JPWO2018225191A1 - Semiconductor film adhesive, method of manufacturing semiconductor device, and semiconductor device - Google Patents

Abstract

The film-like adhesive for semiconductors of the present invention comprises a first layer made of a first adhesive containing a flux compound, and a second adhesive provided on the first layer and containing substantially no flux compound. A second layer of agent.

Description

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

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

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

  In the case of a package that is strongly required to be further reduced in size, thickness, and function, a chip stack type package, a POP (Package On Package), a TSV (Through), in which chips are stacked using the above-described connection method to form a multi-stage. -Silicon Via) has begun to spread widely. In such a stacking / multi-stage technique, since semiconductor chips and the like are arranged three-dimensionally, the size of the package can be reduced as compared with a technique of arranging two-dimensionally. In addition, it is effective in improving the performance of semiconductors, reducing noise, reducing the mounting area, and saving power.

  By the way, in general, metal joints are used for connecting the connection portions from the viewpoint of ensuring sufficient connection reliability (for example, insulation reliability). The main metals used for the connection portions (for example, bumps and wirings) include solder, tin, gold, silver, copper, nickel, and the like, and a conductive material containing a plurality of these types is also used. In the metal used for the connection portion, the surface may be oxidized to form an oxide film, and impurities such as oxides may be attached to the surface, so that impurities may be generated on the connection surface of the connection portion. is there. If such impurities remain, connection reliability (for example, insulation reliability) between the semiconductor chip and the substrate or between the two semiconductor chips decreases, and the merit of employing the above-described connection method is impaired. It is concerned.

  As a method of suppressing the generation of these impurities, there is a method of coating a connection portion with an antioxidant film, which is known by OSP (Organic Solderability Preservatives) processing or the like. In some cases, such as a decrease in communication speed and a decrease in connectivity.

  Therefore, as a method for removing the above-mentioned oxide film and impurities, a method using a single-layer film containing a flux agent in a semiconductor material has been proposed (for example, see Patent Document 1).

International Publication No. 2013/125086

  By the way, in the flip chip package, in recent years, higher functionality and higher integration have been further advanced. As the function becomes higher and the integration becomes higher, the pitch between the wirings becomes narrower, so that the connection reliability tends to decrease.

  Further, in recent years, from the viewpoint of improving productivity, it is required to shorten the pressure bonding time at the time of assembling the flip chip package. If the pressure bonding time is reduced and the film adhesive for semiconductor is not sufficiently cured during the pressure bonding, the connection portion cannot be sufficiently protected, and a connection failure occurs when the pressure at the time of the pressure bonding is released. Furthermore, when solder is used for the connection part, if the film adhesive for semiconductors is not sufficiently cured in a temperature range lower than the solder melting temperature during crimping, the temperature during crimping may be reduced. When the temperature is reached, the solder is scattered and flowed, resulting in poor connection. On the other hand, when the film adhesive for a semiconductor is cured before the connection portions are brought into contact with each other by the pressure bonding, the adhesive is interposed between the connection portions, and a connection failure occurs.

  Then, an object of the present invention is to provide a film adhesive for semiconductors which can obtain excellent connection reliability even when the pressure bonding time is shortened. Another object of the present invention is to provide a semiconductor device using such a film adhesive for semiconductors and a method for manufacturing the same.

  The film adhesive for a semiconductor according to the present invention comprises a first layer comprising a first adhesive containing a flux compound, and a second adhesive provided on the first layer and containing substantially no flux compound. A second layer made of an agent.

  According to the film adhesive for semiconductors of the present invention, since the second layer is hardly affected by the flux compound, the second layer has a property of being quickly and sufficiently cured after the connecting portions come into contact with each other. , And excellent connection reliability (for example, insulation reliability) can be obtained even when the pressure bonding is performed at a high temperature for a short time. Moreover, according to the film adhesive for semiconductors of the present invention, since the pressure bonding time can be shortened, the productivity can be improved. Further, according to the film adhesive for a semiconductor of the present invention, the flip chip package can be easily made highly functional and highly integrated.

  By the way, in the conventional adhesive for semiconductors, when the adhesive for semiconductor is pressed at a high temperature in a state where it is not sufficiently cured, voids may be generated. On the other hand, according to the film adhesive for semiconductors of the present invention, since curing can be sufficiently performed in a short time, the generation of voids can be easily suppressed.

  In recent years, as the metal of the connection portion, there has been a tendency to use solder, copper, or the like instead of gold or the like which is hardly corroded for the purpose of cost reduction. Further, regarding the surface treatment of wirings and bumps, there is a tendency to use solder, copper or the like instead of gold or the like which is hardly corroded for the purpose of cost reduction, and a tendency to perform OSP (Organic Solderability Preservative) treatment or the like. There is. In flip-chip packages, in addition to the narrow pitch and the increase in the number of pins, such cost reductions have been progressing, so that metals that are susceptible to corrosion and insulation properties tend to be used tend to reduce insulation reliability. . On the other hand, according to the film adhesive for semiconductor of the present invention, it is possible to suppress a decrease in insulation reliability with respect to the metal.

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

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

  The thermal radical generator is preferably a peroxide. In this case, more excellent handleability and storage stability are obtained, so that more excellent connection reliability is easily obtained.

  The radical polymerizable compound is preferably a (meth) acrylic compound. In this case, more excellent connection reliability is easily obtained.

  The (meth) acrylic compound preferably has a fluorene-type skeleton. In this case, more excellent connection reliability is easily obtained.

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

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

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

  The melting point of the flux compound is preferably 150 ° C. or less. In this case, the flux is melted before the adhesive is cured during thermocompression bonding, and the oxide film such as solder is reduced and removed, so that more excellent connection reliability is easily obtained.

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

  A semiconductor device according to the present invention includes 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. In this case, at least a part of the connection portion is sealed with a cured product of the film adhesive for semiconductor described above. This semiconductor device has excellent continuous reliability (for example, insulation reliability).

  According to the present invention, it is possible to provide a film adhesive for a semiconductor that can obtain excellent connection reliability even when the pressing time is shortened. Further, according to the present invention, it is possible to provide a semiconductor device using such a film adhesive for a semiconductor and a method for manufacturing the same.

FIG. 1 is a schematic sectional view showing one embodiment of the semiconductor device of the present invention. FIG. 2 is a schematic sectional view showing another embodiment of the semiconductor device of the present invention. FIG. 3 is a schematic sectional view showing another embodiment of the semiconductor device of the present invention. FIG. 4 is a process sectional view schematically showing one embodiment of a method for manufacturing a semiconductor device of the present invention.

  In the present specification, “(meth) acrylate” means at least one of acrylate and methacrylate corresponding thereto. The same applies to other similar expressions such as “(meth) acryloyl” and “(meth) acrylic acid”. Further, the numerical range indicated by using “to” indicates a range including the numerical values described before and after “to” as the minimum value and the maximum value, respectively.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary.
In the drawings, the same or corresponding parts have the same reference characters allotted, and overlapping description will be omitted. Unless otherwise specified, the positional relationship such as up, down, left, and right is based on the positional relationship shown in the drawings.
Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

<Film adhesive for semiconductor>
The film adhesive for a semiconductor according to the present embodiment is provided on a first layer (a flux-containing layer) made of a first adhesive containing a flux compound, and on the first layer. And a second layer (a flux-free layer) made of a second adhesive not containing.

