JP5381775B2 - Conductive connection sheet, connection method between terminals, formation method of connection terminal, semiconductor device and electronic device - Google Patents

Description

  The present invention relates to a conductive connection sheet, a connection method between terminals, a method for forming a connection terminal, a semiconductor device, and an electronic apparatus.

  In recent years, along with the demand for higher functionality and miniaturization of electronic equipment, the pitch between connection terminals in electronic materials is becoming increasingly narrow, and the connection between terminals in a fine wiring circuit is also becoming more sophisticated.

  As the inter-terminal connection method, for example, a flip chip connection technique in which a large number of terminals are collectively connected using an anisotropic conductive adhesive or an anisotropic conductive film when an IC chip is electrically connected to a circuit board. It has been known. Such an anisotropic conductive adhesive or anisotropic conductive film is a film or paste in which conductive particles are dispersed in an adhesive mainly composed of a thermosetting resin, and the electronic member to be connected thereto By disposing them in between and thermocompression bonding, a large number of opposing terminals can be connected together, while insulation between adjacent terminals can be ensured by the resin in the adhesive.

  However, in the anisotropic conductive adhesive or anisotropic conductive film, it is difficult to control the aggregation of the conductive particles, and the conductive particles and the terminals or the conductive particles face each other without sufficiently contacting each other. Some of the terminals do not conduct, or conductive particles remain in the resin (insulating region) other than between the opposing terminals (conducting region), and insulation between adjacent terminals is not sufficiently secured. There was a problem. For this reason, it was difficult to cope with further narrowing of the pitch between terminals.

  On the other hand, when manufacturing a connection terminal on an electronic member, conventionally, a solder paste is printed on a substrate provided with a metal pad, and the solder paste is heated and melted using a solder reflow apparatus or the like. However, in this method, when the connection terminals have a narrow pitch, the cost of the mask used when printing the solder paste increases, and if the connection terminals are small, printing may not be possible.

  Also, in the method in which solder balls are mounted on the connection terminals and the solder balls are heated and melted using a solder reflow device or the like, if the connection terminals are small, the manufacturing cost of the solder balls increases, and the solder balls having a small diameter In some cases, it was technically difficult to fabricate.

JP-A 61-276873 JP 2004-260131 A

  In order to solve such problems, a conductive connection sheet composed of a laminate including a resin composition layer containing a curable resin component and a metal layer composed of a low melting point metal material has been studied. ing.

  When the low-melting-point metal material is heated at a temperature equal to or higher than the melting point in a state where the conductive connection sheet having such a configuration is disposed between the facing terminals, the molten metal material selectively aggregates between the facing terminals, In addition, since the region other than between the terminals is filled with a curable resin component, it can be connected with a connecting portion made of a metal material that selectively aggregates a large number of opposing terminals together, Furthermore, the insulation between adjacent terminals is ensured by the curable resin component contained in the resin composition.

  However, when the water absorption rate of the resin composition layer before curing is high, that is, when the amount of water contained in the resin composition layer before curing is high, the oxidation on the surface of the metal layer proceeds remarkably. The cohesive force of the low melting point metal material in the molten state between the terminals is reduced, or voids are generated when the resin composition filled in the region excluding the terminals is cured. Therefore, it has been found that sufficient insulation between adjacent terminals cannot be ensured. Furthermore, when the water absorption rate of the cured resin composition layer is high, that is, when the amount of water contained in the cured resin composition layer is high, a leak current is generated during the HAST test (Highly Accelerated Temperature and Humidity Stress Test). Therefore, the problem that the insulation reliability of a semiconductor device or electronic device provided with the connection part formed using this electrically conductive connection sheet falls arises.

  Accordingly, an object of the present invention is to reduce the occurrence of leakage current between adjacent terminals due to the formation of an oxide film on the surface of the metal layer and the generation of voids in the curable resin component. An object of the present invention is to provide a conductive connection sheet excellent in HAST resistance of a device, a connection method between terminals using the conductive connection sheet, a method of forming a connection terminal, a highly reliable semiconductor device, and an electronic device.

Such an object is achieved by the present invention described in the following (1) to (16).
(1) A conductive connection sheet comprising a laminate comprising a resin composition layer containing a curable resin component and a metal layer composed of a low melting point metal material,
The water absorption before curing of the resin composition layer is more than 0.0% and 1.2% or less, and the water absorption after curing is more than 0.0% and 2.5% or less. Conductive connection sheet.

  (2) The conductive connection sheet according to (1), wherein the resin composition layer includes a resin composition containing the curable resin component and a compound having a flux function.

  (3) The conductive connection sheet according to (2), wherein the compound having the flux function includes a compound having at least one of a phenolic hydroxyl group and a carboxyl group.

(4) The conductive connection sheet according to (2) or (3), wherein the compound having the flux function includes a compound represented by the following general formula (1).
_{HOOC- (CH 2) n-COOH} ····· (1)
(In Formula (1), n is an integer of 1-20.)

［式中、Ｒ¹〜Ｒ⁵は、それぞれ独立して、１価の有機基であり、Ｒ¹〜Ｒ⁵の少なくとも一つは水酸基である。］

［式中、Ｒ⁶〜Ｒ²⁰は、それぞれ独立して、１価の有機基であり、Ｒ⁶〜Ｒ²⁰の少なくとも一つは水酸基またはカルボキシル基である。］ (5) The conductive connection sheet according to (2) or (3), wherein the compound having the flux function contains at least one of the compounds represented by the following general formula (2) and the following general formula (3). .

[Wherein, R ^{1 to} R ⁵ are each independently a monovalent organic group, and at least one of R ^{1 to} R ⁵ is a hydroxyl group. ]

[Wherein, R ^{6 to} R ²⁰ are each independently a monovalent organic group, and at least one of R ^{6 to} R ²⁰ is a hydroxyl group or a carboxyl group. ]

  (6) In the said resin composition, content of the compound which has the said flux function is a conductive connection sheet in any one of said (2) thru | or (5) which is 1 to 50 weight%.

  (7) The metal layer includes tin (Sn), lead (Pb), silver (Ag), bismuth (Bi), indium (In), zinc (Zn), nickel (Ni), antimony (Sb), iron ( (1) to (6) which is an alloy of at least two kinds of metals selected from the group consisting of Fe), aluminum (Al), gold (Au), germanium (Ge) and copper (Cu), or a simple substance of tin. The conductive connection sheet according to any one of the above.

  (8) The conductive connection sheet according to (7), wherein the metal layer includes a Sn—Pb alloy, a Sn—Ag—Cu alloy, or a Sn—Ag alloy as a main material.

  (9) The conductive connection sheet according to (8), wherein the metal layer includes a Sn-37Pb alloy or a Sn-3.0Ag-0.5Cu alloy as a main material.

  (10) Furthermore, the said resin composition layer is a conductive connection sheet in any one of said (1) thru | or (9) containing an inorganic filler.

  (11) The conductive connection sheet according to any one of (1) to (10), wherein the resin composition layer and the metal layer are bonded to each other.

  (12) The laminate is composed of two resin composition layers and one metal layer, and the resin composition layer, the metal layer, and the resin composition layer are laminated in this order. The conductive connection sheet according to any one of (1) to (11).

  (13) An arrangement step of arranging the conductive connection sheet according to any one of (1) to (12) between opposing terminals, a melting point of the metal material or more, and curing of the resin composition A method for connecting terminals, comprising: a heating step of heating the conductive connection sheet at a temperature not completed; and a curing step of curing the resin composition.

  (14) The disposing step of disposing the conductive connection sheet according to any one of (1) to (12) above the electrode of the electronic member, and the curing of the resin composition that is equal to or higher than the melting point of the metal material. And a heating step of heating the conductive connection sheet at a temperature at which the connection is not completed.

  (15) A semiconductor in which terminals facing each other are electrically connected via a connection portion formed using the conductive connection sheet according to any one of (1) to (12). apparatus.

  (16) Electrons characterized in that opposing terminals are electrically connected via a connection portion formed using the conductive connection sheet according to any one of (1) to (12). machine.

  With the configuration of the conductive connection sheet of the present invention, it is possible to suppress the formation of an excessive oxide film on the surface of the metal layer, so that the heat melted metal material is selectively aggregated between the terminals to form the connection portion. When forming, the cohesive force of the metal material between terminals can be improved.

  Furthermore, using such a conductive connection sheet, when applied to the formation of a connection portion that electrically connects the terminals, the heat-melted metal material is selectively aggregated between the terminals to form a connection portion, When forming a sealing layer composed of a curable resin component around it, it is possible to accurately suppress or prevent the generation of voids in the sealing layer.

  From these things, since the insulation between adjacent terminals is ensured by a sealing layer, it can prevent reliably that a leak current arises between adjacent terminals.

  Furthermore, when the conductive connection sheet is used to form connection terminals provided correspondingly on the electrodes, the formation of an excessive oxide film on the surface of the metal layer is suppressed, and in the reinforcing layer Since generation of voids is accurately suppressed or prevented, insulation between adjacent connection terminals is ensured by the reinforcing layer, so that leakage current can be reliably prevented between adjacent connection terminals. it can.

  Further, when a compound having a flux function is included in the resin composition layer, hydrogen ions included in the compound having a flux function react with moisture due to the moisture contained in the resin composition layer. Inactivation can be suppressed or prevented accurately.

  Further, even when the semiconductor device or the electronic device is subjected to the HAST test, it is possible to prevent a leakage current from being generated and the insulation reliability of the semiconductor device or the electronic device from being lowered.

It is a longitudinal section showing an example of a semiconductor device manufactured using the conductive connection sheet of the present invention. It is a longitudinal section showing an embodiment of a conductive connection sheet of the present invention. It is a top view which shows the other structural example of the metal layer with which the conductive connection sheet of this invention is provided. It is a longitudinal cross-sectional view for demonstrating the method to manufacture the connection part and sealing layer with which a semiconductor device is provided using the connection method between the terminals of this invention. It is a longitudinal cross-sectional view for demonstrating the method to measure the wetting spread rate of a metal ball based on JISZ3197. It is a longitudinal cross-sectional view for demonstrating the method of forming a connection terminal corresponding to the terminal with which a semiconductor chip is provided using the formation method of the connection terminal of this invention.

  Hereinafter, a conductive connection sheet, a connection method between terminals, a connection terminal formation method, a semiconductor device, and an electronic apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  First, prior to describing the conductive connection sheet of the present invention, a semiconductor device manufactured using the conductive connection sheet of the present invention will be described.

<Semiconductor device>
FIG. 1 is a longitudinal sectional view showing an example of a semiconductor device manufactured using the conductive connection sheet of the present invention. In the following description, the upper side in FIG. 1 is referred to as “upper” 8 and the lower side is referred to as “lower”.

  A semiconductor device 10 shown in FIG. 1 includes a semiconductor chip (semiconductor element) 20, an interposer (substrate) 30 that supports the semiconductor chip 20, and a plurality of conductive bumps (terminals) 70.

  The interposer 30 is an insulating substrate and is made of various resin materials such as polyimide, epoxy, cyanate, bismaleimide triazine (BT resin). The plan view shape of the interposer 30 is usually a square such as a square or a rectangle.

  On the upper surface (one surface) of the interposer 30, for example, a terminal 41 made of a conductive metal material such as copper is provided in a predetermined shape.

  The interposer 30 is formed with a plurality of vias (through holes: through holes) (not shown) penetrating in the thickness direction.

  Each bump 70 has one end (upper end) electrically connected to a part of the terminal 41 via each via, and the other end (lower end) protruding from the lower surface (the other surface) of the interposer 30. Yes.

  A portion of the bump 70 protruding from the interposer 30 has a substantially spherical shape (Ball shape).

  The bumps 70 are mainly composed of a brazing material such as solder, silver brazing, copper brazing, or phosphor copper brazing.

  A terminal 41 is formed on the interposer 30. A terminal 21 included in the semiconductor chip 20 is electrically connected to the terminal 41 via a connection portion 81.

  Further, a gap between the semiconductor chip 20 and the interposer 30 is filled with a sealing material made of various resin materials, and a sealing layer 80 is formed by a cured product of this sealing material. . The sealing layer 80 has a function of improving the bonding strength between the semiconductor chip 20 and the interposer 30 and a function of preventing entry of foreign matter, moisture, and the like into the gap.

  In the semiconductor device 10 having such a configuration, the conductive connection sheet of the present invention is applied to the formation of the connection portion 81 and the sealing layer 80.

Hereinafter, the conductive connection sheet of the present invention will be described.
<Conductive connection sheet>
FIG. 2 is a longitudinal sectional view showing an embodiment of the conductive connection sheet of the present invention, and FIG. 3 is a plan view showing another configuration example of the metal layer provided in the conductive connection sheet of the present invention. In the following description, the upper side in FIG. 2 is referred to as “upper” and the lower side is referred to as “lower”.

  The conductive connection sheet of the present invention is composed of a laminate including a resin composition layer containing a curable resin component and a metal layer composed of a low-melting-point metal material, and the resin composition layer The water absorption before curing is more than 0.0% and 1.2% or less, and the water absorption after curing is more than 0.0% and 2.5% or less.

