JP2010278331A - Circuit board, and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a circuit board sufficiently suppressed in occurrence of a void in an adhesive layer between circuit members, having each area between pitches sufficiently sealed and filled, and excelling in connection reliability; and a method of manufacturing the same. <P>SOLUTION: In this circuit board, a first circuit member having a first projecting electrode of a height t<SB>c</SB>and solder of a height t<SB>m</SB>formed on the first projecting electrode and a second circuit member having a second projecting electrode of a height t<SB>s</SB>are arranged by facing the first projecting electrode to the second projecting electrode; an adhesive layer of a thickness t<SB>2</SB>is interposed between the first projecting electrode and the second projecting electrode which are arranged oppositely to each other; and the first projecting electrode and the second projecting electrode which are arranged oppositely to each other are electrically connected to each other to satisfy the following expressions (1), (2) and (3) by heating and pressurizing them: t<SB>1</SB>&ge;t<SB>c</SB>+t<SB>s</SB>(1); t<SB>1</SB>&times;1.3&ge;t<SB>2</SB>&gt;t<SB>c</SB>+t<SB>m</SB>(2); t<SB>1</SB>&times;1.3&ge;t<SB>2</SB>&gt;t<SB>c</SB>+t<SB>s</SB>(3). In the expressions, t<SB>1</SB>, t<SB>c</SB>, t<SB>s</SB>, t<SB>2</SB>and t<SB>m</SB>are the distance along the lamination direction between the first circuit member and the second circuit member after the heating and the pressurizing, the height of the first projecting electrode, the height of the second projecting electrode, the thickness of the adhesive layer before the heating and the pressurizing, and the height of the solder formed on the first projecting electrode, respectively. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  Circuit board and circuit board manufacturing method.

  In recent years, with the miniaturization and thinning of electronic devices, the density of circuits formed on circuit members has increased, and the distance between adjacent electrodes and the width of electrodes tend to be very narrow. Along with this, there is an increasing demand for thinner and smaller semiconductor packages. Therefore, as a semiconductor chip mounting method, instead of the conventional wire bonding method that uses metal wires to connect, protruding electrodes called bumps are formed on the chip electrodes, and the substrate electrodes and chip electrodes are directly connected via the bumps. The flip chip connection method is attracting attention.

  Known flip-chip connection methods include a method using solder bumps, a method using gold bumps and a conductive adhesive, a thermocompression bonding method, and an ultrasonic method. In these methods, there is a problem that the connection reliability is lowered because thermal stress derived from the difference in thermal expansion coefficient between the chip and the substrate is concentrated on the connection portion. In order to prevent such a decrease in connection reliability, an underfill that fills the gap between the chip and the substrate is generally formed of a resin. Since thermal stress is relieved by dispersion in the underfill, connection reliability can be improved.

  As a method for forming an underfill, a method is generally known in which a liquid resin is injected into a gap between a chip and a substrate after the chip and the substrate are connected (see Patent Document 1). Also, underfill formation is completed in the process of connecting the chip and the substrate using a film-like resin such as an anisotropic conductive adhesive film (hereinafter referred to as ACF) or a nonconductive adhesive film (hereinafter referred to as NCF). The method of making it known is also known (refer patent document 2).

  On the other hand, through silicon vias (TSV: Through Silicon Via), which is a three-dimensional mounting technology for connecting chips at the shortest distance, has recently attracted attention as enabling higher functionality and higher speed operation (non-patent literature). 1). As a result, it has been demanded that the thickness of the semiconductor wafer be as thin as possible and the mechanical strength not be lowered.

  In accordance with the demand for further thinning of the semiconductor device, so-called back grinding is performed to grind the back surface of the wafer in order to make the semiconductor wafer thinner, and the manufacturing process of the semiconductor device is complicated. . Therefore, as a method suitable for simplifying the process, a resin having a function of holding a semiconductor wafer during back grinding and an underfill function has been proposed (see Patent Documents 3 and 4).

Japanese Patent Laid-Open No. 2000-10082 JP 2003-142529 A JP 2001-332520 A JP 2005-028734 A

  However, with the thinning of the semiconductor device, the gaps between the connection portions and the pitch between the terminals are becoming even narrower, resulting in insufficient wetting at the interface due to insufficient flow of the film-like resin at the time of connection and foaming of the film-like resin. Due to the generation of voids, etc., the filling of the film-like resin between the pitches becomes insufficient, and the connection reliability may be lowered.

  In addition, in the face-down bonding method in which solder bumps are formed on the electrode portions of the semiconductor chip and the semiconductor chip is directly connected to the circuit board by solder bonding, an oxide film formed on the solder surface is formed in order to obtain good electrical bonding. There is a need to remove. However, in the conventional method, when solder bonding is performed by heating in a short time, the flux activity for removing the oxide film on the surface of the solder cannot be obtained, the solder wettability becomes insufficient, and the connection reliability is lowered. There is.