  The film adhesive for semiconductor of the present embodiment is, for example, a semiconductor device in which connection portions of a semiconductor chip and a wiring circuit board are electrically connected to each other, or a connection portion of a plurality of semiconductor chips is electrically connected to each other. It is used for sealing at least a part of the connection part in a semiconductor device which is electrically connected.

  According to the film adhesive for semiconductors of the present embodiment, in the manufacture of the semiconductor device, the pressure bonding time (for example, the pressure bonding time in the step of pressure bonding for bonding the semiconductor chip and the wiring circuit board) is reduced. Even in this case (for example, when the crimping time is set to 5 seconds or less), excellent connection reliability can be obtained.

(First adhesive)
The first adhesive contains, for example, a thermosetting component and a flux compound. Examples of the thermosetting component include a thermosetting resin and a curing agent. Examples of the thermosetting resin include an epoxy resin, a phenol resin (excluding a case where it is contained as a curing agent), and a polyimide resin. Among them, the thermosetting resin is preferably an epoxy resin. Moreover, the film adhesive for semiconductors of the present embodiment may contain a polymer component having a weight average molecular weight of 10,000 or more and a filler, if necessary.

  Hereinafter, the first adhesive includes an epoxy resin (hereinafter, sometimes referred to as “component (a)”), a curing agent (hereinafter, sometimes referred to as “component (b)”), and a flux compound (hereinafter, referred to as “component (b)”). In some cases, it is referred to as "component (c)", and, if necessary, a polymer component having a weight average molecular weight of 10,000 or more (hereinafter, sometimes referred to as "component (d)") and a filler (hereinafter, sometimes referred to as "component"). (Referred to as “component (e)”).

[Component (a): epoxy resin]
As the epoxy resin, any resin having two or more epoxy groups in a molecule can be used without particular limitation. As the component (a), for example, bisphenol A epoxy resin, bisphenol F epoxy resin, naphthalene epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, phenol aralkyl epoxy resin, biphenyl epoxy resin, triphenyl Methane type epoxy resin, dicyclopentadiene type epoxy resin and various polyfunctional epoxy resins can be used. These can be used alone or as a mixture of two or more.

  From the viewpoint of suppressing the generation of volatile components by decomposing the component (a) at the time of connection at a high temperature, when the temperature at the time of connection is 250 ° C., the rate of thermal weight loss at 250 ° C. is 5% or less. It is preferable to use an epoxy resin, and 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.

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

[(B) component: curing agent]
Examples of the component (b) include a phenolic resin-based curing agent, an acid anhydride-based curing agent, an amine-based curing agent, an imidazole-based curing agent, and a phosphine-based curing agent. When the component (b) contains a phenolic hydroxyl group, an acid anhydride, an amine or an imidazole, it exhibits a flux activity for suppressing the formation of an oxide film at the connection portion, and can improve connection reliability and insulation reliability. it can. Hereinafter, each curing agent will be described.

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

  The equivalent ratio of the phenolic resin-based curing agent to the component (a) (the number of moles of the phenolic hydroxyl group contained in the phenolic resin-based curing agent / the number of moles of the epoxy group contained in the component (a)) is excellent in curability and adhesiveness. In light of storage stability and storage stability, 0.3 to 1.5 is preferable, 0.4 to 1.0 is more preferable, and 0.5 to 1.0 is still more preferable. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved. When the equivalent ratio is 1.5 or less, the unreacted phenolic hydroxyl group does not remain excessively, and the water absorption is reduced. It tends to be kept low and the insulation reliability tends to improve.

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

  The equivalent ratio of the acid anhydride-based curing agent to the component (a) (the number of moles of the acid anhydride group of the acid anhydride-based curing agent / the number of moles of the epoxy group of the component (a)) is good curability. From the viewpoint of adhesion, storage stability, and the like, 0.3 to 1.5 is preferable, 0.4 to 1.0 is more preferable, and 0.5 to 1.0 is still more preferable. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved. When the equivalent ratio is 1.5 or less, the unreacted acid anhydride does not remain excessively, and the water absorption is reduced. It tends to be kept low and the insulation reliability tends to improve.

(Iii) Amine curing agent As the amine curing agent, for example, dicyandiamide can be used.

  The equivalent ratio of the amine-based curing agent to the component (a) (the number of moles of active hydrogen groups contained in the amine-based curing agent / the number of moles of epoxy groups contained in the component (a)) is excellent in curability, adhesion, and storage. From the viewpoint of stability, 0.3 to 1.5 is preferable, 0.4 to 1.0 is more preferable, and 0.5 to 1.0 is still more preferable. When the equivalent ratio is 0.3 or more, the curability tends to be improved and the adhesive strength tends to be improved. When the equivalent ratio is 1.5 or less, the unreacted amine does not remain excessively and the insulation reliability is improved. Tend to.

(Iv) Imidazole-based curing agent Examples of the imidazole-based curing agent include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1- Cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6 -[2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2, 4-diamino-6- [2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s Triazine, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5- Examples thereof include dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and an adduct of an epoxy resin and imidazoles. Among these, from the viewpoints of excellent curability, storage stability and connection reliability, 1-cyanoethyl-2-undecylimidazole, 1-cyano-2-phenylimidazole, and 1-cyanoethyl-2-undecylimidazole trimellit. Tate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6 [2'-ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl- (1')]-ethyl-s-triazine Isocyanuric acid adduct, 2-phenylimidazole Isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl 4-Methyl-5-hydroxymethylimidazole is preferred. These can be used alone or in combination of two or more. Further, these may be used as a latent curing agent obtained by microencapsulation.

  The content of the imidazole-based curing agent is preferably from 0.1 to 20 parts by mass, more preferably from 0.1 to 10 parts by mass, per 100 parts by mass of the component (a). When the content of the imidazole-based curing agent is 0.1 parts by mass or more, the curability tends to be improved. When the content of the imidazole-based curing agent is 20 parts by mass or less, the fluidity of the first adhesive at the time of pressure bonding can be ensured, and the first adhesive between the connection portions can be sufficiently eliminated. be able to. As a result, since the first adhesive is prevented from being cured while intervening between the solder and the connection portion, a connection failure tends to hardly occur.

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

  The content of the phosphine-based curing agent is preferably from 0.1 to 10 parts by mass, more preferably from 0.1 to 5 parts by mass, per 100 parts by mass of the component (a). When the content of the phosphine-based curing agent is 0.1 part by mass or more, the curability tends to be improved, and when the content is 10 parts by mass or less, the first adhesive is cured before metal bonding is formed. And there is a tendency that poor connection hardly occurs.

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

  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), the first adhesive exhibits a flux activity for removing an oxide film and further improves connection reliability. be able to.

[Component (c): flux compound]
The component (c) is a compound having a flux activity and functions as a flux agent in the first adhesive. As the component (c), a known component can be used without any particular limitation as long as it can reduce the oxide film on the surface such as solder to facilitate metal bonding. As the component (c), one type of flux compound may be used alone, or two or more types of flux compounds may be used in combination. However, the curing agent which is the component (b) is not included in the component (c).

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

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

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

From the viewpoint of excellent reflow resistance and connection reliability, it is preferable that R ¹ has an electron donating property. In the present embodiment, after the first adhesive contains an epoxy resin and a curing agent, among the compounds having a group represented by the formula (1), a compound in which R ¹ is an electron donating group is further added. By containing, even when applied as a film adhesive for a semiconductor in a flip-chip connection method for metal bonding, a semiconductor device having excellent reflow resistance and connection reliability can be manufactured.

