the adhesive is hardened, and an oxide film such as solder is reduced and removed. Therefore, further excellent connection reliability is easily obtained.

The first thermosetting adhesive preferably contains a hardener, and more preferably the hardener is an imidazole-based hardener. In this case, it is easy to obtain more excellent connection reliability.

A method of manufacturing a semiconductor device according to the present invention is a method of manufacturing a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a method of manufacturing a semiconductor device in which connection portions of multiple semiconductor wafers are electrically connected to each other The method for manufacturing a device includes a step of sealing at least a part of a connection portion using the film-like adhesive for semiconductors. According to the method for manufacturing a semiconductor device according to the present invention, a semiconductor device having excellent connection reliability (for example, insulation reliability) can be obtained even when pressure bonding is performed at a high temperature for a short time. That is, according to the manufacturing method of the present invention, a semiconductor device excellent in connection reliability (for example, insulation reliability) can be manufactured in a short time.

The semiconductor device of the present invention is a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other, wherein at least a part of the connection portion is described by The cured product of the film-shaped adhesive for semiconductors is sealed. The semiconductor device is excellent in continuous reliability (for example, insulation reliability). [Effect of the invention]

According to the present invention, it is possible to provide a film-shaped adhesive for a semiconductor that can obtain excellent connection reliability even when the crimping time is short. In addition, according to the present invention, a semiconductor device using such a film-shaped adhesive for semiconductors and a method for manufacturing the same can be provided.

In this specification, "(meth) acrylate" means at least one of an acrylate and a corresponding methacrylate. The same applies to other similar expressions such as "(meth) acrylfluorenyl" and "(meth) acrylic acid". In addition, the numerical range shown using "~" means the range which includes the numerical value described before and after "~" as a minimum value and a maximum value, respectively.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings, the same or corresponding parts are denoted by the same symbols, and repeated explanations are omitted. In addition, a positional relationship such as up, down, left, right, etc. is considered to be based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to the ratios shown in the drawings.

<Film-shaped adhesive for semiconductors> The film-shaped adhesive for semiconductors of this embodiment includes a first layer (a first thermosetting adhesive containing a flux compound (hereinafter also simply referred to as a "first adhesive")) A flux-containing layer) and a second layer (excluding a second thermosetting adhesive (hereinafter also simply referred to as a "second adhesive")) provided on the first layer and containing substantially no flux compound Flux layer).

The film-shaped adhesive for semiconductors of this embodiment is, for example, a non-conductive adhesive (a film-shaped non-conductive adhesive for semiconductors), a semiconductor device which is electrically connected to each connection portion of a semiconductor wafer and a printed circuit board, or In a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other, at least a part of the connection portions is sealed.

According to the film-shaped adhesive for semiconductors of this embodiment, in the manufacture of the semiconductor device, even during the crimping time (for example, the crimping time in the step of crimping to bond a semiconductor wafer to a printed circuit board) ) When the time is shortened (for example, when the crimping time is set to 5 seconds or less), excellent connection reliability can also be obtained.

(First Adhesive) The first adhesive contains, for example, a thermosetting component and a flux compound. Examples of the thermosetting component include a thermosetting resin and a curing agent. Examples of the thermosetting resin include an epoxy resin, a phenol resin (except when it is contained as a curing agent), a polyimide resin, and the like. Among these, the thermosetting resin is preferably an epoxy resin. In addition, the film-shaped adhesive for semiconductors according to this embodiment may contain a polymer component having a weight average molecular weight of 10,000 or more and a filler, as necessary.

Hereinafter, the first adhesive contains an epoxy resin (hereinafter, referred to as "(a) component"), a hardener (hereinafter, referred to as "(b) component" as appropriate), a flux compound (hereinafter, referred to as " In some cases, it is called "(c) component"), and if necessary, a polymer component having a weight-average molecular weight of 10,000 or more (hereinafter, referred to as "(d) component") and filler (hereinafter, referred to as "( e) An embodiment of the component ") will be described.

[(A) Component: Epoxy resin] As the epoxy resin, if it has two or more epoxy groups in the molecule, it can be used without particular limitation. As component (a), for example, bisphenol A epoxy resin, bisphenol F epoxy resin, naphthalene epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin, and phenol can be used. Aralkyl type epoxy resin, biphenyl type epoxy resin, triphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin and various multifunctional epoxy resins. These may be used alone or as a mixture of two or more.

From the viewpoint of suppressing the decomposition of the component (a) at a high temperature to generate volatile components, when the temperature at the time of the connection is 250 ° C, it is preferable to use a thermal weight reduction rate of 5% at 250 ° C. When the temperature of the following epoxy resin is 300 ° C., it is preferable to use an epoxy resin having a thermal weight loss rate of 300 ° C. or less.

The content of the component (a) on the basis of the total mass of the first adhesive is, for example, 5% to 75% by mass, preferably 10% to 50% by mass, and more preferably 15% to 35% by mass.

[(B) Component: Hardener] Examples of the (b) component include a phenol resin-based hardener, an acid anhydride-based hardener, an amine-based hardener, an imidazole-based hardener, and a phosphine-based hardener. When the component (b) contains a phenolic hydroxyl group, an acid anhydride, an amine, or an imidazole, it exhibits a flux activity that suppresses the generation of an oxide film in the connection portion, thereby improving connection reliability and insulation reliability. Each of the hardeners will be described below.

(I) Phenolic resin-based hardener is not particularly limited as long as it has two or more phenolic hydroxyl groups in the molecule. For example, phenol novolac resin, cresol novolac resin, Phenol aralkyl resin, cresol naphthol formaldehyde polycondensate, triphenylmethane type polyfunctional phenol resin and various polyfunctional phenol resins. These may be used alone or as a mixture of two or more.

From the viewpoints of good hardenability, adhesion, and storage stability, the equivalent ratio of the phenol resin-based hardener to the component (a) (the number of moles of phenolic hydroxyl groups of the phenol resin-based hardener / The mole number of the epoxy group in the (a) component is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and even more preferably 0.5 to 1.0. If the equivalence ratio is 0.3 or more, the hardenability will be improved, and the adhesion force will tend to increase. If it is 1.5 or less, the unreacted phenolic hydroxyl group will not remain excessively, the water absorption rate is suppressed to a low value, and the insulation reliability is improved Propensity.

(Ii) Acid anhydride-based hardener As the acid anhydride-based hardener, for example, methylcyclohexanetetracarboxylic dianhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic dianhydride, and ethyl Diol trimellitic anhydride. These may be used alone or as a mixture of two or more.

From the viewpoint of good hardenability, adhesion, and storage stability, the equivalent ratio of the acid anhydride-based hardener to the component (a) (the number of moles of the acid anhydride group of the acid anhydride-based hardener / (a) The mole number of the epoxy group in the component) is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and even more preferably 0.5 to 1.0. If the equivalence ratio is 0.3 or more, the hardenability is improved and the adhesion force is increased. If it is 1.5 or less, the unreacted acid anhydride does not remain excessively, the water absorption is suppressed to a low value, and the insulation reliability tends to be improved. .

(Iii) Amine-based hardener As the amine-based hardener, for example, dicyandiamine can be used.

From the viewpoints of good hardenability, adhesion, and storage stability, the equivalent ratio of the amine-based hardener to the component (a) (the number of moles of active hydroxyl groups of the amine-based hardener / (a) The mole number of the epoxy group in the component) is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and even more preferably 0.5 to 1.0. If the equivalence ratio is 0.3 or more, the hardenability will be improved and the adhesion force will tend to increase. If it is 1.5 or less, unreacted amine will not remain excessively, and the insulation reliability tends to be improved.

(Iv) Imidazole-based hardeners Examples of the imidazole-based hardener include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl- 2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitic acid Ester, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-homo 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-mesytriazine isotricyanic acid adduct, 2-phenylimidazole isotricyanic acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4 -Methyl-5-hydroxymethylimidazole, and an adduct of epoxy resin and imidazoles. Among these, 1-cyanoethyl-2-undecylimidazole and 1-cyano-2-phenylimidazole are preferable from a viewpoint of excellent hardenability, storage stability, and connection reliability. , 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'-ethyl-4'-methylimidazolyl- (1' )]-Ethyl-tris-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1 ')]-ethyl-s-triazine isotricyanic acid adduct, 2-phenylimidazole isotricyanic acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-hydroxymethylimidazole. These can be used alone or in combination of two or more. In addition, a latent curing agent obtained by microencapsulating these may be used.

The content of the imidazole-based hardener is preferably from 0.1 to 20 parts by mass, and more preferably from 0.1 to 10 parts by mass based on 100 parts by mass of the component (a). When the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curability tends to be improved. In addition, if 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 excluded. As a result, since the 1st adhesive agent can be suppressed from hardening in the state which interposed between solder and a connection part, connection failure is hard to occur.

(V) Phosphine-based hardener Examples of the phosphine-based hardener include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra (4-methylphenyl) borate, and tetrabenzene Hydrazone (4-fluorophenyl) borate.

The content of the phosphine-based hardener 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 component (a). When the content of the phosphine-based hardener is 0.1 parts by mass or more, the hardenability tends to be improved. When the content is 10 parts by mass or less, the first adhesive does not harden before the formation of the metal joint, and connection failure is less likely to occur.

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

In the case where the first adhesive contains a phenol resin-based hardener, an acid anhydride-based hardener, or an amine-based hardener as the component (b), the flux activity to remove the oxide film is shown, and connection reliability can be further improved.

