TWI804062B - Film adhesive for semiconductor, method for manufacturing semiconductor device, and semiconductor device - Google Patents

Abstract

The film-like adhesive for semiconductors of the present invention includes: a first layer comprising a first thermosetting adhesive containing a flux compound; A second layer of a curable adhesive, wherein 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 for manufacturing a semiconductor device, and a semiconductor device.

Conventionally, when connecting a semiconductor chip (chip) and 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 functionality, high integration, and high speed of semiconductor devices, conductive protrusions 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, for the connection between semiconductor wafers and substrates, Chip On Board (COB) type connections are popularly used in Ball Grid Array (BGA), Chip Size Package (CSP), etc. The method is also equivalent to the FC connection method. In addition, the FC connection method is also widely used as a chip-on-chip (COC) type connection method in which connection parts (for example, bumps and wiring) are formed on semiconductor chips to connect semiconductor chips.

In addition, in packages that strongly require further miniaturization, thinning, and high functionality, chip stack packages and Package On Package (Package On Package) packages that use the above-mentioned connection method to laminate and multi-stage chips , POP), Through-Silicon Via (TSV), etc. have also begun to be widely used. This build-up and multi-stage technology three-dimensionally arranges semiconductor wafers, etc., so it is possible to reduce the size of the package compared to the method of two-dimensional arrangement. In addition, it is also effective in improving the performance of semiconductors, reducing noise, reducing package area, and saving power, so it is attracting attention as a next-generation semiconductor wiring technology.

In addition, in general, metal bonding has been used from the viewpoint of ensuring sufficient connection reliability (for example, insulation reliability) in connection between connection parts. As the main metals used in the connection parts (for example, bumps and wirings), there are solder, tin, gold, silver, copper, nickel, and the like, and conductive materials including a plurality of these are also used. The surface of the metal used in the connection part is oxidized 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 part. If such impurities remain, the connection reliability (for example, insulation reliability) between the semiconductor wafer and the substrate or between two semiconductor wafers may be lowered, thereby impairing the advantages of the connection method described above.

In addition, as a method of suppressing the generation of these impurities, there is a method of coating the connection portion with an anti-oxidation film known in Organic Solderability Preservatives (OSP) treatment, etc., but the anti-oxidation The film may cause a decrease in solder wettability, a decrease in connectivity, and the like during a connection process.

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

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

[Problem to be Solved by the Invention] In addition, flip-chip packaging has further developed towards higher functionality and higher integration in recent years. With higher functionality and higher integration, the pitch between wirings becomes narrower, and connection reliability tends to decrease.

In addition, in recent years, from the viewpoint of improving productivity, it is required to shorten the pressure-bonding time at the time of assembly of the flip-chip package. When the crimping time is shortened, if the film-like adhesive for semiconductors is not sufficiently hardened during crimping, the connection portion cannot be sufficiently protected, and connection failure occurs when the crimping pressure is released. Furthermore, when solder is used for the connecting portion, if the film-like adhesive for semiconductors is not sufficiently hardened in a temperature range lower than the melting temperature of the solder during crimping, solder will be generated when the temperature at the time of crimping reaches the melting temperature of the solder. Poor connection due to scattering and flow. On the other hand, when the film-like adhesive for semiconductors hardens before the connection parts come into contact with each other by crimping, the adhesive intervenes between the connection parts and poor connection occurs.

Then, an object of this invention is to provide the film-form adhesive agent for semiconductors which can acquire excellent connection reliability even when making pressure-bonding time short. Moreover, the object of this invention is to provide the semiconductor device which uses such a film-form adhesive agent for semiconductors, and its manufacturing method. [Means to solve the problem]

The film-like adhesive for semiconductors of the present invention includes: a first layer comprising a first thermosetting adhesive containing a flux compound; A second layer of a curable adhesive, wherein the second thermosetting adhesive does not substantially contain a flux compound.

According to the film-form adhesive for semiconductors of the present invention, the second layer is less susceptible to the influence of the flux compound, and thus exhibits the characteristic of being quickly and sufficiently hardened after the connection parts contact each other via the second layer. In addition, with regard to the film-like adhesive described in Patent Document 2, the thermoplastic resin is likely to be softened at high temperature during pressure bonding to 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-form adhesive agent for semiconductors of this invention. For these reasons, according to the film-form adhesive agent for semiconductors of this invention, even when it press-bonds at high temperature and in a short time, excellent connection reliability (for example, insulation reliability) can be acquired. Moreover, according to the film-form adhesive agent for semiconductors of this invention, since the shortening of pressure-bonding time can be achieved, productivity can be improved. Moreover, according to the film-form adhesive agent for semiconductors of this invention, flip-chip packaging can be made high in functionality and high in volume easily.

In addition, conventional adhesives for semiconductors (for example, the film-like adhesive described in Patent Document 1) are subjected to high-temperature pressure-bonding in a state where the adhesive for semiconductors is not sufficiently cured when the pressure-bonding time is shortened. Voids may be generated, and delamination may occur inside the package starting from the voids. If the peeling inside the package becomes large, stress will act on the connection portion to cause cracks, so the peeling inside the package will cause poor connection of the package. On the other hand, according to the film-form adhesive agent for semiconductors of this invention, since it can fully harden in a short time, generation|occurrence|production of a void can be suppressed easily. 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 rapidly, so even if microvoids are generated, the expansion of the voids is suppressed, and it is difficult to generate visible cracks. sized pores. These circumstances can be said to be one of the reasons for obtaining excellent adhesion reliability by the film-form adhesive agent of this invention.

In addition, when a flip-chip package is manufactured using a conventional film-like adhesive, the adhesive may bleed out from the periphery of the chip because the adhesive has not hardened in a short time. Such bleeding of the adhesive prevents the mounting of adjacent chips, resulting in a decrease in the number of packages that can be mounted per one wafer. That is, if bleeding of the adhesive from the periphery of the wafer occurs, productivity will decrease. In addition, if the amount of adhesive seeping out is excessive, the seeping adhesive may spread to the mounted wafer, which may cause damage to the mounted chip when another chip is further mounted on the wafer. On the other hand, according to the film-form adhesive agent for semiconductors of this invention, since it can fully harden in a short time, generation|occurrence|production of the bleeding of the said adhesive agent can be suppressed.

Moreover, in recent years, solder, copper, etc. tend to be used instead of gold etc. which are hard to corrode, for the purpose of cost reduction as the metal of a connection part. Furthermore, for 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, etc. which are not easily corroded, and to perform treatments such as OSP (Organic Solderability Preservative) treatment. In the flip-chip package, in addition to narrowing the pitch and increasing the number of pins, the cost reduction is also being promoted, so there is a tendency to use a metal that is easily corroded and lowers the insulation, and the insulation reliability tends to decrease. On the other hand, according to the film-form adhesive agent for semiconductors of this invention, the fall of the insulation reliability with respect to the said metal can be suppressed.

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

The second thermosetting adhesive preferably contains a radical polymerizable compound and a thermal radical generator. In this case, since the hardening rate is very excellent, even if it press-bonds at a high temperature and for a short time, it is hard to generate|occur|produce a void, and can obtain more excellent connection reliability.

The thermal radical generating agent is preferably a peroxide. In this case, further excellent operability and storage stability can be obtained, and thus further excellent connection reliability can be easily obtained.

The radically polymerizable compound is preferably a (meth)acrylic compound. In this case, further excellent connection reliability can be easily obtained.

The (meth)acrylic compound preferably has a terpene-type skeleton. In this case, further excellent connection reliability can be easily obtained.

The flux compound preferably has a carboxyl group, more preferably has two or more carboxyl groups. In this case, further excellent connection reliability can be easily obtained.

[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, further excellent connection reliability can be easily obtained. [chemical 1]

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

The melting point of the flux compound is preferably 150°C or lower. In this case, since the flux is melted before the adhesive hardens during thermocompression bonding, and oxide films such as solder are reduced and removed, further excellent connection reliability can be easily obtained.

The first thermosetting adhesive preferably contains a curing agent, more preferably an imidazole-based curing agent. In this case, more excellent connection reliability can be easily obtained.

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

The semiconductor device of the present invention is a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other, wherein at least a part of the connection portion is provided by the Semiconductors are sealed with hardened film adhesives. The semiconductor device is excellent in connection reliability (for example, insulation reliability). [Effect of the invention]

According to this invention, the film-form adhesive agent for semiconductors which can obtain excellent connection reliability even when making pressure-bonding time short. Moreover, according to this invention, the semiconductor device using such a film-form adhesive agent for semiconductors, and its manufacturing method can be provided.

In this specification, "(meth)acrylate" means at least one of acrylate and its corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryl" and "(meth)acryl". In addition, the numerical range represented by "-" shows the range which includes the numerical value described before and after "-" as a minimum value and a maximum value, respectively.

