TWI748105B - Film adhesive for semiconductor, method for manufacturing semiconductor device, and semiconductor device - Google Patents

Abstract

The film adhesive for semiconductors of the present invention includes: a first layer containing a first thermosetting adhesive, the first thermosetting adhesive containing a flux compound; and a first layer provided on the first layer and containing a second heat In the second layer of the curable adhesive, the second thermosetting adhesive does not substantially contain a flux compound.

Description

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

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

In the past, 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 high-function, high-integration, and high-speed semiconductor devices, conductive bumps called bumps are formed on semiconductor wafers or substrates to directly connect semiconductor wafers and substrates. The flip chip connection method (FC (flip chip) connection method) is being promoted.

For example, regarding the connection between the semiconductor chip and the substrate, the ball grid array (Ball Grid Array, BGA), chip size package (Chip Size Package, CSP), etc. are popularly used in the chip on board (Chip On Board, COB) type of connection The method is also equivalent to the FC connection method. In addition, the FC connection method is also widely used in a chip on chip (COC) type connection method in which connecting portions (for example, bumps and wiring) are formed on a semiconductor chip to connect the semiconductor chips.

In addition, in a package that strongly requires further miniaturization, thinning, and high-functioning, the above-mentioned connection method is used to laminate and multi-stage chips to form a chip stack type package and a package on package (Package On Package). , POP), Through-Silicon Via (TSV), etc. have also begun to spread widely. This multi-layer and multi-segment technology arranges semiconductor wafers in three dimensions, so the package can be reduced compared to the two-dimensional arrangement method. In addition, it is also effective in improving semiconductor performance, reducing noise, reducing package area, and saving power, and is therefore attracting attention as the next-generation semiconductor wiring technology.

In addition, in the connection between the connection parts, in terms of ensuring sufficient connection reliability (for example, insulation reliability), metal bonding has been used. As the main metal used in the connection portion (for example, bumps and wiring), there are solder, tin, gold, silver, copper, nickel, etc., and conductive materials including many of these are also used. The metal used in the connection portion is oxidized on the surface to form an oxide film, and impurities such as oxides adhere to the surface, so 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 decrease, which may impair the advantages of using the connection method.

In addition, as a method of suppressing the generation of these impurities, there is a method known in Organic Solderbility Preservatives (OSP) treatment, etc., to coat the connection part with an anti-oxidation film, but the anti-oxidation The film sometimes causes the decrease in solder wettability and connectivity during the connection process.

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

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

In addition, in flip-chip packaging, in recent years, there has been a further development towards high functionality and high integration. With the increase in functionality and integration, the spacing 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 shorten the crimping time during assembly of the flip chip package. In the case of shortening the crimping time, if the film-like adhesive for semiconductors is not sufficiently cured during crimping, the connection portion cannot be sufficiently protected, and connection failure may occur when the pressure of crimping is released. Furthermore, when solder is used in the connection part, if the film-like adhesive for semiconductors is not sufficiently cured in a temperature range lower than the melting temperature of the solder during crimping, solder will be generated when the temperature during crimping reaches the melting temperature of the solder. Dispersion and flow of the air lead to poor connection. On the other hand, when the film-like adhesive for semiconductors is cured before the connection portions come into contact with each other by pressure bonding, the adhesive is in a state where the adhesive intervenes between the connection portions, and connection failure occurs.

Therefore, an object of the present invention is to provide a film-like adhesive for semiconductors that can obtain excellent connection reliability even when the pressure bonding time is short. In addition, an object of the present invention is to provide a semiconductor device using such a film-like adhesive for semiconductors and a method of manufacturing the same.

The film adhesive for semiconductors of the present invention includes: a first layer containing a first thermosetting adhesive, the first thermosetting adhesive containing a flux compound; and a first layer provided on the first layer and containing a second heat In the second layer of the curable adhesive, the second thermosetting adhesive does not substantially contain a flux compound.

According to the film-like adhesive for semiconductors of the present invention, the second layer is less susceptible to the influence of the flux compound. Therefore, the second layer can exhibit the characteristics of rapid and sufficient hardening after the connecting portions come into contact with each other. In addition, with regard to the film-like adhesive as described in Patent Document 2, the thermoplastic resin is likely to soften at high temperatures such as pressure bonding and cause problems such as peeling, which may cause problems from the viewpoint of reliability. On the one hand, such a problem does not easily occur in the film-like adhesive for semiconductors of the present invention. For these reasons, according to the film-like adhesive for semiconductors of the present invention, even when crimping is performed at a high temperature in a short time, excellent connection reliability (for example, insulation reliability) can be obtained. In addition, according to the film-like adhesive for semiconductors of the present invention, the crimping time can be shortened, so productivity can be improved. In addition, according to the film-like adhesive for semiconductors of the present invention, the flip chip package can be easily enhanced in functionality and integration.

In addition, conventional adhesives for semiconductors (for example, the film-like adhesive described in Patent Document 1), when the pressure bonding time is short, will undergo high temperature pressure bonding in a state where the semiconductor adhesive is not sufficiently cured. Sometimes voids are generated, and sometimes peeling occurs inside the package starting from the voids. If the peeling inside the package becomes larger, stress acts on the connection portion and cracks are generated. Therefore, the peeling inside the package may cause poor connection of the package. In contrast, the film-like adhesive for semiconductors according to the present invention can be sufficiently cured in a short period of time, so that 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 a flux compound hardens quickly. Therefore, even if microvoids are generated, the expansion of the voids is suppressed, and it is difficult to produce visible levels. The size of the pores. These conditions can be regarded as one of the reasons why the film-like adhesive of the present invention obtains excellent bonding reliability.

In addition, in the case of fabricating flip-chip packages using conventional film-like adhesives, the adhesive may ooze from the periphery of the wafer because the adhesive does not harden in a short period of time. Such exudation of the adhesive will hinder the mounting of adjacent chips, resulting in a reduction in the number of packages that can be mounted per wafer. That is, if the adhesive seeps from the periphery of the wafer, productivity will be reduced. In addition, if the amount of bleed-out of the adhesive is excessive, the bleeded-out adhesive may spread to the mounted wafer, which may cause damage to the mounted wafer when another wafer is further mounted on the wafer. On the other hand, the film-like adhesive for semiconductors according to the present invention can be cured sufficiently in a short time, so that the occurrence of bleeding of the adhesive can be suppressed.

In addition, in recent years, as the metal of the connection portion, for the purpose of cost reduction, there is a tendency to use solder, copper, etc., instead of gold, which is not easily corroded. Furthermore, with regard to the surface treatment of wiring and bumps, for the purpose of cost reduction, there is a tendency to use solder, copper, etc., instead of gold, which is not easily corroded, and to perform treatments such as OSP (Organic Solderability Preservative) treatment. In flip-chip packages, in addition to narrower pitches and multi-pins, this type of cost reduction is also promoted. Therefore, there is a tendency to use metals that are prone to corrosion and lower insulation, and insulation reliability tends to be lowered. In contrast, according to the film-like 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 of the second thermosetting adhesive after being 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 in 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, the hardening speed is very excellent, so even when the pressure bonding is performed at a high temperature in a short time, voids are not easily generated, and more excellent connection reliability can be obtained.

The thermal radical generator is preferably peroxide. In this case, further superior operability and storage stability can be obtained, and therefore further superior connection reliability can be easily obtained.

The radically 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 sulphur-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.

[式（2）中，R¹ 及R² 分別獨立地表示氫原子或供電子性基，n表示0或1以上的整數]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. [化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, during thermocompression bonding, the flux is melted before the adhesive is hardened, and the oxide film such as the solder is reduced and removed. Therefore, it is easy to obtain further excellent connection reliability.

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

The method of manufacturing a semiconductor device of the present invention is a semiconductor device in which the respective connecting portions of a semiconductor wafer and a wiring circuit board are electrically connected to each other, or a method of manufacturing a semiconductor device in which the respective connecting portions of a plurality of semiconductor wafers are electrically connected to each other, the semiconductor The manufacturing method of a device includes the step of sealing at least a part of a connection part using the said film adhesive agent for semiconductors. According to the method of manufacturing a semiconductor device of the present invention, even when crimping is performed at a high temperature in a short time, a semiconductor device excellent in connection reliability (for example, insulation reliability) can be obtained. 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 the respective connection portions of a semiconductor wafer and a wiring circuit board are electrically connected to each other, or a semiconductor device in which respective connection portions of a plurality of semiconductor wafers are electrically connected to each other, wherein at least a part of the connection portion is electrically connected to each other The semiconductor is sealed with a cured product of a film-like adhesive. The connection reliability (for example, insulation reliability) of the semiconductor device is excellent.