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

  Usually, the curing reaction proceeds by the reaction between the epoxy resin and the curing agent. At this time, carboxylic acid as a flux compound is taken into the curing reaction. That is, an ester bond may be formed by the reaction between the epoxy group of the epoxy resin and the carboxyl group of the flux compound. The ester bond is liable to undergo hydrolysis or the like due to moisture absorption, and the decomposition of the ester bond is considered to be a cause of a decrease in adhesive strength after moisture absorption.

On the other hand, among the compounds having a group represented by the formula (1), compounds having a group in which R ¹ is an electron donating group, that is, compounds having a carboxyl group having an electron donating group in the vicinity When carboxyl groups are contained, sufficient flux activity is obtained, and even when the above-described ester bond is formed, the electron-donating group increases the electron density of the ester bond and suppresses the decomposition of the ester bond. Is done. In addition, it is considered that the presence of the substituent (electron-donating group) near the carboxyl group suppresses the reaction between the carboxyl group and the epoxy resin due to steric hindrance, and makes it difficult to form an ester bond.

For these reasons, when the first adhesive further contains a compound in which R ¹ is an electron donating group among the compounds having the group represented by the formula (1), the composition changes due to moisture absorption or the like. Hard and excellent adhesive strength is maintained. In addition, it can be said that the above-mentioned action is that the curing reaction between the epoxy resin and the curing agent is hardly inhibited by the flux compound, and the connection reliability due to the sufficient progress of the curing reaction between the epoxy resin and the curing agent due to this action. The effect of improvement of can be expected.

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

  Examples of the electron donating group include an alkyl group, a hydroxyl group, an amino group, an alkoxy group, and an alkylamino group. As the electron donating group, a group that does not easily react with other components (for example, the epoxy resin of the component (a)) is preferable, and specifically, an alkyl group, a hydroxyl group, or an alkoxy group is preferable, and an alkyl group is more preferable.

  As the alkyl group, an alkyl group having 1 to 10 carbon atoms is preferable, and an alkyl group having 1 to 5 carbon atoms is more preferable. As the carbon number of the alkyl group increases, the electron donating property and the steric hindrance tend to increase. Since an alkyl group having a carbon number in the above range is excellent in the balance between electron donating property and steric hindrance, the effect of the present invention is more remarkably exhibited by the alkyl group.

  Further, 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 equal to or less than the number of carbon atoms in the main chain of the flux compound from the viewpoint of the balance between 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 determined by the carbon number of the main chain of the flux compound ( (n + 1) or less.

  As the alkoxy group, an alkoxy group having 1 to 10 carbon atoms is preferable, and an alkoxy group having 1 to 5 carbon atoms is more preferable. As the carbon number of the alkoxy group increases, the electron donating property and the steric hindrance tend to increase. An alkoxy group having a carbon number in the above range is excellent in the balance between electron donating property and steric hindrance. Therefore, according to the alkoxy group, the effects of the present invention are more remarkably exhibited.

  Further, the alkyl group portion of the alkoxy group may be linear or branched, and is preferably linear. When the alkoxy group is linear, the number of carbon atoms in the alkoxy group is preferably equal to or less than the number of carbon atoms in the main chain of the flux compound from the viewpoint of the balance between 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 alkoxy group, the number of carbon atoms of the alkoxy group is determined by the number of carbon atoms in the main chain of the flux compound ( (n + 1) or less.

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

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

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

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

R ¹ has the same meaning as in formula (1). The electron donating property represented by R ² is the same as the above-described example of the electron donating group described as R ¹ . For the same reason as described in the formula (1), R ¹ in the formula (2) is preferably an electron donating group.

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

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

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

  M in the 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, more excellent connection reliability can be obtained.

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

In the formula (3), if R ¹ and R ² are the same electron-donating group, the structure tends to be symmetrical and the melting point tends to be high. However, 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 less, even when R ¹ and R ² are the same group, the same connection reliability as when R ¹ and R ² are different groups can be obtained. .

  Examples of the flux compound include, for example, dicarboxylic acids selected from succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecandioic acid and dodecanedioic acid, and 2 of these dicarboxylic acids. A compound in which an electron donating group is substituted at the position can be used.

  The melting point of the flux compound is preferably 150 ° C. or lower, more preferably 140 ° C. or lower, even more preferably 130 ° C. or lower. Such a flux compound tends to sufficiently exhibit flux activity before a curing reaction between the epoxy resin and the curing agent occurs. Therefore, according to the film adhesive for semiconductor using the first adhesive containing such a flux compound, a semiconductor device having more excellent connection reliability can be realized. Further, the melting point of the flux compound is preferably at least 25 ° C, more preferably at least 50 ° C. Further, the flux compound is preferably a solid at room temperature (25 ° C.).

  The melting point of the flux compound can be measured using a general melting point measuring device. The sample whose melting point is to be measured is crushed into fine powder, and it is required to reduce the temperature deviation in the sample by using a small amount. As a container for the sample, a capillary tube having one end closed is often used. However, some measuring devices are sandwiched between two microscope cover glasses to form a container. If the temperature is rapidly increased, a temperature gradient will occur between the sample and the thermometer, causing a measurement error. Therefore, the heating at the time of measuring the melting point can be measured at a rate of 1 ° C. or less per minute. desirable.

  Since the material for measuring the melting point is prepared as a fine powder as described above, the sample before melting is opaque due to irregular reflection on the surface. Usually, the temperature at which the appearance of the sample starts to become transparent is defined as the lower limit of the melting point, and the temperature at which the sample is completely melted is defined as the upper limit. There are various types of measuring devices, but the most classical device is a device in which a capillary tube filled with a sample is attached to a double tube thermometer and heated in a warm bath. A highly viscous liquid is used as a hot bath liquid for the purpose of attaching a capillary tube to a double-tube thermometer, and concentrated sulfuric acid or silicon oil is often used, so that the sample comes near the reservoir at the tip of the thermometer. Attach. Further, as the melting point measuring device, a device which heats using a metal heat block and automatically determines the melting point while adjusting the heating while measuring the light transmittance can be used.

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

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

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

  As the component (d), for example, phenoxy resin, polyimide resin, polyamide resin, polycarbodiimide resin, cyanate ester resin, acrylic resin, polyester resin, polyethylene resin, polyether sulfone resin, polyetherimide resin, polyvinyl acetal resin, urethane Resin and acrylic rubber. Among these, phenoxy resins, polyimide resins, acrylic rubbers, cyanate ester resins, and polycarbodiimide resins are preferable, and phenoxy resins, polyimide resins, and acrylic rubbers are more preferable from the viewpoint of excellent heat resistance and film formability. These components (d) can be used alone or as a mixture or copolymer of two or more. However, the component (d) does not include a compound corresponding to the component (a) and a compound corresponding to the component (e).

  The weight average molecular weight of the component (d) is, for example, 10,000 or more, preferably 20,000 or more, and more preferably 30,000 or more. According to the component (d), the heat resistance and the film forming property of the first adhesive can be further improved.

  Further, the weight average molecular weight of the component (d) is preferably 1,000,000 or less, more preferably 500,000 or less. According to such a component (d), the heat resistance of the first adhesive can be further improved.