Hereinafter, preferred embodiments of the present invention will be described in detail while referring to the drawings as the case may be. In addition, in the drawings, the same symbols are assigned to the same or corresponding parts, and repeated explanations are omitted. In addition, positional relationships such as up, down, left, and right are assumed to be based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios in the drawings are not limited to the ratios shown in the drawings.

＜Film Adhesives for Semiconductors＞ The film-like adhesive for semiconductors according to this embodiment includes: a first layer (flux-containing layer) including a first thermosetting adhesive containing a flux compound (hereinafter also simply referred to as "first adhesive"); A second layer (flux-free layer) that is provided on the first layer and includes a second thermosetting adhesive that does not substantially contain a flux compound (hereinafter also simply referred to as “second adhesive”).

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

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

(1st Adhesive) The first adhesive contains, for example, a thermosetting component and a flux compound. As a thermosetting component, a thermosetting resin, a curing agent, etc. are mentioned. Examples of thermosetting resins include epoxy resins, phenol resins (excluding those contained as hardeners), polyimide resins, and the like. Among these, the thermosetting resin is preferably an epoxy resin. Moreover, the film-form adhesive agent for semiconductors of this embodiment may contain the polymer component and filler whose weight average molecular weight is 10000 or more as needed.

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

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

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

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

[(b) Component: Hardener] Examples of the component (b) include phenol resin-based curing agents, acid anhydride-based curing agents, amine-based curing agents, imidazole-based curing agents, and phosphine-based curing agents. When the component (b) contains phenolic hydroxyl groups, acid anhydrides, amines, or imidazoles, it exhibits flux activity that suppresses the formation of an oxide film in the joint, thereby improving connection reliability and insulation reliability. Each curing agent will be described below.

(i) Phenolic resin hardener The phenolic resin-based hardener is not particularly limited as long as it has two or more phenolic hydroxyl groups in the molecule. For example, phenol novolak resin, cresol novolac resin, phenol aralkyl resin, cresol Naphthol formaldehyde polycondensate, triphenylmethane type multifunctional phenolic resin and various multifunctional phenolic resins. These may 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 phenolic resin-based curing agent to the component (a) (number of moles of phenolic hydroxyl groups possessed by the phenolic resin-based curing agent/ (a) The molar number of the epoxy group which the component has) Preferably it is 0.3-1.5, More preferably, it is 0.4-1.0, More preferably, it is 0.5-1.0. If the equivalent ratio is 0.3 or more, the hardening property tends to be improved and the adhesive force tends to be improved. If it is 1.5 or less, unreacted phenolic hydroxyl groups will not remain excessively, the water absorption is suppressed to a low value, and the insulation reliability is improved. Propensity.

(ii) Acid anhydride hardener As an acid anhydride hardener, for example, methylcyclohexanetetracarboxylic dianhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic dianhydride, and ethylene glycol bis-trimellitic anhydride can be used. ester. These may 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 curing agent to the component (a) (the number of moles of the acid anhydride groups in the acid anhydride curing agent/(a) 0.3-1.5 are preferable, and the molar number of the epoxy group which a component has is more preferable, and it is more preferable that it is 0.4-1.0, and it is still more preferable that it is 0.5-1.0. If the equivalent ratio is 0.3 or more, the hardening property tends to be improved and the adhesive force 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 hardener As the amine-based curing agent, for example, dicyandiamide can be used.

From the viewpoint of good curability, adhesiveness, and storage stability, the equivalent ratio of the amine-based hardener to the component (a) (the number of moles of active hydroxyl groups in the amine-based hardener/(a) 0.3-1.5 are preferable, and the molar number of the epoxy group which a component has is more preferable, and it is more preferable that it is 0.4-1.0, and it is still more preferable that it is 0.5-1.0. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive force tends to be improved, and when it is 1.5 or less, unreacted amine does not remain excessively, and the insulation reliability tends to be improved.

(iv) Imidazole hardener Examples of imidazole hardeners include: 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1 -cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl Base-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4- Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'- Methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine iso Cyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxy Methylimidazole, and adducts of epoxy resins and imidazoles. Among these, 1-cyanoethyl-2-undecylimidazole and 1-cyano-2-phenylimidazole are preferable from the viewpoint of excellent curability, storage stability, and connection reliability. , 1-cyanoethyl-2-undecylimidazolium 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 individually or in combination of 2 or more types. In addition, it can also be used as a latent curing agent obtained by microencapsulating these.

The content of the imidazole-based curing agent is preferably from 0.1 to 20 parts by mass with respect to 100 parts by mass of the component (a), more preferably from 0.1 to 10 parts by mass. When content of an imidazole type hardening agent is 0.1 mass part or more, it exists in the tendency for curability to improve. In addition, when the content of the imidazole-based curing agent is 20 parts by mass or less, the fluidity of the first adhesive agent during crimping can be ensured, and the first adhesive agent between the connection parts can be sufficiently eliminated. As a result, hardening of the first adhesive in a state interposed between the solder and the connection portion can be suppressed, so connection failure is less likely to occur.

(v) Phosphine hardener Examples of phosphine-based hardeners include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetrakis(4-methylphenyl)borate, and tetraphenylphosphonium (4-fluorophenyl) base) borate.

The content of the phosphine-based curing agent is preferably from 0.1 to 10 parts by mass, more preferably from 0.1 to 5 parts by mass, based on 100 parts by mass of the component (a). When the content of the phosphine curing 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 does not harden before the metal joint is formed, and poor connection is less likely to occur.

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

When the first adhesive contains a phenolic 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 an oxide film and can further improve connection reliability.

[(c) Component: flux compound] The component (c) is a compound having flux activity, and functions as a flux in the first adhesive. As the component (c), a known flux compound can be used without particular limitation as long as it reduces and removes an oxide film on the surface of solder or the like to facilitate metal bonding. 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 hardening|curing agent which is (b) component is not contained in (c) component.

The flux compound preferably has a carboxyl group, and more preferably has two or more carboxyl groups, from the viewpoint of obtaining sufficient flux activity and more excellent connection reliability. Among them, compounds having two carboxyl groups are preferred. Compounds with two carboxyl groups are less volatile than compounds with one carboxyl group (monocarboxylic acid) even at high temperatures during connection, and can further suppress the generation of pores. In addition, when a compound having two carboxyl groups is used, compared with the case of using a compound having three or more carboxyl groups, the viscosity increase of the film adhesive for semiconductors during storage and connection work can be further suppressed, and the 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. [Chem 2]

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

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

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 acid has been used as a flux compound, but the inventors of the present invention think that, in the conventional flux compound, the decrease in adhesive force occurs for the following reason.

Usually, the epoxy resin reacts with a curing agent to perform a curing reaction, but in this case, a carboxylic acid as a flux compound is included in the curing 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. This ester bond is easily hydrolyzed by moisture absorption, etc., and the decomposition of this ester bond is considered to be one cause of the fall of the adhesive force after moisture absorption.

On the other hand, among the compounds having a ^group represented by the formula (1), the first adhesive contains a compound having a group in which R is an electron-donating group, that is, a compound having a carboxyl group having an electron-donating group nearby. In the case of , the flux activity is sufficiently obtained by the carboxyl group, and even when the ester bond is formed, the electron density of the ester bond part is increased by the electron-donating group, and the decomposition of the ester bond is suppressed. . In addition, it is considered that since the substituent (electron-donating group) exists near the carboxyl group, the reaction between the carboxyl group and the epoxy resin is suppressed due to steric hindrance, making it difficult to generate 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), R ¹ is an electron-donating group, it is difficult to produce a composition due to moisture absorption, etc. Changes, can maintain excellent adhesion. In addition, the above-mentioned action can also make the hardening reaction between the epoxy resin and the hardener less likely to be hindered by the flux compound, and this action can also expect reliable connection due to the sufficient progress of the hardening reaction between the epoxy resin and the hardener. sex-enhancing effect.

When 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, when 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.

As an electron donating group, an alkyl group, a hydroxyl group, an amino group, an alkoxy group, and an alkylamine group are mentioned, for example. The electron-donating group is preferably a group that does not easily react with other components (for example, the epoxy resin of (a) component), specifically, it is preferably an alkyl group, a hydroxyl group, or an alkoxy group, and more preferably an alkyl group .

The alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms. The larger the carbon number of the alkyl group, the larger the electron donating property and steric hindrance tend to be. An alkyl group having a carbon number within the above-mentioned range is excellent in balance between electron donating properties and steric hindrance, and therefore, the effect of the present invention can be exhibited more remarkably according to the alkyl group.