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

In this specification, the "(meth)acrylate" refers to at least one of acrylate and its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl" and "(meth)acrylic acid". In addition, the numerical range indicated by "~" means a range that includes the numerical values described before and after "~" as the minimum and maximum values, respectively.

Hereinafter, suitable embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In addition, in the drawings, the same or corresponding parts are denoted with the same symbols and repeated descriptions are omitted. In addition, the positional relationship such as up, down, left, and right is regarded as based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, the size ratio of the drawing is not limited to the ratio shown in the figure.

<Film-like adhesive for semiconductors> The film-like adhesive for semiconductors of this embodiment includes a first layer ( Flux-containing layer) and a second layer (without Layer of flux).

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

According to the film-like adhesive for semiconductors of the present embodiment, in the manufacture of the semiconductor device, even during the crimping time (for example, the crimping time in the step of crimping in order to bond the semiconductor wafer and the wiring 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 thermosetting components include thermosetting resins and curing agents. As a thermosetting resin, an epoxy resin, a phenol resin (except when it contains as a hardening agent), a polyimide resin, etc. are mentioned, for example. Among these, the thermosetting resin is preferably an epoxy resin. In addition, the film-like adhesive for semiconductors of the present embodiment may optionally contain a polymer component and a filler having a weight average molecular weight of 10,000 or more.

Hereinafter, the first adhesive contains epoxy resin (hereinafter referred to as "(a) component" as appropriate), hardener (hereinafter referred to as "(b) component" as appropriate), and flux compound (hereinafter, as appropriate The case is referred to as "(c) component"), and optionally a polymer component with a weight average molecular weight of 10,000 or more (hereinafter, as the case may be referred to as "(d) component") and filler (hereinafter, as the case is referred to as "( e) Ingredients") An embodiment 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 type epoxy resin, bisphenol F type epoxy resin, naphthalene type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, 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 can be used alone or as a mixture of two or more.

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

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

[Component (b): Hardener] As component (b), for example, phenol resin hardeners, acid anhydride hardeners, amine hardeners, imidazole hardeners, and phosphine hardeners can be cited. If the component (b) contains a phenolic hydroxyl group, acid anhydride, amines, or imidazoles, it exhibits flux activity that suppresses the generation of an oxide film in the connection portion, and can improve connection reliability and insulation reliability. The hardeners are described below.

(I) Phenolic resin curing agent As the phenol resin curing agent, there are no particular restrictions as long as it has two or more phenolic hydroxyl groups in the molecule. For example, phenol novolak resin, cresol novolak resin, Phenol aralkyl resin, cresol naphthol formaldehyde condensation polymer, triphenylmethane type polyfunctional phenol resin and various polyfunctional phenol resins. These can be used alone or as a mixture of two or more.

From the viewpoint of good curability, adhesiveness, and storage stability, the equivalent ratio of the phenol resin curing agent to the component (a) (the number of moles of phenolic hydroxyl groups of the phenol resin curing agent/ (A) The number of moles of epoxy groups contained in a component) is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and still more preferably 0.5 to 1.0. If the equivalent ratio is 0.3 or more, the curability is improved and the adhesion tends to be improved. If it is 1.5 or less, unreacted phenolic hydroxyl groups will not remain excessively, the water absorption rate will be suppressed to a low value, and the insulation reliability will be improved. Propensity.

(Ii) Acid anhydride hardener As an acid anhydride hardener, for example, methylcyclohexane tetracarboxylic dianhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride and ethyl acetate can be used. Glycol bis trimellitic anhydride ester. These can be used alone or as a mixture of two or more.

From the viewpoint of good curability, adhesiveness, and storage stability, the equivalent ratio of the acid anhydride hardener to the component (a) (the number of moles of the acid anhydride group of the acid anhydride hardener/(a) The number of moles of epoxy groups contained in the component is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and still more preferably 0.5 to 1.0. If the equivalent ratio is 0.3 or more, the curability is improved, and the adhesion tends to be improved. If it is 1.5 or less, 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 curing agent As the amine-based curing agent, for example, dicyandiamine can be used.

From the viewpoint of good curability, adhesiveness, and storage stability, the equivalent ratio of the amine-based curing agent to the component (a) (the number of moles of active hydroxyl groups of the amine-based curing agent/(a) The number of moles of epoxy groups contained in the component is preferably 0.3 to 1.5, more preferably 0.4 to 1.0, and still more preferably 0.5 to 1.0. If the equivalent ratio is 0.3 or more, the curability is improved and the adhesive strength tends to be improved, and if it is 1.5 or less, unreacted amines will not remain excessively, and the insulation reliability tends to be improved.

(Iv) Imidazole-based curing agent As the imidazole-based curing agent, for example, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl- 2-Phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole 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-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4 -Methyl-5-hydroxymethylimidazole, and adducts of epoxy resin and imidazoles. Among these, from the viewpoints of excellent curability, storage stability, and connection reliability, 1-cyanoethyl-2-undecylimidazole and 1-cyano-2-phenylimidazole are preferred. , 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-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-Phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-hydroxymethylimidazole. These can be used alone or in combination of two or more kinds. Moreover, it can also be set as the latent hardening agent which microencapsulated these.

The content of the imidazole-based hardener is preferably 0.1 parts by mass to 20 parts by mass, and more preferably 0.1 parts by mass to 10 parts by mass relative to 100 parts by mass of the component (a). If the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curing property tends to be improved. In addition, when the content of the imidazole-based curing agent is 20 parts by mass or less, the fluidity of the first adhesive during pressure bonding can be ensured, and the first adhesive between the connecting portions can be sufficiently eliminated. As a result, the first adhesive agent can be prevented from being hardened in a state where the solder is interposed between the solder and the connection portion, and therefore, connection failure is less likely to occur.

(V) Phosphine-based hardeners. Examples of phosphine-based hardeners include triphenylphosphine, tetraphenylphosphonium tetraphenyl borate, tetraphenylphosphonium tetra(4-methylphenyl) borate, and tetraphenyl Phosphonium (4-fluorophenyl) borate.

The content of the phosphine-based hardener is preferably 0.1 parts by mass to 10 parts by mass, and more preferably 0.1 parts by mass to 5 parts by mass relative to 100 parts by mass of the component (a). If the content of the phosphine-based hardening agent is 0.1 parts by mass or more, the curability tends to be improved, and if it is 10 parts by mass or less, the first adhesive will not harden before the formation of the metal joint, and poor connection will be less likely to occur.

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

When the first adhesive contains a phenol resin-based curing agent, an acid anhydride-based curing agent, or an amine-based curing agent as the component (b), it exhibits flux activity for removing the oxide film, and the connection reliability can be further improved.

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

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 them, a compound having two carboxyl groups is preferred. A compound having two carboxyl groups is less volatile than a compound having one carboxyl group (monocarboxylic acid) even due to the high temperature at the time of connection, and the generation of pores can be further suppressed. In addition, if a compound having two carboxyl groups is used, compared to the case of using a compound having three or more carboxyl groups, the increase in the viscosity of the film-like adhesive for semiconductors during storage, during connection work, etc., can be further suppressed. 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. [化2]

In the 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, R ¹ is preferably the electron donating property. In this embodiment, the first adhesive contains an epoxy resin and a hardening agent, and further contains a compound in which R ¹ is an electron-donating group among the compounds having a group represented by formula (1), thereby Even when it is used as a film-like adhesive for semiconductors in a flip-chip connection method for metal bonding, a semiconductor device with more excellent reflow resistance and connection reliability can be produced.

In order to improve the reflow resistance, it is necessary to suppress the decrease in adhesive force after moisture absorption at high temperature. Conventionally, carboxylic acids have been used as flux compounds. However, the present inventors believe that in the conventional flux compounds, the adhesive force is reduced due to the following reasons.

Generally, the epoxy resin reacts with the hardener to proceed the hardening reaction, but in this case, the carboxylic acid as the flux compound is included in the hardening reaction. That is, the epoxy group of the epoxy resin reacts with the carboxyl group of the flux compound to form an ester bond in some cases. The ester bond is likely to undergo hydrolysis due to moisture absorption, etc., and it is considered that the decomposition of the ester bond is a cause of the decrease in adhesive force after moisture absorption.