[Component (c): Flux Compound] The component (c) is a compound having a flux activity, and functions as a flux in the first adhesive. As the component (c), a known flux compound can be used without particular limitation as long as the oxide film on the surface of solder or the like is reduced and removed to facilitate metal bonding. As component (c), one type of flux compound may be used alone, or two or more types of flux compounds may be used in combination. However, the component (c) does not include a hardener as the component (b).

From the viewpoint of obtaining sufficient flux activity and obtaining more excellent connection reliability, the flux compound preferably has a carboxyl group, and more preferably has two or more carboxyl groups. Among these, a compound having two carboxyl groups is preferred. Compared with a compound having one carboxyl group (monocarboxylic acid), a compound having two carboxyl groups is less volatile even at a high temperature at the time of connection, which can further suppress the generation of pores. In addition, when a compound having two carboxyl groups is used, it is possible to further suppress the increase in viscosity of the film-like adhesive for semiconductors during storage and connection operations, etc., compared to the case of using a compound having three or more carboxyl groups, and it is possible to make The connection reliability of the semiconductor device is further improved.

As the flux compound having a carboxyl group, a compound having a group represented by the following formula (1) can be preferably used. [Chemical 2]

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

From the viewpoint of excellent reflow resistance and the viewpoint of further excellent connection reliability, it is preferable that R ¹ is an electron donor. In this embodiment, in addition to the epoxy resin and the hardener, the first adhesive further contains a compound in which R ¹ is an electron-donating group among compounds having a group represented by formula (1), whereby Even when applied as a film-like adhesive for semiconductors in a flip-chip connection method in which metal bonding is performed, a semiconductor device having more excellent reflow resistance and connection reliability can be produced.

In order to improve reflow resistance, it is necessary to suppress a decrease in adhesive force after moisture absorption at high temperatures. A carboxylic acid has been conventionally used as a flux compound, but the present inventors believe that the conventional flux compound has a decrease in adhesion due to the following reasons.

Generally, an epoxy resin reacts with a hardener to perform a hardening reaction, but in this case, a carboxylic acid as a flux compound is included in the hardening reaction. That is, the epoxy group of an epoxy resin may react with the carboxyl group of a flux compound, and an ester bond may be formed. The ester bond is liable to undergo hydrolysis or the like due to moisture absorption, and the decomposition of the ester bond is considered to be a cause of a decrease in adhesive force after moisture absorption.

On the other hand, among the compounds having a group represented by formula (1), the first adhesive contains 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. In the case where the flux activity is sufficiently obtained by the carboxyl group, and even when the ester bond is formed, the electron density of the ester bond portion is increased by the electron-donating group, and the decomposition of the ester bond is suppressed. . In addition, it is considered that since a substituent (electron-donating group) exists near the carboxyl group, the reaction between the carboxyl group and the epoxy resin is suppressed due to steric hindrance, and an ester bond is not easily formed.

For these reasons, when a first adhesive agent containing a compound in which R ¹ is an electron-donating group among compounds further having a group represented by formula (1) is used, it is difficult to generate a composition due to moisture absorption or the like. The change can maintain excellent adhesion. In addition, the effect can also make the hardening reaction of the epoxy resin and the hardener difficult to be hindered by the flux compound. With this effect, the connection between the epoxy resin and the hardener can be expected to be brought about by the sufficient progress of the hardening reaction. The effect of sexual improvement.

When the electron-donating property of the electron-donating group becomes strong, the effect of suppressing the decomposition of the ester bond tends to be easily obtained. In addition, if the steric hindrance of the electron-donating group is large, the effect of suppressing the reaction between the carboxyl group and the epoxy resin is easily obtained. The electron-donating group preferably has electron-donating properties and steric hindrance with good balance.

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 does not easily react with other components (for example, the epoxy resin of the component (a)). Specifically, it is preferably an alkyl group, a hydroxyl group, or an alkoxy group, and more preferably an alkyl group. .

The alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 1 to 5 carbon atoms. As the number of carbon atoms having an alkyl group increases, the electron donating property and the steric hindrance tend to increase. The alkyl group having a carbon number within the above-mentioned range is excellent in the electron-donating property and the balance of steric hindrance. Therefore, the effect of the present invention can be more significantly exhibited by the alkyl group.

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 equal to or less than the carbon number of the main chain of the flux compound from the viewpoint of the balance between the electron donating property and the 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 preferably the carbon number of the main chain of the flux compound. (N + 1) or less.

The alkoxy group is preferably an alkoxy group having 1 to 10 carbon atoms, and more preferably an alkoxy group having 1 to 5 carbon atoms. As the number of carbon atoms having an alkoxy group increases, the electron donor property and the steric hindrance tend to increase. The alkoxy group having a carbon number within the above-mentioned range is excellent in the electron donor property and the balance of steric hindrance. Therefore, the effect of the present invention can be more significantly exhibited by the alkoxy group.

The alkyl 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 in the alkoxy group is preferably equal to or less than the number of carbon atoms in the main chain of the flux compound from the viewpoint of the balance between the electron donor property and the 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 preferably the same as that of the main chain of the flux compound. Carbon number (n + 1) or less.

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

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

As the flux compound having two carboxyl groups, a compound represented by the following formula (2) can be suitably used. According to the compound represented by the following formula (2), reflow resistance and connection reliability of a semiconductor device can be further improved.

[Chemical 3]

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

Of formula R ¹ and R (1) ¹ is the same meaning. The electron donating property represented by R ² is the same as the example of the electron donating property group described as R ¹ . For the same reason as described 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, compared with the case where n is 0, the flux compound is less volatile even due to the high temperature at the time of connection, and the generation of voids can be further suppressed. In addition, n in the formula (2) is preferably 15 or less, more preferably 11 or less, or 6 or 4 or less. When n is 15 or less, further excellent connection reliability can be obtained.

The flux compound is more preferably a compound represented by the following formula (3). According to the compound represented by the following formula (3), reflow resistance and connection reliability of a semiconductor device can be further improved.

[Chemical 4]

In formula (3), R ¹ and R ² each independently represent a hydrogen atom or an electron-donating group, and m represents an integer of 0 or 1 or more. R ^(2), R ¹ and R ² in Formula ¹ and R ² are the same meanings.

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

In formula (3), R ¹ and R ² may be a hydrogen atom or an electron-donating group. From the viewpoint of obtaining further excellent connection reliability, at least one of R ¹ and R ² is preferably an electron-donating group. When R ¹ is an electron-donating group and R ² is a hydrogen atom, the melting point tends to be lowered, and the connection reliability of the semiconductor device may be further improved in some cases. In addition, if R ¹ and R ² are different electron-donating groups, the melting point tends to be lower than when R ¹ and R ² are the same electron-donating group, and the semiconductor device may be further improved in some cases. Connection reliability.

In addition, in formula (3), if R ¹ and R ^{2 have} the same electron-donating group, there is a tendency that the melting point becomes a symmetric structure, but in this case, the effects of the present invention can be sufficiently obtained. In particular, when the melting point is sufficiently lower than 150 ° C., even if R ¹ and R ² are the same group, the same degree of connection reliability can be obtained as when R ¹ and R ² are different groups.

As the flux compound, for example, a compound selected from the group consisting of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, and dodecanedioic acid can be used. Dicarboxylic acids and compounds in which an electron-donating group is substituted at the 2-position of these dicarboxylic acids.

The melting point of the flux compound is preferably 150 ° C or lower, more preferably 140 ° C or lower, and even more preferably 130 ° C or lower. Such a flux compound easily exhibits a flux activity sufficiently before the hardening reaction of an epoxy resin and a hardener occurs. Therefore, according to the semiconductor film-shaped adhesive using the first adhesive containing such a flux compound, a semiconductor device having further excellent connection reliability can be realized. The melting point of the flux compound is preferably 25 ° C or higher, and more preferably 50 ° C or higher. The flux compound is preferably solid at room temperature (25 ° C).

The melting point of a flux compound can be measured using a general melting point measuring device. By pulverizing a sample for measuring the melting point into a fine powder and using a small amount, it is possible to obtain a melting point while reducing variations in temperature in the sample. As a container for a sample, a capillary tube having one of its ends closed is used in many cases, but depending on the measurement device, it may be sandwiched between two cover glasses for microscopes as a container. In addition, if the temperature is increased sharply, a temperature gradient will occur between the sample and the thermometer, which will cause measurement errors. Therefore, the temperature at the time of measuring the melting point is preferably measured at a rise rate of 1 ° C per minute or less. .

As described above, since the sample for measuring the melting point is prepared as a fine powder, the sample before melting is opaque due to diffuse reflection in the surface. Generally, the temperature at which the appearance of the sample starts to become transparent is the lower limit point of the melting point, and the temperature at which it completely melts is the upper limit point. There are various types of measuring devices. The most classic device is a device in which a capillary tube filled with a sample is mounted on a dual-tube thermometer, and the heating is performed using a warm bath. In order to attach a capillary tube to a dual-tube thermometer, a highly viscous liquid is used as a warming liquid. In most cases, concentrated sulfuric acid or silicone oil is used, and the sample is moved to the vicinity of the accumulation part at the top of the thermometer. . In addition, the melting point measuring device may be a device that performs heating using a metal heat block, prepares a heating while measuring light transmittance, and automatically determines a melting point.

In this 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.

On the basis of the total mass of the first adhesive, the content of the component (c) is preferably 0.5% by mass to 10% by mass, and more preferably 0.5% by mass to 5% by mass.

[(D) Component: Polymer component having a weight average molecular weight of 10,000 or more] The first adhesive contains a polymer component (component (d)) having a weight average molecular weight of 10,000 or more as necessary. The first adhesive containing the component (d) is further excellent in heat resistance and film formability.