In addition, the alkyl group may be linear or branched, and is preferably linear. When the alkyl group is linear, the number of carbon atoms in the alkyl group is preferably not more than the number of carbon atoms in the main chain of the flux compound from the viewpoint of the balance between electron donating properties 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, more preferably an alkoxy group having 1 to 5 carbon atoms. There is a tendency that the electron-donating property and steric hindrance increase as the number of carbon atoms in the alkoxy group increases. An alkoxy group having a carbon number within the above-mentioned range is excellent in balance between electron donating properties and steric hindrance, and therefore, the effect of the present invention can be exhibited more remarkably according to the alkoxy group.

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 number of carbon atoms in the alkoxy group is preferably not more than the number of carbon atoms in the main chain of the flux compound from the viewpoint of the balance between electron donating properties 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 straight-chain alkoxy group, the number of carbon atoms in the alkoxy group is preferably that of the main chain of the flux compound. Carbon number (n+1) or less.

As an alkylamine group, a monoalkylamine group and a dialkylamine group are mentioned. The monoalkylamino group is preferably a monoalkylalkyl group having 1 to 10 carbon atoms, more preferably a monoalkylamino group having 1 to 5 carbon atoms. The alkyl portion of the monoalkylamino group may be linear or branched, preferably linear.

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

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

[Chem 3]

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

R ¹ has the same meaning as R ¹ in formula (1). 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 formula (1), R ¹ in formula (2) is preferably an electron-donating group.

n in the formula (2) is preferably 1 or more. When n is 1 or more, compared with the case where n is 0, the flux compound is less likely to volatilize due to the high temperature at the time of connection, and 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. When n is 15 or less, further excellent connection reliability can be obtained.

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

[chemical 4]

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

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

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

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

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

The melting point of the flux compound is preferably not higher than 150°C, more preferably not higher than 140°C, further preferably not higher than 130°C. Such a flux compound tends to exhibit sufficient flux activity before the hardening reaction of the epoxy resin and the hardener occurs. Therefore, according to the semiconductor film adhesive using the first adhesive containing such a flux compound, a semiconductor device having further 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 variation in temperature within the sample. As a container for the sample, a capillary tube with one end closed is often used, but depending on the measurement device, a container is sandwiched between two microscope cover glasses. In addition, if the temperature is raised rapidly, a temperature gradient will be generated between the sample and the thermometer, and measurement errors will occur. Therefore, it is ideal to measure the heating at the time of measuring the melting point at a rate of increase of 1°C per minute or less. .

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 in the surface. Usually, the temperature at which the appearance of the sample starts 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 measurement devices, but the most typical device uses a device in which a capillary tube filled with a sample is attached to a double-tube thermometer and heated in a warm bath. In order to attach the capillary to the double-tube thermometer, a highly viscous liquid is used as the bath liquid. In many cases, concentrated sulfuric acid or silicone oil is used, and the sample is installed so that the sample moves to the vicinity of the reservoir at the tip of the thermometer. . In addition, as the melting point measuring device, a device that heats using a metal heat block, adjusts the heating while measuring the light transmittance, and automatically determines the melting point may be used.

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

Based on the total mass of the first adhesive, the content of the component (c) is preferably from 0.5% by mass to 10% by mass, more preferably from 0.5% by mass to 5% by mass.

[(d) component: polymer component with a weight average molecular weight of 10,000 or more] The 1st adhesive agent may contain the polymer component ((d) component) whose weight average molecular weight is 10000 or more as needed. The heat resistance and film formability of the 1st adhesive agent containing (d) component are more excellent.

Examples of the component (d) include phenoxy resins, polyimide resins, polyamide resins, polycarbodiimide resins, cyanate resins, acrylic resins, polyester resins, polyethylene resins, Polyether resin, polyetherimide resin, polyvinyl acetal resin, urethane resin and acrylic rubber. Among these, from the viewpoint of excellent heat resistance and film formability, phenoxy resins, polyimide resins, urethane resins, acrylic rubbers, cyanate resins, and polycarbonate resins are preferable. The imide resin is more preferably phenoxy resin, polyimide resin, urethane resin and acrylic rubber, more preferably phenoxy resin, urethane resin and acrylic rubber. These (d) components can also be used individually or as a mixture or copolymer of 2 or more types. However, the compound corresponding to (a) component and the compound corresponding to (e) component are not included in (d) component.

(d) The weight average molecular weight of a component is 10000 or more, for example, Preferably it is 20000 or more, More preferably, it is 30000 or more. According to such (d) component, the heat resistance and film formability of a 1st adhesive agent can be improved further. (d) The weight average molecular weight of the component is preferably at most 200,000, more preferably at most 100,000. According to such (d) component, the heat resistance of a 1st adhesive agent can be improved further. 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 weight average molecular weight means the weight average molecular weight when it measures in terms of polystyrene using the high performance liquid chromatography (manufactured by Shimadzu Corporation, trade name: C-R4A) . For the measurement, for example, the following conditions can be used. Detector: LV4000 Ultraviolet (UV) Detector (Detector) (manufactured by Hitachi, Ltd., trade name) Pump: L6000 pump (Pump) (manufactured by Hitachi, Ltd., trade name) Column: Gelpack GL-S300MDT-5 (2 pieces in total) (manufactured by Hitachi Chemical Co., Ltd., trade name) Eluent: tetrahydrofuran (tetrahydrofuran, THF) / dimethyl formamide (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 the component (d), the ratio C _a /C _d (mass ratio) of the content C _a of the component (a) to the content C _d of the component (d) is preferably 0.01 to 5, more preferably It is 0.05-3, More preferably, it is 0.1-2. When the ratio C _a /C _d is 0.01 or more, better curability and adhesive force can be obtained, and when the ratio C _a /C _d is 5 or less, better film formability can be obtained.

[(e) Ingredient: Filler] The 1st adhesive agent may contain a filler ((e) component) as needed. The viscosity of the first adhesive, the physical properties of the cured product of the first adhesive, and the like can be controlled by the component (e). Specifically, according to the component (e), for example, generation of voids at the time of connection can be suppressed, the moisture absorption rate of the cured product of the first adhesive agent can be reduced, and the like.

As (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, preferred ones are selected from silicon dioxide, aluminum oxide, titanium oxide, and boron nitride. At least one selected from the group consisting of, 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 whiskers include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, boron nitride, and the like. As an organic filler, resin filler (resin particle) is mentioned, for example. Examples of the resin filler include polyurethane, polyimide, and the like. 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 are also effective in improving film formability because they can impart flexibility.

From the viewpoint that it is easy to adjust the modulus of elasticity to a desired range, and the generation of voids can be more sufficiently reduced while suppressing warpage, and thus excellent connection reliability can be obtained, the component (e) Based on the total mass, the content of the inorganic filler may be more than 50 mass%, more than 70 mass%, or more than 80 mass%. The content of the inorganic filler may be 100% by mass or less or 90% by mass or less.

From the viewpoint of better insulation reliability, the component (e) is preferably insulating (is an insulating filler). The first adhesive agent 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 that it is easy to adjust the modulus of elasticity to a desired range, and the generation of voids can be more sufficiently reduced while suppressing warpage, 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 contain only an insulating filler substantially. That is, (e) component does not have to contain a conductive filler substantially. "Not containing substantially" means that the content of the conductive filler in (e) component is less than 0.5% by mass based on the total mass of (e) component.

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

In terms of ease of surface treatment, the surface treatment is preferably silane treatment using silane compounds such as epoxy silane, amino silane, and acrylic silane. From the viewpoint of excellent dispersibility, fluidity, and adhesive force, the surface treatment agent is preferably selected from the group consisting of glycidyl-based compounds, phenylamine-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 the component (e) is preferably 1.5 μm or less from the viewpoint of preventing jamming during flip-chip bonding, and more preferably 1.0 μm or less from the viewpoint of excellent visibility (transparency) .

From the viewpoint of suppressing the decrease in heat dissipation, easily suppressing the generation of voids, increasing the moisture absorption rate, etc., the content of the component (e) is preferably 15% by mass or more based on the total mass of the first adhesive , more preferably at least 20% by mass, further preferably at least 40% by mass. Based on the total mass of the first adhesive, it is easy to suppress the decrease in the fluidity of the first adhesive due to the increase in viscosity and the occurrence of trapping of the filler to the connection part, and it is easy to suppress the decrease in connection reliability. , The content of the component (e) is preferably at most 90% by mass, more preferably at most 80% by mass. From these viewpoints, based on the total mass of the first adhesive, the content of the component (e) is preferably from 15% by mass to 90% by mass, more preferably from 20% by mass to 80% by mass, and still more preferably 40% by mass to 80% by mass.