  When such a conductive connection sheet is used, formation of an excessive oxide film on the surface of the metal layer can be suppressed. Therefore, the metal material heated and melted is selectively aggregated between the terminals to form a connection portion. In this case, the cohesive force of the metal material between the terminals can be improved.

  Furthermore, using such a conductive connection sheet, when applied to the formation of a connection portion that electrically connects the terminals, the heat-melted metal material is selectively aggregated between the terminals to form a connection portion, When forming a sealing layer composed of a curable resin component around it, it is possible to accurately suppress or prevent the generation of voids in the sealing layer.

  From these things, since the insulation between adjacent terminals is ensured by a sealing layer, it can prevent reliably that a leak current arises between adjacent terminals.

  Furthermore, when the conductive connection sheet is used to form connection terminals provided correspondingly on the electrodes, the formation of an excessive oxide film on the surface of the metal layer is suppressed, and in the reinforcing layer Since generation of voids is accurately suppressed or prevented, insulation between adjacent connection terminals is ensured by the reinforcing layer, so that leakage current can be reliably prevented between adjacent connection terminals. it can.

  Further, when a compound having a flux function is included in the resin composition layer, hydrogen ions included in the compound having a flux function react with moisture due to the moisture contained in the resin composition layer. , It is possible to accurately suppress or prevent the inactivation of such a compound.

  Further, even when a HAST test is performed on a semiconductor device or an electronic device having a connection portion formed using a conductive connection sheet, a leakage current is generated, thereby preventing a reduction in insulation reliability of the semiconductor device or the electronic device. be able to.

  In the present embodiment, as shown in FIG. 2, in the conductive connection sheet 1, the first resin composition layer 11, the metal layer 12, and the second resin composition layer 13 are joined together in this order. Thus, it is constituted by a laminated body having a three-layer structure laminated.

  In the conductive connection sheet 1 having such a configuration, the first resin composition layer 11 and the second resin composition layer 13 are composed of a resin composition containing a curable resin component, and the metal layer 12 has a low melting point. It is a layer comprised with the metal foil comprised with a metal material.

  Hereinafter, although each layer which comprises the conductive connection sheet 1 is demonstrated one by one, about the 1st resin composition layer 11 and the 2nd resin composition layer 13, it is comprised with the resin composition containing both curable resin components. Therefore, the first resin composition layer 11 will be described as a representative. Hereinafter, the first resin composition layer 11 and the second resin composition layer 13 may be simply referred to as “resin composition layer 11” and “resin composition layer 13”.

<< Resin composition layer 11 >>
In the present embodiment, the resin composition layer 11 is composed of a resin composition (curable resin composition) containing a curable resin component.

  In the present invention, the resin composition can be used in a liquid or solid form at room temperature. In the present specification, “liquid state at room temperature” means a state that does not have a certain form at room temperature (25 ° C.), and includes a paste form.

  Examples of the resin composition (curable resin composition) include a curable resin composition that is cured by heating, a curable resin composition that is cured by irradiation with actinic radiation, and the like. A curable resin composition that cures is preferably used. The curable resin composition cured by heating is excellent in mechanical properties such as linear expansion coefficient and elastic modulus after curing.

  Below, as a curable resin composition, what contains a curable resin component and fuse | melts and hardens | cures by heating is demonstrated to an example.

  In addition to the curable resin component, the curable resin composition contains a compound having a flux function, a film-forming resin, a curing agent, a curing accelerator, a silane coupling agent, and the like as necessary. May be.

Hereinafter, various materials contained in the curable resin composition will be described in detail.
(I) Curable resin component Although a curable resin component will not be specifically limited if it melts and hardens | cures by heating, Usually, what can be used as an adhesive agent component for semiconductor device manufacture is used.

  Such a curable resin component is not particularly limited. For example, epoxy resin, phenoxy resin, silicone resin, oxetane resin, phenol resin, (meth) acrylate resin, polyester resin (unsaturated polyester resin), diallyl phthalate resin , Maleimide resin, polyimide resin (polyimide precursor resin), bismaleimide-triazine resin and the like. In particular, the use of a thermosetting resin containing at least one selected from the group consisting of epoxy resins, (meth) acrylate resins, phenoxy resins, polyester resins, polyimide resins, silicone resins, maleimide resins, and bismaleimide-triazine resins. preferable. Among these, an epoxy resin is preferable from the viewpoint of excellent curability and storage stability, heat resistance, moisture resistance, and chemical resistance of a cured product. In addition, these curable resin components may be used individually by 1 type, or may use 2 or more types together.

  The epoxy resin is not particularly limited, and any epoxy resin that is liquid at room temperature and solid at room temperature can be used. It is also possible to use an epoxy resin that is liquid at room temperature and an epoxy resin that is solid at room temperature. When the curable resin composition is liquid, it is preferable to use an epoxy resin that is liquid at room temperature. When the curable resin composition is solid, both liquid and solid epoxy resins should be used. Furthermore, it is preferable that the curable resin composition contains a film-forming resin component.

  Although it does not specifically limit as a liquid epoxy resin at room temperature (25 degreeC), A bisphenol A type epoxy resin, a bisphenol F type epoxy resin, etc. are mentioned, Among these, it can use combining 1 type or 2 types. .

  The epoxy equivalent of the epoxy resin that is liquid at room temperature is preferably 150 to 300 g / eq, more preferably 160 to 250 g / eq, and particularly preferably 170 to 220 g / eq. When the epoxy equivalent is less than the lower limit, depending on the type of epoxy resin used, the shrinkage of the cured product tends to increase, and the semiconductor device 10 and the electronic device including the semiconductor device 10 may be warped. Moreover, when it exceeds the said upper limit, when it is set as the structure which uses a film-forming resin component together with a curable resin composition, it may show the tendency for the reactivity with a film-forming resin component, especially a polyimide resin to fall. .

  Further, the epoxy resin solid at room temperature (25 ° C.) is not particularly limited, but bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, glycidylamine type epoxy resin. , A glycidyl ester type epoxy resin, a trifunctional epoxy resin, a tetrafunctional epoxy resin, and the like. Among these, one kind or two or more kinds can be used in combination. Among these, solid trifunctional epoxy resins, cresol novolac type epoxy resins, and the like are preferably used.

  In addition, 150-3000 g / eq is preferable, as for the epoxy equivalent of a solid epoxy resin at room temperature, 160-2500 g / eq is more preferable, and 170-2000 g / eq is especially preferable.

  The softening point of the epoxy resin that is solid at room temperature is preferably about 40 to 120 ° C, more preferably about 50 to 110 ° C, and particularly preferably about 60 to 100 ° C. When the softening point is within the above range, tackiness of the curable resin composition can be suppressed, and the softening point can be easily handled.

  Moreover, in the curable resin composition, the blending amount of the curable resin component described above can be appropriately set according to the form of the curable resin composition to be used.

  For example, in the case of a liquid curable resin composition, the blending amount of the curable resin component is preferably 10% by weight or more, more preferably 15% by weight or more in the curable resin composition. It is preferably 20% by weight or more, more preferably 25% by weight or more, still more preferably 30% by weight or more, and particularly preferably 35% by weight or more. Further, it is preferably less than 100% by weight, more preferably 95% by weight or less, further preferably 90% by weight or less, still more preferably 75% by weight or less, and 65% by weight or less. Is still more preferable, and it is especially preferable that it is 55 weight% or less.

  In the case of a solid curable resin composition, the amount of the curable resin component in the curable resin composition is preferably 5% by weight or more, and preferably 10% by weight or more. More preferably, it is more preferably 15% by weight or more, and particularly preferably 20% by weight or more. Further, it is preferably 90% by weight or less, more preferably 85% by weight or less, still more preferably 80% by weight or less, still more preferably 75% by weight or less, and 65% by weight or less. It is still more preferable that it is 55% by weight or less.

  When the blending amount of the curable resin component in the curable resin composition is within the above range, the electrical connection strength and the mechanical adhesive strength between the terminals 21 and 41 can be sufficiently secured.

(Ii) Film-forming resin component As described above, when a solid resin is used as the curable resin composition, in addition to the curable resin component, the film-forming resin is further included in the curable resin composition. A constitution containing a resin component is preferred.

  Such a film-forming resin component is not particularly limited as long as it is soluble in an organic solvent and has a film-forming property (film-forming property) alone, and is not limited to a thermoplastic resin or a thermosetting resin. Any of the resins can be used, or a combination of these can be used.

  Specifically, the film-forming resin component is not particularly limited. For example, (meth) acrylic resin, phenoxy resin, polyester resin, polyurethane resin, polyimide resin, polyamideimide resin, siloxane-modified polyimide resin, polybutadiene resin , Polypropylene resin, styrene-butadiene-styrene copolymer, styrene-ethylene-butylene-styrene copolymer, polyacetal resin, polyvinyl butyral resin, polyvinyl acetal resin, butyl rubber, chloroprene rubber, polyamide resin, acrylonitrile-butadiene copolymer, Examples include acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer, polyvinyl acetate, nylon, and the like. In combination it can be used. Among these, (meth) acrylic resins, phenoxy resins, polyester resins, polyamide resins and polyimide resins are preferable.

  In this specification, “(meth) acrylic resin” refers to a polymer of (meth) acrylic acid and its derivatives, or a co-polymerization of (meth) acrylic acid and its derivatives and other monomers. Means coalescence. Here, the expression “(meth) acrylic acid” or the like means “acrylic acid or methacrylic acid” or the like.

  The (meth) acrylic resin is not particularly limited. For example, polyacrylic acid such as polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, and polyacrylic acid-2-ethylhexyl. Acid ester, polymethyl methacrylate, polyethyl methacrylate, polymethacrylate such as polybutyl methacrylate, polyacrylonitrile, polymethacrylonitrile, polyacrylamide, butyl acrylate-ethyl acrylate-acrylonitrile copolymer, acrylonitrile- Butadiene copolymer, acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, methyl methacrylate-styrene copolymer, methacryl Methyl-acrylonitrile copolymer, methyl methacrylate-α-methylstyrene copolymer, butyl acrylate-ethyl acrylate-acrylonitrile-2-hydroxyethyl methacrylate-methacrylic acid copolymer, butyl acrylate-ethyl acrylate-acrylonitrile 2-hydroxyethyl methacrylate-acrylic acid copolymer, butyl acrylate-acrylonitrile-2-hydroxyethyl methacrylate copolymer, butyl acrylate-acrylonitrile-acrylic acid copolymer, butyl acrylate-ethyl acrylate-acrylonitrile copolymer Examples thereof include a polymer and an ethyl acrylate-acrylonitrile-N, N-dimethylacrylamide copolymer, and one or more of these can be used in combination. Of these, butyl acrylate-ethyl acrylate-acrylonitrile copolymer and ethyl acrylate-acrylonitrile-N, N-dimethylacrylamide are preferable.

  Further, the skeleton of the phenoxy resin is not particularly limited, and examples thereof include bisphenol A type, bisphenol F type, and biphenyl type.

  The polyimide resin is not particularly limited as long as it has an imide bond in the repeating unit. For example, the polyimide resin is obtained by reacting diamine and acid dianhydride and heating and dehydrating and ring-closing the resulting polyamic acid. Can be mentioned.

  Examples of the diamine include, but are not limited to, aromatics such as 3,3′-dimethyl-4,4′diaminodiphenyl, 4,6-dimethyl-m-phenylenediamine, and 2,5-dimethyl-p-phenylenediamine. Examples include diamines and siloxane diamines such as 1,3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane, and one or more of these can be used in combination. .

  Examples of the acid dianhydride include 3,3,4,4′-biphenyltetracarboxylic acid, pyromellitic dianhydride, 4,4′-oxydiphthalic dianhydride, and the like. One kind or a combination of two or more kinds can be used.

  The polyimide resin may be either soluble or insoluble in the solvent, but it is easy to varnish when mixed with other components (curable resin component), and is a solvent because it is easy to handle. Soluble ones are preferred. In particular, a siloxane-modified polyimide resin is preferably used because it can be dissolved in various organic solvents.

  The weight average molecular weight of the film-forming resin is not particularly limited, but is preferably about 8,000 to 1,000,000, more preferably about 8,500 to 950,000, and 9,000 to More preferably, it is about 900,000. When the weight average molecular weight of the film-forming resin is within the above range, the film-forming property can be improved, and the fluidity of the resin composition layer 11 before curing can be suppressed.

  In addition, the weight average molecular weight of film-forming resin can be measured by GPC (gel permeation chromatography), for example.

  As the film-forming resin component, commercially available products can be used, and various additives such as plasticizers, stabilizers, antistatic agents and pigments can be used as long as the effects of the present invention are not impaired. What was blended can also be used.

  Moreover, in the curable resin composition, the blending amount of the film-forming resin component described above can be appropriately set according to the form of the curable resin composition to be used.