  The present invention has been made in view of the above circumstances, and the occurrence of voids in the adhesive layer between circuit members is sufficiently suppressed, the pitch is sufficiently sealed, and the circuit is excellent in connection reliability. It aims at providing a board and the manufacturing method of the said circuit board.

To solve the above problems, the present invention includes a first circuit member having a solder height t height t _m which is formed on the first projecting electrodes and said first protruding electrode on the _c, height and a second circuit member having a second projecting electrodes of t _s, the first protruding electrode and the second protruding electrode are arranged to face, the first projection electrode and the facing arranged first second is interposed an adhesive layer having a thickness of t ₂ between the protrusion electrodes, by heating and pressing, the following formula (1), (2) and (3) the first projection electrodes opposed to satisfy And a circuit board in which the second protruding electrode is electrically connected.
_{t 1 ≧ t c + t s} (1)
t ₁ × 1.3 ≧ t ₂ > t _c + t _m (2)
t ₁ × 1.3 ≧ t ₂ > t _c + t _s (3)
[Where t ₁ represents the distance along the stacking direction between the first circuit member and the second circuit member after heating and pressing, and t _c represents the height of the first protruding electrode. , T _s indicates the height of the second protruding electrode, t ₂ indicates the thickness of the adhesive layer before heating and pressing, and t _m indicates the height of the solder formed on the first protruding electrode. Show. ]

  According to the circuit board of the present invention, by electrically connecting the first protruding electrode and the second protruding electrode that are arranged to face each other so as to satisfy the above formulas (1), (2), and (3), the circuit Generation of voids in the adhesive layer between the members is sufficiently suppressed, and the space between the pitches is sufficiently sealed and filled. In addition, since the solder spreads along both the protruding electrodes at the solder joint portion between the first protruding electrode and the second protruding electrode, the circuit board has excellent connection reliability that can withstand repeated heat tests.

  In the circuit board of the present invention, the adhesive layer comprises (A) a thermoplastic resin, (B) a thermosetting resin, (C) a latent curing agent, (D) an inorganic filler, and (E) an organic material. An adhesive layer made of an adhesive composition containing fine particles and (F) a powder compound that is solid at room temperature and has a maximum particle size of 25 μm or less is preferable. By using the adhesive layer containing the components (A), (B), (C), (D) and (E), the embedding property at the time of connection is further improved, and the generation of voids can be further reduced. Furthermore, by blending component (F), the oxide film formed on the solder surface can be removed, and the solder wettability is improved.

  In the circuit board of the present invention, from the viewpoint of further improving solder wettability, the component (F) is at least one compound selected from a compound having a carboxyl group, a compound having a methylol group, and a hydrazide compound. It is preferable. Moreover, it is preferable that (B) component contains an epoxy resin from a viewpoint of improving heat resistance and adhesiveness.

The present invention also comprises a first circuit member having a solder height t height t _m which is formed on the first projecting electrodes and said first protruding electrode on the _c, the second height t _s A second circuit member having a projecting electrode is disposed so that the first projecting electrode and the second projecting electrode are opposed to each other, and between the first projecting electrode and the second projecting electrode disposed to face each other. The first protrusion electrode and the second protrusion are disposed so as to face each other so as to satisfy the following formulas (1), (2), and (3) by interposing an adhesive layer having a thickness of t _{2 on} Provided is a method for manufacturing a circuit board, in which electrodes are electrically connected.
_{t 1 ≧ t c + t s} (1)
t ₁ × 1.3 ≧ t ₂ > t _c + t _m (2)
t ₁ × 1.3 ≧ t ₂ > t _c + t _s (3)
[Where t ₁ represents the distance along the stacking direction between the first circuit member and the second circuit member after heating and pressing, and t _c represents the height of the first protruding electrode. , T _s indicates the height of the second protruding electrode, t ₂ indicates the thickness of the adhesive layer before heating and pressing, and t _m indicates the height of the solder formed on the first protruding electrode. Show. ]

  According to the method for manufacturing a circuit board of the present invention, the first protruding electrode and the second protruding electrode that are arranged to face each other so as to satisfy the above formulas (1), (2), and (3) are electrically connected. As a result, the generation of voids in the adhesive layer between the circuit members is sufficiently suppressed, and a circuit board in which the space between the pitches is sufficiently sealed can be obtained. In addition, according to the method for manufacturing a circuit board of the present invention, since the solder spreads along the two protruding electrodes at the solder joint portion between the first protruding electrode and the second protruding electrode, it can withstand repeated heat tests. A circuit board with excellent connection reliability can be obtained.