[other ingredients] Additives such as antioxidants, silane coupling agents, titanium coupling agents, leveling agents, and ion-scavenging agents can also be formulated in the first adhesive. These can be used individually by 1 type or in combination of 2 or more types. What is necessary is just to adjust suitably so that the effect of each additive may express about the compounding quantity of these.

From the viewpoint of reliability, the minimum melt viscosity of the first adhesive is preferably at least 1000 Pa･s, more preferably at least 1500 Pa･s, further preferably at least 2000 Pa･s. When the minimum melt viscosity is 1000 Pa･s or more, the thermal expansion of voids involved during packaging is suppressed, and the possibility of peeling during long-term use (such as a reliability test) is reduced. On the other hand, the minimum melt viscosity of the first adhesive is preferably 10,000 Pa･s or less in terms of sufficiently removing the first layer during solder connection to reduce resin sticking and thus excellent electrical connection reliability. More preferably, it is 5000 Pa･s or less, More preferably, it is 4000 Pa･s or less. From these viewpoints, the minimum melt viscosity of the first adhesive is preferably from 1000 Pa･s to 10000 Pa･s, more preferably from 1500 Pa･s to 5000 Pa･s, still more preferably from 2000 Pa･s to 4000 Pa･s. Note that the melt viscosity can be measured using a rotational rheometer (for example, ARES-G2 manufactured by TA Instruments). In addition, the said melt viscosity is the melt viscosity measured on the following conditions. Measurement conditions Heating rate: 10°C/min Frequency: 10Hz Temperature range: 30℃～150℃

(Second Adhesive) The second adhesive does not substantially contain a flux compound. "Not containing substantially" 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 effects 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 2nd adhesive agent, the adhesive agent of a radical hardening system is mentioned, for example. The reason why the effects of the present invention are remarkably obtained by such an adhesive is not clear, but the inventors of the present invention presume as follows.

That is, in conventional film adhesives containing flux compounds, since the flux component deactivates radicals, radical curing systems cannot be used, and cationic curing systems using epoxy groups or the like are often used. In this hardening system (reaction system), hardening proceeds by nucleophilic addition reaction, so the hardening speed is slow, and voids may be generated after crimping. In conventional film adhesives, it is presumed that defects (such as peeling of the semiconductor material at a reflow temperature of around 260° C., poor connection at the connection portion, etc.) have occurred due to voids during packaging. On the other hand, since the second adhesive does not substantially contain a flux compound, the curing system can be a radical curing system, and a sufficient curing rate can be obtained. Therefore, it is presumed that by using the second adhesive agent for the second layer, voids are less likely to be generated even when pressure bonding is performed at high temperature for a short time, and the effect of the present invention becomes remarkable. In addition, in the present embodiment, since a sufficient curing speed is obtained, even when solder is used for the connecting portion, for example, the film adhesive can be cured in a temperature range lower than the melting temperature of the solder. Therefore, it is possible to sufficiently suppress occurrence of spatter and flow of solder to cause poor connection.

Hereinafter, the second adhesive contains a radically polymerizable compound (hereinafter referred to as "(A) component" as the case may be), a thermal radical generating agent (hereinafter referred to as "(B) component" as the case may be), and optionally One embodiment of the polymer component (hereinafter referred to as "(C) component" as the case may be) and filler (hereinafter referred to as "(D) component" as the case may be) will be described.

[(A) Component: Radical polymerizable compound] The component (A) is a compound that undergoes a radical polymerization reaction with generation of radicals by heat, light, radiation, electrochemical action, or the like. As (A) component, a (meth)acrylic compound, a vinyl compound, etc. are mentioned. The (A) component is preferably a (meth)acrylic compound from the viewpoint of excellent durability, electrical insulation, and heat resistance. The (meth)acrylic compound is not particularly limited as long as it has one or more (meth)acrylic acid groups ((meth)acryl groups) in the molecule. For example, bisphenol A-containing, bisphenol F type, naphthalene type, phenol novolak type, cresol novolak type, phenol aralkyl type, biphenyl type, triphenylmethane type, dicyclopentadiene type, fennel type, adamantane type or heterotrimer (meth)acrylic compounds with a cyanic acid-type skeleton; various polyfunctional (meth)acrylic compounds (excluding (meth)acrylic compounds containing the skeleton), and the like. Pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, trimethylolpropane di(meth)acrylate etc. are mentioned as a polyfunctional (meth)acrylic compound. (A) The component can be used individually by 1 type or in combination of 2 or more types.

The component (A) preferably has a bisphenol A-type skeleton, bisphenol F-type skeleton, naphthalene-type skeleton, fennel-type skeleton, adamantane-type skeleton or It has an isocyanuric acid-type skeleton, and more preferably has a fennel-type skeleton. The (A) component is more preferably a (meth)acrylate having any one of the above-mentioned skeletons from the viewpoint that generation of pores can be further suppressed.

(A) It is preferable that a component is solid at room temperature (25 degreeC). Solids are less likely to generate voids than liquids, and the second adhesive before hardening (B stage) has low tack and excellent handleability. Examples of the component (A) that is solid at room temperature (25°C) include (meth)acrylates having a bisphenol A-type skeleton, a fennel-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. When the number of functional groups is large, the hardened network (network) rapidly expands, and unreacted groups may remain. On the other hand, if the number of functional groups is 3 or less, the number of functional groups will not be too many, and it will be easy to sufficiently perform curing in a short time, so it will be easy to suppress the decrease in the curing reaction rate.

(A) The molecular weight of component is preferably less than 2000, more preferably 1000 or less. (A) The smaller the molecular weight of the component, the easier the reaction is, and the higher the curing reaction rate is.

From the viewpoint of suppressing the reduction of hardening components and making it easy to sufficiently control the resin flow after hardening, the content of component (A) is preferably at least 10% by mass, more preferably 15% by mass, based on the total mass of the second adhesive. %above. From the standpoint of preventing the cured product from becoming too hard and easily suppressing the increase in warpage of the package, the content of the component (A) is preferably at most 50% by mass, more preferably 40% by mass, based on the total mass of the second adhesive. Mass% or less. From these viewpoints, the content of the component (A) is preferably from 10% by mass to 50% by mass, more preferably from 15% by mass to 40% by mass, based on the total mass of the second adhesive.

From the standpoint of suppressing a decrease in curability and easily suppressing a decrease in adhesive force, the content of the component (A) is preferably at least 0.01 parts by mass, more preferably at least 0.05 parts by mass, and still more preferably at least 0.05 parts by mass relative to 1 part by mass of the component (C). It is 0.1 mass part or more. The content of the component (A) is preferably at most 10 parts by mass, more preferably at most 5 parts by mass, relative to 1 part by mass of the component (C) from the viewpoint of easily suppressing a decrease in film formability. From these viewpoints, the content of the component (A) is preferably from 0.01 to 10 parts by mass, more preferably from 0.05 to 5 parts by mass, and still more preferably from 0.1 to 1 part by mass of the component (C). Parts by mass to 5 parts by mass.

[(B) Component: Thermal Radical Generator] The component (B) is not particularly limited as long as it functions as a curing agent for the component (A), but is preferably a thermal radical generating agent from the viewpoint of excellent workability.

Examples of the thermal radical generating agent include azo compounds, peroxides (organic peroxides, etc.), and the like. The thermal radical generator is preferably a peroxide, more preferably an organic peroxide. In this case, a radical reaction does not proceed in the step of drying the solvent when forming a film form, and it is excellent in handleability and storage stability. Therefore, when a peroxide is used as a thermal radical generating agent, further excellent connection reliability can be easily obtained. 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, the organic peroxide is preferably at least one selected from the group consisting of hydroperoxides and dialkyl peroxides from the viewpoint of excellent heat resistance. Examples of dialkyl peroxides include dicumyl peroxide, di-tert-butyl peroxide, and the like.

The content of the component (B) is preferably at least 0.5 parts by mass, more preferably at least 1 part by mass, based on 100 parts by mass of the component (A) from the viewpoint of easy and sufficient hardening. The content of the component (B) is preferably at most 10 parts by mass, more preferably at most 5 parts by mass, relative to 100 parts by mass of the component (A). When the upper limit of the content of the component (B) is within the above-mentioned range, rapid curing is suppressed to suppress an increase in the number of reaction points, thereby suppressing the shortening of the molecular chain and the remaining of unreacted groups. Therefore, if the upper limit of the content of (B) component is the said range, it will become easy to suppress the fall of reliability. From these viewpoints, the content of (B) component is preferably from 0.5 to 10 parts by mass, more preferably from 1 to 5 parts by mass, based on 100 parts by mass of (A) component.