In contrast, among the compounds having a group represented by formula (1) in the first adhesive, 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 nearby In the case of carboxyl group, the flux activity is sufficiently obtained, and even in the case where the ester bond is formed, the electron density of the ester bond is increased by the electron donating group, and the decomposition of the ester bond is suppressed . In addition, it is considered that the presence of a substituent (electron-donating group) near the carboxyl group prevents the reaction of the carboxyl group with the epoxy resin due to steric hindrance, and it is difficult to form an ester bond.

For these reasons, in the case of using a first adhesive that further contains a compound having a group represented by formula (1), where R ¹ is an electron-donating group, it is difficult to produce a composition due to moisture absorption, etc. 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, it can also be expected that the hardening reaction of the epoxy resin and the hardener is sufficiently advanced to achieve a reliable connection. The effect of improving sex.

If the electron donating property of the electron donating group becomes stronger, 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 in a well-balanced manner.

Examples of the electron-donating group include an alkyl group, a hydroxyl group, an amino group, an alkoxy group, and an alkylamino group. The electron-donating group is preferably a group that is not easily reacted with other components (for example, the epoxy resin of component (a)). Specifically, an alkyl group, a hydroxyl group, or an alkoxy group is preferable, and an alkyl group is more preferable .

As the alkyl group, an alkyl group having 1 to 10 carbon atoms is preferred, and an alkyl group having 1 to 5 carbon atoms is more preferred. There is a tendency that the greater the number of carbon atoms in the alkyl group, the greater the electron donating property and steric hindrance. An alkyl group having a carbon number in the above-mentioned range has excellent electron donating properties and a balance of steric hindrance. Therefore, according to the alkyl group, the effects of the present invention can be more remarkably exhibited.

In addition, 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 of electron donation and steric hindrance. For example, when the flux compound is a compound represented by the following formula (2), and the electron-donating group is a linear alkyl group, the carbon number of the alkyl group is 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. The more the carbon number of the alkoxy group, the greater the electron donating property and steric hindrance. An alkoxy group having a carbon number in the above-mentioned range has excellent electron donating properties and a balance of steric hindrance. Therefore, according to the alkoxy group, the effects of the present invention can be exhibited more remarkably.

In addition, the alkyl portion of the alkoxy group may be linear or branched, and is preferably linear. When the alkoxy group is linear, the carbon number of the alkoxy group is preferably less than or equal to the carbon number of the main chain of the flux compound from the viewpoint of the balance of electron donation and steric hindrance. For example, when the flux compound is a compound represented by the following formula (2) and the electron-donating group is a linear alkoxy group, the carbon number of the alkoxy group is preferably 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. As the monoalkylamino group, a monoalkylalkyl group having 1 to 10 carbon atoms is preferred, and a monoalkylamino group having 1 to 5 carbon atoms is more preferred. The alkyl portion of the monoalkylamino group may be linear or branched, and is preferably linear.

As the dialkylamino group, a dialkylalkyl group having 2 to 20 carbon atoms is preferable, and a dialkylamino group having 2 to 10 carbon atoms is more preferable. The alkyl part 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), the reflow resistance and connection reliability of the semiconductor device can be further improved.

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. In addition, the electron-donating group represented ^{by R 2} is the same as the example of the electron-donating group described ^{as R 1.} For the same reason as explained in the formula (1), R ¹ in the formula (2) is preferably an electron-donating group.

In formula (2), n is preferably 1 or more. If n is 1 or more, compared to the case where n is 0, the flux compound is less likely to volatilize 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, and may be 6 or less or 4 or less. If n is 15 or less, further excellent connection reliability can be obtained.

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

[化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.

In formula (3), m is preferably 10 or less, more preferably 5 or less, and still more preferably 3 or less. If 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 more excellent connection reliability, ^{at least one of R 1} and R ² is preferably an electron-donating group. If R ¹ is an electron-donating group and R ² is a hydrogen atom, the melting point tends to be lower, and the connection reliability of the semiconductor device may be further improved. In addition, if R ¹ and R ² are different electron-donating groups, compared to the case where R ¹ and R ² are the same electron-donating group, the melting point tends to be lower, which may further improve the semiconductor device’s Connection reliability.

Furthermore, in formula (3), if R ¹ and R ² are the same electron-donating group, they tend to have a symmetrical structure and the melting point tends to be high. However, in this case, the effects of the present invention can also be sufficiently obtained. In particular, when the melting point is 150°C or lower and is sufficiently low, even if R ¹ and R ² are the same group, the same level of connection reliability ^{can be obtained as when R 1} and R ^{2 are different groups.}

As the flux compound, for example, those selected from 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 the 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 still more preferably 130°C or lower. This kind of flux compound tends to fully exhibit flux activity before the hardening reaction between the epoxy resin and the hardener occurs. Therefore, according to the semiconductor film-like adhesive using the first adhesive containing such a flux compound, a semiconductor device with more excellent connection reliability can be realized. In addition, the melting point of the flux compound is preferably 25°C or higher, more preferably 50°C or higher. In addition, the flux compound is preferably solid at room temperature (25°C).

The melting point of the flux compound can be measured using a usual melting point measuring device. By pulverizing the sample for measuring the melting point into fine powder and using a small amount, the melting point can be obtained while reducing the deviation of the temperature in the sample. As the sample container, a capillary tube with one end closed is often used. However, depending on the measuring device, there is also a container that is sandwiched between two cover glasses for microscopes. In addition, if the temperature is increased sharply, a temperature gradient will be generated between the sample and the thermometer and measurement errors will occur. Therefore, the heating at the time of measuring the melting point is ideally measured at a rate of increase of 1°C or less per minute. .

As described above, the sample for measuring the melting point is prepared as a fine powder, so the sample before melting is opaque due to diffuse reflection on the surface. Generally, the temperature at which the appearance of the sample begins to become transparent is set as the lower limit point of the melting point, and the temperature at which the sample is completely melted is set as the upper limit point. There are various forms of measuring devices. The most classic device uses the following device: a capillary filled with a sample is installed on a double tube thermometer, and a warm bath is used for heating. In order to attach the capillary tube to the double-tube thermometer, a high-viscosity liquid is used as the liquid in the warm bath. In most cases, concentrated sulfuric acid or silicon oil is used, and the sample is installed near the reservoir at the tip of the thermometer. . In addition, the melting point measuring device may also use a device that uses a metal heat block for heating, adjusts the heating while measuring the light transmittance, and automatically determines the melting point.

In addition, in this specification, a melting point of 150°C or lower means that the upper limit point of the melting point is 150°C or lower, and the melting point of 25°C or higher means that the lower limit point 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, more preferably 0.5% by mass to 5% by mass.

[Component (d): A polymer component with a weight average molecular weight of 10,000 or more]

The first adhesive may optionally contain a polymer component (component (d)) having a weight average molecular weight of 10,000 or more. The first adhesive agent containing the component (d) is more excellent in heat resistance and film forming properties.

As the (d) component, for example, phenoxy resin, polyimide resin, polyimide resin, polycarbodiimide resin, cyanate resin, acrylic resin, polyester resin, polyethylene resin, Polyether resin, polyether imine resin, polyvinyl acetal resin, urethane resin and acrylic rubber. Among these, from the viewpoint of excellent heat resistance and film forming properties, phenoxy resins, polyimide resins, urethane resins, acrylic rubbers, cyanate ester resins, and polycarbodiamide resins are preferred. The 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 can also be used individually or as a mixture or copolymer of two or more types. However, the compound corresponding to the component (a) and the compound corresponding to the component (e) are not included in the component (d).

(D) The weight average molecular weight of the component is, for example, 10,000 or more, preferably 20,000 or more, and more preferably 30,000 or more. According to such a component (d), the heat resistance and film formation properties of the first adhesive can be further improved. (D) The weight average molecular weight of the component is preferably 200,000 or less, more preferably 100,000 or less. According to such a component (d), the heat resistance of the first adhesive can be further improved. 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, the so-called weight average molecular weight refers to the weight average molecular weight when measured by polystyrene conversion using a high performance liquid chromatograph (manufactured by Shimadzu Corporation, trade name: C-R4A) . In the measurement, for example, the following conditions can be used. Detector: LV4000 ultraviolet (Ultraviolet, UV) detector (Detector) (manufactured by Hitachi, Ltd., trade name) Pump: L6000 pump (Pump) (manufactured by Hitachi, Ltd., trade name) Column: Gilpa ( Gelpack) GL-S300MDT-5 (2 pieces in total) (manufactured by Hitachi Chemical Co., Ltd., trade name) Chaotropic solution: 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 the first adhesive contains component (d), the ratio _Ca /C _{d (mass ratio) of the content of (a) component C a} to the content of (d) component C _d is preferably 0.01-5, more preferably It is 0.05-3, More preferably, it is 0.1-2. If the ratio C _a /C _{d is} set to 0.01 or more, better curability and adhesiveness can be obtained, and if the ratio C _a /C _{d is} set to 5 or less, better film forming properties can be obtained.