  For example, in the case of a solid curable resin composition, the blending amount of the film-forming resin component is preferably 5% by weight or more and preferably 10% by weight or more in the curable resin composition. Is more preferable, and it is further more preferable that it is 15 weight% or more. Further, it is preferably 50% by weight or less, more preferably 45% by weight or less, and further preferably 40% by weight or less. When the blending amount of the film-forming resin component is within the above range, the fluidity of the curable resin composition before melting can be suppressed, and the resin composition layer (conductive connection material) 11 can be easily handled. It becomes.

(Iii) Compound having flux function As described above, it is preferable that the curable resin composition further includes a flux function in addition to the curable resin component. The compound having a flux function has an action of reducing the surface oxide films formed on the terminals 21 and 41 and the metal layer 12. Therefore, if such a compound is contained in the curable resin composition, the surfaces of the terminals 21 and 41 and the metal layer 12 will be described in detail as will be described later in connection method and sealing layer formation method. Even if an oxide film is formed, the oxide film can be reliably removed by the action of this compound. As a result, the molten metal layer 12 aggregates between the terminals 21 and 41 with higher selectivity.

  Although it does not specifically limit as a compound which has such a flux function, For example, the compound which has a phenolic hydroxyl group and / or a carboxyl group is used preferably.

  Examples of the compound having a phenolic hydroxyl group include phenol, o-cresol, 2,6-xylenol, p-cresol, m-cresol, o-ethylphenol, 2,4-xylenol, 2,5-xylenol, m- Ethylphenol, 2,3-xylenol, meditol, 3,5-xylenol, p-tert-butylphenol, catechol, p-tert-amylphenol, resorcinol, p-octylphenol, p-phenylphenol, bisphenol F, bisphenol AF, biphenol Monomers containing phenolic hydroxyl groups such as diallyl bisphenol F, diallyl bisphenol A, trisphenol, tetrakisphenol, phenol novolac resins, o-cresol novolac resins, bisphenols Lumpur F novolak resins, resins containing phenolic manufactured hydroxyl group, such as bisphenol A novolac resins. Can be used singly or in combination of two or more of them.

  Examples of the compound having a carboxyl group include aliphatic acid anhydrides, alicyclic acid anhydrides, aromatic acid anhydrides, aliphatic carboxylic acids, and aromatic carboxylic acids. Examples of the aliphatic acid anhydride include succinic anhydride, polyadipic acid anhydride, polyazeline acid anhydride, polysebacic acid anhydride, and the like. Examples of the alicyclic acid anhydride include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid. An anhydride etc. are mentioned. Examples of the aromatic acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, ethylene glycol bistrimellitate, glycerol trislimitate, etc. Species or a combination of two or more can be used.

The aliphatic carboxylic acid is not particularly limited, for example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, acrylic acid, Methacrylic acid, crotonic acid, oleic acid, fumaric acid, maleic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, pimelic acid, etc. Two or more kinds can be used in combination. Among these, the following formula (1):
_{HOOC- (CH 2) n -COOH (} 1)
(In Formula (1), n is an integer of 1-20.)
Of these, adipic acid, sebacic acid, and dodecanedioic acid are more preferably used.

  The structure of the aromatic carboxylic acid is not particularly limited, but a compound represented by the following formula (2) or the following formula (3) is preferable.

［式中、Ｒ¹〜Ｒ⁵は、それぞれ独立して、１価の有機基であり、Ｒ¹〜Ｒ⁵の少なくとも一つは水酸基である。］

[Wherein, R ^{1 to} R ⁵ are each independently a monovalent organic group, and at least one of R ^{1 to} R ⁵ is a hydroxyl group. ]

［式中、Ｒ⁶〜Ｒ²⁰は、それぞれ独立して、１価の有機基であり、Ｒ⁶〜Ｒ²⁰の少なくとも一つは水酸基またはカルボキシル基である。］

[Wherein, R ^{6 to} R ²⁰ are each independently a monovalent organic group, and at least one of R ^{6 to} R ²⁰ is a hydroxyl group or a carboxyl group. ]

  Examples of such aromatic carboxylic acids include benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, merophanic acid, platonic acid, pyromellitic acid, meritic acid, and xylic acid. , Hemelic acid, mesitylene acid, prenylic acid, toluic acid, cinnamic acid, salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6 -Dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid), 4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid, 3 , Naphthoic acid derivatives such as 5--2-dihydroxy-2-naphthoic acid, phenolphthaline, diphenolic acid, etc. The recited may be used singly or in combination of two or more of them.

  The compound having such a flux function exhibits an action of reducing the surface oxide film of the metal layer 12 and the terminals 21 and 41 and is cured so that the metal layer 12 and the terminals 21 and 41 can be electrically connected. It preferably has a function as a curing agent for curing the curable resin component, that is, a functional group capable of reacting with the curable resin component.

  Such a functional group is appropriately selected according to the type of the curable resin component. For example, when the curable resin component is an epoxy resin, a functional group capable of reacting with an epoxy group such as a carboxyl group, a hydroxyl group, and an amino group. Is mentioned. The compound having such a flux function reduces the surface oxide film formed on the metal layer 12 and the terminals 21 and 41 when the curable resin composition is melted to improve the wettability of these surfaces, and the connection portion 81 is formed. It can be easily formed and the terminals 21 and 41 can be electrically connected. Furthermore, after the electrical connection between the terminals 21 and 41 is completed by the connecting portion 81, this compound acts as a curing agent and is added to the curable resin component to increase the elastic modulus or Tg of the resin. Demonstrate. Therefore, when a compound having such a flux function is used as the flux, flux cleaning is unnecessary, and the occurrence of ion migration due to the remaining flux can be suppressed or prevented accurately.

  Examples of the compound having such a function and having a flux function include compounds having at least one carboxyl group. For example, when the curable resin component is an epoxy resin, examples thereof include aliphatic dicarboxylic acids and compounds having a carboxyl group and a phenolic hydroxyl group.

  Although it does not specifically limit as said aliphatic dicarboxylic acid, The compound which two carboxyl groups couple | bonded with the aliphatic hydrocarbon group is mentioned. The aliphatic hydrocarbon group may be saturated or unsaturated acyclic, or may be saturated or unsaturated cyclic. Further, when the aliphatic hydrocarbon group is acyclic, it may be linear or branched.

  Examples of such aliphatic dicarboxylic acids include compounds in which n is an integer of 1 to 20 in the formula (1). When n in the formula (1) is within the above range, the balance between the flux activity, the outgas at the time of adhesion, the elastic modulus after curing of the curable resin composition, and the glass transition temperature becomes good. In particular, n is preferably 3 or more from the viewpoint that the increase in the elastic modulus after curing of the curable resin composition can be suppressed and the adhesion with an adherend such as the interposer 30 can be improved. From the viewpoint of suppressing the decrease in elastic modulus and further improving the connection reliability, n is preferably 10 or less.

  Examples of the aliphatic dicarboxylic acid represented by the formula (1) include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, and tetradecanedioic acid. Pentadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid and the like. Among these, adipic acid, suberic acid, sebacic acid and dodencandioic acid are preferable, and sebacic acid is more preferable.

  Further, examples of the compound having a carboxyl group and a phenolic hydroxyl group include salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), and 2,6-dihydroxy. Benzoic acid derivatives such as benzoic acid, 3,4-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid), 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2 -Naphthoic acid derivatives such as naphthoic acid, phenolphthaline, diphenolic acid and the like. Of these, phenolphthaline, gentisic acid, 2,4-dihydroxybenzoic acid, and 2,6-dihydroxybenzoic acid are preferable, and phenolphthaline and gentisic acid are more preferable.

  The compounds having the flux function as described above may be used alone or in combination of two or more.

  In addition, since any compound easily absorbs moisture and causes voids, in the present invention, it is preferably dried in advance before use.

  Content of the compound which has a flux function can be suitably set according to the form of the resin composition to be used.

  For example, when the resin composition is liquid, the content of the compound having a flux function is preferably 1% by weight or more, more preferably 2% by weight or more, and more preferably 3% by weight with respect to the total weight of the curable resin composition. The above is particularly preferable. Moreover, 50 weight% or less is preferable, 40 weight% or less is more preferable, 30 weight% or less is further more preferable, and 25 weight% or less is especially preferable.

  In the case of a solid resin composition, the content of the compound having a flux function is preferably 1% by weight or more, more preferably 2% by weight or more based on the total weight of the curable resin composition, 3% by weight or more is particularly preferable. Moreover, 50 weight% or less is preferable, 40 weight% or less is more preferable, 30 weight% or less is further more preferable, and 25 weight% or less is especially preferable.

  When the content of the compound having the flux function is within the above range, the metal layer 12 and the surface oxide films of the terminals 21 and 41 can be reliably removed so that they can be electrically joined. Furthermore, when the resin composition is a curable resin composition, it can be efficiently added to the curable resin component at the time of curing to increase the elastic modulus or Tg of the curable resin composition. Moreover, generation | occurrence | production of the ion migration resulting from the compound which has an unreacted flux function can be suppressed.

(Iv) Curing Agent The curing agent other than the compound having a flux function is not particularly limited, and examples thereof include phenols, amines, and thiols. Such a hardening | curing agent can be suitably selected according to the kind etc. of curable resin component. For example, when an epoxy resin is used as the curable resin component, good reactivity with the epoxy resin, low dimensional change during curing, and appropriate physical properties after curing (eg heat resistance, moisture resistance, etc.) are obtained. In view of the above, it is preferable to use a phenol as a curing agent, and a bifunctional or higher functional phenol is more preferably used in terms of excellent physical properties after curing of the curable resin component. In addition, such a hardening | curing agent may be used individually by 1 type, and may be used in combination of 2 or more type.

  Examples of phenols include bisphenol A, tetramethylbisphenol A, diallyl bisphenol A, biphenol, bisphenol F, diallyl bisphenol F, trisphenol, tetrakisphenol, phenol novolac resin, cresol novolac resin, etc. Species or a combination of two or more can be used. Among these, a phenol novolac resin and a cresol novolac resin are preferable from the viewpoints of good melt viscosity, reactivity with an epoxy resin, and excellent physical properties after curing.

  In addition, in the curable resin composition, the amount of the curing agent described above is such that the type of the curable resin component and the curing agent to be used, and the compound having a flux function have a functional group that functions as a curing agent. It is set as appropriate depending on the type of group and the amount used.

  For example, when an epoxy resin is used as the curable resin, the content of the curing agent is preferably about 0.1 to 50% by weight with respect to the total weight of the curable resin composition, 0.2 to 40 It is more preferably about wt%, and further preferably about 0.5 to 30 wt%. When the content of the curing agent is within the above range, the electrical connection strength and the mechanical adhesive strength of the connection portion 81 formed between the terminals 21 and 41 can be sufficiently ensured.

(V) Curing accelerator As described above, a curing accelerator can be further added to the curable resin composition. Thereby, a curable resin composition can be hardened reliably and easily.

  Although it does not specifically limit as a hardening accelerator, For example, imidazole, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2- Phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methyl Imidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2, 4 Diamino-6- [2′-methylimidazolyl (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-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 -Isocyanuric acid adduct of s-triazine, isocyanuric acid adduct of 2-phenylimidazole, isocyanuric acid adduct of 2-methylimidazole, 2-phenyl-4,5-dihydroxydimethylimidazole, 2-phenyl-4-methyl- Examples include imidazole compounds such as 5-hydroxymethylimidazole, and one or more of these may be used in combination. Kill.

  Moreover, in the curable resin composition, the blending amount of the above-described curing accelerator can be appropriately set according to the type of the curing accelerator to be used.

  For example, when an imidazole compound is used, the amount of the imidazole compound is preferably 0.001% by weight or more, more preferably 0.003% by weight or more in the curable resin composition, More preferably, it is 0.005% by weight or more. Further, it is preferably 1.0% by weight or less, more preferably 0.7% by weight or less, and further preferably 0.5% by weight or less. When the blending amount of the imidazole compound is less than the lower limit, depending on the type of the curing accelerator to be used, the effect as the curing accelerator may not be sufficiently exhibited, and the curable resin composition may not be sufficiently cured. . Moreover, when the compounding quantity of an imidazole compound exceeds the said upper limit, before the hardening of a curable resin composition is completed, the metal layer 12 of a molten state cannot fully move to the surface of the terminals 21 and 41, but it is in an insulating area | region. There is a possibility that a part of the metal layer 12 remains in the sealing layer 80 to be formed, and the insulation in the sealing layer 80 cannot be sufficiently secured.

(Vi) Silane Coupling Agent As described above, a silane coupling agent can be further added to the curable resin composition.

  Although it does not specifically limit as a silane coupling agent, For example, an epoxy silane coupling agent, an aromatic containing aminosilane coupling agent, etc. are mentioned. By adding such a silane coupling agent, it is possible to improve the adhesion between the joining member (adhered body) such as the interposer 30 and the curable resin composition.

  In addition, such a silane coupling agent may be used individually by 1 type, and can also be used in combination of 2 or more type.

  Moreover, in the curable resin composition, the blending amount of the silane coupling agent described above is appropriately set according to the types of the joining member, the curable resin component, and the like. For example, in the curable resin composition, it is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, and further preferably 0.1% by weight or more. Further, it is preferably 2% by weight or less, more preferably 1.5% by weight or less, and further preferably 1% by weight or less.