Examples of the component (d) include phenoxy resin, polyimide resin, polyimide resin, polycarbodiimide resin, cyanate resin, acrylic resin, polyester resin, polyethylene resin, Polyether 碸 resin, polyether 醯 imine resin, polyvinyl acetal resin, urethane resin and acrylic rubber. Among these, from the viewpoint of excellent heat resistance and film formability, phenoxy resin, polyimide resin, urethane resin, acrylic rubber, cyanate resin, and polycarbodifluoride are preferred. Imine resins are more preferably phenoxy resins, polyimide resins, urethane resins and acrylic rubbers, and particularly preferably phenoxy resins, urethane resins and acrylic rubbers. These (d) components may be used alone or as a mixture or copolymer of two or more. However, the component (d) does not include a compound corresponding to the component (a) and a compound corresponding to the component (e).

(D) The weight average molecular weight of a component is 10,000 or more, for example, Preferably it is 20,000 or more, More preferably, it is 30,000 or more. According to such a component (d), the heat resistance and film formation property of a 1st adhesive agent can be improved more. The weight average molecular weight of the (d) component is preferably 200,000 or less, and more preferably 100,000 or less. According to such (d) component, the heat resistance of a 1st adhesive agent can be improved more. From these viewpoints, the weight average molecular weight of the component (d) may be 10,000 to 200,000, 20,000 to 100,000, or 30,000 to 100,000.

In addition, in this specification, a weight average molecular weight means the weight average molecular weight at the time of a polystyrene conversion measurement using a high-performance liquid chromatography (made by Shimadzu Corporation, trade name: C-R4A). . For the measurement, the following conditions can be used, for example. Detector: LV4000 Ultraviolet (UV) Detector (manufactured by Hitachi, Ltd., trade name) Pump: L6000 Pump (Pump) (manufactured by Hitachi, Inc., trade name) Tube: Gilpa ( Gelpack) GL-S300MDT-5 (2 in total) (made by Hitachi Chemical Co., Ltd., trade name) Eluent: tetrahydrofuran (THF) / dimethyl formamide (DMF) = 1/1 ( Volume ratio) + LiBr (0.03 mol / L) + H3PO4 (0.06 mol / L) Flow rate: 1 mL / min

When an adhesive comprising a first component (d), the content of C (a) with respect to _a component C content of the component (d) ratio _d of C _a / C _d (mass ratio) is preferably 0.01 to 5, more preferably It is 0.05 to 3, and more preferably 0.1 to 2. When the ratio C _a / C _{d is} set to 0.01 or more, better hardenability and adhesive force can be obtained, and when the ratio C _a / C _{d is} set to 5 or less, more favorable film formability can be obtained.

[Component (e): Filler] The first adhesive contains a filler (component (e)) as necessary. The component (e) can control the viscosity of the first adhesive, the physical properties of the cured product of the first adhesive, and the like. Specifically, according to the component (e), for example, it is possible to suppress generation of voids during connection, reduce the moisture absorption rate of the cured product of the first adhesive, and the like.

Examples of the component (e) include inorganic fillers (inorganic particles) and organic fillers (organic particles). Examples of the inorganic filler include insulating inorganic fillers such as glass, silicon dioxide, aluminum oxide, titanium oxide, mica, and boron nitride. Among them, it is preferably selected from the group consisting of silicon dioxide, aluminum oxide, titanium oxide, and boron nitride. At least one of the groups is more preferably at least one selected from the group consisting of silicon dioxide, aluminum oxide, and boron nitride. The insulating inorganic filler may be a whisker. Examples of the whiskers include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, and boron nitride. Examples of the organic filler include a resin filler (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, so they are suitable for improving reflow resistance, and because they can impart flexibility, they are also effective in improving film formability.

From the viewpoint that it is easy to adjust the elastic modulus to a desired range, and that the occurrence of voids can be reduced more while suppressing warpage, and further excellent connection reliability can be obtained, the component (e) The total mass is used as a reference, and the content of the inorganic filler may be 50% by mass or more, 70% by mass or more, or 80% by mass or more. The content of the inorganic filler may be 100% by mass or less or 90% by mass.

From the viewpoint of more excellent insulation reliability, the (e) component is preferably insulating (as an insulating filler). The first adhesive is preferably a conductive metal filler (metal particle) that does not contain a silver filler or a solder filler, and a conductive inorganic filler such as carbon black.

From the viewpoint that it is easy to adjust the elastic modulus to a desired range, and that the occurrence of voids can be reduced more while suppressing warpage, and further excellent connection reliability can be obtained, the component (e) The total mass is used as a reference, and the content of the insulating filler may be 50% by mass or more, 70% by mass or more, or 90% by mass or more. (E) A component may contain substantially only an insulating filler. That is, the component (e) may not substantially contain a conductive filler. The "substantially free" means that the content of the conductive filler in the component (e) is less than 0.5% by mass based on the total mass of the component (e).

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

In terms of ease of surface treatment, the surface treatment is preferably a silane treatment using a silane compound such as an epoxy silane type, an amino silane type, or an acrylic silane type. From the viewpoint of excellent dispersibility, fluidity, and adhesion, the surface treatment agent is preferably selected from the group consisting of a glycidyl-based compound, a phenylamino-based compound, and a (meth) acrylic-based compound. At least one of the group. From the viewpoint of excellent storage stability, the surface treatment agent is preferably at least one selected from the group consisting of a phenyl-based compound and a (meth) acrylic-based compound.

The average particle diameter of the component (e) is preferably 1.5 μm or less from the viewpoint of preventing chipping during chip bonding, and more preferably 1.0 μm or less from the viewpoint of excellent visibility (transparency). .

From the viewpoint of suppressing a decrease in heat release property, and a viewpoint of easily suppressing generation of pores and an increase in moisture absorption rate, the content of the (e) component is preferably 15% by mass or more based on the total mass of the first adhesive. , More preferably 20% by mass or more, and even more preferably 40% by mass or more. From the viewpoints that it is easy to suppress an increase in viscosity and a decrease in the fluidity of the first adhesive, and it is easy to suppress a decrease in connection reliability due to a trapping of the filler to the connection portion, based on the total mass of the first adhesive The content of the (e) component is preferably 90% by mass or less, and more preferably 80% by mass or less. From these viewpoints, based on the total mass of the first adhesive, the content of the (e) component is preferably 15% to 90% by mass, more preferably 20% to 80% by mass, and even more preferably 40% to 80% by mass.

[Other components] In the first adhesive, additives such as an antioxidant, a silane coupling agent, a titanium coupling agent, a leveling agent, and an ion trapping agent may be blended. These can be used individually by 1 type or in combination of 2 or more types. These blending amounts may be appropriately adjusted so that the effect of each additive is exhibited.

From the viewpoint of reliability, the minimum melt viscosity of the first adhesive is preferably 1,000 Pa ･ s or more, more preferably 1500 Pa ･ s or more, and even more preferably 2000 Pa ･ s or more. If the minimum melt viscosity is 1000 Pa ･ s or more, the thermal expansion of the pores involved during encapsulation is suppressed, and the possibility of peeling during long-term use (for example, reliability test) is reduced. On the other hand, in the case of solder connection, the first layer is sufficiently eliminated, and the jamming of the resin is reduced, so that the electrical connection reliability is excellent. The minimum melt viscosity of the first adhesive is preferably 10,000 Pa ･ s or less. It is more preferably 5000 Pa ･ s or less, and still more preferably 4000 Pa ･ s or less. From these viewpoints, the minimum melt viscosity of the first adhesive is preferably 1,000 Pa ･ s to 10,000 Pa ･ s, more preferably 1500 Pa ･ s to 5000 Pa ･ s, and even more preferably 2000 Pa ･ s to 4000 Pa ･ s. The melt viscosity can be measured using a rotary rheometer (for example, ARES-G2 manufactured by TA Instruments). The melt viscosity is a melt viscosity measured under the following conditions. Measurement conditions Heating rate: 10 ℃ / min Frequency: 10 Hz Temperature range: 30 ℃ ～ 150 ℃

(Second Adhesive) The second adhesive does not substantially contain a flux compound. The "substantially free" 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.

From the viewpoint of remarkably obtaining the effect of the present invention, the curing reaction rate after the second adhesive is held at 200 ° C. for 5 seconds is preferably 80% or more. Examples of such a second adhesive include a radical curing adhesive. The reason why the effect of the present invention is remarkably obtained by such an adhesive is not clear, but the present inventors and others have speculated as follows.

That is, in a conventional film-like adhesive containing a flux compound, since a flux component inactivates radicals, a radical curing system cannot be applied, and in many cases, a cationic curing system using an epoxy group or the like is applied. In this hardening system (reaction system), since hardening is performed by a nucleophilic addition reaction, the hardening speed is slow, and pores may be generated after compression bonding. In the conventional film-like adhesive, it is presumed that a defective condition (for example, peeling of a semiconductor material at a reflow temperature around 260 ° C., or poor connection at a connection portion, etc.) occurred due to voids during the packaging. On the other hand, since the said 2nd adhesive agent does not contain a flux compound substantially, a hardening system can be set as a radical hardening system, and sufficient hardening speed can be obtained. Therefore, it is presumed that the use of the second adhesive in the second layer makes it difficult to generate pores even when the pressure bonding is performed at a high temperature for a short period of time, and the effect of the present invention becomes remarkable. In addition, in this embodiment, since a sufficient hardening speed can be obtained, even when solder is used in the connection portion, for example, the film-shaped adhesive can be hardened in a temperature range lower than the melting temperature of the solder. Therefore, it is possible to sufficiently suppress the occurrence of the solder scattering and flow, and the occurrence of connection failure.