[(C) Component: Polymer Component] The second adhesive may further contain a polymer component. (C) Components include: epoxy resin, phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate resin, (meth)acrylic resin, polyester resin , polyethylene resin, polyether resin, polyetherimide resin, polyvinyl acetal resin, urethane resin, acrylic rubber, etc., among them, from the viewpoint of excellent heat resistance and film formability, Preferably, it is selected from epoxy resin, phenoxy resin, polyimide resin, (meth)acrylic resin, urethane resin, acrylic rubber, cyanate resin and polycarbodiimide resin 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 the (C) Component may 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 contained in (C)component.

The glass transition temperature (Tg) of the component (C) is preferably at most 120° C., more preferably at most 100° C., and still more preferably Below 85°C. In the case of these ranges, bumps formed on a semiconductor wafer, unevenness of electrodes or wiring patterns formed on a substrate can be easily filled with a film-like adhesive for semiconductors (it is easy to suppress the start of hardening reaction) , It is easy to suppress the occurrence of voids due to air bubbles remaining. 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 , Temperature rise rate 10°C/min, measurement environment: Tg when measured under the condition of air.

(C) The weight average molecular weight of the component is preferably 10,000 or more in terms of polystyrene, more preferably 30,000 or more, further preferably 40,000 or more, and most preferably 50,000 or more in order to independently exhibit good film formability. . When a weight average molecular weight is 10000 or more, it becomes easy to suppress fall of film formability.

[(D) Ingredient: 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 wafers are connected. As (D) component, the filler similar to what was mentioned as (e) component in a 1st adhesive agent can be used. Examples of preferable fillers are also the same.

From the viewpoint of suppressing the decrease in heat dissipation, easily suppressing the generation of voids, increasing the moisture absorption rate, etc., the content of the component (D) is preferably 15% by mass or more based on the total mass of the second adhesive , more preferably at least 20% by mass, further preferably at least 40% by mass. Based on the total mass of the second adhesive, it is easy to suppress the decrease in the fluidity of the second adhesive due to the increase in viscosity and the occurrence of trapping of the filler on the connection part, and to easily suppress the decrease in connection reliability. , The content of the component (D) is preferably at most 90% by mass, more preferably at most 80% by mass. From these viewpoints, based on the total mass of the second adhesive, the content of the component (D) is preferably from 15% by mass to 90% by mass, more preferably from 20% by mass to 80% by mass, and still more preferably 40% by mass to 80% by mass.

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

[other ingredients] A polymerizable compound other than a radically polymerizable compound (for example, a cationically polymerizable compound and an anionically polymerizable compound) may also be formulated in the second adhesive. In addition, the same other components as those of the first adhesive may be compounded in the second adhesive. These can be used individually by 1 type or in combination of 2 or more types. What is necessary is just to adjust suitably so that the effect of each additive may express about the compounding quantity of these.

The hardening reaction rate after the second adhesive is kept at 200° C. for 5 seconds is preferably 80% or more, more preferably 90% or more. If the hardening reaction rate at 200°C (below the solder melting temperature)/5 seconds is 80% or more, it is easy to suppress the decrease in connection reliability due to solder spattering and flow during connection (above the solder melting temperature). The hardening reaction rate can be obtained by the following method: After putting 10 mg of the second adhesive (unhardened layer without flux) into the aluminum pot, use DSC (Perkin Elmer Japan ) Co., Ltd., trade name: DSC-7 type) to measure the calorific value. Specifically, 10 mg of the second adhesive (unhardened layer not containing flux) was put in an aluminum pot, and the measurement sample thus obtained was placed on a hot plate heated to 200°C. After 5 seconds, the measurement sample was removed from the heating plate. The measurement samples after the heat treatment and the untreated measurement samples were respectively measured by DSC. From the obtained calorific value, the hardening reaction rate was calculated by the following formula. Hardening reaction rate (%)=(1-[calorific value of measured sample after heat treatment]/[calorific value of untreated measured sample])×100

When the second adhesive contains an anionically polymerizable epoxy resin (particularly, 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. Preferably, content of an epoxy resin is 20 mass parts or less with respect to 80 mass parts of (A) components, More preferably, it does not contain an epoxy resin.

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

Regarding the thickness of the film adhesive for a semiconductor according to this embodiment, when the sum of the heights of the connection portions is represented as x and the total thickness of the film adhesive for a semiconductor is represented as y, the From the viewpoint of connectivity and fillability of the adhesive, the relationship between x and y preferably satisfies 0.70x≦y≦1.3x, more preferably satisfies 0.80x≦y≦1.2x. The total thickness of the film adhesive for semiconductors may be, for example, 10 μm to 100 μm, or 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 to 50 μm, 3 μm to 50 μm, 4 μm to 30 μm, or 5 μm to 20 μm.

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

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

The film-form adhesive agent for semiconductors of this embodiment may further contain another layer other than a 1st layer and a 2nd layer. For example, the semiconductor film-form adhesive agent of this embodiment may contain the mixed layer containing a 1st layer and a 2nd layer. In addition, the film-form adhesive for semiconductors of this embodiment may include a substrate on the surface of the first layer opposite to the second layer, and/or on the surface of the second layer opposite to the first layer. film and/or protective film. In this case, an adhesive layer can be provided between a base film or a protective film, and a 1st layer, and/or between a base film, a protective film, and a 2nd layer.

In the film-form adhesive agent for semiconductors, a 1st layer and a 2nd layer may adjoin. In this case, the first layer and the second layer are preferably formed so as not to be separated from each other. For example, the peel strength between the first layer and the second layer may be 10 N/m or more.

From the viewpoint of reliability, the minimum melt viscosity of the film adhesive is preferably at least 1000 Pa･s, more preferably at least 1500 Pa･s, further preferably at least 2000 Pa･s. When the minimum melt viscosity is 1000 Pa･s or more, the thermal expansion of voids involved during packaging is suppressed, and the possibility of peeling during long-term use (such as a reliability test) is reduced. On the other hand, the minimum melt viscosity of the film adhesive is preferably 10,000 Pa･s or less in terms of sufficiently removing the first layer during solder connection, reducing resin sticking, and excellent electrical connection reliability. More preferably, it is 5000 Pa･s or less, More preferably, it is 4000 Pa･s or less. From these viewpoints, the minimum melt viscosity of the film adhesive is preferably from 1000 Pa･s to 10000 Pa･s, more preferably from 1500 Pa･s to 5000 Pa･s, still more preferably from 2000 Pa･s to 4000 Pa･s. The minimum melt viscosity of the film adhesive can be measured by the same method as the minimum melt viscosity of the first adhesive.

<Manufacturing method of film adhesive for semiconductor> The film-like adhesive for semiconductors of this embodiment can be obtained, for example, by preparing a first film-like adhesive including the first layer and a second film-like adhesive including the second layer, and making the first film-like adhesive including the first layer The first film adhesive is bonded to the second film adhesive including the second layer.

In the step of preparing the first film adhesive, for example, other components such as (a) component, (b) component, and (c) component, and optionally added (d) component and (e) component are first added to In an organic solvent, a resin varnish (coating varnish) is prepared by dissolving or dispersing by stirring, kneading, or the like. Then, the resin varnish is coated on the base film or protective film subjected to mold release treatment using a knife coater, roll coater, applicator, etc., and the organic solvent is reduced by heating, so that it can be used in The first layer containing the first adhesive is formed on the base film or the protective film.

As the organic solvent used in the preparation of the resin varnish, it is preferable to have the property of dissolving or dispersing each component uniformly, for example, dimethylformamide, dimethylacetamide, N-methyl -2-Pyrrolidone, Dimethylsulfene, 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 individually or in combination of 2 or more types. Stirring mixing and kneading at the time of preparing a resin varnish can be performed using a mixer, an attritor, a triple roll, a ball mill, a bead mill, or a homogenizer, for example.

The base film and 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 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. A base film and a protective film are not limited to the single-layer film which consists of these films, The multilayer film which consists of 2 or more types of materials may be sufficient. In addition, the base film and the protective film may include an adhesive layer on one surface thereof.

The drying conditions for volatilizing the organic solvent from the resin varnish coated on the base film are preferably conditions under which the organic solvent is sufficiently volatilized, and specifically, heating is preferably performed at 50° C. to 200° C. for 0.1 minutes to 90 minutes. . As long as it does not affect the porosity or viscosity adjustment after sealing, the organic solvent is preferably removed to be 1.5% by mass or less with respect to the total mass of the first film-shaped adhesive.

In the step of preparing the second film adhesive, except for using components (A) and (B), and other components such as component (C) added if necessary, the same method as the first layer can be applied to The second layer containing the second adhesive is formed on the base film or the protective film.

As a method of bonding a 1st film-form adhesive agent and a 2nd film-form adhesive agent together, methods, such as heating press, roll lamination, and vacuum lamination, are mentioned, for example. Lamination can be performed, for example under heating conditions of 30°C to 120°C.