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

As the (e) component, an inorganic filler (inorganic particle), an organic filler (organic particle), etc. are mentioned. Examples of inorganic fillers include insulating inorganic fillers such as glass, silicon dioxide, aluminum oxide, titanium oxide, mica, and boron nitride. Among them, it is preferably selected from silicon dioxide, aluminum oxide, titanium oxide, and boron nitride. At least one of the formed group is more preferably at least one selected from the group consisting of silicon dioxide, aluminum oxide, and boron nitride. The insulating inorganic filler may also be whiskers. Examples of the whiskers include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, boron nitride, and the like. As an organic filler, a resin filler (resin particle) is mentioned, for example. As a resin filler, polyurethane, polyimide, etc. are mentioned. 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 formation.

From the viewpoint of easy adjustment of the modulus of elasticity to the desired range, and from the viewpoint that warpage can be suppressed and the generation of voids can be more sufficiently reduced, and thus excellent connection reliability can be obtained, the component (e) Based on the total mass, 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 or less.

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

From the viewpoint of easy adjustment of the modulus of elasticity to the desired range, and from the viewpoint that warpage can be suppressed and the generation of voids can be more sufficiently reduced, and thus excellent connection reliability can be obtained, the component (e) Based on the total mass, 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) The component may substantially include only insulating fillers. That is, the (e) component may not contain a conductive filler substantially. The term "substantially not contained" 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).

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

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

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

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

[Other components] Additives such as antioxidants, silane coupling agents, titanium coupling agents, leveling agents, and ion scavengers can also be blended in the first adhesive. These can be used individually by 1 type or in combination of 2 or more types. Regarding these blending amounts, it is only necessary to adjust them appropriately so as to exhibit the effects of the respective additives.

From the viewpoint of reliability, the minimum melt viscosity of the first adhesive is preferably 1000 Pa·s or more, more preferably 1500 Pa·s or more, and still more preferably 2000 Pa·s or more. If the minimum melt viscosity is 1000 Pa･s or more, the thermal expansion of the voids involved during packaging is suppressed, and the possibility of peeling during long-term use (such as reliability testing) is reduced. On the other hand, since the first layer is fully eliminated during solder connection and resin jamming is reduced, thereby providing excellent electrical connection reliability, the minimum melt viscosity of the first adhesive is preferably 10000 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 lowest melt viscosity of the first adhesive is preferably 1000 Pa･s～10000 Pa･s, more preferably 1500 Pa･s～5000 Pa･s, and even more preferably 2000 Pa･s～ 4000 Pa･s. Furthermore, the melt viscosity can be measured using a rotary rheometer (for example, ARES-G2 manufactured by TA Instruments). In addition, the melt viscosity is the 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 term "substantially not contained" 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 of the second adhesive after being held at 200° C. for 5 seconds is preferably 80% or more. As such a second adhesive agent, for example, a radical curing type adhesive agent can be cited. The reason why the effect of the present invention is remarkably obtained by such an adhesive is not clear, but the inventors of the present invention speculate as follows.

That is, in conventional film adhesives containing flux compounds, the flux component deactivates radicals, and therefore radical curing systems cannot be applied. In most cases, cationic curing systems using epoxy groups or the like are applied. In this hardening system (reaction system), nucleophilic addition reaction is used for hardening, so the hardening speed is slow, and pores may be generated after crimping. In conventional film adhesives, it is presumed that defects (for example, peeling of semiconductor materials at reflow temperatures around 260°C, poor connection of connecting parts, etc.) have occurred due to voids during the packaging. On the other hand, the second adhesive does not substantially contain a flux compound, so the curing system can be a radical curing system, and a sufficient curing speed can be obtained. Therefore, it is presumed that the use of the second adhesive in the second layer makes it difficult to generate voids even when pressure bonding is performed at a high temperature in a short time, and the effect of the present invention becomes remarkable. In addition, in the present embodiment, since a sufficient curing rate can be obtained, even when solder is used in the connection portion, for example, the film-like adhesive can be cured in a temperature range lower than the melting temperature of the solder. Therefore, it is possible to sufficiently suppress the occurrence of scattering and flow of the solder 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), as necessary An embodiment of the polymer component (hereinafter referred to as "(C) component" as appropriate) and filler (hereinafter referred to as "(D) component" as appropriate)) will be described.

[(A) Component: Radical Polymerizable Compound] The (A) component is a compound capable of undergoing a radical polymerization reaction along with the generation of free radicals by heat, light, radiation, electrochemical action, or the like. As (A) component, a (meth)acrylic compound, a vinyl compound, etc. are mentioned. In terms of durability, electrical insulation, and heat resistance, the (A) component is preferably a (meth)acrylic compound. If the (meth)acrylic compound is a compound having one or more (meth)acrylic groups ((meth)acrylic groups) in the molecule, it is not particularly limited. For example, it can be used: containing bisphenol A type, bisphenol F type, naphthalene type, phenol novolac type, cresol novolac type, phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, sulphur type, adamantane type or heterotrimer A (meth)acrylic compound with a cyanic acid type skeleton; various polyfunctional (meth)acrylic compounds (except for the (meth)acrylic compound containing the skeleton), etc. 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 the generation of pores, the component (A) preferably has a bisphenol A type skeleton, a bisphenol F type skeleton, a naphthalene type skeleton, a sulphur type skeleton, an adamantane type skeleton or The isocyanuric acid type skeleton, more preferably, has a cyanuric type skeleton. From the viewpoint that the generation of voids can be further suppressed, the (A) component is more preferably a (meth)acrylate having any of the above-mentioned skeletons.

(A) The component is preferably solid at room temperature (25°C). Compared with the liquid state, the solid state is less likely to generate voids. In addition, the second adhesive before curing (B-stage) has a small tack and is excellent in handleability. Examples of the component (A) that are solid at room temperature (25°C) include (meth)acrylates having a bisphenol A type skeleton, a sulphur type skeleton, an adamantane type skeleton, or an isocyanuric acid type skeleton. Wait.

(A) The number of functional groups of the (meth)acrylic group in the component is preferably 3 or less. In the case of a large number of functional groups, the hardened network rapidly expands, and sometimes unreacted groups remain. On the other hand, if the number of functional groups is 3 or less, the number of functional groups will not be too large, and the curing in a short period of time will be easily carried out sufficiently, and therefore the reduction in the curing reaction rate will be easily suppressed.

(A) The molecular weight of the component is preferably less than 2,000, more preferably 1,000 or less. (A) The smaller the molecular weight of the component, the easier the reaction proceeds, and the higher the curing reaction rate.

From the viewpoint of suppressing the reduction of hardening components and making it easy to fully control the resin flow after hardening, the content of component (A) is preferably 10% by mass or more, more preferably 15% by mass based on the total mass of the second adhesive %above. From the viewpoint of suppressing the hardening of the cured product and easily suppressing the increase in the warpage of the package, the content of the component (A) is preferably 50% by mass or less, more preferably 40% based on the total mass of the second adhesive. Less than mass%. 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 the decrease in curability and easily suppressing the decrease in adhesive strength, the content of component (A) is preferably 0.01 part by mass or more, more preferably 0.05 part by mass or more, and more preferably, relative to 1 part by mass of component (C) It is 0.1 parts by mass or more. From the viewpoint of easily suppressing the decrease in film formability, the content of the (A) component is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less with respect to 1 part by mass of the (C) component. From these viewpoints, relative to 1 part by mass of (C) component, the content of (A) component is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and still more preferably 0.1 Parts by mass ~ 5 parts by mass.