In addition, in this specification, the weight average molecular weight means a weight average molecular weight when measured in terms of polystyrene using 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 UV Detector (trade name, manufactured by Hitachi, Ltd.)
Pump: L6000 Pump (trade name, manufactured by Hitachi, Ltd.)
Column: Gelpack GL-S300MDT-5 (2 in total) (trade name, manufactured by Hitachi Chemical Co., Ltd.)
Eluent: THF / 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 a component (d), the content ratio _{C a} of the component (a) to the content _{C d} of the component (d) _C a / _{C d} (mass ratio), 0.01 -5, more preferably 0.05-3, even more preferably 0.1-2. By setting the ratio C _a / C _d to 0.01 or more, better curability and adhesion can be obtained, and by setting the ratio C _a / C _d to 5 or less, better film formability can be obtained. .

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

  Examples of the component (e) include an inorganic filler (inorganic particles) and an organic filler (organic particles). Examples of the inorganic filler include insulating inorganic fillers such as glass, silica, alumina, titanium oxide, mica, and boron nitride. Among them, at least one selected from the group consisting of silica, alumina, titanium oxide, and boron nitride is used. Preferably, at least one selected from the group consisting of silica, alumina and boron nitride is more preferable. The insulating inorganic filler may be a whisker. Examples of the whiskers include aluminum borate, aluminum titanate, zinc oxide, calcium silicate, and boron nitride. Examples of the organic filler include a resin filler (resin particles). Examples of the resin filler include polyurethane and polyimide. Resin fillers can provide flexibility at high temperatures such as 260 ° C. as compared with inorganic fillers, so they are suitable for improving reflow resistance, and also capable of imparting flexibility to improve film formability. effective.

  The component (e) is preferably insulative from the viewpoint of further improving insulation reliability. It is preferable that the first adhesive does not contain a conductive metal filler (metal particles) such as a silver filler and a solder filler, and a conductive inorganic filler such as carbon black.

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

  As the surface treatment, a silane treatment with a silane compound such as an epoxy silane type, an amino silane type or an acryl silane type is preferable from the viewpoint of easy surface treatment. As the surface treatment agent, at least one selected from the group consisting of a glycidyl-based compound, a phenylamino-based compound, and a (meth) acryl-based compound is preferable from the viewpoint of excellent dispersibility, fluidity, and adhesion. . As the surface treatment agent, from the viewpoint of excellent storage stability, at least one selected from the group consisting of a phenyl compound and a (meth) acrylic compound is preferable.

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

  The content of the component (e) is determined from the viewpoint that the heat radiation property is suppressed from being lowered and that the generation of voids and the increase in moisture absorption tend to be suppressed from the viewpoint of easily controlling the first adhesive. It is preferably at least 30% by mass, more preferably at least 40% by mass, based on the total amount. As for the content of the component (e), the viscosity is increased, the fluidity of the first adhesive is reduced, and the occurrence of the filler being caught (trapping) in the connection portion is easily suppressed, and the connection reliability is improved. In light of a tendency that the decrease in the property is easily suppressed, the content is preferably 90% by mass or less, more preferably 80% by mass or less based on the total amount of the first adhesive. From these viewpoints, the content of the component (e) is preferably from 30 to 90% by mass, more preferably from 40 to 80% by mass, based on the total amount of the first adhesive.

[Other ingredients]
The first adhesive may contain additives such as an antioxidant, a silane coupling agent, a titanium coupling agent, a leveling agent, and an ion trapping agent. These can be used alone or in combination of two or more. What is necessary is just to adjust suitably these compounding quantities so that the effect of each additive may be exhibited.

(Second adhesive)
The second adhesive is substantially free of the flux compound. “Substantially free” means that the content of the flux compound in the second adhesive is less than 0.5% by mass based on the total amount of the second adhesive.

  The second adhesive preferably has a curing reaction rate of 80% or more when held at 200 ° C. for 5 seconds from the viewpoint that the effects of the present invention are remarkably obtained. Such a second adhesive includes, for example, a radical-curable adhesive. The reason why the effect of the present invention is remarkably obtained by such an adhesive is not clear, but the present inventors speculate as follows.

  That is, in a film adhesive containing a conventional flux compound, a radical curing system cannot be applied because a flux component inactivates radicals, and a cationic curing system using an epoxy or the like is applied. There were many things. In this curing system (reaction system), the curing progresses by a nucleophilic addition reaction, so that the curing speed is slow, and voids may be generated after pressure bonding. It is presumed that in the conventional film adhesive, a defect (for example, peeling of the semiconductor material at a reflow temperature of about 260 ° C., poor connection of the connection portion, or the like) occurred due to the void at the time of mounting. On the other hand, since the second adhesive described above does not substantially contain a flux compound, the curing system can be a radical curing system, and a sufficient curing speed can be obtained. Therefore, it is presumed that the use of the above-mentioned second adhesive for the second layer makes it difficult for voids to be generated even when pressure bonding is performed at a high temperature and for a short time, and the effect of the present invention becomes remarkable. You. Further, in the present embodiment, since a sufficient curing speed can be obtained, for example, even when solder is used in the connection portion, the film adhesive is cured in a temperature region lower than the solder melting temperature. Can be done. Therefore, it is possible to sufficiently suppress the occurrence of the connection failure due to the scattering and flow of the solder.

  Hereinafter, the second adhesive needs a radical polymerizable compound (hereinafter sometimes referred to as “component (A)”) and a thermal radical generator (hereinafter sometimes referred to as “component (B)”). An embodiment will be described that contains a polymer component (hereinafter, sometimes referred to as a “component (C)”) and a filler (hereinafter, sometimes referred to as a “component (D)”), depending on the conditions.

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

  The component (A) preferably has a bisphenol A type skeleton, a bisphenol F type skeleton, a naphthalene type skeleton, a fluorene type skeleton, an adamantane type skeleton or an isocyanuric acid type skeleton from the viewpoint of excellent heat resistance, and has a fluorene type skeleton. Is more preferable. The component (A) is more preferably a (meth) acrylate having any of the above-described skeletons.

  The component (A) is preferably solid at room temperature (25 ° C.). Solids are less likely to generate voids than liquids, and have a small viscosity (tack) of the second adhesive before curing (B stage) and are excellent in handleability. Examples of the component (A) which is solid at room temperature (25 ° C.) include a (meth) acrylate having a bisphenol A type skeleton, a fluorene type skeleton, an adamantane type skeleton, or an isocyanuric acid type skeleton.

  The number of functional groups of the (meth) acryl group in the component (A) is preferably 3 or less. When the number of functional groups is large, the curing network proceeds rapidly, and unreacted groups may remain. On the other hand, when the number of functional groups is 3 or less, the number of functional groups does not become too large, and curing in a short time is apt to proceed sufficiently, so that a decrease in the curing reaction rate is easily suppressed.

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

  The content of the component (A) is 10% by mass or more based on the total amount of the second adhesive from the viewpoint that the amount of the curing component is suppressed from being reduced and the flow of the resin after curing is easily controlled sufficiently. Preferably, the content is 15% by mass or more. The content of the component (A) is 50 mass% based on the total amount of the second adhesive, from the viewpoint that the cured product is suppressed from becoming too hard, and the warpage of the package tends to be suppressed. % Or less, more preferably 40% by mass or less. From these viewpoints, the content of the component (A) is preferably from 10 to 50% by mass, and more preferably from 15 to 40% by mass, based on the total amount of the second adhesive.