  In addition to the above-described components, the curable resin composition may further contain a plasticizer, a stabilizer, a tackifier, a lubricant, an antioxidant, an antistatic agent, a pigment, and the like.

  Moreover, the curable resin composition as described above can be prepared by mixing and dispersing the above components. The mixing method and dispersion method of each component are not specifically limited, It can mix and disperse | distribute by a conventionally well-known method.

  Moreover, you may prepare the liquid curable resin composition by mixing each said component in a solvent or under absence of solvent. The solvent used at this time is not particularly limited as long as it is inert to each component. For example, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone (DIBK), cyclohexanone, Ketones such as diacetone alcohol (DAA), aromatic hydrocarbons such as benzene, xylene and toluene, alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol and n-butyl alcohol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, Cellosolves such as methyl cellosolve acetate and ethyl cellosolve acetate, N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), dimethylformamide (DMF), dibasic acid ester (DBE), 3 Ethyl ethoxypropionate (EEP), dimethyl carbonate (DMC) and the like, can be used singly or in combination of two or more of them. Moreover, it is preferable that the usage-amount of a solvent is an quantity from which the solid content concentration of the component mixed with the solvent will be 10 to 60 weight%.

  In the present invention, the curable resin composition described above is 10 to 90% by weight of epoxy resin, 0.1 to 50% by weight of curing agent, and 5 to 50 of film-forming resin with respect to the total weight of the resin composition. Those containing 1 to 50% by weight of a compound having a weight% and a flux function are more preferred. The epoxy resin is 20 to 80% by weight, the curing agent is 0.2 to 40% by weight, the film-forming resin is 10 to 45% by weight, and the compound having a flux function is 2 to 40% by weight with respect to the total weight of the resin composition. More preferably, those containing The epoxy resin is 35 to 55% by weight, the curing agent is 0.5 to 30% by weight, the film-forming resin is 15 to 40% by weight, and the compound having a flux function is 3 to 25% by weight with respect to the total weight of the resin composition. Those containing are particularly preferred. As a result, it is possible to sufficiently ensure the electrical connection strength and the mechanical adhesive strength between the terminals 21 and 41.

  Moreover, the thickness of the resin composition layer 11 in the conductive connection sheet 1 is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, and further preferably 5 μm or more. The thickness of the resin composition layer 11 is preferably 200 μm or less, more preferably 150 μm or less, and further preferably 100 μm or less. When the thickness of the resin composition layer 11 is within the above range, the gap between the adjacent terminals 21 and 41 can be sufficiently filled with the resin composition to form the sealing layer 80, and the resin composition can be cured. Thereafter, the mechanical adhesive strength after solidification and the electrical connection between the opposing terminals 21 and 41 can be sufficiently ensured, and the connection portion 81 can be formed.

  In addition, in this embodiment, although the conductive connection sheet 1 is a structure provided with two layers, the 1st resin composition layer 11 and the 2nd resin composition layer 13, the 2nd resin composition layer 13 is What is necessary is just the thing of the structure similar to the 1st resin composition layer 11 mentioned above, the thing of the same composition as the 1st resin composition layer 11 may be sufficient, and the thing of a different composition may be sufficient. .

  Moreover, the conductive connection sheet 1 should just be provided with the at least 1 layer of resin composition layer, and even if any one of the 1st resin composition layer 11 and the 2nd resin composition layer 13 is abbreviate | omitted. Moreover, the thing of the structure provided with the 3rd and 4th resin composition layer different from the 1st resin composition layer 11 and the 2nd resin composition layer 13 may be sufficient.

  In the resin composition layer 11 having such a configuration, in the present invention, the water absorption before curing of the resin composition layer is more than 0.0% and 1.2% or less, and the water absorption after curing is 0.0. More than% and 2.5% or less.

  First, when the water absorption rate before curing in the resin composition layer 11 included in the conductive connection sheet 1 is within such a range, formation of an excessive oxide film on the surface of the metal layer 12 can be suppressed. Thereby, in the heating step in the connection method between terminals and the formation method of the connection terminals described later, the oxide film can be easily removed by the reducing action provided by the compound having a flux function, so that the heated and melted metal material Can be selectively aggregated between the terminals 21 and 41 with a high cohesive force. As a result, the connection portion 81 or the connection terminal 85 can be reliably formed without leaving the metal material in the sealing layer 80 or the reinforcing layer 86.

  Furthermore, in the heating step, when the sealing layer 80 or the reinforcing layer 86 is formed in a region where the terminals 21, 41 or the connection terminals 85 are not formed, a large amount of moisture exists in the resin composition layer 11. It is possible to accurately suppress or prevent the generation of voids in these layers due to the above.

  From these things, since the insulation between the adjacent terminals 21 and 41 or the connection terminal 85 is ensured reliably by the sealing layer 80 or the reinforcement layer 86, between the adjacent terminals 21 and 41 or between the connection terminals 85. Thus, leakage current can be reliably prevented.

  Also, if the resin composition layer contains a large amount of water, the hydrogen ions of the compound having the flux function react with the water and the compound is deactivated. By setting within such a range, the deactivation of the compound having a flux function can be accurately suppressed or prevented. Therefore, from this point of view, the oxide film formed on the surface of the metal layer 12 can be easily removed in the heating step, so that the heat-melted metal material is selectively interposed between the terminals 21 and 41. It can be agglomerated with high agglomeration force.

  Furthermore, if a large amount of moisture is contained in the cured resin composition 11 layer, a leakage current is generated between the adjacent terminals 21 and 41 or the connection terminals 85 during the HAST test, resulting in poor insulation. However, by setting the water absorption after curing within the range as described above, it is possible to reliably prevent the occurrence of leakage current.

Here, the water absorption ratio WA1 (%) before curing of the resin composition layer 11 is referred to as a resin composition layer 11 provided in the conductive connection sheet 1 manufactured by the method for manufacturing a conductive connection sheet described later. The resin composition layer 11 immediately after drying under the conditions of 125 ° C. × 1 hour is defined as W ₀ [g], and the resin after being placed in an atmosphere at a temperature of 25 ° C. and a humidity of 50% RH for 24 hours. When the weight of the composition layer 11 is W ₁ [g], it is determined using the following formula A.
_{WA1 (%) = {(W} 1 - W 0) / W 0} × 100 ··· formula A

  Further, the water absorption rate (moisture absorption rate) of the resin composition layer 11 before curing may be more than 0.0% and 1.2% or less, but more than 0.0% and 1.1% or less. Is more preferable, and more preferably more than 0.0% and not more than 1.0%. Thereby, the effects as described above can be more remarkably exhibited.

Further, the water absorption WA2 (%) after curing of the resin composition layer 11 is referred to as a resin composition layer 11 provided in the conductive connection sheet 1 manufactured by the method for manufacturing a conductive connection sheet described later. The weight of the resin composition layer 11 immediately after drying under the condition of 180 ° C. × 1 hour is defined as W ₀ [g], and the resin composition is disposed in an atmosphere at a temperature of 85 ° C. and a humidity of 85% RH for 24 hours. When the weight of the physical layer 11 is W ₂ [g], it is determined using the following formula B.
WA2 (%) = {(W ₂ −W ₀ ) / W ₀ } × 100 Expression B

  Further, the water absorption rate (moisture absorption rate) of the resin composition layer 11 after curing may be more than 0.0% and 2.5% or less, but more than 0.0% and 2.3% or less. Is more preferable, and more preferably more than 0.0% and 2.1% or less. Thereby, the effects as described above can be more remarkably exhibited.

  The water absorption rate (moisture absorption rate) of the resin composition layer 11 has a curable resin component, a thermoplastic resin component, a film-forming resin component, and a flux function among the resin compositions constituting the resin composition layer 11 described above. By appropriately setting the type and content of the compound, curing agent, curing accelerator, silane coupling agent, plasticizer, stabilizer, tackifier, lubricant, antioxidant, antistatic agent, etc., as described above It can be reliably set within the range.

  Specifically, for example, when an epoxy resin and a phenol resin are selected as the curable resin component, or when a phenoxy resin, an acrylic resin, or a polyimide resin is selected as the film-forming resin, the water absorption of the resin composition layer 11 Since the rate can be reduced, the water absorption rate of the resin composition layer 11 can be easily set within the range as described above.

  Further, if the resin composition layer 11 includes an inorganic filler in addition to the curable resin component, the water absorption before the resin composition layer 11 is cured exceeds 0.0%, .2% or less, and the water absorption after curing is more easily set within the range of more than 0.0% and 2.5% or less. This is because the water absorption rate of the resin composition layer 11 as a whole is relatively lowered due to a decrease in the content (occupancy) of the curable resin component in the resin composition layer 11. Inferred.

  Such inorganic fillers are not particularly limited, but include, for example, silicates such as talc, fired clay, unfired clay, mica, glass, oxides such as titanium oxide, alumina, silica, and fused silica, calcium carbonate , Carbonates such as magnesium carbonate and hydrotalcite, hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide, sulfates or sulfites such as barium sulfate, calcium sulfate and calcium sulfite, zinc borate, and metaborate Borates such as barium oxide, aluminum borate, calcium borate and sodium borate, nitrides such as aluminum nitride, boron nitride, silicon nitride and carbon nitride, titanates such as strontium titanate and barium titanate Use one of these or a combination of two or more of them. Kill.

  The particle size of the inorganic filler is not particularly limited, but the average particle size is preferably 5.0 μm or less, and the average particle size is more preferably about 0.01 to 3.0 μm.

  Further, the content of the inorganic filler is not particularly limited, but is added to such an extent that the function as the resin composition layer 11 is not lowered. Specifically, in the resin composition layer 11, about 1 to 60% by weight. It is preferable that it is about 5 to 30 weight%. Thereby, even when the inorganic filler is caught between the opposing terminals 21, conduction can be ensured reliably, and the water absorption rate before the resin composition layer 11 is cured exceeds 0.0%, .2% or less, and the water absorption after curing is more easily set within the range of more than 0.0% and 2.5% or less.

  Further, by providing a cover sheet for protecting the resin composition layers 11 and 13 on both surfaces of the conductive connection sheet 1, it is possible to accurately suppress or prevent moisture from reaching the resin composition layers 11 and 13. Therefore, the water absorption before curing of the resin composition layer 11 can be set more easily within the range of more than 0.0% and 1.2% or less.

The water vapor permeability of such a cover sheet is preferably 30 g / m ² · 24 hrs · 25 μm thickness · 40 ° C. · 90% RH or less, preferably 10 g / m ² · 24 hrs · 25 μm thickness · 40 ° C. · 90% RH or less. More preferably.

  Examples of the cover sheet having such water vapor permeability include polyolefin resins such as polyethylene and polypropylene, blend resins of these polyolefin resins, polyester resins such as polyethylene terephthalate, polyvinylidene chloride, vinyl chloride-vinylidene chloride copolymer, and the like. And a film containing metal foil or metal foil such as aluminum film, aluminum laminate film, and the like.

<< metal layer 12 >>
The metal layer (metal foil layer) 12 is a layer composed of a metal foil composed of a low melting point metal material.

  Such a metal layer 12 melts when heated to a melting point or higher, and when the resin composition layer 11 includes a compound having a flux function, due to the action of the compound having a flux function included in the resin composition layer 11, Since the oxide film formed on the surface of the metal layer 12 is reduced, the wettability of the molten metal layer 12 is improved. Therefore, the metal layer 12 selectively aggregates between the terminals 21 and 41, and finally, the connection portion 81 is formed by the solidified material.

  Here, in the present invention, a low melting point metal material having a melting point of 330 ° C. or lower, preferably 300 ° C. or lower, more preferably 280 ° C. or lower, further preferably 260 ° C. or lower is appropriately selected. Thereby, in the connection between the terminals 21 and 41 in the semiconductor device 10, it is possible to accurately suppress or prevent the various members of the semiconductor device 10 from being damaged by the thermal history.

  Further, from the viewpoint of ensuring the heat resistance of the semiconductor device 10 after the connection portion 81 is formed, that is, after the connection between the terminals 21 and 41, the low melting point metal material has a melting point of 100 ° C. or higher, preferably 110 ° C. As described above, a material having a temperature of 120 ° C. or higher is appropriately selected.

  Note that the melting point of the low melting point metal material, that is, the metal layer 12, can be measured by a differential scanning calorimeter (DSC).

  Such a low-melting-point metal material has the above-described melting point, and further, as long as the oxide film formed on the surface of the metal layer 12 can be removed by the reducing action of the compound having a flux function. For example, tin (Sn), lead (Pb), silver (Ag), bismuth (Bi), indium (In), zinc (Zn), nickel (Ni), antimony (Sb), iron (Fe) , An alloy of at least two kinds of metals selected from the group consisting of aluminum (Al), gold (Au), germanium (Ge) and copper (Cu), or a simple substance of tin.

  Among these alloys, as a low melting point metal material, considering its melting temperature, mechanical properties, etc., an Sn—Pb alloy, an Sn—Bi alloy that is a lead-free solder, an Sn—Ag—Cu alloy It is preferably composed of an alloy containing Sn, such as an alloy, an Sn—In alloy, or an Sn—Ag alloy.