Hereinafter, the second adhesive contains a radical polymerizable compound (hereinafter, referred to as "(A) component" as appropriate), a thermal radical generator (hereinafter, referred to as "(B) component" as appropriate), and if necessary An embodiment of a polymer component (hereinafter, referred to as "(C) component" as appropriate) and a filler (hereinafter, referred to as "(D) component" as appropriate) will be described.

[(A) Component: Radical Polymerizable Compound] The (A) component is a compound that can undergo a radical polymerization reaction with generation of radicals such as heat, light, radiation, and electrochemical action. Examples of the (A) component include a (meth) acrylic compound and a vinyl compound. From the viewpoint of excellent durability, electrical insulation, and heat resistance, the (A) component is preferably a (meth) acrylic compound. The (meth) acrylic compound is not particularly limited as long as it is a compound having one or more (meth) acrylic groups ((meth) acrylfluorenyl groups) in the molecule. For example, it can be used: bisphenol A type, bisphenol F type, naphthalene type, phenol novolac type, cresol novolac type, phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, fluorene type, adamantane type or heterotrimer (Meth) acrylic compounds of cyanic type skeleton; various polyfunctional (meth) acrylic compounds (except for (meth) acrylic compounds containing the skeleton), and the like. Examples of the polyfunctional (meth) acrylic compound include pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, trimethylolpropane di (meth) acrylate, and the like. (A) A component can be used individually by 1 type or in combination of 2 or more types.

From the viewpoint of excellent heat resistance and the viewpoint of suppressing generation of pores, the component (A) preferably has a bisphenol A type skeleton, a bisphenol F type skeleton, a naphthalene type skeleton, a fluorene type skeleton, an adamantane type skeleton, or The isotricyanic acid type skeleton preferably has a fluorene type skeleton. From the viewpoint that the generation of pores can be further suppressed, the (A) component is more preferably a (meth) acrylate having any of the above-mentioned skeletons.

The component (A) is preferably solid at room temperature (25 ° C). In the case of a solid, pores are less likely to be generated than in a liquid state, and the second adhesive before hardening (B-stage) has a small tack and is excellent in operability. Examples of the (A) component that is solid at room temperature (25 ° C) include a (meth) acrylate having a bisphenol A-type skeleton, a fluorene-type skeleton, an adamantane-type skeleton, or an isotricyanic acid-type skeleton. Wait.

The number of functional groups of the (meth) acrylic group in the component (A) is preferably 3 or less. When there are many functional groups, the hardened network expands rapidly, and unreacted groups may remain. On the other hand, if the number of functional groups is 3 or less, the number of functional groups does not become excessive, and curing in a short period of time is easily performed sufficiently, so that it is easy to suppress a reduction in the curing reaction rate.

The molecular weight of the component (A) is preferably less than 2000, and more preferably 1,000 or less. The smaller the molecular weight of the component (A), the easier the reaction proceeds, and the higher the curing reaction rate.

From the viewpoint of reducing the number of hardening components and easily controlling the flow of the resin after hardening, the content of the (A) component is preferably 10% by mass or more, more preferably 15% by mass based on the total mass of the second adhesive. %the above. From the viewpoint of suppressing the hardened material from becoming too hard and easily suppressing the warpage of the package from increasing, based on the total mass of the second adhesive, the content of the (A) component is preferably 50% by mass or less, and more preferably 40%. Mass% or less. From these viewpoints, based on the total mass of the second adhesive, the content of the component (A) is preferably 10% by mass to 50% by mass, and more preferably 15% by mass to 40% by mass.

From the viewpoint of suppressing a decrease in hardenability and easily suppressing a decrease in adhesion, the content of the component (A) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and more preferably 1 part by mass of the (C) component. It is 0.1 mass part or more. From a viewpoint of being easy to suppress the fall of a film formation property, content of (A) component is 10 mass parts or less with respect to 1 mass part of (C) component, More preferably, it is 5 mass parts or less. From these viewpoints, the content of the component (A) is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 1 part by mass of the (C) component. Part by mass to 5 parts by mass.

[Component (B): Thermal radical generator] The component (B) is not particularly limited as long as it functions as a curing agent of component (A). From the viewpoint of excellent workability, thermal radicals are preferred. Generating agent.

Examples of the thermal radical generator include an azo compound and a peroxide (such as an organic peroxide). The thermal radical generator is preferably a peroxide, and more preferably an organic peroxide. In this case, a radical reaction does not proceed in the step of drying the solvent when forming a film form, and the handleability and storage stability are excellent. Therefore, when a peroxide is used as a thermal radical generator, it is easy to obtain further excellent connection reliability. Examples of the organic peroxide include ketone peroxide, ketal peroxide, hydroperoxide, dialkyl peroxide, difluorenyl peroxide, peroxydicarbonate, and peroxyester. From the viewpoint of excellent storage stability, the organic peroxide is preferably at least one selected from the group consisting of a hydroperoxide, a dialkyl peroxide, and a peroxide ester. Furthermore, as the organic peroxide, from the viewpoint of excellent heat resistance, it is preferably at least one selected from the group consisting of a hydroperoxide and a dialkyl peroxide. Examples of the dialkyl peroxide include dicumyl peroxide, di-third butyl peroxide, and the like.

From a viewpoint of being easy to fully harden, content of (B) component is 0.5 mass part or more with respect to 100 mass parts of (A) component, More preferably, it is 1 mass part or more. The content of the component (B) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, based on 100 parts by mass of the component (A). When the upper limit value of the content of the component (B) is within the above range, hardening proceeds rapidly and the number of reaction points is suppressed, whereby the molecular chain is shortened and the unreacted group remains are suppressed. Therefore, if the upper limit value of the content of the (B) component is within the above range, it is easy to suppress a decrease in reliability. From these viewpoints, the content of the component (B) 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 component (A).

[(C) component: Polymer component] The second adhesive may further contain a polymer component. Examples of the component (C) include epoxy resin, phenoxy resin, polyimide resin, polyimide resin, polycarbodiimide resin, cyanate resin, (meth) acrylic resin, and polyester resin. , Polyethylene resin, polyether 碸 resin, polyether 醯 imine resin, polyvinyl acetal resin, urethane resin, acrylic rubber, etc. Among them, from the viewpoint of excellent heat resistance and film formation, It is preferably selected from the group consisting of epoxy resin, phenoxy resin, polyimide resin, (meth) acrylic resin, urethane resin, acrylic rubber, cyanate resin, and polycarbodiimide resin. At least one selected from the group consisting of epoxy resin, phenoxy resin, polyimide resin, (meth) acrylic resin, urethane resin, and acrylic rubber. At least one of. (C) A component may be used individually by 1 type, and may be used as a mixture or copolymer of 2 or more types. However, the component (C) does not include a compound corresponding to the component (A) and a compound corresponding to the (D) component.

From the viewpoint of excellent adhesion of the film-like adhesive for semiconductors to a substrate or a wafer, the glass transition temperature (Tg) of the component (C) is preferably 120 ° C or lower, more preferably 100 ° C or lower, and even more preferably Below 85 ° C. With these ranges, unevenness such as bumps formed on a semiconductor wafer, electrodes or wiring patterns formed on a substrate can be easily buried with a film-like adhesive for semiconductors (easy to suppress the onset of a curing reaction). , It is easy to suppress the situation where bubbles remain and pores are generated. The Tg is a differential scanning thermal analysis (DSC) (manufactured by Perkin Elmer Japan Co., Ltd., trade name: DSC-7) in a sample size of 10 mg. , Heating rate: 10 ° C / min, Measurement environment: Tg when measured under the condition of air.

The weight-average molecular weight of the component (C) is preferably 10,000 or more in terms of polystyrene conversion, and in order to exhibit good film formability alone, more preferably 30,000 or more, still more preferably 40,000 or more, particularly preferably 50,000 or more . When the weight average molecular weight is 10,000 or more, it is easy to suppress a decrease in film formability.

[(D) Component: Filler] The second adhesive may further contain a filler in order to control the viscosity or physical properties of the cured product, and to further suppress the occurrence of pores or the moisture absorption rate when the semiconductor wafer and the substrate or the semiconductor wafer are connected to each other. . As the component (D), the same fillers as those listed as the component (e) in the first adhesive can be used. Examples of preferred fillers are the same.

From the viewpoint of suppressing a decrease in heat release property, and of easily suppressing the generation of pores and increasing the moisture absorption rate, the content of the (D) component is preferably 15 mass% or more based on the total mass of the second adhesive. , More preferably 20% by mass or more, and even more preferably 40% by mass or more. From the viewpoints that it is easy to suppress an increase in viscosity and a decrease in the fluidity of the second adhesive, and to cause a trapping of the filler to the connection portion, and it is easy to suppress a decrease in connection reliability, based on the total mass of the second adhesive The content of (D) component is preferably 90% by mass or less, and more preferably 80% by mass or less. From these viewpoints, based on the total mass of the second adhesive, the content of the (D) component is preferably 15% to 90% by mass, more preferably 20% to 80% by mass, and even more preferably 40% to 80% by mass.

The minimum melt viscosity of the second adhesive is not particularly limited, and may be a value higher than the minimum melt viscosity of the first adhesive, or a value lower than the minimum melt viscosity of the first adhesive. The minimum melt viscosity of the second adhesive may also be within a preferred range of the minimum melt viscosity of the first adhesive (for example, 1000 Pa ･ s to 10,000 Pa ･ s). The minimum melt viscosity of the second adhesive can be measured by the same method as the minimum melt viscosity of the first adhesive.