  The content of the component (A) is preferably at least 0.01 part by mass with respect to 1 part by mass of the component (C), from the viewpoint that the curability is suppressed from decreasing and the adhesive strength is easily suppressed from decreasing. Preferably, it is 0.05 parts by mass or more, more preferably 0.1 parts by mass or more. The content of the component (A) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, based on 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 more preferably from 0.1 to 5 parts by mass, per 1 part by mass of the component (C). 5 parts by mass is more preferred.

[(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 generator from the viewpoint of excellent handleability.

  Examples of the thermal radical generator include azo compounds and peroxides (such as organic peroxides). As the thermal radical generator, a peroxide is preferable, and an organic peroxide is more preferable. In this case, the radical reaction does not progress in the step of drying the solvent when forming the film, and the film is excellent in handleability and storage stability. Therefore, when a peroxide is used as the thermal radical generator, more excellent connection reliability is easily obtained. Examples of the organic peroxide include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate, and peroxyester. As the organic peroxide, from the viewpoint of excellent storage stability, at least one selected from the group consisting of hydroperoxides, dialkyl peroxides and peroxyesters is preferable. Furthermore, as the organic peroxide, from the viewpoint of excellent heat resistance, at least one selected from the group consisting of hydroperoxides and dialkyl peroxides is preferable. Examples of the dialkyl peroxide include dicumyl peroxide and di-tert-butyl peroxide.

  The content of the component (B) is preferably at least 0.5 part by mass, more preferably at least 1 part by mass, based on 100 parts by mass of the component (A), from the viewpoint that curing can easily proceed sufficiently. The content of the component (B) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, based on 100 parts by mass of the component (A). When the upper limit of the content of the component (B) is within the above range, the curing proceeds rapidly and the number of reaction points is suppressed from being increased, so that the molecular chain is shortened and unreacted groups are reduced. The remaining is suppressed. Therefore, when the upper limit of the content of the component (B) is in the above range, a decrease in reliability tends to be easily suppressed. From these viewpoints, the content of the component (B) is preferably from 0.5 to 10 parts by mass, more preferably from 1 to 5 parts by mass, per 100 parts by mass of the component (A).

[Component (C): polymer component]
The second adhesive may further contain a polymer component. The component (C) includes an epoxy resin, a phenoxy resin, a polyimide resin, a polyamide resin, a polycarbodiimide resin, a cyanate ester resin, a (meth) acrylic resin, a polyester resin, a polyethylene resin, a polyether sulfone resin, a polyetherimide resin, and a polyvinyl acetal. Resins, urethane resins, acrylic rubbers, etc., among which epoxy resins, phenoxy resins, polyimide resins, (meth) acrylic resins, acrylic rubbers, cyanate ester resins, and polycarbodiimides from the viewpoint of excellent heat resistance and film formability. At least one selected from the group consisting of resins is preferred, and at least one selected from the group consisting of epoxy resins, phenoxy resins, polyimide resins, (meth) acrylic resins and acrylic rubbers is more preferred. The component (C) can be used alone or as a mixture or copolymer of two or more. However, the compound corresponding to the component (A) and the compound corresponding to the component (D) are not included in the component (C).

  The glass transition temperature (Tg) of the component (C) is preferably 120 ° C. or lower, more preferably 100 ° C. or lower, and further preferably 85 ° C. or lower, from the viewpoint of excellent adhesion of the film adhesive for semiconductor to a substrate or chip. preferable. When the thickness is within these ranges, the bumps formed on the semiconductor chip, the electrodes or the wiring patterns formed on the substrate, or the like can be easily embedded with the film adhesive for semiconductor (the curing reaction starts). Tend to suppress the occurrence of voids due to remaining air bubbles. The Tg is a Tg measured using a DSC (manufactured by PerkinElmer, trade name: DSC-7 type) under the conditions of a sample amount of 10 mg, a heating rate of 10 ° C./min, and a measurement atmosphere of air. It is.

  The weight average molecular weight of the component (C) is preferably 10,000 or more in terms of polystyrene, more preferably 30,000 or more, still more preferably 40,000 or more, and particularly preferably 50,000 or more, in order to show good film-forming properties by itself. When the weight average molecular weight is 10,000 or more, there is a tendency that a decrease in film formability is easily suppressed.

[(D) component: filler]
The second adhesive has a filler for controlling the viscosity or physical properties of the cured product, and for further suppressing the generation of voids or the moisture absorption when the semiconductor chip and the substrate or the semiconductor chips are connected to each other. Further, it may be contained. As the component (D), the same filler as the filler exemplified as the component (d) in the first adhesive can be used. The same applies to preferred fillers.

  The content of the component (D) is determined from the viewpoint that the heat dissipation is suppressed from being lowered, and that the generation of voids and the increase in moisture absorption tend to be suppressed. It is preferably at least 30% by mass, more preferably at least 40% by mass, based on the total amount. As for the content of the component (D), the viscosity is increased and the fluidity of the second adhesive is reduced, and the occurrence of the filler being trapped (trapping) in the connection portion is easily suppressed, and the connection reliability is reduced. From the viewpoint of the tendency that the decrease in the property tends to be suppressed, the amount is preferably 90% by mass or less, more preferably 80% by mass or less based on the total amount of the second adhesive. From these viewpoints, the content of the component (D) is preferably from 30 to 90% by mass, more preferably from 40 to 80% by mass, based on the total amount of the second adhesive.

[Other ingredients]
A polymerizable compound other than the radical polymerizable compound (for example, a cationic polymerizable compound and an anionic polymerizable compound) may be blended in the second adhesive. Further, other components similar to those of the first adhesive may be blended in the second adhesive. These can be used alone or in combination of two or more. What is necessary is just to adjust suitably these compounding quantities so that the effect of each additive may be exhibited.

The curing reaction rate when the second adhesive is held at 200 ° C. for 5 seconds is preferably 80% or more, and more preferably 90% or more. If the curing reaction rate at 200 ° C. (less than the solder melting temperature) / 5 seconds is 80% or more, it is easy to prevent the solder from scattering and flowing at the time of connection (more than the solder melting temperature) and lowering the connection reliability. The curing reaction rate was determined by measuring the calorific value using DSC (trade name: DSC-7 type, manufactured by PerkinElmer) after putting 10 mg of the second adhesive (uncured flux-free layer) into an aluminum pan. Can be obtained. Specifically, a measurement sample in which 10 mg of the second adhesive (uncured flux-free layer) was placed in an aluminum pan was placed on a hot plate heated to 200 ° C., and after 5 seconds, the measurement sample was placed on the hot plate. Remove. The measurement sample after the heat treatment and the untreated measurement sample are each measured by DSC. From the obtained calorific value, the curing reaction rate is calculated by the following equation.
Curing reaction rate (%) = (1− [calorific value of measurement sample after heat treatment] / [calorific value of untreated measurement sample]) × 100

  When the second resin contains an anionic polymerizable epoxy resin (particularly, an epoxy resin having a weight average molecular weight of 10,000 or more), it may be difficult to adjust the curing reaction rate to 80% or more. The content of the epoxy resin is preferably 20 parts by mass or less based on 80 parts by mass of the component (A), and more preferably no epoxy resin is contained.

  The second layer (flux-free layer) made of the second adhesive can be press-bonded at a high temperature of 200 ° C. or higher. Further, in a flip chip package in which a connection is formed by melting a metal such as solder, more excellent curability is exhibited.