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

Examples of thermal radical generators include azo compounds and peroxides (organic peroxides etc.). As the thermal radical generator, peroxides are preferred, and organic peroxides are more preferred. In this case, the radical reaction does not proceed in the step of drying the solvent when the film is formed, and the handling and storage stability are excellent. Therefore, when peroxide is used as a thermal radical generator, it is easy to obtain further excellent connection reliability. Examples of organic peroxides include ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, peroxyesters, and the like. The organic peroxide is preferably at least one selected from the group consisting of hydroperoxides, dialkyl peroxides, and peroxyesters from the viewpoint of excellent storage stability. Furthermore, as the organic peroxide, from the viewpoint of excellent heat resistance, it is preferably at least one selected from the group consisting of hydroperoxides and dialkyl peroxides. Examples of the dialkyl peroxide include dicumyl peroxide and di-tertiary butyl peroxide.

From the viewpoint of ease of curing sufficiently, the content of the component (B) is preferably 0.5 part by mass or more, and more preferably 1 part by mass or more with respect to 100 parts by mass of the (A) component. With respect to 100 parts by mass of (A) component, the content of (B) component is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less. If the upper limit of the content of the component (B) is in the above range, the hardening progresses rapidly and the increase of reaction points is suppressed, thereby suppressing the shortening of the molecular chain and the remaining of unreacted groups. Therefore, if the upper limit of the content of the (B) component is the above range, it is easy to suppress the decrease in reliability. From these viewpoints, the content of the component (B) is preferably 0.5 parts by mass to 10 parts by mass, and more preferably 1 part by mass to 5 parts by mass relative to 100 parts by mass of the (A) component.

[Component (C): Polymer component] The second adhesive may further contain a polymer component. (C) Component can include: epoxy resin, phenoxy resin, polyimide resin, polyimide resin, polycarbodiimide resin, cyanate resin, (meth)acrylic resin, polyester resin , Polyethylene resin, polyether sulfide resin, polyether imide resin, polyvinyl acetal resin, urethane resin, acrylic rubber, etc., among them, from the viewpoint of excellent heat resistance and film formability, It is preferably selected from epoxy resins, phenoxy resins, polyimide resins, (meth)acrylic resins, urethane resins, acrylic rubbers, cyanate ester resins, and polycarbodiimide resins. At least one of the group consisting of, more preferably selected from the group consisting of epoxy resin, phenoxy resin, polyimide resin, (meth)acrylic resin, urethane resin and acrylic rubber At least one of them. (C) Component can also be used individually by 1 type or as a mixture or copolymer of 2 or more types. However, the compound corresponding to (A) component and the compound corresponding to (D) component are not included in (C) component.

From the viewpoint of excellent adhesion of the film-like adhesive for semiconductors to substrates or wafers, the glass transition temperature (Tg) of the component (C) is preferably 120°C or less, more preferably 100°C or less, and still more preferably Below 85°C. In these ranges, the bumps formed on the semiconductor wafer, the unevenness of the electrodes or wiring patterns formed on the substrate, etc. can be easily filled with the film-like adhesive for semiconductors (it is easy to suppress the initiation of the curing reaction) , It is easy to suppress the residual bubbles and the generation of pores. Furthermore, the Tg is measured using a differential scanning calorimetry (Differential Scanning Calorimetry, DSC) (manufactured by Perkin Elmer Japan Co., Ltd., trade name: DSC-7 type) in a sample amount of 10 mg , The heating rate is 10℃/min, and the measuring environment: Tg when measuring under the condition of air.

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

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

From the viewpoint of suppressing the decrease in heat release and the viewpoints of easily suppressing the generation of voids and increasing the moisture absorption rate, based on the total mass of the second adhesive, the content of component (D) is preferably 15% by mass or more , More preferably 20% by mass or more, and still more preferably 40% by mass or more. In terms of easily suppressing the increase in viscosity and lowering of the fluidity of the second adhesive and the occurrence of trapping of the filler to the connection part, it is easy to suppress the 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, more preferably 80% by mass or less. From these viewpoints, based on the total mass of the second adhesive, the content of component (D) is preferably 15% by mass to 90% by mass, more preferably 20% by mass to 80% by mass, and still more preferably 40% to 80% by mass.

The minimum melt viscosity of the second adhesive agent is not particularly limited, and may be a value higher than the minimum melt viscosity of the first adhesive agent, or may be a value lower than the minimum melt viscosity of the first adhesive agent. The minimum melt viscosity of the second adhesive agent may also be within a preferable range of the minimum melt viscosity of the first adhesive agent (for example, 1000 Pa･s～10000 Pa･s). The lowest melt viscosity of the second adhesive can be measured by the same method as the lowest melt viscosity of the first adhesive.

[Other components] A polymerizable compound other than a radical polymerizable compound (for example, a cation polymerizable compound and an anionic polymerizable compound) may be blended in the second adhesive. In addition, the same other components as 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. Regarding these blending amounts, it is only necessary to adjust them appropriately so as to exhibit the effects of the respective additives.

The curing reaction rate after holding the second adhesive at 200° C. for 5 seconds is preferably 80% or more, more preferably 90% or more. If the hardening reaction rate of 200°C (below the solder melting temperature)/5 seconds is 80% or more, it is easy to prevent the solder from scattering and flowing during connection (above the solder melting temperature) and the reliability of the connection is reduced. The curing reaction rate can be obtained by the following method: Put 10 mg of the second adhesive (unhardened layer without flux) into the aluminum pot, and use DSC (Perkin Elmer Japan) ) Manufactured by Co., Ltd., trade name: DSC-7 type) to measure the calorific value. Specifically, 10 mg of the second adhesive (unhardened layer not containing flux) is put into an aluminum pan, and the measurement sample obtained therefrom is placed on a hot plate heated to 200°C, After 5 seconds, the measurement sample was removed from the hot plate. 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-[heat value of the measured sample after heat treatment]/[heat value of the untreated measurement sample])×100

If the second adhesive contains an anionic polymerizable epoxy resin (especially an epoxy resin with a weight average molecular weight of 10,000 or more), it may be difficult to adjust the curing reaction rate to 80% or more. It is preferable that the content of the epoxy resin is 20 parts by mass or less with respect to 80 parts by mass of the component (A), and it is more preferable that the epoxy resin is not contained.

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 metal such as solder is melted to form a connection, it exhibits more excellent hardenability.

Regarding the thickness of the film-like adhesive for semiconductors of the present embodiment, when the sum of the heights of the connection portions is x and the total thickness of the film-like adhesive for semiconductors is y, it is the value at the time of pressure bonding. From the viewpoint of connectivity and filling properties 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-like adhesive for semiconductors may be, for example, 10 μm to 100 μm, may be 10 μm to 80 μm, or may be 10 μm to 50 μm.

The thickness of the first layer may be, for example, 1 μm-50 μm, 3 μm-50 μm, 4 μm-30 μm, or 5 μm-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-like adhesive for semiconductors of this embodiment may further include other layers in addition to the first layer and the second layer. For example, the semiconductor film adhesive of this embodiment may include a mixed layer including the first layer and the second layer. In addition, the film-like adhesive for semiconductors of this embodiment may include a base on the surface of the first layer opposite to the second layer, and/or the 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-like 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 peel off 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 adhesive is preferably 1000 Pa·s or more, more preferably 1500 Pa·s or more, and still more preferably 2000 Pa·s or more. If the minimum melt viscosity is 1000 Pa･s or more, the thermal expansion of the voids involved during packaging is suppressed, and the possibility of peeling during long-term use (such as reliability testing) is reduced. On the other hand, since the first layer is fully eliminated during solder connection and resin jamming is reduced, thereby providing excellent electrical connection reliability, the minimum melt viscosity of the film adhesive is preferably 10000 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 film adhesive is preferably 1000 Pa･s～10000 Pa･s, more preferably 1500 Pa･s～5000 Pa･s, and even more preferably 2000 Pa･s～ 4000 Pa･s. The lowest melt viscosity of the film adhesive can be measured by the same method as the lowest melt viscosity of the first adhesive.

<Method for manufacturing film-like adhesive for semiconductors> The film-like adhesive for semiconductors of this embodiment can be obtained, for example, by preparing a first film-like adhesive including a first layer and a second film including a second layer The first film-shaped adhesive including the first layer and the second film-shaped adhesive including the second layer are bonded together.

In the step of preparing the first film-like adhesive, for example, first add (a) component, (b) component, and (c) component, and if necessary, (d) component and (e) component and other components are added to In an organic solvent, a resin varnish (coating varnish) is prepared by dissolving or dispersing it by stirring, mixing, kneading, etc. Then, on the base film or protective film that has been subjected to mold release treatment, use a knife coater, roll coater, applicator, etc., to coat the resin varnish, and then heat it to reduce the organic solvent. The first layer containing the first adhesive is formed on the base film or the protective film.