[Other Components] Polymerizable compounds (for example, cationically polymerizable compounds and anionic polymerizable compounds) other than radical polymerizable compounds may be blended in the second adhesive. In addition, other components similar to those of the first adhesive may be blended in the second adhesive. These can be used individually by 1 type or in combination of 2 or more types. These blending amounts may be appropriately adjusted so that the effect of each additive is exhibited.

The curing reaction rate after the second adhesive is held at 200 ° C. for 5 seconds is preferably 80% or more, and more preferably 90% or more. If the hardening reaction rate at 200 ° C (below the melting temperature of the solder) for 5 seconds is 80% or more, it is easy to prevent the solder from scattering and flowing at the time of the connection (above the melting temperature of the solder), thereby reducing the reliability of the connection. The hardening reaction rate can be obtained by putting 10 mg of a second adhesive (uncured layer without flux) in an aluminum pan, and then using DSC (Perkin Elmer Japan ) Co., Ltd., trade name: DSC-7 type) Measurement of calorific value. Specifically, 10 mg of the second adhesive (uncured layer containing no flux) was placed in an aluminum pan, and the measurement sample thus obtained was placed on a heating plate heated to 200 ° C. The measurement sample was removed from the hot plate after 5 seconds. DSC was used to measure the heat-treated measurement sample and the untreated measurement sample. Based on the obtained calorific value, the curing reaction rate was calculated using the following formula. Hardening reaction rate (%) = (1- [calorific value of the measured sample after heat treatment] / [uncalorific value of the untreated measurement sample]) × 100

When the second adhesive contains an anionic polymerizable epoxy resin (particularly, an epoxy resin having a weight average molecular weight of 10,000 or more), it may be difficult to adjust the curing reaction rate to 80% or more. The content of the epoxy resin is preferably 20 parts by mass or less based on 80 parts by mass of the component (A), and more preferably does not contain an epoxy resin.

The second layer (layer without flux) containing the second adhesive can be crimped at a high temperature of 200 ° C or higher. In addition, in a flip-chip package in which a metal such as solder is melted to form a connection, more excellent hardenability is exhibited.

Regarding the thickness of the film-shaped adhesive for semiconductors of this embodiment, when the sum of the heights of the connection portions is set to x and the total thickness of the film-shaped adhesive for semiconductors is set to y, From the viewpoints of connectivity and filling of the adhesive, the relationship between x and y preferably satisfies 0.70x ≦ y ≦ 1.3x, and more preferably satisfies 0.80x ≦ y ≦ 1.2x. The total thickness of the film-shaped adhesive for semiconductors may be, for example, 10 μm to 100 μm, 10 μm to 80 μm, or 10 μm to 50 μm.

The thickness of the first layer may be, for example, 1 μm to 50 μm, 3 μm to 50 μm, 4 μm to 30 μm, or 5 μm to 20 μm.

The thickness of the second layer may be, for example, 7 μm to 50 μm, 8 μm to 45 μm, or 10 μm to 40 μm.

The ratio of the thickness of the second layer to the thickness of the first layer (the thickness of the second layer / the thickness of the first layer) may be, for example, 0.1 to 10.0, 0.5 to 6.0, or 1.0 to 4.0.

The film-shaped adhesive for semiconductors of this embodiment may further include layers other than the first layer and the second layer. For example, the semiconductor film-shaped adhesive of this embodiment may include a mixed layer including a first layer and a second layer. In addition, the film-shaped adhesive for semiconductors of this embodiment may include a base on a surface of the first layer opposite to the second layer and / or a surface of the second layer opposite to the first layer. Material film and / or protective film. In this case, an adhesive layer may be provided between the base film or the protective film and the first layer, and / or between the base film or the protective film and the second layer.

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

From the viewpoint of reliability, the minimum melt viscosity of the film-shaped adhesive is preferably 1,000 Pa ･ s or more, more preferably 1500 Pa ･ s or more, and even more preferably 2000 Pa ･ s or more. If the minimum melt viscosity is 1000 Pa ･ s or more, the thermal expansion of the pores involved during encapsulation is suppressed, and the possibility of peeling during long-term use (for example, reliability test) is reduced. On the other hand, in the case of solder connection, the first layer is sufficiently eliminated, and the jamming of the resin is reduced, so that the electrical connection reliability is excellent. The minimum melt viscosity of the film adhesive is preferably 10,000 Pa10000s or less. It is more preferably 5000 Pa ･ s or less, and still more preferably 4000 Pa ･ s or less. From these viewpoints, the minimum melt viscosity of the film-like adhesive is preferably 1,000 Pa ･ s to 10,000 Pa ･ s, more preferably 1500 Pa ･ s to 5000 Pa ･ s, and further preferably 2000 Pa ･ s to 4000 Pa ･ s. The minimum melt viscosity of the film-shaped adhesive can be measured by the same method as the minimum melt viscosity of the first adhesive.

<Manufacturing method of film-shaped adhesive for semiconductors> The film-shaped adhesive for semiconductors of this embodiment can be obtained, for example, by preparing a first film-shaped adhesive including a first layer and a second film including a second layer. The film-shaped adhesive includes a first film-shaped adhesive including a first layer and a second film-shaped adhesive including a second layer.

In the step of preparing the first film-shaped adhesive, for example, first, other components such as (a) component, (b) component and (c) component, and (d) component and (e) component added as necessary are added to In an organic solvent, a resin varnish (coating varnish) is prepared by dissolving or dispersing by stirring, mixing, kneading, and the like. Then, after the resin varnish is applied on the base film or the protective film subjected to the mold release treatment using a doctor blade coater, roll coater, applicator, etc., the organic solvent is reduced by heating, so that A first layer containing a first adhesive is formed on a base film or a protective film.

The organic solvent used in the preparation of the resin varnish is preferably one having properties capable of uniformly dissolving or dispersing each component, and examples thereof include dimethylformamide, dimethylacetamide, and N-methyl -2-Pyrrolidone, dimethyl sulfene, 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 may be used alone or in combination of two or more. Stirring, mixing, and kneading in the preparation of the resin varnish can be performed using, for example, a mixer, a mill, a three-roller, a ball mill, a bead mill, or a homogenizer.

The base film and the protective film are not particularly limited as long as they have heat resistance that can withstand heating conditions when the organic solvent is volatilized, and examples thereof include polyolefin films such as polypropylene films and polymethylpentene films; Polyester films such as polyethylene terephthalate film and polyethylene naphthalate film; polyimide film and polyetherimide film. The base film and the protective film are not limited to a single-layer film including these films, and may be a multilayer film including two or more materials. In addition, the base film and the protective film may include an adhesive layer on one surface thereof.

The drying conditions when the organic solvent is volatilized from the resin varnish applied to the substrate film are preferably conditions under which the organic solvent is sufficiently volatilized, and specifically, heating at 50 ° C to 200 ° C for 0.1 minute to 90 minutes is preferable . As long as it does not affect the porosity or viscosity adjustment after encapsulation, the organic solvent is preferably removed to 1.5% by mass or less relative to the total mass of the first film-like adhesive.

In the step of preparing the second film-shaped adhesive, other components such as (A) component and (B) component and (C) component added as necessary can be used in the same method as in the first layer. A second layer containing a second adhesive is formed on the base film or the protective film.

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

The film-shaped adhesive for semiconductors of this embodiment can also be obtained, for example, by forming one of the first layer or the second layer on a base film, and then on the obtained first layer or the second layer. Form the other of the first layer or the second layer. The first layer and the second layer can be formed by the same method as the method of forming the first layer and the second layer in the production of the film-like adhesive with a substrate.

The film-shaped adhesive for semiconductors of this embodiment can also be obtained, for example, by forming the first layer and the second layer substantially simultaneously on the substrate film. This method may be a method of forming the first layer and the second layer by applying the first adhesive and the second adhesive substantially simultaneously and drying them at once (simultaneous multi-layer coating method). A method in which a first adhesive is applied and a second adhesive is applied and then dried at once to form a first layer and a second layer (sequential multilayer coating method).

<Semiconductor Device> The semiconductor device of this embodiment will be described below using FIGS. 1 (a), 1 (b), 2 (a), and 2 (b). 1 (a) and 1 (b) are schematic cross-sectional views illustrating an embodiment of a semiconductor device according to the present invention. As shown in FIG. 1 (a), the semiconductor device 100 includes a semiconductor wafer 10 and a substrate (circuit wiring substrate) 20 facing each other, wirings 15 disposed on mutually facing surfaces of the semiconductor wafer 10 and the substrate 20, and a semiconductor Hardened product of connection bumps 30 where wafers 10 and wirings 15 of substrate 20 are connected to each other, and adhesives (first and second adhesives) filled in the gaps between semiconductor wafer 10 and substrate 20 without gaps的 密封 部 40。 The sealing portion 40. The semiconductor wafer 10 and the substrate 20 are connected via flip-chip bonding via the wiring 15 and the connection bump 30. The wiring 15 and the connection bumps 30 are sealed by a hardened material of the adhesive to block the external environment. The sealing portion 40 includes an upper portion 40 a containing a hardened material of the first adhesive and a lower portion 40 b containing a hardened material of the second adhesive.

As shown in FIG. 1 (b), the semiconductor device 200 includes a semiconductor wafer 10 and a substrate 20 facing each other, bumps 32 arranged on the mutually facing surfaces of the semiconductor wafer 10 and the substrate 20, and filling without gaps. The sealed portion 40 of the cured product of the adhesive (the first adhesive and the second adhesive) in the space between the semiconductor wafer 10 and the substrate 20. The semiconductor wafer 10 and the substrate 20 are connected to each other by the bumps 32 facing each other, and are connected via flip-chip bonding. The bumps 32 are sealed by the hardened material of the adhesive to block the external environment. The sealing portion 40 includes an upper portion 40 a containing a hardened material of the first adhesive and a lower portion 40 b containing a hardened material of the second adhesive.