The film adhesive for semiconductors of this embodiment can also be obtained, for example, by forming one of the first layer or the second layer on the base film, and then forming the first layer or the second layer on the obtained first layer or the second layer. The other of layer 1 or layer 2 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 above-mentioned film adhesive with a base material.

The film-form adhesive agent for semiconductors of this embodiment can also be obtained by forming a 1st layer and a 2nd layer substantially simultaneously on a base film, for example. This method may be a method of forming the first layer and the second layer by applying the first adhesive agent and the second adhesive agent substantially simultaneously and drying them all at once (simultaneous multi-layer coating method), or it may be a method by applying A method in which the first adhesive is applied, the second adhesive is applied, and dried at one time to form the first layer and the second layer (sequential multi-layer coating method).

＜Semiconductor Devices＞ The semiconductor device according to this embodiment will be described below using FIGS. 1( a ), 1 ( b ), 2 ( a ), and 2 ( b ). 1( a ) and FIG. 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; The connection bump 30 which connects the wiring 15 of the wafer 10 and the substrate 20 to each other, and the hardened product including adhesives (first adhesive and second adhesive) which fill the space between the semiconductor wafer 10 and the substrate 20 without gaps The sealing part 40. The semiconductor chip 10 and the substrate 20 are flip-chip connected through the wiring 15 and the connection bump 30 . The wires 15 and the connection bumps 30 are sealed by hardening of the adhesive and blocked from the external environment. The sealing part 40 has the upper part 40a which contains the hardened material of the 1st adhesive agent, and the lower part 40b which contains the cured material of the 2nd adhesive agent.

As shown in FIG. 1( b ), the semiconductor device 200 has: the semiconductor wafer 10 and the substrate 20 facing each other, the bumps 32 respectively arranged on the surfaces of the semiconductor wafer 10 and the substrate 20 facing each other, and the bumps 32 including filling without gaps. The sealing portion 40 is a cured product of the adhesive (first adhesive and 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 through the facing bumps 32 , and are flip-chip connected. The bump 32 is sealed by the cured adhesive to block it from the external environment. The sealing part 40 has the upper part 40a which contains the hardened material of the 1st adhesive agent, and the lower part 40b which contains the cured material of the 2nd adhesive agent.

2( a ) and FIG. 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 two semiconductor chips 10 are flip-chip connected via the wiring 15 and the connection bump 30 . As shown in FIG. 2( b ), the semiconductor device 400 is the same as the semiconductor device 200 except that two semiconductor wafers 10 are flip-chip connected through the 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.

As the substrate 20, there is no particular limitation if it is a circuit substrate, and it is possible to use glass epoxy, polyimide, polyester, ceramics, epoxy, bismaleimide triazine, etc. as main components. A circuit substrate having wiring (wiring pattern) 15 formed by etching and removing unnecessary parts of the metal film on the surface of the insulating substrate; a wiring 15 formed on the surface of the insulating substrate by metal plating or the like A circuit substrate; a circuit substrate on which wiring 15 is formed by printing a conductive substance on the surface of the insulating substrate, or the like.

Connection parts such as wiring 15 and 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 and the like are used as main components, and various metals may be contained.

Among these metals, gold, silver, and copper are preferable, and silver and copper are more preferable from the viewpoint of forming a package having excellent electrical conductivity and thermal conductivity of the connection portion. From the viewpoint of 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 the metal at room temperature, the productivity may decrease and the cost may increase. Therefore, from the viewpoint of suppressing the formation of the oxide film, gold, silver, copper, and solder are preferred. , more preferably gold, silver, solder, further preferably gold, silver.

On the surface of the wiring 15 and the bump 32, gold, silver, copper, solder (main components such as tin-silver, tin-lead, tin-bismuth, tin- copper, etc.), tin, nickel, etc. as the main component of the metal layer. The metal layer may contain only a single component or multiple components. In addition, the metal layer may also be a single layer or a structure formed by stacking multiple metal layers.

In addition, in the semiconductor device of the present embodiment, a plurality of structures (packages) shown in the semiconductor device 100 to the semiconductor device 400 may be stacked. In this case, the semiconductor devices 100 to 400 can also be made by including gold, silver, copper, solder (the main component is, for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc. ), tin, nickel, etc. bumps, wiring, etc., and 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 wires 15 formed on the interposer 50 are connected to the wires 15 of the semiconductor chip 10 through the connection bumps 30 , whereby the semiconductor chip 10 and the interposer 50 are flip-chip connect. The space between the semiconductor wafer 10 and the interposer 50 is filled with cured products of the adhesive (the first adhesive and the second adhesive) without gaps, thereby constituting the sealing portion 40 . On the surface of the semiconductor wafer 10 opposite to the interposer 50 , the semiconductor wafer 10 is repeatedly laminated via the wiring 15 , the connection bump 30 and the sealing portion 40 . The wiring lines 15 on the front and back pattern surfaces of the semiconductor wafer 10 are connected to each other by the through electrodes 34 filled in holes penetrating the inside of the semiconductor wafer 10 . Note that copper, aluminum, or the like can be used as the material of the penetration electrode 34 .

With this TSV technology, signals can also be obtained from the backside of the semiconductor chip, which is not normally used. Furthermore, since the penetrating electrodes 34 are vertically inserted into the semiconductor wafers 10 , the distance between the opposing semiconductor wafers 10 and between the semiconductor wafers 10 and the interposer 50 can be shortened to achieve flexible connection. In such TSV technology, the film-form adhesive for semiconductors of this embodiment can be applied as a film-form adhesive for semiconductors between opposing semiconductor wafers 10 and between the semiconductor wafers 10 and the interposer 50 .

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

<Manufacturing method of semiconductor device> The manufacturing method of the semiconductor device according to this embodiment will be described below using FIGS. 4( a ) to 4 ( c ). 4(a) to 4(c) are diagrams schematically showing one embodiment of the method for manufacturing a semiconductor device according to the present invention, and FIG. 4(a), FIG. 4(b) and FIG. 4(c) showing each step ) shows the cross section of the semiconductor device.

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

Next, as shown in FIG. 4( a ), a connection bump 30 is formed at the opening of the solder resist 60 . Then, as shown in FIG. 4( b ), on the substrate 20 on which the connection bumps 30 and the solder resist 60 are formed, the surface on the side of the second layer 41 b including the second adhesive is on the side of the substrate 20 . The film-form adhesive for semiconductors of this embodiment (hereinafter, referred to as "film-form adhesive" as appropriate) 41 . Attaching of the film adhesive 41 can be performed by heat press, roll lamination, vacuum lamination, etc. 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-form adhesive agent 41 may be performed so that the surface by the side of the 1st layer 41a containing a 1st adhesive agent may become the board|substrate 20 side.

After sticking the film adhesive 41 on the board|substrate 20 as mentioned above, the wiring 15 and the connection bump 30 of the semiconductor wafer 10 are aligned using the connection apparatus, such as a flip chip bonder. Next, the semiconductor wafer 10 and the substrate 20 are pressure-bonded while being heated at a temperature equal to or higher than the melting point of the connection bump 30, 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 hardened film adhesive 41 seals and fills the gap between the semiconductor wafer 10 and the substrate 20 . The semiconductor device 600 is obtained through the above.

The crimping time may be, for example, 5 seconds or less. In this embodiment, since the film adhesive 41 of the above-mentioned embodiment is used, even if the pressure-bonding time is 5 seconds or less, a semiconductor device having 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 state where the film-like adhesive for semiconductors is interposed) after alignment, and heat treatment in a reflow furnace to make the connection bump 30 is melted to connect the semiconductor wafer 10 and the substrate 20 . Since it is not necessary to form a metal joint in the stage of temporary fixing, compared with the above-mentioned method of pressing while heating, it is possible to perform pressure bonding under a low load, short time, and low temperature, thereby improving productivity and enabling Deterioration of the connection part is suppressed.

In addition, after connecting the semiconductor wafer 10 and the substrate 20, heat treatment in an oven or the like may be performed to further improve connection reliability and insulation reliability. The heating temperature is preferably a temperature at which the film adhesive hardens, more preferably a temperature at which it is completely cured. The heating temperature and heating time can be set appropriately.

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

From the viewpoint of productivity improvement, the film-like adhesive for semiconductors can also be obtained on the semiconductor wafer 10 by supplying the semiconductor wafer to which a plurality of semiconductor wafers 10 are connected, and cutting the crystal into individual pieces. A structure supplied with a film-like adhesive for semiconductors. The film adhesive for semiconductors may be supplied so as to bury wiring, bumps, and the like on the semiconductor wafer 10 by, for example, attachment methods such as heat pressing, roll lamination, and vacuum lamination. In this case, since the supply amount of resin is fixed, productivity improves, and generation|occurrence|production of voids and the fall of crystal cutting property by filling insufficiency can be suppressed.