  When an Sn—Pb alloy is used as the low melting point metal material, the tin content is preferably 30% by weight or more and less than 100% by weight, and preferably 35% by weight or more and less than 100% by weight. More preferably, it is more preferably 40% by weight or more and less than 100% by weight. When lead-free solder is used, the content of tin is preferably 15% by weight or more and less than 100% by weight, more preferably 20% by weight or more and less than 100% by weight, and more preferably 25% by weight or more and 100% by weight. More preferably, it is less than% by weight.

  Specifically, for example, Sn-37Pb (melting point 183 ° C.) is used as an Sn—Pb alloy, and Sn-3.0Ag-0.5Cu (melting point 217 ° C.), Sn-3.5Ag is used as a lead-free solder. (Melting point 221 ° C), Sn-58Bi (melting point 139 ° C), Sn-9.0Zn (melting point 199 ° C), Sn-3.5Ag-0.5Bi-3.0In (melting point 193 ° C), Au-20Sn (melting point) 280 ° C.).

  The thickness of the metal layer 12 is not particularly limited, but is appropriately set according to the gap between the opposing terminals 21 and 41, the separation distance between the adjacent terminals 21 and 41, and the like.

  For example, as in this embodiment, in the connection between the terminals 21 and 41 in the semiconductor device 10, the thickness of the metal layer 12 is preferably 0.5 μm or more, more preferably 3 μm or more, and 5 μm. More preferably, it is 100 μm or less, more preferably 50 μm or less, and further preferably 20 μm or less. If the thickness of the metal layer 12 is less than the lower limit, unconnected terminals 21 and 41 may be generated due to a shortage of the metal material constituting the metal layer 12, and if the upper limit is exceeded, adjacent terminals due to surplus metal material. 21 and 41 may cause a bridge due to the connecting portion 81 to cause a short circuit.

  The method for producing the metal layer 12 is not particularly limited, and examples thereof include a method for producing from a lump such as an ingot by rolling, a method for forming the resin layer 11 directly by vapor deposition, sputtering, plating, and the like.

  Further, in the conductive connection sheet 1, the amount of the low melting point metal material described above, that is, the occupation amount of the metal layer 12 is preferably 5% by weight or more in the conductive connection sheet 1, and is 20% by weight or more. More preferably, it is more preferably 30% by weight or more. Moreover, it is preferable that it is less than 100 weight%, It is more preferable that it is 80 weight% or less, It is further more preferable that it is 70 weight% or less.

  If the blending amount of the metal material in the conductive connection sheet 1, that is, the occupation amount of the metal layer 12 is less than the lower limit, there is a possibility that unconnected terminals 21 and 41 are generated due to a shortage of the metal material constituting the metal layer 12. If the upper limit is exceeded, a surplus of the metal material may cause bridging by the connecting portion 81 between the adjacent terminals 21 and 41, which may cause a short circuit.

  Alternatively, the occupation amount of the metal layer 12 may be defined by a volume ratio with respect to the conductive connection sheet 1. For example, the occupation amount (blending amount) of the metal layer 12 is preferably 1% by volume or more, more preferably 5% by volume or more, and more preferably 10% by volume or more with respect to the conductive connection sheet 1. Further preferred. Moreover, it is preferable that it is 90 volume% or less, It is more preferable that it is 80 volume% or less, It is further more preferable that it is 70 volume% or less. If the occupied amount of the metal layer 12 is less than the lower limit, there is a possibility that unconnected terminals 21 and 41 may be generated due to a shortage of the metal material constituting the metal layer 12, and if the upper limit is exceeded, the metal layer 12 is adjacent due to surplus metal material. There is a possibility that a bridge is formed between the terminals 21 and 41 by the connecting portion 81 and a short circuit occurs.

  In the present embodiment, as shown in FIG. 2, the case where the metal layer 12 is formed on the entire surface of the resin composition layer 11 has been described. However, the present invention is not limited to this, and the metal layer 12 is a flat surface. The shape is not particularly limited as long as it is formed on at least a part of the resin composition layer 11 in view.

  That is, when the metal layer is formed on a part of the resin composition layer 11 in plan view, a certain shape may be repeatedly formed in a pattern, or the shape may be irregular. A regular shape and an irregular shape may be mixed.

  Specifically, as shown in FIG. 3, a metal layer 12 patterned into various shapes is formed on the resin composition layer 11. For example, the shape of the metal layer 12 may be a dotted pattern (a), a striped pattern (b), a polka dot pattern (c), a rectangular pattern (d), a checkered pattern (e), a frame shape ( f), lattice pattern shape (g), multiple frame shape (h) and the like. These shapes are examples, and these shapes can be combined or deformed depending on the purpose and application.

  In addition, the method for producing the repetitive patterned metal layer is not particularly limited, but a method of punching a metal foil formed in a planar shape into a predetermined pattern, a method of forming a predetermined pattern by etching, etc. A method of forming by vapor deposition, sputtering, plating or the like by using a mask or the like can be mentioned.

  In addition, the conductive connection sheet 1 having the above-described configuration is used to heat and form the conductive connection sheet 1 in the connection portion and sealing layer formation method and the connection terminal and reinforcement layer formation method described later. In this case, voids remain in the sealing layer 80 and the reinforcing layer 86 even when sufficient adhesion between the resin composition layer 11 and the metal layer 12 is not obtained. However, it has been found by the study of the present inventor.

  As a result of further studies, the present inventor sets the surface free energy of the resin composition layer 11 to A [mN so that sufficient adhesion can be obtained between the resin composition layer 11 and the metal layer 12. / m], and when the surface free energy of the metal layer 12 is B [mN / m], the resin composition layer 11 and the metal can be satisfied so that A / B can satisfy the relationship of 0.5 to 1.5. It has been found that the above-mentioned problems can be solved by appropriately selecting the constituent materials included in the layer 12.

  Here, the surface free energy A [mN / m] of the resin composition layer 11 is obtained by, for example, dropping water and diiodomethane droplets on the surface of the resin composition layer 11 to determine the contact angle of each droplet. Based on the measured contact angle, it can be determined using the Owens-Wendt equation.

  More specifically, first, a resin composition layer (for example, a thickness of 30 μm) 11 formed on a copper plate or the like is prepared, and water and diiodomethane droplets (1.5 μL) are formed on the resin composition layer 11. ).

  Next, 20 seconds after dropping onto the resin composition layer 11, the contact angles of 10 droplets of water and diiodomethane are measured with, for example, a solid-liquid interface analyzer (“DropMaster 500” manufactured by Kyowa Interface Science Co., Ltd.). To determine the average value.

And the surface free energy A ((gamma) _s ) of the resin composition layer 11 can be calculated | required using the following formula 1 and the following formula 2.

(1 + COSθ) γ _l · / 2 =
(Γ _s ^d · γ _l ^d ) ^1/2 +2 (γ _s ^p · γ _l ^p ) ^1/2 ...
γ _s = γ _s ^d + γ _s ^p Equation 2
[In each formula, θ represents the contact angle, γ _s represents the surface free energy of the resin composition layer 11, γ _l represents the surface free energy of the droplets, d represents the dispersion force component, and p represents the polar force component. ]

  Further, the surface free energy B [mN / m] at the joint surface of the metal layer 12 is the same as that obtained for the surface free energy A at the joint surface of the resin composition layer 11. And a droplet of diiodomethane are dropped, the contact angle of each droplet is measured, and the Owens-Wendt equation can be obtained based on the measured contact angle.

  In the present invention, it is determined from the surface free energy A [mN / m] at the joint surface of the resin composition layer 11 and the surface free energy B [mN / m] at the joint surface of the metal layer 12 derived as described above. When the ratio A / B satisfying the relationship of 0.5 to 1.5 is satisfied, the conductive connection sheet is heated in the method for forming the connection portion and the sealing layer and the method for forming the connection terminal and the reinforcing layer. When these are formed, it is possible to accurately suppress or prevent the voids from remaining in the sealing layer 80 and the reinforcing layer 86, and to provide sufficient insulation between the adjacent terminals 21 and 41 and the connection terminals 85. It will be possible to secure. Moreover, when the cover sheet which protects the resin composition layer 11 is provided in the conductive connection sheet 1, peeling occurs at the interface between the resin composition layer 11 and the metal layer 12 when the cover sheet is peeled off. Can be reliably prevented.

  Moreover, A / B which is ratio of the surface free energy A [mN / m] of the resin composition layer 11 and the surface free energy B [mN / m] of the metal layer 12 should just be 0.5-1.5. However, it is preferable that it is about 0.6-1.4, and it is more preferable that it is about 0.7-1.3. Thereby, when the conductive connection sheet 1 is heated to form the connection portion and the sealing layer, and the connection terminal and the reinforcing layer, voids remain in the sealing layer 80 and the reinforcing layer 86. It can be suppressed or prevented accurately. Furthermore, when the cover sheet for protecting the resin composition layer 11 is provided on the conductive connection sheet 1, peeling occurs at the interface between the resin composition layer 11 and the metal layer 12 when the cover sheet is peeled off. It can prevent more reliably.

  In order to set the value of A / B within the above range, for example, it can be easily carried out by appropriately adjusting polar components such as a curable resin component, a compound having a flux activator, and a film-forming resin. .

  Specifically, for example, as the compound having a flux function contained in the resin composition layer 11, among those described above, the aliphatic carboxylic acid represented by the formula (1), the formula (2), or the formula The aromatic carboxylic acid represented by (3) is selected, and the metal layer 12 is mainly composed of an Sn-37Pb alloy (melting point 183 ° C.) or an Sn-3.0Ag-0.5Cu alloy (melting point 217 ° C.). It is preferable to select one. If the combination of the compound having a flux function contained in the resin composition layer 11 and the metal material contained in the metal layer 12 is the above combination, the value of A / B is reliably set to 0.5 to It can be set within the range of 1.5.

  The form of the conductive connection sheet 1 as described above is appropriately set according to the form of the resin composition constituting the resin composition layer 11 and the like.

  For example, when the curable resin composition is in a liquid state, the metal layer 12 is prepared, the curable resin composition is applied to both surfaces thereof, and this is semi-cured (B-staged) at a predetermined temperature. The material layer 11 can be used as the conductive connection sheet 1. In addition, a curable resin composition is applied on a release substrate such as a polyester sheet, and this is formed into a film for the purpose of semi-curing (B-stage) at a predetermined temperature, and then peeled off from the release substrate to form a metal. What was laminated on the layer 12 and formed on a film can be used as the conductive connection sheet 1.

  When the curable resin composition is solid, a resin composition varnish dissolved in an organic solvent is applied onto a release substrate such as a polyester sheet, and dried at a predetermined temperature to obtain a resin composition layer 11. After that, the metal layer 12 bonded together can be used as the conductive connection sheet 1. Moreover, what formed the metal layer 12 on the resin composition layer 11 obtained by carrying out similarly to the above using methods, such as vapor deposition, and made it into the film form can also be provided as the electrically conductive connection sheet 1. FIG.

  The metal layer 12 may be embossed for the purpose of improving the adhesion with the resin composition layer 11.

  The thickness of the conductive connection sheet 1 is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, further preferably 5 μm or more, and preferably 200 μm or less. 150 μm or less is more preferable, and 100 μm or less is further preferable. When the thickness of the conductive connection sheet 1 is within the above range, the gap between the adjacent terminals 21 and 41 can be sufficiently filled with the sealing layer 80 made of the resin composition. In addition, the mechanical adhesive strength after curing or solidification of the curable resin component and the electrical connection between the opposing terminals can be sufficiently ensured. In addition, it is possible to manufacture a connection terminal according to the purpose and application.

  In the present embodiment, when an oxide film is formed on the metal layer 12 and the terminals 21 and 41, the first resin composition layer 11 and the second resin are used for the purpose of removing the oxide film. Although it has been described that the resin composition constituting the composition layer 13 preferably contains a compound having a flux function, the resin composition contains an antioxidant instead of the compound having a flux function. It may be included.

<Method for producing conductive connection sheet>
Next, the conductive connection sheet 1 having the above-described configuration can be manufactured by, for example, the following manufacturing method.

(I) When the resin component forms a liquid at 25 ° C. When the resin composition constituting the first resin composition layer 11 and the second resin composition layer 13 forms a liquid at 25 ° C., first, a metal Layer 12 is prepared.
This metal layer 12 can be manufactured by rolling from a lump such as an ingot, for example.

  Next, by impregnating the metal layer 12 in a liquid resin composition, the liquid resin composition is adhered to both surfaces of the metal layer 12, and then the resin composition is semi-cured at a predetermined temperature. The conductive connection sheet 1 in which the resin composition layers 11 and 13 are formed on both surfaces of the metal layer 12 can be manufactured.

  When the thickness of the resin composition layers 11 and 13 to be formed needs to be controlled, the metal layer 12 immersed in the liquid resin composition is passed through a bar coater having a certain gap, By spraying the liquid resin composition onto the metal layer 12 with a spray coater or the like, the resin composition layers 11 and 13 having a target thickness can be easily manufactured.