2 (a) and 2 (b) are schematic cross-sectional views showing another embodiment of a semiconductor device according to the present invention. As shown in FIG. 2 (a), the semiconductor device 300 is the same as the semiconductor device 100 except that the two semiconductor wafers 10 are flip-chip connected via the wiring 15 and the connection bump 30. As shown in FIG. 2 (b), the semiconductor device 400 is the same as the semiconductor device 200 except that the two semiconductor wafers 10 are flip-chip connected by the bumps 32.

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

The substrate 20 is not particularly limited as long as it is a circuit substrate, and can be used as a main component including glass epoxy, polyimide, polyester, ceramic, epoxy, bis-cis- butadiene-imine triazine, and the like. A circuit board having wiring (wiring pattern) 15 formed by etching and removing an unnecessary portion of a metal film on the surface of an insulating substrate; and a circuit board having wiring 15 formed on the surface of the insulating substrate by metal plating or the like Circuit board; a circuit board or the like in which wiring 15 is formed by printing a conductive substance on the surface of the insulating substrate.

The connection portions such as the wiring 15 and the bump 32 include gold, silver, copper, solder (the main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc.), nickel, tin, Lead or the like may contain a plurality of metals as a main component.

Among these metals, gold, silver, and copper are preferred, and silver and copper are more preferred from the viewpoint of forming a package having excellent electrical and thermal conductivity of the connection portion. From the viewpoint of forming a package with reduced cost, silver, copper, and solder which are inexpensive materials are preferred, copper and solder are more preferred, and solder is more preferred. When an oxide film is formed on the surface of a metal at room temperature, productivity may decrease and cost may increase. Therefore, from the viewpoint of suppressing the formation of an oxide film, gold, silver, copper, and solder are preferred. , More preferably gold, silver, solder, and even more preferably gold, silver.

On the surfaces of the wiring 15 and the bumps 32, gold, silver, copper, and solder (main components are, for example, tin-silver, tin-lead, tin-bismuth, and tin- Copper, etc.), tin, nickel and other metal layers as main components. The metal layer may include only a single component or a plurality of components. In addition, the metal layer may have a structure in which a single layer or a plurality of metal layers are laminated.

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

As a method of stacking a plurality of semiconductor devices, as shown in FIG. 3, for example, a Through-Silicon Via (TSV) technology can be cited. 3 is a schematic cross-sectional view showing another embodiment of a semiconductor device according to the present invention, and is a semiconductor device using TSV technology. In the semiconductor device 500 shown in FIG. 3, the wiring 15 formed on the interposer 50 is connected to the wiring 15 of the semiconductor wafer 10 via the connection bump 30, thereby flip-chipping the semiconductor wafer 10 and the interposer 50. connection. The gap between the semiconductor wafer 10 and the interposer 50 is filled with a hardened material of the adhesive (the first adhesive and the second adhesive) without a gap, thereby constituting the sealing portion 40. A semiconductor wafer 10 is laminated on the surface of the semiconductor wafer 10 opposite to the interposer 50 through the wiring 15, the connection bump 30, and the sealing portion 40. The wirings 15 on the pattern surface of the front and back of the semiconductor wafer 10 are connected to each other by a through electrode 34 filled in a hole penetrating inside the semiconductor wafer 10. In addition, as a material of the through electrode 34, copper, aluminum, or the like can be used.

With this TSV technology, signals can also be obtained from the back of a semiconductor wafer that is not normally used. Furthermore, since the penetrating electrode 34 is vertically inserted in the semiconductor wafer 10, the distance between the opposing semiconductor wafers 10 and the distance between the semiconductor wafer 10 and the interposer 50 can be shortened to allow flexible connection. In such TSV technology, the film-like adhesive for semiconductors of this embodiment can be suitably used as a film-like adhesive for semiconductors between the opposing semiconductor wafers 10 and between the semiconductor wafers 10 and the interposer 50.

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

<Method for Manufacturing Semiconductor Device> A method for manufacturing a semiconductor device according to this embodiment will be described below using FIGS. 4 (a) to 4 (c). 4 (a) to 4 (c) are diagrams schematically showing an embodiment of a method for manufacturing a semiconductor device according to the present invention, and each step is shown in Figs. 4 (a), 4 (b), and 4 (c). ) Shows a cross section of a semiconductor device.

First, as shown in FIG. 4 (a), a solder resist 60 having an opening at a position for forming the connection bump 30 is formed on the substrate 20 having the wiring 15. This solder resist 60 is not necessarily provided. However, since the solder resist is provided on the substrate 20, the occurrence of bridging between the wirings 15 can be suppressed, thereby improving connection reliability and insulation reliability. The solder resist 60 can be formed using, for example, a commercially available ink for a solder resist for packaging. Specific examples of commercially available inks for packaging solder resists include SR series (manufactured by Hitachi Chemical Co., Ltd., trade name) and PSR4000-AUS series (manufactured by Sun Ink Manufacturing Co., Ltd., trade name).

Next, as shown in FIG. 4 (a), a connection bump 30 is formed at the opening of the solder resist 60. Then, as shown in FIG. 4 (b), the substrate 20 on which the connection bumps 30 and the solder resist 60 are formed is attached so that the surface on the second layer 41 b side including the second adhesive agent becomes the substrate 20 side. A film-shaped adhesive for semiconductors (hereinafter, referred to as a "film-shaped adhesive" as appropriate) 41 in this embodiment. The film-like adhesive 41 can be attached by heat pressing, roll lamination, vacuum lamination, or the like. The supply area and thickness of the film-like adhesive 41 are appropriately set according to the sizes of the semiconductor wafer 10 and the substrate 20, the height of the connection bumps 30, and the like. In addition, the film-shaped adhesive 41 may be adhered so that the surface on the first layer 41 a side including the first adhesive becomes the substrate 20 side.

After the film-like adhesive 41 is attached to the substrate 20 as described above, the wiring 15 of the semiconductor wafer 10 and the connection bump 30 are aligned using a connection device such as a flip-chip bonding machine. Next, the semiconductor wafer 10 and the substrate 20 are pressure-bonded while being heated at a temperature higher than the melting point of the connection bump 30, so that the semiconductor wafer 10 and the substrate 20 are connected as shown in FIG. 4 (c). The sealed portion 40 of the cured product of the film-shaped adhesive 41 seals and fills the gap between the semiconductor wafer 10 and the substrate 20. The semiconductor device 600 is obtained as described above.

The crimping time may be, for example, 5 seconds or less. In this embodiment, since the film-shaped adhesive 41 of this embodiment is used, a semiconductor device having excellent connection reliability can be obtained even if the crimping time is 5 seconds or less.

In the method for manufacturing a semiconductor device according to this embodiment, it is also possible to temporarily fix (positioned with a film-like adhesive for semiconductors) after alignment and heat treatment in a reflow furnace to make the connection bumps. 30 melts and connects the semiconductor wafer 10 and the substrate 20. Since it is not necessary to form a metal joint in the temporary fixing stage, compared with the method of performing crimping while heating, the crimping can be performed at a lower load, in a shorter time, and at a lower temperature, and productivity can be improved. Suppression of deterioration of the connection portion.

In addition, after the semiconductor wafer 10 and the substrate 20 are connected, heat treatment may be performed using an oven or the like, thereby further improving connection reliability and insulation reliability. The heating temperature is preferably a temperature at which the film-like adhesive is cured, and more preferably a temperature at which the film-shaped adhesive is completely cured. The heating temperature and heating time can be set appropriately.

In the method of manufacturing a semiconductor device according to this embodiment, the substrate 20 may be connected after the film-shaped adhesive 41 is attached to the semiconductor wafer 10.

From the viewpoint of improving productivity, the semiconductor wafer 10 can be obtained by supplying a film-like adhesive for semiconductors to a semiconductor wafer to which a plurality of semiconductor wafers 10 are connected and then singulating and singulating the wafer. A structure provided with a film-shaped adhesive for semiconductors. The film-like adhesive for semiconductors may be supplied, for example, by filling the wirings, bumps, and the like on the semiconductor wafer 10 by means of attachment methods such as heat pressing, roll lamination, and vacuum lamination. In this case, since the supply amount of the resin is fixed, productivity is improved, and generation of pores and reduction in crystallinity due to insufficient landfilling can be suppressed.

The connection load can be set in consideration of variations in the number and height of the connection bumps 30, and the amount of deformation of the wiring of the connection bumps 30 or the bumps receiving the connection portions due to pressure. Regarding the connection temperature, the temperature of the connection portion is preferably equal to or higher than the melting point of the connection bump 30, but may be any temperature that can form a metal bond of each connection portion (bump and wiring). When the connection bump 30 is a solder bump, it is preferably about 240 ° C or higher.

The connection time at the time of connection varies depending on the constituent metal of the connection portion, but from the viewpoint of improving productivity, the shorter the time, the better. When the connection bump 30 is a solder bump, the connection time is preferably 20 seconds or less, more preferably 10 seconds or less, and even more 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.

In the flip-chip connection portions of the various package structures, the film-shaped adhesive for semiconductors of this embodiment all exhibited excellent reflow resistance and connection reliability.

As mentioned above, although suitable embodiment of this invention was described, this invention is not limited to the said embodiment. [Example]

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples.