The connection load can be set in consideration of variations in the number and height of the connection bumps 30 , and the amount of deformation of the connection bumps 30 or the wiring of the bumps receiving the connection portion due to pressurization. Regarding the connection temperature, the temperature of the connection portion is preferably not less than the melting point of the connection bump 30 , but it may be a temperature at which metal bonding of each connection portion (bump and wiring) can be formed. When the connecting bump 30 is a solder bump, it is preferably about 240° C. or higher.

The connection time at the time of connection varies depending on the constituent metals of the connection part, but from the viewpoint of improving productivity, the shorter the time, the better. When the connection bump 30 is a solder bump, the connection time is preferably less than 20 seconds, more preferably less than 10 seconds, and still more preferably less than 5 seconds. In the case of copper-copper or copper-gold metal connection, the connection time is preferably 60 seconds or less.

The film-form adhesive for semiconductors according to the present embodiment exhibits excellent reflow resistance and connection reliability in the flip-chip connection portions of the various package structures described above.

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

Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to an Example.

＜Fabrication of monolayer film including flux-containing layer＞ The compounds used in the preparation of the single-layer film including the flux-containing layer are shown below. (a) epoxy resin ・Multifunctional solid epoxy resin containing a trisphenolmethane 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., commercial product name "2MAOK-PW") (c) Flux ・Glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd., with a melting point of about 98°C) ・2-Methylglutaric acid (manufactured by Sigma Aldrich, melting point about 78°C) ・3-Methylglutaric acid (Tokyo Chemical Co., Ltd., melting point about 87°C) (d) Polymer composition ・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 40000) (e) filler ・Silica filler (manufactured by Admatechs Co., Ltd., trade name "SE2050", average particle size: 0.5 μm) ・Epoxysilane surface treatment filler (manufactured by Admatechs Co., Ltd., SE2050-SEJ, average particle size: 0.5 μm) ・Methacrylic acid surface-treated nano-silica filler (manufactured by Admatechs Co., Ltd., trade name "YA100C-MLE", average particle size: about 100 nm) ・Methacrylic acid surface-treated nano-silica filler (Admatechs Co., Ltd., trade name "YA050C-MJE", average particle size: about 50 nm) ・Organic filler (resin filler, manufactured by Rohm and Haas Japan Co., Ltd., trade name "EXL-2655", core-shell organic microparticles)

The formulation amount (unit: parts by mass) of epoxy resin, hardener, polymer component, flux, inorganic filler and organic filler shown in Table 1 is expressed by NV value ([mass of coating components after drying]/[before drying The mass of paint components] × 100) is added to the organic solvent (methyl ethyl ketone) in such a way that it becomes 60%. Then, add Φ 1.0 mm beads and Φ 2.0 mm beads of the same mass as the solid components (epoxy resin, hardener, flux, polymer components, inorganic fillers, and organic fillers), and use a bead mill (Japan Fritsch (Fritsch Japan Co., Ltd., planetary pulverizer P-7) was stirred for 30 minutes. After stirring, beads were removed by filtration to prepare a coating varnish containing the first adhesive.

Apply the obtained coating varnish to a base film (manufactured by Teijin DuPont Film Co., Ltd., trade name "Purex (Purex) A54") with a small precision coating device (manufactured by Yashii Seiki Co., Ltd.) , and dried in a clean oven (manufactured by ESPEC Co., Ltd.) (80°C/10 min) to obtain the single-layer film (A-1) and single-layer film (A-1) shown in Table 1. 2), single-layer film (A-3), single-layer film (A-4) and single-layer film (A-5) 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 20 μm.

[Table 1] Type of film A-1 A-2 A-3 A-4 A-5 epoxy resin EP1032H60 45 45 45 45 45 YL983U 20 20 20 20 20 hardener 2MAOK-PW 2 2 2 4 4 Flux glutaric acid 2 - - 4 4 2-methylglutaric acid - 2 - - - 3-methylglutaric acid - - 2 - - Polymer composition ZX-1356-2 30 30 30 - - FX-293 - - - 20 20 filler SE2050 15 15 15 15 15 SE2050-SEJ 15 15 15 15 15 YC100C-MLE - - - - 15 YA050C-MJE 45 45 45 45 45 EXL-2655 10 10 10 10 10

＜Fabrication of single-layer films including layers without flux＞ The compounds used in the preparation of the single-layer film including the flux-free layer are shown below.

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

(B) Thermal free radical generator ・Dicumyl peroxide (NOF Corporation, Percumyl (registered trademark) D) ・Di-tertiary butyl peroxide (NOF Corporation, Perbutyl (registered trademark) D) ・1,4-Bis-((tert-butylperoxide)diisopropyl)benzene (NOF Corporation, Perbutyl (registered trademark) P)

(C) Polymer composition ・Acrylic resin (Hitachi Chemical Co., Ltd., KH-CT-865, weight average molecular weight Mw: 100,000, Tg: 10°C) ・Urethane resin (DIC Covestro Polymer Co., Ltd., Lycra (Pandex) T-8175N, Tg: about -23°C)

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

Add the (meth)acrylic compound, polymer component, inorganic filler, and organic filler in the amount (unit: parts by mass) shown in Table 2 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 of the same mass as the solid content ((meth)acrylic acid compound, polymer component, inorganic filler and organic filler), and use a bead mill (Japan Fritz (Fritsch Japan Co., Ltd., planetary pulverizer P-7) and stirred for 30 minutes. After stirring, the beads were removed by filtration. Next, a thermal radical generating agent is added to the obtained mixture and stirred and mixed to prepare a coating varnish including a second adhesive.

The obtained coating varnish was coated on a substrate film (manufactured by Teijin DuPont Film Co., Ltd., trade name "Purex (Purex) A54") with a small precision coating device (Yaijing Seiki), and the Drying in an oven (manufactured by ESPEC Co., Ltd.) (80°C/10 min) to obtain the single-layer film (B-1), single-layer film (B-2), single-layer film shown in Table 2 A single-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) were used as the second film. The thickness of the layer not containing the flux in the single-layer film (B-1) to the single-layer film (B-7) was set to 20 μm.

[Table 2] Type of film B-1 B-2 B-3 B-4 B-5 B-6 B-7 (Meth)acrylic compounds EA-0200 45 - - 45 45 55 55 EA-1020 - 45 - - - - - A-9300 - - 45 - - - - thermal free radical generator Percumyl D 0.5 0.5 0.5 - - - - Perbutyl D - - - 0.5 - - - Perbutyl P - - - - 0.5 1 1 Polymer composition KH-CT-865 30 30 30 30 30 - - T-8175N - - - - - 15 30 filler SE2050 15 15 15 15 15 - - SE2050-SEJ 15 15 15 15 15 - - YC100C-MLE - - - - - 25 25 YA050C-MJE 45 45 45 45 45 75 75 EXL-2655 10 10 10 10 10 10 10

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

＜Evaluation 1＞ (Determination of minimum melt viscosity) Using a rotational rheometer (manufactured by TA Instruments, trade name: ARES-G2), the first adhesive, the second adhesive, and the film adhesive (the layer containing the flux and the layer without the flux) were measured. layer laminates) melt viscosity. The evaluation sample of the melt viscosity of a film adhesive agent was produced in the following procedure. First, two of the single-layer films produced above (the first film and the second film) were laminated at 50° C. to produce a double-layer film with a total thickness of 40 μm. The combinations of single-layer films were set as shown in Table 3 and Table 4. This bilayer film was cut, and the cut bilayer films were laminated to each other to produce a four-layer film (laminated film) with a total thickness of 80 μm. Cutting of the laminated film and lamination of the cut laminated film were repeated in the same procedure 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°C/min Frequency: 10Hz Temperature range: 30℃～150℃

The minimum melt viscosity of the first adhesive is 2000 Pa･s～4000 Pa･s (measured value at 130°C), and the minimum melt viscosity of the second adhesive is 1000 Pa･s～3000 Pa･s (measured value at 120°C 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 adhesives obtained in Examples and Comparative Examples and the semiconductor devices produced using the film adhesives were evaluated for initial connectivity, porosity, solder wettability, and bleeding amount by the methods shown below. , And insulation reliability evaluation. The results are shown in Table 3 and Table 4.