(Ii) When the resin component forms a film at 25 ° C. When the resin composition constituting the first resin composition layer 11 and the second resin composition layer 13 forms a film at 25 ° C., A release substrate such as a polyester sheet is prepared.

  Next, a varnish obtained by dissolving the resin composition in an organic solvent is applied onto a release substrate, and then dried at a predetermined temperature to form a film-like resin composition.

  Next, two film-like resin compositions obtained by the above-mentioned process are prepared, and the metal layer 12 that has been produced in advance is laminated between these film-like resin compositions with a hot roll. By doing so, the conductive connection sheet 1 in which the resin composition layers 11 and 13 are formed on both surfaces of the metal layer 12 can be manufactured.

  In addition, when using the wound metal layer 12, the metal layer 12 is used as a base substrate, and the above-described film-shaped resin composition is laminated on both sides of the metal layer 12 using a hot roll. Thus, the wound conductive connection sheet 1 can be obtained.

  Furthermore, when using the wound metal layer 12, the varnish obtained as described above is directly applied to both surfaces of the metal layer 12, and then the solvent is stripped and dried to form the wound metal layer 12. The conductive connection sheet 1 can be obtained.

  When producing a conductive connection sheet having a patterned metal layer, first, for example, a metal layer that forms a sheet is disposed on a release substrate, and the metal layer is formed using a mold from the metal layer side. Half-cutting removes the extra metal layer to form a patterned metal layer.

  Next, the film-like resin composition obtained by the above-described method is placed on the surface of the metal layer opposite to the release substrate, and in this state, the laminate is laminated using a hot roll, and then the release substrate. Is peeled off from the metal layer.

  Furthermore, the film-like resin composition obtained by the above-described method is placed on the surface of the metal layer from which the release substrate is peeled, and laminated in this state using a hot roll, so that the both sides of the metal layer are laminated. A conductive connection sheet on which the resin composition layer is formed can be produced.

  In addition, the manufacturing method of an electroconductive connection sheet is not limited to the method mentioned above, The manufacturing method of an electroconductive connection sheet can be suitably selected according to the objective and a use.

  The conductive connection sheet 1 as described above is used for forming the connection portion 81 and the sealing layer 80 included in the semiconductor device 10.

  The connection method between terminals of the present invention or the method of forming connection terminals of the present invention is applied to the formation of the connection portion 81 and the sealing layer 80 using the conductive connection sheet 1.

<Connection method between terminals of the present invention>
Below, the case where the connection part 81 and the sealing layer 80 are formed first by applying the connection method between the terminals of this invention is explained in full detail.

  FIG. 4 is a longitudinal sectional view for explaining a method of manufacturing a connection portion and a sealing layer included in a semiconductor device using the connection method between terminals of the present invention, and FIG. 5 is based on JIS Z 3197. It is a longitudinal cross-sectional view for demonstrating the method to measure the wetting spread rate of a metal ball. In the following description, the upper side in FIG. 4 is referred to as “upper” and the lower side is referred to as “lower”.

  In the method for forming the connection portion 81 and the sealing layer 80 described below (the connection method between terminals of the present invention), an arrangement step of arranging the conductive connection sheet 1 between the opposing terminals 21 and 41, and the conductive connection sheet 1 And a curing step for curing the resin composition.

  That is, in the method for forming the connection portion 81 and the sealing layer 80 of the present embodiment, an arrangement step of arranging the conductive connection sheet 1 between the semiconductor chip 20 and the interposer 30 provided with the terminals 41, and a metal layer The heating step of heating the conductive connection sheet 1 at a temperature not lower than the melting point of 12 and at which the curing of the curable resin composition constituting the resin composition layers 11 and 13 is not completed, and the curing of the curable resin composition is completed. Curing step.

Hereinafter, each process is explained in full detail.
[1] Arrangement Step First, the semiconductor chip 20 and the interposer 30 provided with the terminals 41 are prepared.

  Next, the conductive connection sheet 1 is thermocompression bonded to the surface on the terminal 41 side of the interposer 30 using an apparatus such as a roll laminator or a press.

  In this state, the semiconductor chip 20 and the interposer 30 are aligned so that the terminals 21 and the terminals 41 included in the semiconductor chip 20 and the interposer 30 face each other, as shown in FIG.

  Thus, the conductive connection sheet 1 is disposed between the semiconductor chip 20 and the interposer 30 in a state where the terminals 21 and the terminals 41 face each other.

  As shown in FIG. 4A, the conductive connection sheet 1 is not limited to being thermocompression bonded to the interposer 30 side, and may be thermocompression bonded to the semiconductor chip 20 side. It may be thermocompression bonded.

[2] Heating Step Next, in the placement step [1], the conductive connection sheet 1 placed between the semiconductor chip 20 and the interposer 30 is replaced with the metal layer 12 as shown in FIG. Heat above the melting point.

  The heating temperature may be equal to or higher than the melting point of the metal layer 12. For example, the range in which the metal material can move in the curable resin composition by adjusting the heating time such as shortening the heating time, that is, “curable resin”. The upper limit is not particularly limited as long as it is in the range where the curing of the composition is not completed.

  Specifically, the heating temperature is preferably 5 ° C. or more higher than the melting point of the metal layer 12, more preferably 10 ° C. or more, and even more preferably 20 ° C. or more. It is particularly preferable that the temperature be 30 ° C. or higher.

  Specifically, the heating temperature is appropriately set depending on the composition of the metal layer 12 and the curable resin composition to be used, but is preferably 100 ° C. or higher, more preferably 130 ° C. or higher, and 140 More preferably, it is 150 degreeC or more, and it is most preferable that it is 150 degreeC or more. The heating temperature is preferably 260 ° C. or lower, more preferably 250 ° C. or lower, and 240 ° C. or lower from the viewpoint of preventing thermal deterioration of the semiconductor chip 20 and interposer 30 to be connected. More preferably it is.

  When the conductive connection sheet 1 is heated at such a temperature, the metal layer 12 is melted, and the molten metal layer 12, that is, the low melting point metal material can move in the resin composition layers 11 and 13.

  At this time, when a compound having a flux function is included in the curable resin composition, even if an oxide film is formed on the surface of the metal layer 12 due to the reducing action of the compound having the flux function, It is removed by being reduced. Therefore, the molten metal material is in a state in which the wettability is enhanced and the metal bonding is promoted, so that the molten metal material is likely to be aggregated between the terminals 21 and 41 arranged opposite to each other.

  Further, even if an oxide film is formed on the surfaces of the terminals 21 and 41, this oxide film is also removed by the reducing action of the compound having a flux function, and its wettability is enhanced. As a result, metal bonding with the metal material is promoted, and from this point of view, the molten metal material is easily aggregated between the terminals 21 and 41 arranged to face each other.

  In the present invention, since the metal layer 12 has a layer shape (foil shape), when the molten metal layer 12 is divided into a plurality of pieces and aggregates on the surfaces of the terminals 21 and 41, a part of the metal layer 12 is formed. It is possible to accurately suppress or prevent the resin composition layers 11 and 13 from remaining in the terminal 41 without aggregating. Therefore, it is possible to reliably prevent the occurrence of a leakage current due to a part of the metal layer 12 remaining in the sealing layer 80.

  From the above, the molten metal material moves through the curable resin component and selectively aggregates between the terminals 21 and 41. As a result, as shown in FIG. 4C, a connection part 81 made of a metal material is formed between the terminals 21 and 41, and the terminal 21 and the terminal 41 are electrically connected via the connection part 81. Connected. At this time, the sealing layer 80 is formed by surrounding the connection portion 81 and filling with the curable resin composition. As a result, insulation between the adjacent terminals 21 and 41 is ensured, so that a short circuit between the adjacent terminals 21 and 41 is prevented.

  Note that even if the distance between the adjacent terminals 21 and 41 is a narrow pitch, the adjacent metal terminals 21 and 41 are selectively agglomerated between the adjacent terminals 21 and 41 so that the adjacent terminals are adjacent to each other. In order to accurately suppress or prevent the occurrence of leakage current between 21 and 41, it is important to maintain the flux activity amount of the resin composition contained in the resin composition layers 11 and 13 at high activity. It has been found by the study of the present inventor.

  As a result of further studies by the present inventors, in a state where at least a part of metal balls made of a low melting point metal material is disposed in the resin composition layers 11 and 13, the “soldering” specified in JIS Z 3197 is specified. In accordance with “Resin-based flux test method”, the resin ball is heated so as to have a melting temperature of 37% or more when heated to the melting temperature of the metal ball and then the wet spreading rate of the metal ball is measured. If the constituent materials included in the composition layers 11 and 13 are selected as appropriate, between the terminals 21 and 41 due to the fact that the molten metal material is not selectively aggregated between the terminals 21 and 41 facing each other. It has been found that the occurrence of leakage current can be suppressed or prevented accurately.

Here, the wetting and spreading rate S [%] of the metal ball in accordance with the soldering resin flux test method specified in JIS Z 3197 is determined by the diameter D [mm] of the metal ball before melting by heating and the heating The height H [mm] of the metal ball after melting by is measured, and can be obtained from these values using the following formula 1.
S [%] = (D−H) / D × 100 Formula 1

  More specifically, first, a copper plate (for example, length 1.0 cm × width 1.0 cm × thickness 0.3 mm) 90 is prepared, and a resin composition layer 11 having a thickness of 3050 μm is formed on the copper plate 90. After that, a metal ball 91 having a diameter D of 0.5 mm is further disposed on the resin composition layer 11 (see FIG. 5A).

  The metal ball 91 used for obtaining the wet spread rate of the metal ball is not particularly limited, but is mainly composed of an Sn-37Pb alloy (melting point 183 ° C.) or an Sn-3.0Ag-0.5Cu alloy (melting point 217 ° C.). It is preferable to use one. Using a metal ball 91 composed of such an alloy, when the wet spread rate is 37% or more, a molten metal material is placed between the opposing terminals 21 and 41. It can be aggregated more selectively. As a result, the occurrence of a leak current between the adjacent terminals 21 and 41 is accurately prevented or suppressed.

  Next, the metal balls 91 arranged on the resin composition layer 11 are crimped by using a thermocompression bonding apparatus (for example, “TMV1-200ABS” manufactured by Tsukuba Mechanics Co., Ltd.), so that at least a part of the metal balls 91 is bonded. And embedded in the resin composition layer 11 (see FIG. 5B).

  Note that it is sufficient that at least a part of the metal ball 91 is embedded in the resin composition layer 11 by pressure bonding of the metal ball 91, but 1/30100 to 1/310 of the diameter D [mm] of the metal ball 91. It is preferable that the degree is embedded, and it is more preferable that about 1/2050 to 1/10 is embedded. If the metal ball 91 is embedded in the resin composition layer 11 within such a range, the oxide film formed on the metal ball 91 is removed by the compound having a flux function contained in the resin composition layer 11. Can do.

  Moreover, the conditions at the time of thermocompression bonding the metal ball 91 to the resin composition layer 11 are not particularly limited, but for example, the load is set to 50 N, the temperature is 80 ° C., and the time is 5 seconds.

  Next, the metal ball 91 is brought into a molten state by heating the metal ball 91 to a temperature higher than the melting point of the low melting point metal material constituting the metal ball 91 (see FIG. 5C).

  The temperature at which the metal ball 91 is heated may be higher than the melting point of the metal material. For example, the temperature is preferably higher by 10 ° C. than the melting point of the 30 metal material, and about 30 ° C. higher than the melting point of the metal material. More preferably.

  The time for heating the metal ball 91 is preferably 5 seconds or more, and more preferably about 20 seconds.

  By setting the conditions for heating the metal ball 91 within this range, the entire metal ball 91 can be almost uniformly melted.

  Here, the molten metal ball 91 is formed by removing the oxide film formed on the surface thereof by the reducing action of the compound having the flux function contained in the resin composition layer 11, resulting in the copper plate 90. It will spread over the top. Therefore, in the resin composition layer 11, when the compound having the flux function sufficiently exhibits its reducing action, it sufficiently spreads on the copper plate 90, and on the contrary, sufficiently exhibits its reducing action. If not, the copper plate 90 will not be sufficiently wetted and spread.

  Next, after the molten metal ball 91 is cooled and solidified, the resin composition layer 11 is dissolved in a solvent to be removed from the copper plate 90 (see FIG. 5D).

  In addition, as a solvent, the thing similar to what was mentioned as a solvent used when preparing curable resin composition in curable resin composition (a) mentioned above can be used.

  Next, the height H [mm] of the metal ball 91 exposed on the copper plate 90 by removing the resin composition layer 11 is measured, and the wet spread rate S [%] of the metal ball is calculated using the above formula 1. ].

  In the present invention, when the wet spread rate S of the metal ball derived from the above formula 1 is 37% or more as described above, the compound having the flux function is sufficiently reduced in the resin composition layer 11. It can be said that the oxide film formed on the metal layer 12 can be surely removed by the reducing action. As a result, the molten metal material can be reliably agglomerated between the terminals 21 and 41 facing each other, so that the occurrence of a leakage current between the adjacent terminals 21 and 41 is accurately prevented or suppressed. Become so.