<Production of a single-layer film including a flux-containing layer> The compounds used in the production of a single-layer film including a flux-containing layer are shown below. (A) Epoxy resins • Multifunctional solid epoxy resins containing a triphenol methane skeleton (manufactured by Mitsubishi Chemical Corporation, trade name “jER1032H60”) • Bisphenol F-type liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation) , Trade name "jERYL983U") (b) Hardener, 2,4-diamino-6- [2'-methylimidazole- (1 ')]-ethyl-s-triazine isocyanuric acid addition Material (manufactured by Shikoku Chemical Industry Co., Ltd., trade name "2MAOK-PW") (c) flux · glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd., melting point about 98 ° C)-2-methylglutaric acid ( Manufactured by Sigma Aldrich, melting point is about 78 ° C.) 3-Methylglutaric acid (Tokyo Kasei Co., Ltd., melting point is about 87 ° C) (d) Polymer component. Phenoxy resin (new Manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., trade name "ZX1356-2", Tg: about 71 ° C, weight average molecular weight Mw: about 63000) ・ Phenoxy resin (manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., trade name " FX-293 ", Tg: about 160 ° C, weight average molecular weight Mw: about 40,000 (E) Fillers and silica fillers (manufactured by Admatechs Co., Ltd., trade name "SE2050", average particle size: 0.5 μm) • Epoxy silane surface treatment fillers (Admatechs Limited) Manufactured by the company, SE2050-SEJ, average particle size: 0.5 μm) ・ Methacrylic acid surface-treated nanometer silica filler (manufactured by Admatechs Co., Ltd., trade name "YA100C-MLE", average particle size: Approx. 100 nm) • Methacrylic acid-treated nano silica filler (Admatechs Co., Ltd., trade name “YA050C-MJE”, average particle size: about 50 nm) • Organic filler (resin filler, (Manufactured by Rohm and Haas Japan Co., Ltd., trade name "EXL-2655", core-shell type organic fine particles)

Epoxy resin, hardener, polymer component, flux, inorganic filler, and organic filler in the blending amount (unit: part by mass) shown in Table 1 are represented by NV values ([Dried coating composition mass] / [Before drying] The coating composition mass] × 100) is added to the organic solvent (methyl ethyl ketone) so that it becomes 60%. Then, add Φ 1.0 mm beads and Φ 2.0 mm beads of the same mass as the solid components (epoxy resin, hardener, flux, polymer component, inorganic filler, and organic filler), and use a bead mill (Japan Fritsch Japan Co., Ltd. Planetary Pulverizer P-7) Stir for 30 minutes. After stirring, the beads were removed by filtration to produce a coated varnish containing a first adhesive.

The obtained coating varnish was applied to a substrate film (made by Teijin DuPont Film Co., Ltd. under the trade name "Purex A54") using a small precision coating device (manufactured by Lianjing Seiki Co., Ltd.). In the above, a clean oven (manufactured by ESPEC) Co., Ltd. was used for drying (80 ° C / 10 min) to obtain the single-layer film (A-1) and the single-layer film (A- 2) The single-layer film (A-3), the single-layer film (A-4) and the single-layer film (A-5) are used as the first film. The thickness of the flux-containing layer in the single-layer film (A-1) to the single-layer film (A-5) was set to 20 μm.

[Table 1]

<Production of single-layer film including layer containing no flux> The compounds used for production of a single-layer film including a layer containing no flux are shown below.

(A) (meth) acrylic compounds · Acrylates with fluorene-type skeleton (Osaka Gas Chemical Co., Ltd., EA-0200, difunctional group) · Acrylates with bisphenol A-type skeleton (Shinakamura Chemical Industry Co., Ltd. Company, EA-1020) ・ Ethoxylated isotricyanuric acid triacrylate (Sin Nakamura Chemical Industry Co., Ltd., A-9300)

(B) Thermal radical generator · Dicumyl peroxide (Nippon Oil Co., Ltd., Percumyl (registered trademark) D) ・ Di-tert-butyl peroxide (Nippon Oil Co., Ltd., Perbutyl (registered trademark) D) ・ 1,4-bis-((third butyl peroxide) diisopropyl) benzene (Nippon Oil Co., Ltd., Perbutyl (registered trademark) P )

(C) Polymer components and acrylic resins (Hitachi Kasei Co., Ltd., KH-CT-865, weight average molecular weight Mw: 100,000, Tg: 10 ° C) • Urethane resins (Diesen Covestro Polymers ( DIC Covestro Polymer) Co., Ltd., Pandex T-8175N, Tg: about -23 ° C)

(D) Filler The same filler as the filler ((e) component) used in the production of the single-layer film including the flux-containing layer is used.

The (meth) acrylic compound, polymer component, inorganic filler, and organic filler in the compounded amount (unit: mass part) shown in Table 2 were added to the organic solvent (methyl ethyl ketone) so that the NV value became 60%. in. Then, Φ 1.0 mm beads and Φ 2.0 mm beads having the same mass as the solid component ((meth) acrylic compound, polymer component, inorganic filler and organic filler) were added, and the beads were milled (Fritz, Japan) (Fritsch Japan) Co., Ltd. Planetary Pulverizer P-7) Stir for 30 minutes. After stirring, the beads were removed by filtration. Next, a thermal radical generator is added to the obtained mixture, and the mixture is stirred and mixed to prepare a coated varnish including a second adhesive.

The obtained coating varnish was applied to a substrate film (manufactured by Teijin Dupont Membrane Co., Ltd. under the trade name "Purex A54") using a small precision coating device (Lianjing Seiki), and cleaned using Oven (manufactured by ESPEC Co., Ltd.) and dried (80 ° C / 10 min) to obtain the single-layer film (B-1), single-layer film (B-2), single-layer film shown in Table 2 A layer film (B-3), a single layer film (B-4), a single layer film (B-5), a single layer film (B-6), and a single layer film (B-7) are used as the second film. The thickness of the flux-free layer in the single-layer film (B-1) to the single-layer film (B-7) was set to 20 μm.

[Table 2]

<Production of a double-layer film> (Examples 1 to 10 and Comparative Examples 1 to 12) Two of the single-layer films (the first film and the second film) produced as described above were heated at 50 ° C. Lamination was carried out underneath to produce a film-shaped adhesive with a total thickness of 40 μm. The combinations of the single-layer films are shown in Tables 3 and 4. The base film on the single-layer film side including the flux-containing layer was peeled off, and the base film on which the base film was peeled off was laminated with a base film (6331-00) provided with an adhesive layer on the side of the flux-containing layer. , Manufactured by Hitachi Maxell Co., Ltd.). In Comparative Examples 1 to 5, only one of the substrate films was peeled off, and the substrate film provided with an adhesive layer (6331-00, Hitachi Mansion) was laminated on the surface from which the substrate film was peeled. (Maxell) Co., Ltd.).

<Evaluation 1> (Measurement of Minimum Melt Viscosity) The first adhesive, the second adhesive, and the film-shaped adhesive (measured using a rotary rheometer (TA Instruments), trade name: ARES-G2) were measured ( The melt viscosity of a layer containing a flux-containing layer and a flux-free layer. A sample for evaluating the melt viscosity of the film-shaped adhesive was prepared in the following procedure. First, two of the single-layer films (the first film and the second film) produced as described above were laminated at 50 ° C. to produce a double-layer film having a total thickness of 40 μm. The combinations of the single-layer films are shown in Tables 3 and 4. This double-layer film was cut, and the cut double-layer films were laminated on each other, thereby producing a four-layer film (laminated film) with a total thickness of 80 μm. In the same procedure, cutting of the laminated film and lamination of the cut laminated film were repeated to prepare an evaluation sample having a total thickness of 400 μm. Using the evaluation sample, the melt viscosity was measured under the following measurement conditions. [Measurement conditions] Heating rate: 10 ℃ / min Frequency: 10 Hz Temperature range: 30 ℃ ～ 150 ℃

The minimum melt viscosity of the first adhesive is 2000 Pa ･ s to 4000 Pa ･ s (measured at 130 ° C), and the minimum melt viscosity of the second adhesive is 1000 Pa ･ s to 3000 Pa ･ s (120 ° C (Measured value), and the minimum melt viscosity of the film adhesive is 1500 Pa1500s to 3500 Pa ･ s (measured value at 130 ° C).

<Evaluation 2> The film-like adhesives obtained in the examples and comparative examples and the semiconductor devices produced using the film-like adhesives were subjected to initial connectivity evaluation, porosity evaluation, and solder wettability evaluation by the methods shown below. , Exudation measurement, and insulation reliability evaluation. The results are shown in Tables 3 and 4.

(Evaluation of initial connectivity) The film-like adhesive produced in the examples or comparative examples was cut to a predetermined size (8 mm in height × 8 mm in width × 40 μm in thickness), and the base film without the adhesive layer was peeled off . Laminated on a semiconductor wafer with solder bumps (wafer size: 7.3 mm x 7.3 mm x thickness 0.15 mm, bump height: Approximately 40 μm based on the total height of the copper pillar and the height of the solder, bumps Number: 328). The base film provided with the adhesive layer was peeled off, and the laminated wafer was packaged with the flux-containing layer facing downward using a flip-chip packaging device "FCB3" (manufactured by Panasonic Corporation, trade name). On a glass epoxy substrate with copper wiring (thickness of glass epoxy substrate: 420 μm, thickness of copper wiring: 9 μm) (package condition: crimping temperature 350 ° C, crimping time 3 seconds, crimping pressure 0.5 MPa). Thereby, the semiconductor device A in which the said glass epoxy substrate and the semiconductor wafer with a solder bump were connected via the daisy chain was produced similarly to FIG.4 (a)-(c).