The organic solvent used in the preparation of the resin varnish is preferably one having the property of uniformly dissolving or dispersing each component, for example, dimethylformamide, dimethylacetamide, N-methyl -2-pyrrolidone, dimethyl sulfide, diethylene glycol dimethyl ether, toluene, benzene, xylene, methyl ethyl ketone, tetrahydrofuran, ethyl cellosolve, ethyl cellosolve acetate , Butyl cellosolve, dioxane, cyclohexanone, and ethyl acetate. These organic solvents can be used alone or in combination of two or more. The stirring, mixing and kneading at the time of preparing the resin varnish can be performed using, for example, a stirrer, an attritor, 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 the 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 also include an adhesive layer on one surface.

The drying conditions when the organic solvent is volatilized from the resin varnish applied on the substrate film are preferably set to a condition where the organic solvent is sufficiently volatilized, and specifically, heating at 50°C to 200°C for 0.1 to 90 minutes is preferred . 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 with respect to the total mass of the first film-like adhesive.

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

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

The film-like 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 second layer The other of the first layer or the second layer is formed. The first layer and the second layer can be formed by the same method as the method for forming the first layer and the second layer in the production of the film-like adhesive with a substrate.

The film-like adhesive for semiconductors of this embodiment can also be obtained by forming the first layer and the second layer substantially simultaneously on the base film, for example. This method may be a method of forming the first layer and the second layer by substantially simultaneously applying the first adhesive and the second adhesive and drying them at once (simultaneous multi-layer coating method), or by coating A method in which the first adhesive is applied and then the second adhesive is applied and dried at one time to form the first layer and the 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 showing an embodiment of the semiconductor device of the present invention. As shown in FIG. 1(a), the semiconductor device 100 has: a semiconductor wafer 10 and a substrate (circuit wiring board) 20 facing each other, wirings 15 respectively arranged on mutually facing surfaces of the semiconductor wafer 10 and the substrate 20, and a semiconductor device The connection bumps 30 connecting the wiring 15 of the wafer 10 and the substrate 20 to each other, and the cured product containing the adhesive (first adhesive and second adhesive) filled in the gap between the semiconductor wafer 10 and the substrate 20 without gaps的封部40。 The seal 40. The semiconductor chip 10 and the substrate 20 are connected via flip chip via wiring 15 and connection bumps 30. The wiring 15 and the connection bump 30 are sealed by a hardened material of the adhesive and blocked from the external environment. The sealing part 40 has the upper part 40a containing the hardened|cured material of a 1st adhesive agent, and the lower part 40b containing the hardened|cured material of a 2nd adhesive agent.

As shown in FIG. 1(b), the semiconductor device 200 has: a semiconductor wafer 10 and a substrate 20 facing each other, bumps 32 respectively disposed on the mutually facing surfaces of the semiconductor wafer 10 and the substrate 20, and includes filling without gaps The sealing portion 40 of the cured product of the adhesive (the first adhesive and the second adhesive) in the gap between the semiconductor wafer 10 and the substrate 20. The semiconductor chip 10 and the substrate 20 are connected to each other by the bumps 32 facing each other to be connected by flip chip. The bump 32 is sealed by the hardened material of the adhesive to be blocked from the external environment. The sealing part 40 has the upper part 40a containing the hardened|cured material of a 1st adhesive agent, and the lower part 40b containing the hardened|cured material of a 2nd adhesive agent.

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

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

The substrate 20 is not particularly limited if it is a circuit substrate. It can be used with glass epoxy, polyimide, polyester, ceramic, epoxy, bismaleimide triazine, etc. as the main component On the surface of the insulating substrate, the unnecessary part of the metal film is etched away to form a circuit substrate with wiring (wiring pattern) 15; on the surface of the insulating substrate, the wiring 15 is formed by metal plating or the like Circuit board; by printing a conductive material on the surface of the insulating substrate to form a circuit board with wiring 15 and the like.

The connecting parts such as the wiring 15, the bump 32 contain gold, silver, copper, solder (main components such as tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc.), nickel, tin, Lead etc. may contain multiple metals as the main component.

Among the metals, from the viewpoint of forming a package excellent in electrical conductivity and thermal conductivity of the connection portion, gold, silver, and copper are preferred, and silver and copper are more preferred. From the viewpoint of forming a cost-reduced package, silver, copper, and solder, which are inexpensive materials, are preferable, copper and solder are more preferable, and solder is still more preferable. If 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 oxide film, gold, silver, copper, and solder are preferred. , More preferably gold, silver, and solder, and still more preferably gold, silver.

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

In addition, in the semiconductor device of the present embodiment, the structure (package) shown in the semiconductor device 100 to the semiconductor device 400 may be stacked in multiple layers. In this case, the semiconductor device 100 to the semiconductor device 400 may also include gold, silver, copper, solder (the main components are, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc. ), bumps such as tin and nickel, 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 the semiconductor device of the present invention, which 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 chip 10 via the connection bumps 30, whereby the semiconductor chip 10 and the interposer 50 are flip-chip connect. The gap between the semiconductor wafer 10 and the interposer 50 is filled with cured products of adhesives (first adhesive and second adhesive) without any gaps, thereby constituting the sealing portion 40. On the surface of the semiconductor wafer 10 on the opposite side to the interposer 50, the semiconductor wafer 10 is laminated via 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 through electrodes 34 filled in holes penetrating the inside of the semiconductor wafer 10. In addition, as the 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 backside of a semiconductor chip that is not normally used. Furthermore, since the through electrode 34 is vertically inserted into 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, and a flexible connection can be made. In this 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 with a high degree of freedom such as area bump wafer technology, the semiconductor wafer can be directly packaged on a mother board without an interposer. The film-like adhesive for semiconductors of this embodiment can also be applied to such a case where a semiconductor chip is directly packaged on a mother board. In addition, in the case of laminating two wiring circuit boards, the film-like adhesive for semiconductors of this embodiment can also be applied when sealing the gap between the boards.

<The manufacturing method of a semiconductor device> The manufacturing method of the semiconductor device of this embodiment is demonstrated below using FIG. 4(a)-FIG. 4(c). 4(a) to 4(c) are diagrams schematically showing an embodiment of the method of manufacturing a semiconductor device of the present invention, and FIGS. 4(a), 4(b), and 4(c) showing each step ) Shows the cross section of the semiconductor device.

First, as shown in FIG. 4( a ), on the substrate 20 with the wiring 15, a solder resist 60 having an opening at a position for forming the connection bump 30 is formed. The solder resist 60 is not necessarily provided. However, by providing the solder resist on the substrate 20, the occurrence of bridging between the wirings 15 can be suppressed, and the connection reliability and the insulation reliability can be improved. The solder resist 60 can be formed using, for example, ink for a commercially available solder resist for packaging. Specific examples of commercially available inks for solder resists for packaging 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 ), connecting bumps 30 are formed at the openings of the solder resist 60. Then, as shown in FIG. 4(b), on the substrate 20 on which the connection bumps 30 and the solder resist 60 are formed, the surface of the second layer 41b containing the second adhesive is attached to the substrate 20 side. The film-like adhesive for semiconductors of this embodiment (hereinafter, referred to as “film-like adhesive” as appropriate) 41. The film-like adhesive 41 can be applied by heat pressing, roll lamination, vacuum lamination, or the like. The supply area and thickness of the film adhesive 41 are appropriately set according to the size of the semiconductor wafer 10 and the substrate 20, the height of the connection bump 30, and the like. In addition, the sticking of the film-like adhesive 41 may be performed so that the surface on the side of the first layer 41a including the first adhesive becomes the side of the substrate 20.

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 connecting device such as a flip chip bonder. Then, the semiconductor wafer 10 and the substrate 20 are heated at a temperature higher than the melting point of the connecting bump 30 and pressure-bonded, thereby connecting the semiconductor wafer 10 and the substrate 20 as shown in FIG. 4(c), and by including The sealing portion 40 of the cured product of the film 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 5 seconds or less, for example. In this embodiment, since the film-like adhesive 41 of the above-mentioned embodiment is used, even if the pressure bonding time is 5 seconds or less, a semiconductor device with excellent connection reliability can be obtained.