  Regarding the thickness of the film adhesive for semiconductor of the present embodiment, when the sum of the heights of the above-mentioned connecting portions is x and the total thickness of the film adhesive for semiconductor is y, the relationship between x and y is as follows. From the viewpoint of the connectivity at the time of pressure bonding and the filling property of the adhesive, it is preferable to satisfy 0.70x ≦ y ≦ 1.3x, more preferably 0.80x ≦ y ≦ 1.2x. The total thickness of the film adhesive for semiconductors may be, for example, 10 to 100 μm, 10 to 80 μm, or 10 to 50 μm.

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

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

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

  The film adhesive for semiconductor of the present embodiment may further include other layers than the first layer and the second layer, but preferably includes only the first layer and the second layer. . In addition, the film adhesive for a semiconductor of the present embodiment is provided on the surface of the first layer opposite to the second layer and / or the surface of the second layer opposite to the first layer. A base film and / or a protective film may be provided thereon.

<Production method of film adhesive for semiconductor>
The film adhesive for a semiconductor according to the present embodiment includes, for example, a first film adhesive having a first layer and a second film adhesive having a second layer. It can be obtained by laminating a first film adhesive having a layer and a second film adhesive having a second layer.

  In the step of preparing the first film adhesive, for example, first, the component (a), the component (b) and the component (c), and the component (d) and the component (e) added as necessary. The other components are added to an organic solvent and dissolved or dispersed by stirring, mixing, kneading or the like to prepare a resin varnish (coating varnish). Then, after applying a resin varnish to the release-treated base film using a knife coater, a roll coater, an applicator, or the like, the organic solvent is reduced by heating, and the first adhesion is performed on the base film. A first layer of the agent can be formed.

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

  The substrate film is not particularly limited as long as it has heat resistance enough to withstand the heating conditions when the organic solvent is volatilized.Polyolefin films such as polypropylene films and polymethylpentene films, polyethylene terephthalate films, polyethylene naphthalate Examples thereof include a polyester film such as a film, a polyimide film, and a polyetherimide film. The base film is not limited to a single-layer film composed of these films, and may be a multilayer film composed of two or more materials.

  The drying conditions when the organic solvent is volatilized from the resin varnish applied to the base film is preferably set to a condition where the organic solvent is sufficiently volatilized, specifically, 50 to 200 ° C. for 0.1 to 90 minutes. Is preferably performed. The organic solvent is preferably removed to 1.5% by mass or less with respect to the total amount of the first film adhesive as long as the void or the viscosity adjustment after mounting is not affected.

  In the step of preparing the second film adhesive, the first layer is prepared except that the components (A) and (B), and other components (C) added as necessary. The second layer made of the second adhesive can be formed on the base film by the same method as described above.

  Examples of a method of bonding the first film-like adhesive and the second film-like adhesive include a method such as a heat press, a roll lamination, and a vacuum lamination. Lamination may be performed, for example, under a heating condition of 30 to 120 ° C.

  The film adhesive for semiconductor of the present embodiment, for example, after forming one of the first layer or the second layer on the base film, on the obtained first layer or the second layer, It may be obtained by forming the other of the first layer and the second layer. The first layer and the second layer may be formed by a method similar to the method of forming the first layer and the second layer in the production of the film-form adhesive with a base described above.

<Semiconductor device>
The semiconductor device according to the present embodiment will be described below with reference to FIGS. FIG. 1 is a schematic sectional view showing one embodiment of the semiconductor device of the present invention. As shown in FIG. 1A, a semiconductor device 100 includes a semiconductor chip 10 and a substrate (circuit wiring substrate) 20 facing each other, and a wiring 15 arranged on the surfaces of the semiconductor chip 10 and the substrate 20 facing each other. A connection bump 30 for connecting the semiconductor chip 10 and the wiring 15 of the substrate 20 to each other, and an adhesive (a first adhesive and a second adhesive) filled in the gap between the semiconductor chip 10 and the substrate 20 without any gap. And a sealing portion 40 made of a cured product. The semiconductor chip 10 and the substrate 20 are flip-chip connected by the wiring 15 and the connection bump 30. The wiring 15 and the connection bump 30 are sealed with a cured product of an adhesive and are shielded from an external environment. The sealing section 40 has an upper portion 40a containing a cured product of the first adhesive and a lower portion 40b containing a cured product of the second adhesive.

  As shown in FIG. 1B, the semiconductor device 200 includes a semiconductor chip 10 and a substrate 20 facing each other, bumps 32 respectively arranged on surfaces of the semiconductor chip 10 and the substrate 20 facing each other, A sealing portion 40 made of a cured product of an adhesive (a first adhesive and a second adhesive) filled into the gaps between the substrates 20 without any gap. The semiconductor chip 10 and the substrate 20 are flip-chip connected by connecting the opposing bumps 32 to each other. The bump 32 is sealed with a cured product of an adhesive and is shielded from an external environment. The sealing section 40 has an upper portion 40a containing a cured product of the first adhesive and a lower portion 40b containing a cured product of the second adhesive.

  FIG. 2 is a schematic sectional view showing another embodiment of the semiconductor device of the present invention. As shown in FIG. 2A, the semiconductor device 300 is the same as the semiconductor device 100 except that two semiconductor chips 10 are flip-chip connected by wirings 15 and connection bumps 30. As shown in FIG. 2B, the semiconductor device 400 is similar to the semiconductor device 200 except that two semiconductor chips 10 are flip-chip connected by bumps 32.

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

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

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

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

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

  Further, the semiconductor device of the present embodiment may have a plurality of stacked structures (packages) as shown in the semiconductor devices 100 to 400. In this case, the semiconductor devices 100 to 400 are made of gold, silver, copper, solder (for example, tin-silver, tin-lead, tin-bismuth, tin-copper, tin-silver-copper, etc.), tin, nickel They may be electrically connected to each other by bumps, wirings, or the like including these.

  As a technique for stacking a plurality of semiconductor devices, for example, a TSV (Through-Silicon Via) technique can be given as shown in FIG. FIG. 3 is a schematic sectional view showing another embodiment of the semiconductor device of the present invention, which is a semiconductor device using the TSV technology. In the semiconductor device 500 shown in FIG. 3, the wiring 15 formed on the interposer 50 is connected to the wiring 15 of the semiconductor chip 10 via the connection bumps 30, so that the semiconductor chip 10 and the interposer 50 are flip-chip connected. ing. The space between the semiconductor chip 10 and the interposer 50 is filled with a cured product of an adhesive (a first adhesive and a second adhesive) without gaps, and forms a sealing portion 40. On the surface of the semiconductor chip 10 opposite to the interposer 50, the semiconductor chip 10 is repeatedly laminated via the wiring 15, the connection bump 30, and the sealing portion 40. The wirings 15 on the pattern surface on the front and back sides of the semiconductor chip 10 are connected to each other by through electrodes 34 filled in holes passing through the inside of the semiconductor chip 10. The material of the through electrode 34 may be copper, aluminum, or the like.

  With such a TSV technology, it is possible to acquire signals even from the back surface of a semiconductor chip that is not normally used. Furthermore, since the penetrating electrodes 34 pass vertically through the semiconductor chip 10, the distance between the opposing semiconductor chips 10 and the distance between the semiconductor chip 10 and the interposer 50 can be shortened, and flexible connection is possible. The film adhesive for semiconductor of the present embodiment can be applied as a film adhesive for semiconductor between the opposed semiconductor chips 10 and between the semiconductor chip 10 and the interposer 50 in such TSV technology.