  Further, the wet spreading rate S may be 37% or more, but is preferably 50% or more, and more preferably 55% or more. As a result, the molten metal material can be more reliably aggregated between the terminals 21 and 41 facing each other, and the sealing layer 80 is caused by excessively containing a compound having a flux function. It is possible to accurately suppress or prevent a decrease in moisture resistance.

Further, as a result of further studies by the present inventors, the wet spreading rate of the metal balls 91 has a correlation with the acid value amount of the resin composition layer 11, and the acid value amount of the resin composition layer 11 is 3 It has been found that the wetting and spreading rate of the metal balls 91 can be more reliably set to 37% or more when it is 0.0 × 10 ^{−5 to} 1.0 × 10 ⁻² mol / g.

  Here, in this specification, the acid value amount of the resin composition layer 11 can be determined in accordance with “Petroleum products and lubricating oil-neutralization number test method” defined in JIS K 2501.

Specifically, the acid value of the resin composition layer 11 is prepared by preparing a resin composition solution in which the resin composition M (about 0.2 g) constituting the resin composition layer 11 is dissolved in acetone (100 mL). This resin composition solution is titrated with a sodium hydroxide aqueous solution C (0.05 mol / L) by potentiometric titration, and an automatic potentiometric titrator (for example, “AT-500N” manufactured by Kyoto Electronics Industry Co., Ltd.) is used. To measure the titration curve. And from the drop amount (titer) A [L] up to the end point (inflection point) of the sodium hydroxide aqueous solution when the inflection point on the obtained titration curve is set as the end point, the following formula 2 is used. Can be calculated.
Acid value [mol / g] = (A × C) / M Equation 2

The acid value of the resin composition layer 11 is preferably a ^{3.0 × 10 -5 ~1.0 × 10 -2} mol / g, 8 × 10 -5 ~5 × 10 -2-3 mol / More preferably, it is g. Thereby, the wet spreading rate of the metal balls 91 can be set to 37% or more more reliably.

Further, in the resin composition layer 11, that is, the resin composition, the compounding amount of the compound having a flux function is slightly different depending on the type of the compound having the flux function to be selected, but is preferably about 1 to 50 wt%. It is more preferably about 2 to 40 wt%, and particularly preferably about 3 to 25 wt%. Thereby, the acid value amount of the resin composition layer 11 can be reliably set within the range of 3.0 × 10 ^{−5 to} 1.0 × 10 ⁻² mol / g.

  Furthermore, as the compound having a flux function, among the compounds described above, the aliphatic carboxylic acid represented by the formula (1) and the aromatic carboxylic acid represented by the formula (2) or the formula (3) are mentioned. Preferably used. By selecting such a compound as a compound having a flux function, the acid value of the resin composition layer 11 can be more reliably set within the above range.

  In the method of forming the connection part 81 and the sealing layer 80 using the conductive connection sheet 1 as described above, the connection part 81 is formed by selectively agglomerating the heated and melted metal material between the terminals 21 and 41, A sealing layer 80 made of a curable resin composition can be formed around the periphery. As a result, the insulation between the adjacent terminals 21 and 41 can be secured and the occurrence of leakage current can be reliably prevented, so that the connection reliability of the connection via the connection portion 81 between the terminals 21 and 41 is improved. Can do.

  In addition, even in a fine wiring circuit, electrical connection between a large number of terminals 21 and 41 can be performed collectively. Furthermore, in the next step [3], the mechanical strength of the connection portion 81 and the sealing layer 80 can be increased by curing the curable resin composition.

  In this step [2], the semiconductor chip 20 and the interposer 30 may be heated in a pressurized state so that the distance between the opposing terminals 21 and 41 is reduced. For example, the distance between the terminals 21 and 41 facing each other can be increased by heating and pressurizing the semiconductor chip 20 and the interposer 30 in FIG. Since it can be controlled to be constant, it is possible to increase the electrical connection reliability by the connecting portion 81 between the opposing terminals 21 and 41.

  Furthermore, when applying pressure or heating, an ultrasonic wave or an electric field may be applied, or special heating such as laser or electromagnetic induction may be applied.

[3] Curing Step Next, in the heating step [2], after forming the connecting portion 81 and the sealing layer 80, the sealing layer 80 is fixed by curing the curable resin composition.

  Thereby, both the electrical reliability by the connection part 81 between the terminals 21 and 41 and the mechanical reliability by the sealing layer 80 are fully securable.

  In particular, in this embodiment, since the curable resin composition having a high insulation resistance value at the time of high melt viscosity is used, the insulation of the sealing layer (insulating region) 80 can be more reliably ensured.

  Curing of the curable resin composition can be carried out by heating the curable resin composition. The curing temperature of the curable resin composition can be appropriately set according to the composition of the curable resin composition. Specifically, the temperature is preferably at least 5 ° C. lower than the heating temperature in the heating step [2], and more preferably at least 10 ° C. lower. More specifically, it is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, further preferably 130 ° C. or higher, and most preferably 150 ° C. or higher. Moreover, it is preferable that it is 300 degrees C or less, It is more preferable that it is 260 degrees C or less, It is more preferable that it is 250 degrees C or less, It is most preferable that it is 240 degrees C or less. When the curing temperature is within the above range, the curable resin composition can be sufficiently cured while reliably preventing the conductive connection sheet 1 from being thermally decomposed.

  Through the steps as described above, the connection portion 81 and the sealing layer 80 are formed between the semiconductor chip 20 and the interposer 30.

  In the present embodiment, the case where the connection portion 81 is formed and electrically connected between the terminal 21 and the terminal 41 provided in the semiconductor chip 20 and the interposer 30, respectively, is described. However, the present embodiment is limited to this case. However, the present invention can be applied to a case where terminals included in electronic components included in various electronic devices are electrically connected. Examples of the electronic components include a semiconductor wafer, a rigid substrate, and a flexible substrate.

<Method for Forming Connection Terminal of the Present Invention>
Next, the case where the connection part 81 and the sealing layer 80 are formed using the connection terminal forming method of the present invention will be described.

  In this case, first, the connection terminal 85 and the reinforcing layer 86 are formed on the surface on the terminal 21 side of the semiconductor chip 20 by applying the connection terminal forming method of the present invention, and then the connection terminal 85 and the reinforcing layer 86. By connecting (mounting) the semiconductor chip 20 provided with to the surface of the interposer 30 on the side of the terminal 41, the connecting portion 81 and the sealing layer 80 are formed.

  Hereinafter, a method for forming the connection terminal 85 and the reinforcing layer 86 on the surface on the terminal 21 side of the semiconductor chip 20 by applying the connection terminal forming method of the present invention will be described in detail.

  FIG. 6 is a longitudinal sectional view for explaining a method of forming connection terminals corresponding to terminals provided in a semiconductor chip using the connection terminal formation method of the present invention. In the following description, the upper side in FIG. 6 is referred to as “upper” and the lower side is referred to as “lower”.

  In the method of forming the connection terminal 85 and the reinforcing layer 86 described below, an arrangement step of arranging the conductive connection sheet 1 on a surface on the terminal 21 side of the semiconductor chip 20 and a heating step of heating the conductive metal sheet 1 are performed. Have.

  That is, in the method of forming the connection terminal 85 and the reinforcing layer 86 of the present embodiment, the disposing step of disposing the conductive connection sheet 1 on the surface of the semiconductor chip 20 on the terminal 21 side, the melting point of the metal layer 12 or higher, A heating step of heating the conductive connection sheet 1 at a temperature at which the curing of the curable resin composition constituting the resin composition layers 11 and 13 is not completed.

Hereinafter, each process is explained in full detail.
[1] Arrangement Step First, as shown in FIG. 6A, a semiconductor chip 20 having terminals 21 on the lower surface side is prepared.

  Next, the conductive connection sheet 1 is thermocompression-bonded (arranged) to the surface on the terminal 21 side of the semiconductor chip 20 using an apparatus such as a roll laminator or a press.

  Thereby, the conductive connection sheet 1 comes into contact with the terminal 21 exposed on the surface of the semiconductor chip 20 on the terminal 21 side.

[2] Heating step Next, in the placement step [1], the conductive connection sheet 1 (metal layer 12) placed on the surface on the terminal 21 side of the semiconductor chip 20 is as shown in FIG. Heating is performed at a temperature equal to or higher than the melting point of the metal layer 12.

  The temperature for heating the conductive connection sheet 1 is set to the same temperature as the temperature for heating the conductive connection sheet 1 in the heating step [2] of the first embodiment.

  When the conductive connection sheet 1 is heated at such a temperature, the metal layer 12 is melted, and the molten metal layer 12, that is, the low melting point metal material can move in the resin composition layers 11 and 13.

  At this time, when a compound having a flux function contained in the curable resin composition is included, even if an oxide film is formed on the surface of the metal layer 12 due to the reducing action of the compound having the flux function, this oxidation is performed. The film is removed by being reduced. Therefore, the molten metal material is in a state in which wettability is enhanced and metal bonding is promoted, so that the molten metal layer 12 tends to aggregate on the surface of the terminal 21.

  Further, even if an oxide film is formed on the surface of the terminal 21, this oxide film is also removed by the reducing action of the compound having a flux function, and its wettability is enhanced. As a result, metal bonding with the metal material is promoted, and from this point of view, the molten metal layer 12 easily aggregates on the surface of the terminal 21.

  In the present invention, since the metal layer 12 has a layer shape (foil shape), when the molten metal layer 12 is divided into a plurality of pieces and aggregates on the surface of the terminal 21, a part of the metal layer 12 is a terminal 21. It can be accurately suppressed or prevented from remaining in the resin composition layers 11 and 13 without agglomerating. Therefore, it is possible to reliably prevent the occurrence of a leakage current due to a part of the metal layer 12 remaining in the reinforcing layer 86.

  From the above, the molten metal material moves in the resin composition layers 11 and 13, that is, in the curable resin component, and selectively aggregates on the surface of the terminal 21. When the conductive connection sheet 1 is cooled in this state, a connection terminal 85 made of a solidified metal material is formed on the surface of the terminal 21 as shown in FIG. At this time, the reinforcing layer 86 is formed by surrounding the connection terminal 85 and being filled with the curable resin composition. As a result, insulation between the adjacent connection terminals 85 is ensured, so that a short circuit between the adjacent connection terminals 85 is reliably prevented.

  In the method for forming the connection terminal 85 and the reinforcing layer 86 as described above, the metal material heated and melted is selectively aggregated on the terminal 21 to form the connection terminal 85, and the periphery thereof is made of a curable resin composition. A reinforcing layer 86 can be formed. As a result, insulation between adjacent connection terminals 85 can be ensured.

  Further, even in the semiconductor chip 20 having a plurality of terminals 21 at a fine pitch, a plurality of connection terminals 85 can be collectively formed corresponding to the terminals 21.

  In this step [2], the conductive connection sheet 1 and the semiconductor chip 20 may be heated in a pressurized state so that the distance between the conductive connection sheet 1 and the terminal 21 is reduced. For example, the conductive connection sheet 1 and the terminal 21 are heated and pressed using means such as a known thermocompression bonding device in a direction in which the conductive connection sheet 1 and the semiconductor chip 20 in FIG. Since the distance can be controlled to be constant, it is possible to further enhance the aggregating ability of the molten metal material on the surface of the terminal 21.

  Furthermore, when applying pressure or heating, an ultrasonic wave or an electric field may be applied, or special heating such as laser or electromagnetic induction may be applied.

  The connection terminal 85 and the reinforcing layer 86 are formed through the process [1] and the process [2] as described above. That is, the method for forming the connection terminal and the reinforcing layer of the present invention is applied to the arranging step [1] and the heating step [2] for forming the connecting terminal 85 and the reinforcing layer 86.

  In addition, when using a curable resin component as a resin component contained in the resin composition layers 11 and 13 as in this embodiment, in the heating step [2], the curable resin composition is not completely cured. It is preferable to keep the state. Thus, when the semiconductor chip 20 provided with the connection terminals 85 and the reinforcing layer 86 is mounted on the surface of the interposer 30 on the terminal 41 side, the reinforcing layer 86 is heated to be in a molten state again. Will be able to.

  By connecting the semiconductor chip 20 provided with the connection terminal 85 and the reinforcing layer 86 on the surface of the interposer 30 on the terminal 41 side, the connection terminal 85 and the reinforcing layer 86 are heated to connect the semiconductor chip 20. Since the terminal 85 is in a molten state again, the connection portion 81 and the sealing layer 80 can be formed between the semiconductor chip 20 and the interposer 30 by cooling thereafter.

  And in this embodiment, since the curable resin component is contained as a resin component contained in the resin composition layers 11 and 13 and this is not fully cured, the curable resin composition is sufficiently used. The sealing layer 80 is fixed by curing. Thereby, the mechanical strength of the connection part 81 and the sealing layer 80 can be raised.

  Through the steps described above, the connection terminal 85 is formed on the surface of the semiconductor chip 20 on which the terminal 21 is provided, and the reinforcing layer 86 is formed so as to surround the connection terminal 85.