In the manufacturing method of the semiconductor device of this embodiment, it is also possible to temporarily fix the position (with a film-like adhesive for semiconductor interposed) after the positioning, and heat-treat it in a reflow furnace to connect the bumps. 30 melts and connects the semiconductor wafer 10 and the substrate 20. Since it is not necessary to form metal joints during the temporary fixing stage, compared with the aforementioned method of pressing while heating, it is possible to perform pressing with a low load, a short time, and a low temperature, and the productivity is improved. Suppress the deterioration of the connection part.

In addition, after the semiconductor wafer 10 and the substrate 20 are connected, heat treatment may be performed in 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-like adhesive is completely cured. The heating temperature and heating time can be set appropriately.

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

From the viewpoint of productivity improvement, it can also be obtained on the semiconductor wafer 10 by supplying the film-like adhesive for semiconductor to a semiconductor wafer to which a plurality of semiconductor wafers 10 are connected, and then dicing the wafer to separate it into pieces. A structure provided with a film-like adhesive for semiconductors. The film-like adhesive for semiconductors may be supplied by embedding wiring, bumps, etc. on the semiconductor wafer 10 by, for example, a bonding method such as heating and pressing, roll lamination, and vacuum lamination. In this case, the supply amount of the resin is fixed, so the productivity is improved, and the generation of voids and the decrease in crystal cut properties due to insufficient filling can be suppressed.

The connection load can be set in consideration of the deviation in the number and height of the connection bumps 30, the deformation amount of the connection bumps 30 generated by pressure, or the wiring that receives the bumps of the connection portion. 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 it may be a temperature at which the metal bonding of each connection portion (bump and wiring) can be formed. 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 differs depending on the constituent metal of the connection part, but from the viewpoint of productivity improvement, 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-like adhesive for semiconductors of the present embodiment all show excellent reflow resistance and connection reliability.

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

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

<Preparation of a single-layer film including a layer containing a flux> The compounds used in the preparation of a single-layer film including a layer containing a flux are shown below. (A) Epoxy resin ・Multifunctional solid epoxy resin containing triphenolmethane 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 adduct (manufactured by Shikoku Chemical Industry Co., Ltd., product (Name "2MAOK-PW")

(c) Flux

‧Glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd., melting point is about 98℃)

‧2-Methylglutaric acid (manufactured by Sigma Aldrich, melting point about 78℃)

‧3-Methylglutaric acid (Tokyo Chemical Co., Ltd., melting point about 87℃)

(d) Polymer components

‧Phenoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name "ZX1356-2", Tg: about 71°C, weight average molecular weight Mw: about 63000)

‧Phenoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name "FX-293", Tg: about 160°C, weight average molecular weight Mw: about 40,000)

(e) Packing

‧Silica filler (manufactured by Admatechs Co., Ltd., trade name "SE2050", average particle size: 0.5μm)

‧Silane oxide surface treatment filler (manufactured by Admatechs Co., Ltd., SE2050-SEJ, average particle size: 0.5μm)

‧Methacrylic acid surface treatment nano-silica filler (manufactured by Admatechs Co., Ltd., trade name "YA100C-MLE", average particle size: about 100 nm) ·Methacrylic acid surface treatment nano-silica filler Silicon 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 particles)

The blending amount shown in Table 1 (unit: parts by mass) of epoxy resin, hardener, polymer component, flux, inorganic filler, and organic filler are set to NV value ([Drying coating composition quality]/[Before drying The mass of paint components]×100) was added to the organic solvent (methyl ethyl ketone) so that it became 60%. Then, add Φ 1.0 mm beads and Φ 2.0 mm beads with the same quality as the solid components (epoxy resin, hardener, flux, polymer components, inorganic fillers, and organic fillers), and use a bead mill (Japan It is made by Fritsch Japan Co., Ltd., planetary micro pulverizer P-7) and stirred for 30 minutes. After stirring, the beads were removed by filtration to produce a varnish containing the first adhesive.

Use a small precision coating device (manufactured by Lianjing Seiki Co., Ltd.) to apply the obtained varnish to the base film (manufactured by Teijin DuPont Film Co., Ltd., trade name "Purex (Purex) A54") On the surface, use a clean oven (manufactured by ESPEC Co., Ltd.) to dry (80℃/10 min) to obtain the single-layer film (A-1) and single-layer film (A- 2) Single-layer film (A-3), single-layer film (A-4) and 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]

<Preparation of a single-layer film including a layer not containing a flux> The compounds used in the preparation of a single-layer film including a layer not containing a flux are shown below.

(A) (Meth) acrylic compound · Acrylic ester with a chlorophyll-type skeleton (Osaka Gas Chemical Co., Ltd., EA-0200, difunctional group) · Acrylic ester with a bisphenol A-type skeleton (Shin Nakamura Chemical Industry Co., Ltd. Company, EA-1020) ・Ethoxylated isocyanuric acid triacrylate (Shin Nakamura Chemical Industry Co., Ltd., A-9300)

(B) Thermal free radical generators · Dicumyl peroxide (NOF Corporation, Percumyl (registered trademark) D) · Di-tertiary butyl peroxide (NOF Corporation, Perbutyl (registered trademark) D) ・1,4-bis-((tertiary butylperoxy)diisopropyl)benzene (NOF Corporation, Perbutyl) (registered trademark) P )

(C) Macromolecular component · Acrylic resin (Hitachi Chemical Co., Ltd., KH-CT-865, weight average molecular weight Mw: 100,000, Tg: 10°C) · Urethane resin (Diison Covestro polymer ( DIC Covestro Polymer Co., Ltd., Lycra (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, the polymer component, the inorganic filler, and the organic filler of the compounding amount shown in Table 2 (unit: parts by mass) are added to the organic solvent (methyl ethyl ketone) so that the NV value becomes 60% middle. Then, add Φ 1.0 mm beads and Φ 2.0 mm beads with the same mass as the solid components ((meth)acrylic compound, polymer component, inorganic filler, and organic filler), and use a bead mill (Japan Fritz (Fritsch Japan) Co., Ltd., planetary micro 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 stirred and mixed to produce a varnish containing a second adhesive.

Use a small precision coating device (Lai Seiki) to apply the obtained coating varnish to the base film (manufactured by Teijin DuPont Film Co., Ltd., trade name "Purex (Purex) A54"). Drying (80℃/10 min) in an oven (manufactured by ESPEC Co., Ltd.) to obtain the monolayer film (B-1), monolayer film (B-2), and monolayer film (B-2) 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 layer containing no flux in the single-layer film (B-1) to the single-layer film (B-7) was set to 20 μm.

[Table 2]

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

<Evaluation 1> (Measurement of the lowest melt viscosity) A rotary rheometer (manufactured by TA Instruments, trade name: ARES-G2) was used to measure the first, second, and film-like adhesives ( The melt viscosity of a laminate of a layer containing a flux and a layer not containing a flux). The evaluation sample of the melt viscosity of the film adhesive was prepared in the following procedure. First, two of the single-layer films (the first film and the second film) produced above were laminated at 50°C to produce a double-layer film with a total thickness of 40 μm. The combination of single-layer films was set as shown in Table 3 and Table 4. This double-layer film was cut, and the cut double-layer films were laminated on each other to produce a four-layer film (laminated film) with a total thickness of 80 μm. The cutting of the laminated film and the lamination of the cut laminated film were repeated in the same order to prepare an evaluation sample with 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～4000 Pa･s (measured at 130℃), and the minimum melt viscosity of the second adhesive is 1000 Pa･s～3000 Pa･s (at 120℃) Measured value), the minimum melt viscosity of the film adhesive is 1500 Pa･s～3500 Pa･s (measured value at 130°C).

<Evaluation 2> The film adhesive obtained in the examples and comparative examples and the semiconductor device produced using the film adhesive were evaluated for initial connectivity, porosity, and solder wettability using the methods shown below , Exudation amount measurement, and insulation reliability evaluation. The results are shown in Table 3 and Table 4.

(Evaluation of initial connectivity) The film-like adhesive prepared in the examples or comparative examples was cut to a predetermined size (length 8 mm × width 8 mm × thickness 40 μm), and the base film excluding the adhesive layer was peeled off . Laminated on a semiconductor wafer with solder bumps (wafer size: length 7.3 mm × width 7.3 mm × thickness 0.15 mm, bump height: the total height of the copper pillar and the height of the solder is about 40 μm, bump Number: 328). The substrate film with the adhesive layer is peeled off, and the laminated chip is packaged with the flux-containing layer facing downward using the flip chip packaging device "FCB3" (manufactured by Panasonic Co., Ltd., trade name) On a glass epoxy substrate with copper wiring (thickness of glass epoxy substrate: 420 μm, thickness of copper wiring: 9 μm) (Packaging conditions: crimping temperature 350°C, crimping time 3 seconds, crimping pressure 0.5 MPa). Thereby, a semiconductor device A in which the glass epoxy substrate and the semiconductor wafer with solder bumps are connected via a daisy chain is produced in the same manner as in (a) to (c) of FIG. 4.