  In a bump forming method with a high degree of freedom, such as an area bump chip technique, a semiconductor chip can be directly mounted on a motherboard without an interposer. The film adhesive for semiconductor of the present embodiment can be applied to a case where such a semiconductor chip is directly mounted on a motherboard. In addition, the film adhesive for semiconductors of the present embodiment can be applied to a case where two printed circuit boards are laminated and a gap between the substrates is sealed.

<Semiconductor device manufacturing method>
The method for manufacturing the semiconductor device according to the present embodiment will be described below with reference to FIG. 4A to 4C are diagrams schematically showing one embodiment of a method for manufacturing a semiconductor device according to the present invention. FIGS. 4A, 4B, and 4C showing each step are shown in FIGS. 2 shows a cross section of FIG.

  First, as shown in FIG. 4A, a solder resist 60 having an opening at a position where the connection bump 30 is to be formed is formed on the substrate 20 having the wiring 15. This solder resist 60 does not necessarily need to be provided. However, by providing the solder resist on the substrate 20, the occurrence of bridges between the wirings 15 can be suppressed, and the 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 a package. Specific examples of commercially available solder resist inks for packaging include SR series (trade name, manufactured by Hitachi Chemical Co., Ltd.) and PSR4000-AUS series (trade name, manufactured by Taiyo Ink Mfg. Co., Ltd.).

  Next, as shown in FIG. 4A, connection bumps 30 are formed in the openings of the solder resist 60. Then, as shown in FIG. 4B, the surface on the second layer 41b side including the second adhesive is on the substrate 20 side on the substrate 20 on which the connection bumps 30 and the solder resist 60 are formed. Then, the film adhesive for semiconductor (hereinafter, sometimes referred to as “film adhesive”) 41 of the present embodiment is attached to the adhesive. The attachment of the film adhesive 41 can be performed by hot press, roll lamination, vacuum lamination, or the like. The supply area and the thickness of the film adhesive 41 are appropriately set according to the size of the semiconductor chip 10 and the substrate 20, the height of the connection bump 30, and the like. The film adhesive 41 may be attached such that the surface on the first layer 41a side including the first adhesive is on the substrate 20 side.

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

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

  In the method for manufacturing a semiconductor device according to the present embodiment, the connection bump 30 is melted by performing a heat treatment in a reflow furnace by temporarily fixing after the alignment (with the film-like adhesive for a semiconductor interposed therebetween) and by performing a heat treatment in a reflow furnace. The chip 10 and the substrate 20 may be connected. At the temporary fixing stage, it is not always necessary to form a metal joint. Therefore, compared to the above-mentioned method of crimping while heating, crimping with a low load, a short time, and a low temperature is sufficient, thereby improving productivity and connecting. Deterioration of the part can be suppressed.

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

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

  From the viewpoint of improving productivity, a semiconductor film-like adhesive is supplied to a semiconductor wafer to which a plurality of semiconductor chips 10 are connected, and then diced into individual pieces, thereby bonding the semiconductor film-like adhesive onto the semiconductor chip 10. A structure to which the agent has been supplied may be obtained. The film adhesive for semiconductor may be supplied so as to embed the wirings, bumps, and the like on the semiconductor chip 10 by a bonding method such as hot press, roll lamination, and vacuum lamination. In this case, since the supply amount of the resin is constant, productivity is improved, and it is possible to suppress generation of voids and reduction in dicing performance due to insufficient embedding.

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

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

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

  As described above, the preferred embodiments of the present invention have been described, but the present invention is not limited to the above embodiments.

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

<Preparation of single-layer film with flux-containing layer>
The compounds used for producing the single-layer film having the flux-containing layer are shown below.
(A) Epoxy resin, triphenolmethane skeleton-containing polyfunctional solid epoxy ("EP1032H60", manufactured by Japan Epoxy Resin Co., Ltd.)
-Bisphenol F type liquid epoxy (manufactured by Japan Epoxy Resin Co., Ltd., trade name "YL983U")
(B) Curing agent • 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine isocyanuric acid adduct (trade name “2MAOK-PW” manufactured by Shikoku Chemicals Co., Ltd.) )
(C) Flux agent / glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd., melting point: about 98 ° C.)
・ 2-methylglutaric acid (Aldrich, melting point about 78 ° C)
・ 3-methylglutaric acid (Tokyo Kasei Co., Ltd., melting point: about 87 ° C)
(D) Polymer component / phenoxy resin (trade name “ZX1355-2”, manufactured by Toto Kasei Co., Ltd., Tg: about 71 ° C., weight average molecular weight Mw: about 63000)
(E) Filler / silica filler (Admatex Co., Ltd., SE2050, average particle size: 0.5 μm)
・ Epoxysilane surface treated filler (Admatex Co., Ltd., SE2050-SEJ, average particle size: 0.5 μm)
-Methacryl surface-treated nano silica filler (Admatex, YA050C-MJE, average particle size: about 50 nm)
-Organic filler (resin filler, manufactured by Rohm and Haas Japan K.K., EXL-2655: core-shell type organic fine particles)

  An epoxy resin, a curing agent, a fluxing agent, an inorganic filler, and an organic filler having the compounding amount (unit: parts by mass) shown in Table 1 were subjected to NV value ([paint mass after drying] / [paint mass before drying]) × 100) was added to an organic solvent (methyl ethyl ketone) so as to be 60%. Thereafter, Φ1.0 mm beads and Φ2.0 mm beads were added in the same mass as the solid content (epoxy resin, curing agent, fluxing agent, polymer component, inorganic filler and organic filler), and a bead mill (Fritsch Japan Co., Ltd., The mixture was stirred for 30 minutes with a planetary pulverizer P-7). After stirring, the beads were removed by filtration to produce a coating varnish.

  The obtained coating varnish is coated on a base film (manufactured by Teijin Dupont Co., Ltd., trade name "Purex A54") using a small precision coating apparatus (Narii Seiki) and a clean oven (ESPEC) ) And dried (80 ° C./10 min) to obtain single-layer films (A-1), (A-2) and (A-3) shown in Table 1.

<Preparation of single-layer film with flux-free layer>
The compounds used for producing a single-layer film having a flux-free layer are shown below.

(A) (meth) acrylic compound-Acrylate having a fluorene-type skeleton (Osaka Gas Chemical Co., Ltd., EA-0200, bifunctional group)
Acrylate having bisphenol A type skeleton (Shin Nakamura Chemical Co., Ltd., EA1020)
-Ethoxylated isocyanuric acid triacrylate (Shin-Nakamura Chemical Co., Ltd., A-9300)

(B) Thermal radical generator dicumyl peroxide (NOF Corporation, Parkmill (registered trademark) D)
-Di-tert-butyl peroxide (NOV CORPORATION, Perbutyl (registered trademark) D)
-1,4-bis-((tert-butylperoxy) diisopropyl) benzene (NOV CORPORATION, Perbutyl (registered trademark) P)

(C) Polymer component-Acrylic resin (Hitachi Chemical Co., Ltd., KH-CT-865, weight average molecular weight Mw: 100,000, Tg: 10 ° C)

(D) Filler The same filler as the filler (component (d)) used for producing the single-layer film having the flux-containing layer was used.