(Initial Connectivity Evaluation) The film-like adhesive produced in the example or comparative example was cut into a predetermined size (8 mm in length x 8 mm in width x 40 μm in thickness), and the base film excluding the adhesive layer was peeled off. Laminated on a semiconductor wafer with solder bumps (wafer size: 7.3 mm in length x 7.3 mm in width x 0.15 mm in thickness, bump height: the sum of the height of the copper pillar and the height of the solder is about 40 μm, the bump Number: 328). The base film with the adhesive layer was peeled off, and the laminated wafer was packaged with the flux-containing layer facing down using a flip-chip package 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). In this manner, a semiconductor device A in which the glass epoxy substrate and the semiconductor wafer with solder bumps are daisy-chain-connected is produced in the same manner as in (a) to (c) of FIG. 4 .

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

(porosity evaluation) An image of the appearance of the semiconductor device A produced by the method described above was taken with an ultrasonic imaging diagnostic device (trade name "Insight-300", manufactured by Insight Co., Ltd.), and was used Scanner GT-9300UF (manufactured by Seiko Epson Co., Ltd., brand name) captures the image of the adhesive layer (layer including hardened film adhesive for semiconductors) on the wafer, and uses image processing software Adobe Photoshop (registered trademark), through tone correction and two-grayscale conversion to identify the pore part, and calculate the proportion of the pore part through the histogram. The area of the adhesive portion on the wafer was taken as 100%, and the case where the void generation rate was 3% or less was evaluated as "AA" (good), and the case where the void generation rate was more than 3% and 5% or less was evaluated as "A" (good), "B" (poor) when the void generation ratio was more than 5% and 10% or less, and "C" (failure) when the void generation ratio was more than 10%.

(Solder wettability evaluation) Regarding the semiconductor device A produced by the above method, the cross section of the connection part was observed, and the case where the solder wetting on the upper surface of the Cu wiring was 100% to 50% was evaluated as "A" (good), and the The case where the wetting of the solder was 50% to 0% was evaluated as "B" (failure), and the case where solder spattering occurred was evaluated as "C" (failure).

(Exudation measurement) Using a metal microscope (manufactured by Keyence Co., Ltd.), the semiconductor device A produced by the above method was observed from the upper surface of the device, and the source of seepage from the peripheral portion (four sides) of the semiconductor wafer was measured. The amount of hardened film adhesive (the width of the oozing part). The measurement was performed for each side of the semiconductor device, and the average value of the four sides was calculated as the bleeding amount.

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

(Insulation Reliability Test B [HAST Test: Highly Accelerated Storage Test]) Attach the film-like adhesive (thickness: 40 μm) prepared in the example or comparative example to the comb-shaped electrode to evaluate TEG (manufactured by Hitachi Chemical Co., Ltd., wiring pitch: 50 μm), using a flip-chip packaging device "FCB3" (manufactured by Panasonic Co., Ltd., trade name), the semiconductor wafer (wafer Dimensions: 7.3 mm in length x 7.3 mm in width x 0.15 mm in thickness, bump height: the sum of the height of the copper pillar and the height of the solder is about 40 μm, the number of bumps: 328) with the side with the solder facing down state to be packaged (in packaging conditions: temperature of the crimping joint is 180°C, crimping time is 3 seconds, and crimping pressure is 0.5 MPa, after thermocompression bonding (gelation step of the adhesive), the temperature of the crimping joint is raised to 260°C, And continuously carry out thermocompression bonding at the crimping joint temperature of 260°C, crimping time of 3 seconds, and crimping pressure of 0.5 MPa). Thereby, a semiconductor device C is obtained. The crimped semiconductor device C was cured in a clean oven (manufactured by ESPEC Co., Ltd.) at 175°C for two hours, and the cured sample was set in the accelerated life test device (Hirayama Manufacturing Co., Ltd. Insulation resistance was measured under conditions: 130°C/85%RH/100 hours, 5 V applied, under the trade name "PL-422R8". The insulation resistance after 100 hours was evaluated as "A" when it was 10 ⁸ Ω or more, "B" when it was 10 ⁷ Ω or more and less than 10 ⁸ Ω, and "B" when it was less than 10 ⁷ Ω. "C".

[table 3] Example 1 2 3 4 5 6 7 8 9 10 1st film A-1 A-1 A-1 A-1 A-1 A-2 A-3 A-4 A-5 A-5 2nd film B-1 B-2 B-3 B-4 B-5 B-1 B-1 B-6 B-6 B-7 Evaluation of initial connectivity A A A A A A A A A A Pore Evaluation AAA A A AAA AAA AAA AAA AAA AAA AAA Solder wettability evaluation A A A A A A A A A A Exudation 26 29 29 29 28 29 26 20 twenty two 18 Insulation reliability A (HAST resistance) A A A A A A A A A A Insulation reliability B (HAST resistance) A A A A A A A A A A

[Table 4] comparative example 1 2 3 4 5 6 7 8 9 10 11 12 1st film A-1 A-2 A-3 A-4 A-5 B-1 B-2 B-3 B-4 B-5 B-6 B-7 2nd film A-1 A-2 A-3 A-4 A-5 B-1 B-2 B-3 B-4 B-5 B-6 B-7 Evaluation of initial connectivity B B B B B C C D. D. C D. D. Pore Evaluation C C C B B AAA A A AAA AAA AAA AAA Solder wettability evaluation C C C C C B B B B B B B Exudation 164 172 179 145 137 28 36 33 25 27 29 25 Insulation reliability A (HAST resistance) C C C C C C C C C C C C Insulation reliability B (HAST resistance) A A B A A C C C C C C C

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

10: Semiconductor wafer 15: Wiring (connection part) 20: Substrate (wiring circuit substrate) 30: Connection bump 32: bump (connection part) 34: Through electrode 40: sealing part 40a: upper part 40b: lower part 41: Film adhesives for semiconductors (film adhesives) 41a: Tier 1 41b: Layer 2 50: Interposer 60: Solder resist 100, 200, 300, 400, 500, 600: semiconductor devices

1( a ) and FIG. 1( b ) are schematic cross-sectional views showing an embodiment of the semiconductor device of the present invention. 2( a ) and FIG. 2( b ) are schematic cross-sectional views showing another embodiment of the semiconductor device of the present invention. 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 sectional views schematically showing an embodiment of the method for manufacturing a semiconductor device according to the present invention.

10: Semiconductor wafer

15: Wiring (connection part)

20: Substrate (wiring circuit substrate)

30: Connection 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 comprising a first adhesive containing a thermosetting resin, a curing agent, and a flux compound; and being disposed on the first layer and comprising The second layer of the second adhesive, the second adhesive does not substantially contain a flux compound, and the thermosetting resin is selected from the group consisting of epoxy resin, phenol resin and polyimide resin At least one of the above-mentioned second adhesives contains a radical polymerizable compound and a thermal radical generating agent. The film adhesive for semiconductors according to claim 1, wherein the hardening reaction rate of the second adhesive after being kept at 200° C. for 5 seconds is 80% or more. The film adhesive for semiconductors according to claim 1, wherein the thermal radical generating agent is a peroxide. The film adhesive for semiconductors according to claim 1, wherein the radically polymerizable compound is a (meth)acrylic acid compound. The film-like adhesive for semiconductors according to claim 4, wherein the (meth)acrylic compound has a fennel-type skeleton. The film-form adhesive for semiconductors according to any one of Claims 1 to 5, wherein the flux compound has a carboxyl group. The film-form adhesive for semiconductors according to any one of claims 1 to 5, wherein the flux compound has two or more carboxyl groups. The film-like adhesive for semiconductors as described in any one of claims 1 to 5, wherein the flux compound is a compound represented by the following formula (2);

In formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron-donating group, and n represents an integer of 0 or 1 or more. The film-form adhesive for semiconductors according to any one of Claims 1 to 5, wherein the melting point of the flux compound is 150° C. or lower. The film adhesive for semiconductors according to any one of Claims 1 to 5, wherein the curing agent is an imidazole-based curing agent. The film-like adhesive for semiconductors according to any one of claims 1 to 5, wherein the second adhesive further contains an insulating filler, and based on the total mass of the second adhesive, the insulating The content of the permanent filler is 15% by mass to 90% by mass. A method of manufacturing a semiconductor device, which is a semiconductor device in which connection portions of a semiconductor wafer and a printed circuit board are electrically connected to each other, or a semiconductor device in which connection portions of a plurality of semiconductor wafers are electrically connected to each other, the semiconductor device The manufacturing method of the device includes the step of sealing at least a part of the connecting portion with the film adhesive for semiconductor according to any one of claims 1 to 11. A semiconductor device, which is a semiconductor device in which connection portions of a semiconductor chip and a printed circuit board are electrically connected to each other, or a semiconductor device in which connection portions of a plurality of semiconductor chips are electrically connected to each other, at least a part of the connection portion is formed by, for example, The semiconductor according to any one of claims 1 to 11 is sealed with a hardened film adhesive.

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