  In the present embodiment, the case where the connection terminal forming method of the present invention is applied to the case where the connection terminal 85 is formed so as to correspond to the terminal 21 included in the semiconductor chip 20 has been described. However, the present embodiment is limited to this case. First, it can be applied to the case where connection terminals (bumps) are formed on terminals (electrodes) included in electronic components used in various electronic devices. Examples of various electronic components include semiconductor wafers and flexible substrates. Can be mentioned.

  As described above, the conductive connection sheet, the connection method between terminals, the formation method of the connection terminal, the semiconductor device, and the electronic device of the present invention have been described, but the present invention is not limited to these.

  For example, the configuration of each part of the conductive connection sheet of the present invention can be replaced with an arbitrary one that can exhibit the same function, or an arbitrary configuration can be added.

  Moreover, arbitrary processes may be added to the connection method between terminals and the formation method of a connection terminal of this invention as needed.

Next, specific examples of the present invention will be described.
1. Evaluation method In the terminal connection body produced in order to connect the terminals which oppose using the conductive connection sheet of each Example and a comparative example, connection resistance between terminals, conduction path (connection part) formability, other than conduction paths The presence or absence of a metal layer remaining in the sealing layer located in the region, the presence or absence of voids, and the HAST test were measured or evaluated by the following methods.

(1) Connection resistance The resistance between opposing terminals in the obtained terminal connection body was determined by a four-terminal method (resistance meter: manufactured by Iwasaki Tsushinki Co., Ltd., “Digital Multimeter VOA7510”, measurement probe: Hioki Electric Co., Ltd.) 12 points were measured by “Pin type lead 9771” manufactured by the manufacturer, and when the average value was less than 30 mΩ, it was determined as “A”, and when it was 30 mΩ or more, “B” was determined.

(2) Conducting path forming property With respect to 10 sets of opposing terminals in the obtained terminal connection body, the cross section between the terminals was observed with a scanning electron microscope ("JSM-7401F" manufactured by JEOL Ltd.), “A” indicates that a cylindrical conductive path (connecting portion) is formed by solder in all 10 sets, and “B” indicates that there is a terminal in which no conductive path is formed even in one set, which are adjacent. The case of short contact with the terminal was determined as “C”.

(3) Presence or absence of residual metal layer The cross section of the obtained terminal connector was observed with a scanning electron microscope (SEM) (manufactured by JEOL Ltd., model number “JSM-7401F”), and all metal layers (metal materials) were observed. "A" when contributing to the formation of a conduction path between opposing terminals, a part of the metal layer in the resin (sealing layer) other than between the opposing terminals (connection part) without contributing to the formation of the conduction path Was left as “B”.

(4) Presence or absence of voids The obtained terminal connection body was observed with an ultrasonic flaw detector (SAT) (manufactured by Hitachi Construction Machinery Finetech Co., Ltd., “mi-scope 10”). The case of less than 10% was judged as “A”, and the case of 10% or more was judged as “B”.

(5) HAST test The resin composition prepared to obtain the conductive connection sheet of each example and comparative example was applied to a comb-like copper circuit (gap between adjacent circuits 20 μm) at 120 ° C., 0.2 MPa, 30 seconds. Then, the resin composition was cured by heating at 180 ° C. for 1 hour, and five HAST test samples were prepared. The obtained HAST test sample was exposed to an atmosphere of 130 ° C. and 85% RH, a voltage of 10 V was applied to the comb-shaped copper circuit, and the insulation resistance between adjacent copper circuits was measured in situ. “A” when the insulation resistance is 1.0 × 10 ⁻⁶ Ω or more in all samples by 100 hours after treatment, and insulation resistance is less than 1.0 × 10 ⁻⁶ Ω by 100 hours after treatment The case where there was at least one sample was determined as “B”.

2. Measurement of Water Absorption Rate WA1 of Resin Composition Layer Before Curing The water absorption rate WA1 [%] of the resin composition layer provided in the conductive connection sheets of Examples and Comparative Examples described below was determined as follows.

That is, first, the weight W ₀ [g] of the resin composition layer immediately after drying the resin composition layer included in the produced conductive connection sheet under the condition of 125 ° C. × 1 hour was measured.

Next, the weight W ₁ [g] of the resin composition layer after the conductive connection sheet was placed in an atmosphere of a temperature of 25 ° C. and a humidity of 50% RH for 24 hours was measured.

Then, using the above formula A from the measured _W 0 [g] and _W 1 [g], it was calculated water absorption WA1 [%].

3. Measurement of water absorption WA2 of the resin composition layer after curing The water absorption WA2 [%] of the resin composition layer provided in the conductive connection sheets of Examples and Comparative Examples described below was determined as follows.

That is, first, the weight W ₀ [g] of the resin composition layer immediately after being dried on the condition of 180 ° C. × 1 hour of the resin composition layer included in the produced conductive connection sheet was measured.

Next, the weight W ₂ [g] of the resin composition layer after the conductive connection sheet was placed in an atmosphere of a temperature of 85 ° C. and a humidity of 85% RH for 24 hours was measured.

Then, using the above formula B from the measured _W 0 [g] and _W 2 [g], was calculated water absorption WA2 [%].

4). Preparation of conductive connection sheet [Examples 1 to 5, comparative example]
First, bisphenol A type epoxy resin (manufactured by Dainippon Ink and Chemicals, "EPICLON-840S", epoxy equivalent 185 g / eq) is used as an epoxy resin, and phenol novolac resin (manufactured by Sumitomo Bakelite, "PR-" is used as a curing agent. 53647 ") as a film-forming resin, a modified biphenol type epoxy resin (manufactured by Japan Epoxy Resin," YX-6654 ", film-forming resin 1), an acrylic ester copolymer (manufactured by Nagase ChemteX Corporation," SG-P3 ", film-forming resin 2), 6,6 nylon (manufactured by Ube Industries," P2020 ", film-forming resin 3) as a compound having a flux function, sebacic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) As a silane coupling agent, 2- (3,4-epoxycyclohexyl) Lutrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM-303”) as a curing accelerator, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., “Curesol 2P4MZ”), silica as an inorganic filler Particles (manufactured by Admatech, “SE2050”, average particle size 0.5 μm, specific gravity 2.2) were prepared.

  And it prepares by mixing the resin composition for forming the resin composition layer with which the conductive connection sheet of each Example and a comparative example is equipped with a compounding ratio as shown in Table 1 for every Example and a comparative example. did.

Next, as the metal layer, solder foil A (Sn / Pb = 63/37 (weight ratio), melting point: 183 ° C., density: 8.4 g / cm ³ , thickness 10 μm) and solder foil B (Sn / Ag / Cu = 96.5 / 3.0 / 0.5 (weight ratio), melting point: 217 ° C., density = 7.4 g / cm ³ , thickness 10 μm) were prepared.

  For each of the examples and comparative examples, as shown in Table 1, the metal layer of solder foil A or solder foil B is selected, and the resin composition prepared for each of the examples and comparative examples is applied to both surfaces of the metal layer. After applying (supplying), by drying, a conductive connection sheet provided with a resin composition layer having a thickness of 50 μm on both surfaces of the metal layer was produced.

5. Connection Between Terminals Using Conductive Connection Sheet Next, connection between opposing terminals was performed using the conductive connection sheets of the examples and comparative examples.

  More specifically, first, the substrate is composed of an FR-4 base material (thickness 0.1 mm) and a circuit layer (copper circuit, thickness 12 μm), and Ni / Au plating (thickness 3 μm) is applied on the copper circuit. Two devices having a formed connection terminal (terminal diameter: 100 μm, center distance between adjacent terminals: 300 μm) were prepared.

  Next, for each of the examples and the comparative examples, the conductive connection sheets of the examples and the comparative examples are arranged between the substrates having such a configuration. ) Was subjected to thermocompression bonding (inter-substrate gap of 50 μm) under the conditions shown in Table 1 to form a connecting portion between the opposing terminals, thereby electrically connecting the terminals. Then, the resin composition was hardened by heating at 180 degreeC for 1 hour, and the terminal connection body was obtained.

  Next, with respect to the obtained terminal connection body, using the evaluation method described above, the connection resistance between the terminals facing each other, the formation of the conduction path between the terminals, the presence or absence of residual solder in the insulating region and the presence or absence of voids are described above. Evaluation was made according to the method. The results are shown in Table 1.

6). Preparation of HAST Test Sample First, a HAST test sample was prepared according to the procedure described in the HAST test evaluation method described above, using the resin compositions prepared to obtain the conductive connection sheets of the examples and comparative examples. did.

  Next, the obtained HAST test sample was evaluated according to the evaluation method of the HAST test described above. The results are shown in Table 1.

  As shown in Table 1, in each Example, the water absorption WA1 before curing of the resin composition layer is more than 0.0% and 1.2% or less, and the water absorption WA2 after curing is 0.0%. It was possible to set within the range of more than 2.5%.

  Then, by setting the water absorption rates WA1 and WA2 within such a range, in each embodiment, the connection portion is selectively formed between the facing terminals without leaving the metal material in the sealing layer. In addition, it was found that generation of voids in the sealing layer could be accurately prevented, and excellent results were obtained for each evaluation.

  In contrast, in the comparative example, the water absorption WA1 before curing of the resin composition layer is in the range of more than 0.0% and 1.2% or less, and the water absorption WA2 after curing is more than 0.0%. , 2.5% or less could not be set. For this reason, the metal material remains in the sealing layer, and voids are generated in the sealing layer. Each evaluation is clearly inferior to each example.

DESCRIPTION OF SYMBOLS 1 Conductive connection sheet 10 Semiconductor device 11 1st resin composition layer 12 Metal layer 13 2nd resin composition layer 20 Semiconductor chip 21 Terminal 30 Interposer 41 Terminal 70 Bump 80 Sealing layer 81 Connection part 85 Connection terminal 86 Reinforcement Layer 90 Copper plate 91 Metal ball

Claims (16)

A conductive connection sheet composed of a laminate comprising a resin composition layer containing a curable resin component and a metal layer composed of a low melting point metal material,
The water absorption before curing of the resin composition layer is more than 0.0% and 1.2% or less, and the water absorption after curing is more than 0.0% and 2.5% or less. Conductive connection sheet.   The conductive resin sheet according to claim 1, wherein the resin composition layer includes a resin composition containing the curable resin component and a compound having a flux function.   The conductive connection sheet according to claim 2, wherein the compound having a flux function contains a compound having at least one of a phenolic hydroxyl group and a carboxyl group. The conductive connection sheet according to claim 2 or 3, wherein the compound having the flux function contains a compound represented by the following general formula (1).
_{HOOC- (CH 2) n-COOH} ····· (1)
(In Formula (1), n is an integer of 1-20.) The conductive connection sheet according to claim 2 or 3, wherein the compound having the flux function contains at least one of compounds represented by the following general formula (2) and the following general formula (3).

[Wherein, R ^{1 to} R ⁵ are each independently a monovalent organic group, and at least one of R ^{1 to} R ⁵ is a hydroxyl group. ]

[Wherein, R ^{6 to} R ²⁰ are each independently a monovalent organic group, and at least one of R ^{6 to} R ²⁰ is a hydroxyl group or a carboxyl group. ]   In the said resin composition, content of the compound which has the said flux function is 1 to 50 weight%, The electrically conductive connection sheet in any one of Claim 2 thru | or 5.   The metal layer includes tin (Sn), lead (Pb), silver (Ag), bismuth (Bi), indium (In), zinc (Zn), nickel (Ni), antimony (Sb), iron (Fe), 7. An alloy of at least two metals selected from the group consisting of aluminum (Al), gold (Au), germanium (Ge), and copper (Cu), or a simple substance of tin. Conductive connection sheet.   The conductive connection sheet according to claim 7, wherein the metal layer is composed of a Sn—Pb alloy, a Sn—Ag—Cu alloy, or a Sn—Ag alloy as a main material.   The conductive connection sheet according to claim 8, wherein the metal layer is composed mainly of a Sn-37Pb alloy or a Sn-3.0Ag-0.5Cu alloy.   Furthermore, the said resin composition layer is an electroconductive connection sheet in any one of the Claims 1 thru | or 9 containing an inorganic filler.   The conductive connection sheet according to claim 1, wherein the resin composition layer and the metal layer are bonded to each other.   The laminate is composed of two resin composition layers and one metal layer, and the resin composition layer, metal layer, and resin composition layer are laminated in this order. The conductive connection sheet according to any one of 11.   An arrangement step of arranging the conductive connection sheet according to any one of claims 1 to 12 between opposing terminals, the conductive material at a temperature that is equal to or higher than a melting point of the metal material and does not complete the curing of the resin composition. A method for connecting terminals, comprising: a heating step for heating the connection sheet; and a curing step for curing the resin composition.   An arrangement step of arranging the conductive connection sheet according to any one of claims 1 to 12 on an electrode of an electronic member, the melting point of the metal material, and a temperature at which the curing of the resin composition is not completed And a heating step of heating the conductive connection sheet.   Opposite terminals are electrically connected to each other through a connection portion formed using the conductive connection sheet according to any one of claims 1 to 12.   Opposite terminals are electrically connected through a connection portion formed using the conductive connection sheet according to any one of claims 1 to 12.

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