  The (meth) acrylic compound, the polymer component, the inorganic filler and the organic filler in the compounding amounts (unit: parts by mass) shown in Table 2 were added to the organic solvent (methyl ethyl ketone) so that the NV value became 60%. Thereafter, beads having a diameter of 1.0 mm and beads having a diameter of 2.0 mm were added in the same mass as the solid content ((meth) acrylic compound, polymer component, inorganic filler and organic filler), and a bead mill (Fritsch Japan Co., Ltd., planetary type fine) was added. The mixture was stirred for 30 minutes with a pulverizer P-7). After stirring, the beads were removed by filtration. Next, a thermal radical generator was added to the obtained mixture, followed by stirring and mixing to prepare a coating varnish.

  The obtained coating varnish is coated on a base film (manufactured by Teijin Dupont Film Co., Ltd., trade name "Purex A54") using a small precision coating device (Narii Seiki) and a clean oven (ESPEC) ) And dried (80 ° C./10 min) to obtain single-layer films (B-1), (B-2), (B-3), (B-4) and (B-5) shown in Table 2. Was.

<Preparation of two-layer film>
(Examples 1 and 2, and Comparative Examples 1 to 8)
Two of the single-layer films prepared above (first film and second film) were laminated at 50 ° C. to prepare a film-like adhesive having a total thickness of 40 μm. The combinations of the single-layer films were as shown in Table 3.

<Evaluation>
The initial adhesiveness evaluation, void evaluation, solder wettability evaluation, and insulation reliability evaluation of the film adhesives obtained in Examples and Comparative Examples were performed by the methods described below. Table 3 shows the results.

(Evaluation of initial connectivity)
The film adhesive prepared in the example or the comparative example was cut into a predetermined size (8 mm long × 8 mm wide × 40 μm thick) to prepare a sample for evaluation. Next, the evaluation sample was attached on a glass epoxy substrate (glass epoxy substrate: 420 μm thickness, copper wiring: 9 μm thickness), and a semiconductor chip with solder bumps (chip size: 7.3 mm long × 7.3 mm wide × thickness) 0.15 mm, bump height: copper pillar + solder about 40 μm, bump number 328) were mounted by flip mounting apparatus “FCB3” (trade name, manufactured by Panasonic) (mounting conditions: crimping head temperature 350 ° C., crimping time 3). Second, compression pressure 0.5 MPa). Thus, a semiconductor device in which the glass epoxy substrate and the semiconductor chip with solder bumps were daisy-chain-connected was manufactured as in FIG. The evaluation samples of Examples 1 and 2 were attached on a glass substrate such that the flux-free layer and the glass epoxy substrate were in contact with each other.

  The initial continuity after mounting was evaluated by measuring the connection resistance value of the obtained semiconductor device using a multimeter (trade name “R6871E” manufactured by ADVANTEST). When the connection resistance is 10.0Ω or more and 13.5Ω or less, the connection is “A” (good). When the connection resistance is more than 13.5Ω and 20Ω or less, the connection is “B” (bad). When the resistance value was greater than 20Ω, when the connection resistance value was less than 10Ω, and when the resistance value was not displayed due to poor connection, all were evaluated as connectivity “C” (defective).

(Void evaluation)
With respect to the semiconductor device manufactured by the above-described method, an external appearance image is taken by an ultrasonic diagnostic imaging device (trade name “Insight-300”, manufactured by Insight), and the chip is scanned on a chip by a scanner GT-9300UF (trade name, manufactured by EPSON). An image of the adhesive layer (a layer composed of a cured product of a film adhesive for a semiconductor) is captured, and void portions are identified by color tone correction and two-gradation using image processing software Adobe Photoshop (registered trademark), and a histogram is used. The proportion of the void portion was calculated. Assuming that the area of the adhesive portion on the chip is 100%, "A" indicates that the void generation rate is 5% or less, "B" indicates that the void generation rate is more than 5% and 10% or less, and "B" indicates that the void generation rate is more than 10%. C ".

(Solder wettability evaluation)
Regarding the semiconductor device manufactured by the above method, the cross section of the connection portion was observed, and the case where 90% or more of the solder was wet on the upper surface of the Cu wiring was "A" (good), and the case where the solder wetness was less than 90%. It was evaluated as "B" (insufficient wetting).

(Insulation reliability test [HAST test: Highly Accelerated Storage Test])
The film-like adhesive (thickness: 40 μm) produced in the example or the comparative example was affixed to a comb-shaped electrode evaluation TEG (manufactured by Hitachi Chemical Co., Ltd., wiring pitch: 50 μm), and placed in a clean oven (manufactured by ESPEC). Cure at ° C for 2 hours. The cured sample was placed in an accelerated life tester (trade name: “PL-422R8”, manufactured by HIRAYAMA, condition: 130 ° C./85% RH / 100 hours, 5 V applied), and the insulation resistance was measured. “A” indicates that the insulation resistance after 10 hours was 10 ⁸ Ω or more, and “B” indicates that the insulation resistance was 10 ⁷ Ω or more and less than 10 ⁸ Ω, and “C” indicates that the insulation resistance was less than 10 ⁷ Ω. Was evaluated.

  It was confirmed that the film adhesives for semiconductors of Examples 1 and 2 sufficiently suppressed the generation of voids, had good solder wettability, and had excellent HAST resistance.

  DESCRIPTION OF SYMBOLS 10 ... Semiconductor chip, 15 ... Wiring (connection part), 20 ... Substrate (wiring circuit board), 30 ... Connection bump, 32 ... Bump (connection part), 34 ... Through-electrode, 40 ... Sealing part, 41 ... For semiconductor Film adhesive, 50 interposer, 60 solder resist, 100, 200, 300, 400, 500, 600 semiconductor device.

Claims (12)

A first layer comprising a first adhesive containing a flux compound;
A second layer made of a second adhesive that is provided on the first layer and that does not substantially contain a flux compound.   The film adhesive for semiconductors according to claim 1, wherein the second adhesive has a curing reaction rate of 80% or more when held at 200 ° C for 5 seconds.   The film adhesive for semiconductors according to claim 1, wherein the second adhesive contains a radical polymerizable compound and a thermal radical generator.   The film adhesive for semiconductor according to claim 3, wherein the thermal radical generator is a peroxide.   The film adhesive for semiconductors according to claim 3 or 4, wherein the radical polymerizable compound is a (meth) acrylic compound.   The film adhesive for a semiconductor according to claim 5, wherein the (meth) acrylic compound has a fluorene-type skeleton.   The film adhesive for a semiconductor according to any one of claims 1 to 6, wherein the flux compound has a carboxyl group.   The film adhesive for a semiconductor according to any one of claims 1 to 7, wherein the flux compound has two or more carboxyl groups. The film adhesive for semiconductors according to any one of claims 1 to 8, wherein the flux compound is a compound represented by the following formula (2).

[In the formula (2), R ¹ and R ² each independently represent a hydrogen atom or an electron donating group, and n represents 0 or an integer of 1 or more. ]   The film adhesive for a semiconductor according to claim 1, wherein the flux compound has a melting point of 150 ° C. or less. A method of manufacturing a semiconductor device in which connection portions of a semiconductor chip and a wiring 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,
A method for manufacturing a semiconductor device, comprising a step of sealing at least a part of the connection part using the film adhesive for a semiconductor according to claim 1. A semiconductor device in which respective connection portions of the semiconductor chip and the wiring circuit board are electrically connected to each other, or a semiconductor device in which respective connection portions of a plurality of semiconductor chips are electrically connected to each other,
A semiconductor device, wherein at least a part of the connection portion is sealed with a cured product of the film adhesive for a semiconductor according to any one of claims 1 to 10.

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