A multimeter (manufactured by ADVANTEST Co., Ltd., trade name "R6871E") was used to measure the connection resistance value of the obtained semiconductor device A to evaluate the initial conduction after packaging. When the connection resistance value is 10.0 Ω or more and 12.5 Ω or less, it is evaluated as connectivity "A" (good), and when the connection resistance value is greater than 12.5 Ω and 13.5 Ω or less, it is evaluated as connectivity "B" (bad). The connection resistance value is greater than 13.5 Ω and 20 Ω or less is evaluated as the connectivity "C" (poor), the connection resistance value is greater than 20 Ω, the connection resistance value is less than 10 Ω, and the connection is not due to poor connection. All cases where the resistance value is displayed are evaluated as connectivity "D" (bad).

(Porosity evaluation) The appearance of the semiconductor device A manufactured by the above method was taken using an ultrasonic imaging diagnostic device (trade name "Insight-300", manufactured by Insight Co., Ltd.) Image, and use the scanner GT-9300UF (made by Seiko Epson Co., Ltd., trade name) to introduce the image of the adhesive layer (the layer containing the cured product of the film-like adhesive for semiconductors) on the wafer, and use The image processing software Adobe Photoshop (registered trademark) recognizes the pores by color correction and two-gray gradation, and calculates the proportion of the pores by the histogram. The area of the adhesive portion on the wafer is set to 100%, the case where the porosity generation rate is 3% or less is evaluated as "AA" (good), and the case where the porosity generation rate is more than 3% and less than 5% is evaluated as In "A" (good), the case where the porosity generation rate was more than 5% and 10% or less was evaluated as "B" (poor), and the case where the porosity generation rate was more than 10% was evaluated as "C" (poor).

(Evaluation of solder wettability) Regarding the semiconductor device A manufactured by the above method, the cross section of the connection portion was observed, and the case where the solder wettability on the upper surface of the Cu wiring was 100% to 50% was evaluated as "A "(Good), the case where the solder wettability is 50% to 0% is evaluated as "B" (bad), and the case where solder scattering occurs is evaluated as "C" (bad).

(Measurement of Bleeding Amount) Using a metal microscope (manufactured by Keyence Co., Ltd.), the semiconductor device A manufactured by the above method was observed from the upper surface of the device, and the measurement was measured from the periphery of the semiconductor wafer (four sides). ) The amount of the cured product derived from the film-like adhesive that oozes (the width of the oozing part). The measurement is performed on each side of the semiconductor device, and the average value of the four sides is calculated as the bleeding amount.

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

(Insulation reliability test B [HAST test: Highly Accelerated Storage Test]) The film-like adhesive (thickness: 40 μm) produced in the Examples or Comparative Examples was attached to the comb-shaped electrode to evaluate TEG (Hitachi Chemical Co., Ltd., wiring pitch: 50 μm), using flip chip packaging device "FCB3" (Panasonic (Panasonic) Co., Ltd., trade name), from the top of the semiconductor chip with solder bumps (chip Dimensions: length 7.3 mm × width 7.3 mm × thickness 0.15 mm, bump height: the total 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 State to be packaged (under the package conditions: crimping temperature of 180°C, crimping time of 3 seconds, and crimping pressure of 0.5 MPa, after thermo-compression bonding (gelation step of the adhesive), the temperature of the crimping joint is raised to 260°C, And continuously perform thermo-compression bonding at a crimping joint temperature of 260°C, a crimping time of 3 seconds, and a crimping pressure of 0.5 MPa). Thus, the semiconductor device C is obtained. The crimped semiconductor device C was cured in a clean oven (manufactured by ESPEC Co., Ltd.) at 175°C for two hours, and the cured sample was set in an accelerated life test device (Hirayama Manufacturing Co., Ltd.) Manufacture, trade name "PL-422R8", conditions: 130°C/85%RH/100 hours, 5 V applied), the insulation resistance was measured. If the insulation resistance after 100 hours is 10 ⁸ Ω or more is evaluated as "A", if it is 10 ⁷ Ω or more and less than 10 ⁸ Ω, it is evaluated as "B", and if it is less than 10 ⁷ Ω, it is evaluated as "A". "C".

[table 3]

[Table 4]

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

10‧‧‧Semiconductor chip 15‧‧‧Wiring (connection part) 20‧‧‧Substrate (wiring circuit board) 30‧‧‧Connection bump 32‧‧‧Bump (connection part) 34‧‧‧Through electrode 40‧ ‧‧Seal part 40a‧‧‧Upper part 40b‧‧‧Lower part 41‧‧‧Semiconductor film adhesive (film adhesive) 41a‧‧‧The first layer 41b‧‧‧The second layer 50‧‧‧ Interposer 60‧‧‧Solder resist 100, 200, 300, 400, 500, 600‧‧‧Semiconductor device

1(a) and 1(b) are schematic cross-sectional views showing an embodiment of the semiconductor device of the present invention.

2(a) and 2(b) are schematic cross-sectional views showing another embodiment of the semiconductor device of the present invention.

Fig. 3 is a schematic cross-sectional view showing another embodiment of the semiconductor device of the present invention.

4(a) to 4(c) are step cross-sectional views schematically showing one embodiment of a method of manufacturing a semiconductor device of the present invention.

10‧‧‧Semiconductor chip

15‧‧‧Wiring (connection part)

20‧‧‧Board (wiring circuit board)

30‧‧‧Connecting bump

40‧‧‧Sealing part

40a‧‧‧Upper part

40b‧‧‧Lower part

100‧‧‧Semiconductor device

Claims (13)

A film-like adhesive for semiconductors, comprising: a first layer containing a first thermosetting adhesive, the first thermosetting adhesive containing a flux compound; and a first layer provided on the first layer and containing a second layer The second layer of the thermosetting adhesive, the second thermosetting adhesive does not substantially contain a flux compound, and 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 1 or more. The film-like adhesive for semiconductors described in the first item of the scope of patent application, wherein the curing reaction rate of the second thermosetting adhesive after being held at 200° C. for 5 seconds is 80% or more. The film-like adhesive for semiconductors as described in claim 1 or 2, wherein the second thermosetting adhesive contains a radical polymerizable compound and a thermal radical generator. The film-like adhesive for semiconductors as described in the third item of the scope of patent application, wherein the thermal radical generator is a peroxide. The film-like adhesive for semiconductors described in claim 3, wherein the radically polymerizable compound is a (meth)acrylic compound. The film-like adhesive for semiconductors as described in claim 5, wherein the (meth)acrylic compound has a turbidity skeleton. The film-like adhesive for semiconductors as described in item 1 or item 2 of the scope of patent application, wherein the flux compound has a carboxyl group. The film adhesive for semiconductors as described in item 1 or item 2 of the scope of patent application, wherein the flux compound has two or more carboxyl groups. The film-like adhesive for semiconductors as described in item 1 or item 2 of the scope of patent application, wherein the melting point of the flux compound is 150° C. or less. The film-like adhesive for semiconductors as described in claim 1 or 2, wherein the first thermosetting adhesive contains a curing agent. The film-like adhesive for semiconductors as described in claim 10, wherein the curing agent is an imidazole-based curing agent. A method of manufacturing a semiconductor device, which is a semiconductor device in which the respective connecting portions of a semiconductor wafer and a wiring circuit board are electrically connected to each other, or a method of manufacturing a semiconductor device in which the respective connecting portions of a plurality of semiconductor wafers are electrically connected to each other, the semiconductor The method of manufacturing the device includes a step of sealing at least a part of the connection portion using the film-like adhesive for semiconductors as described in any one of the claims 1 to 11 in the scope of the application. A semiconductor device is a semiconductor device in which the respective connection portions of a semiconductor wafer and a wiring circuit board are electrically connected to each other, or a semiconductor device in which respective connection portions of a plurality of semiconductor wafers are electrically connected to each other, at least a part of the connection portion is Items 1 to 11 of the scope of patent application The cured product of the film-like adhesive for semiconductors as described in any one is sealed.

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