The connection resistance value of the obtained semiconductor device A was measured using a multimeter (manufactured by ADVANTEST Co., Ltd., trade name "R6871E") to evaluate the initial conduction after packaging. A case where the connection resistance value is 10.0 Ω or more and 12.5 Ω or less is evaluated as a connectivity "A" (good), and a case where the connection resistance value is greater than 12.5 Ω and is 13.5 Ω or less is evaluated as a connectivity "B" (bad), The case where the connection resistance value is greater than 13.5 Ω and less than 20 Ω is evaluated as the connectivity "C" (bad), the case where the connection resistance value is more than 20 Ω, the case where the connection resistance value is less than 10 Ω, and All cases where the resistance value was displayed were evaluated as connectivity "D" (defective).

(Porosity Evaluation) An ultrasonic image diagnostic apparatus (trade name "Insight-300", manufactured by Insight Co., Ltd.) was used to photograph an external view of the semiconductor device A produced by the method described above. Image, and an image of an adhesive layer (a layer containing a cured product of a film-like adhesive for semiconductors) introduced on a wafer using a scanner GT-9300UF (manufactured by Seiko Epson Co., Ltd., trade name) and used The image processing software Adobe Photoshop (registered trademark) recognizes the pores by tone correction and two gray scales, and calculates the proportion of the pores by using a histogram. The area of the adhesive portion on the wafer was set to 100%, a case where the porosity generation rate was 3% or less was evaluated as "AA" (good), and a case where the porosity generation rate was more than 3% and less than 5% was evaluated as "A" (good), the case where the porosity generation rate was more than 5% and 10% or less was evaluated as "B" (bad), and the case where the porosity generation rate was more than 10% was evaluated as "C" (bad).

(Evaluation of Solder Wetability) Regarding the semiconductor device A produced by the above method, the cross section of the connection portion was observed, and the case where the solder wetting on the upper surface of the Cu wiring was 100% to 50% was evaluated as "A "(Good), the case where solder wetting was 50% to 0% was evaluated as" B "(defective), and the case where solder scattering occurred was evaluated as" C "(defective).

(Measurement of Exudation Amount) Using a metal microscope (manufactured by Keyence Co., Ltd.), the semiconductor device A produced by the above method was observed from the upper surface of the semiconductor device A, and the semiconductor device A was measured from the periphery of the semiconductor wafer (four sides). ) Exuded amount of hardened material derived from the film-like adhesive (width of exuded portion). The measurement was performed for each side of the semiconductor device, and the average value of the four sides was calculated as the exudation amount.

(Insulation Reliability Test A [HAST Test: Highly Accelerated Storage Test]) The film-shaped adhesive (thickness: 40 μm) produced in the examples or comparative examples was attached to a comb-shaped electrode evaluation test Test Element Group (TEG) (manufactured by Hitachi Chemical Co., Ltd., wiring pitch: 50 μm), using a flip-chip package "FCB3" (manufactured by Panasonic Co., Ltd., trade name). Semiconductor wafer with solder bumps (wafer size: 7.3 mm in height x 7.3 mm in width x 0.15 mm in thickness, bump height: approx. 40 μm in total of the height of the copper pillar and the height of the solder, the number of bumps: 328) Package with the solder side facing down (packaging conditions: thermocompression bonding at a crimping temperature of 350 ° C, a crimping time of 3 seconds, and a crimping pressure of 0.5 MPa). Thereby, a semiconductor device B is obtained. The crimped semiconductor device B was cured in a clean oven (manufactured by ESPEC) at 175 ° C for two hours, and the cured sample was set in an accelerated life tester (Hirayama Manufacturing Co., Ltd.) Manufacture, trade name "PL-422R8", conditions: 130 ° C / 85% RH / 100 hours, 5 V applied), the insulation resistance was measured. A case where the insulation resistance after 100 hours was 10 ⁸ Ω or more was evaluated as “A”, a case where it was 10 ⁷ Ω or more and less than 10 ⁸ Ω was evaluated as “B”, and a case where the insulation resistance was less than 10 ⁷ Ω was evaluated as "C".

(Insulation Reliability Test B [HAST Test: Highly Accelerated Storage Test]) The film-shaped adhesive (thickness: 40 μm) produced in the examples or comparative examples was attached to a comb-shaped electrode to evaluate TEG (Hitachi Chemical Co., Ltd., wiring pitch: 50 μm), using a flip-chip package "FCB3" (manufactured by Panasonic Co., Ltd., trade name), a semiconductor wafer (wafer) with solder bumps from the top Dimensions: 7.3 mm vertical × 7.3 mm horizontal × 0.15 mm thick, bump height: the total of the height of the copper pillar and the height of the solder is about 40 μm, the number of bumps: 328) with the solder side facing down Encapsulated in the state (under the packaging conditions: the temperature of the crimp joint is 180 ° C, the crimping time is 3 seconds, and the thermocompression bonding is performed at a crimping pressure of 0.5 MPa (the gelation step of the adhesive), the temperature of the crimp joint is increased to 260 ° C, The thermocompression bonding was performed continuously at a pressure joint temperature of 260 ° C, a crimping time of 3 seconds, and a crimping pressure of 0.5 MPa). Thereby, a semiconductor device C is obtained. The crimped semiconductor device C was cured in a clean oven (manufactured by ESPEC) at 175 ° C for two hours, and the cured sample was set in an accelerated life tester (Hirayama Manufacturing Co., Ltd.) Manufacture, trade name "PL-422R8", conditions: 130 ° C / 85% RH / 100 hours, 5 V applied), the insulation resistance was measured. The case where the insulation resistance after 100 hours was 10 ⁸ Ω or more was evaluated as "A", the case where the insulation resistance was 10 ⁷ Ω or more and less than 10 ⁸ Ω was evaluated as "B", and the case where the insulation resistance was less than 10 ⁷ Ω was evaluated as "C".

[table 3]

[Table 4]

In the film-like adhesives for semiconductors of Examples 1 to 10, generation of voids was sufficiently suppressed, and solder wettability was good. In addition, it was confirmed that these film-like adhesives for semiconductors have a small amount of bleed out after encapsulation, and also have excellent insulation reliability (HAST resistance).

10‧‧‧Semiconductor wafer

15‧‧‧Wiring (connection section)

20‧‧‧ substrate (wiring circuit substrate)

30‧‧‧ connecting bump

32‧‧‧ bump (connection part)

34‧‧‧through electrode

40‧‧‧Sealing Department

40a‧‧‧upper

40b‧‧‧ lower part

41‧‧‧film adhesive for semiconductors (film adhesive)

41a‧‧‧Level 1

41b‧‧‧Layer 2

50‧‧‧ intermediary

60‧‧‧solder resist

100, 200, 300, 400, 500, 600‧‧‧ semiconductor devices

1 (a) and 1 (b) are schematic cross-sectional views illustrating an embodiment of a semiconductor device according to the present invention. 2 (a) and 2 (b) are schematic cross-sectional views showing another embodiment of a semiconductor device according to the present invention. FIG. 3 is a schematic cross-sectional view showing another embodiment of a semiconductor device according to the present invention. 4 (a) to 4 (c) are cross-sectional views schematically showing steps in an embodiment of a method for manufacturing a semiconductor device according to the present invention.

Claims (14)

A film-like adhesive for semiconductors, comprising: a first layer including a first thermosetting adhesive, the first thermosetting adhesive including a flux compound; and a second layer provided on the first layer and including a second The second layer of the thermosetting adhesive, the second thermosetting adhesive contains substantially no flux compound. The film-like adhesive for semiconductors according to item 1 of the scope of patent application, wherein the second thermosetting adhesive is held at 200 ° C. for 5 seconds and has a curing reaction rate of 80% or more. The film-shaped adhesive for semiconductors according to claim 1 or claim 2, wherein the second thermosetting adhesive contains a radical polymerizable compound and a thermal radical generator. The film-like adhesive for semiconductors according to item 3 of the scope of the patent application, wherein the thermal radical generator is a peroxide. The film-shaped adhesive for semiconductors according to claim 3 or 4, wherein the radical polymerizable compound is a (meth) acrylic compound. The film-shaped adhesive for semiconductors according to item 5 of the scope of patent application, wherein the (meth) acrylic compound has a fluorene-type skeleton. The film-shaped adhesive for semiconductors according to any one of claims 1 to 6, wherein the flux compound has a carboxyl group. The film-shaped adhesive for semiconductors according to any one of claims 1 to 7, wherein the flux compound has two or more carboxyl groups. The film-shaped adhesive for semiconductors according to any one of claims 1 to 8 in the scope of the patent application, wherein the flux compound is a compound represented by the following formula (2); In formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron donating group, and n represents an integer of 0 or 1 or more. The film-like adhesive for semiconductors according to any one of claims 1 to 9 in the scope of the patent application, wherein the melting point of the flux compound is 150 ° C. or lower. The film-shaped adhesive for semiconductors according to any one of claims 1 to 10 in the scope of patent application, wherein the first thermosetting adhesive contains a curing agent. The film-shaped adhesive for semiconductors according to item 11 of the scope of application, wherein the hardener is an imidazole-based hardener. A method for manufacturing a semiconductor device is a method for manufacturing a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a method of manufacturing a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other. The manufacturing method of the device includes the step of sealing at least a part of the connection portion using the film-shaped adhesive for semiconductors according to any one of claims 1 to 12 of the scope of patent application. A semiconductor device is a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other, at least a part of the connection portion is The hardened product of the film-shaped adhesive for semiconductors as described in any one of the scope of claims 1 to 12 of the scope of application for a patent.