  In the method for producing a circuit board of the present invention, the adhesive layer comprises (A) a thermoplastic resin, (B) a thermosetting resin, (C) a latent curing agent, (D) an inorganic filler, An adhesive layer made of an adhesive composition containing E) organic fine particles and (F) a powder compound that is solid at room temperature and has a maximum particle size of 25 μm or less is preferable. By using the adhesive layer containing the above components (A), (B), (C), (D) and (E), the adhesive layer can be more excellent in embedding at the time of connection and the generation of voids is further increased. Can be reduced. Furthermore, by blending component (F), the oxide film formed on the solder surface can be removed, and the solder wettability is improved.

  In the circuit board of the present invention, from the viewpoint of further improving solder wettability, the component (F) is at least one compound selected from a compound having a carboxyl group, a compound having a methylol group, and a hydrazide compound. It is preferable. Moreover, it is preferable that (B) component contains an epoxy resin from a viewpoint of improving heat resistance and adhesiveness.

  According to the present invention, it is possible to provide a circuit board in which void generation in an adhesive layer between circuit members is sufficiently suppressed, a space between pitches is sufficiently sealed, and which has excellent connection reliability, and a manufacturing method thereof. be able to.

1 is a schematic cross-sectional view showing a preferred embodiment of an adhesive sheet for connecting circuit members according to the present invention. 1 is a schematic cross-sectional view showing a preferred embodiment of an adhesive sheet for connecting circuit members according to the present invention. It is a schematic cross section for explaining one embodiment of a manufacturing method of a semiconductor device concerning the present invention. It is a schematic cross section for explaining one embodiment of a manufacturing method of a semiconductor device concerning the present invention. It is a schematic cross section for explaining one embodiment of a manufacturing method of a semiconductor device concerning the present invention. It is a schematic cross section for explaining one embodiment of a manufacturing method of a semiconductor device concerning the present invention. It is a schematic cross section for explaining one embodiment of a manufacturing method of a semiconductor device concerning the present invention.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of an adhesive sheet for connecting circuit members that is suitably used in the method for manufacturing a circuit board according to the present invention. An adhesive sheet 10 for connecting a circuit member shown in FIG. 1 is provided on a support base 3, an adhesive layer 2 made of an adhesive composition, and a protection covering the adhesive layer 2. Film 1 is provided.

  First, the adhesive composition of this embodiment which comprises the adhesive bond layer 2 is demonstrated.

  The adhesive composition of the present embodiment includes (A) a thermoplastic resin, (B) a thermosetting resin, (C) a latent curing agent, (D) an inorganic filler, (E) organic fine particles, (F) a powder compound that is solid at room temperature and has a maximum particle size of 25 μm or less.

  (A) As a thermoplastic resin, polyester resin, polyether resin, polyamide resin, polyamideimide resin, polyimide resin, polyvinyl butyral resin, polyvinyl formal resin, phenoxy resin, polyhydroxy polyether resin, acrylic resin, polystyrene resin, butadiene Examples thereof include resins, acrylonitrile / butadiene copolymers, acrylonitrile / butadiene / styrene resins, styrene / butadiene copolymers, and acrylic acid copolymers. These can be used alone or in admixture of two or more.

  The component (A) can improve the film forming property of the adhesive composition. Film-forming property indicates mechanical properties that do not easily tear, break, or stick when a liquid adhesive composition is solidified to form a film. If the film is easy to handle in a normal state (for example, room temperature), it can be said that the film formability is good. Among the thermoplastic resins described above, it is preferable to use a polyimide resin or a phenoxy resin because of excellent heat resistance and mechanical strength.

  The weight average molecular weight of the component (A) is preferably 20,000 to 800,000, more preferably 30,000 to 500,000, still more preferably 35,000 to 100,000, and 40,000 to 8 It is particularly preferable that the number is 10,000. When the weight average molecular weight is within this range, it becomes easy to satisfactorily balance the strength and flexibility of the adhesive layer 2 in the form of a sheet or film, and the flowability of the adhesive layer 2 becomes good. The circuit filling property (embedding property) of the wiring can be sufficiently secured. In the present specification, the weight average molecular weight is a value measured by gel permeation chromatography and converted using a standard polystyrene calibration curve.

  Moreover, from the viewpoint of imparting adhesiveness to the adhesive layer 2 before curing while maintaining film forming properties, the glass transition temperature of the component (A) is preferably 20 to 170 ° C., more preferably. 25-120 ° C. When the glass transition temperature of the component (A) is less than 20 ° C., the film formability at room temperature is lowered, and the adhesive layer 2 tends to be deformed during the processing of the semiconductor wafer in the back grinding process. If it exceeds, the adhesive temperature when the adhesive layer 2 is applied to the semiconductor wafer needs to be higher than 170 ° C., so that the thermosetting reaction of the component (B) proceeds and the fluidity of the adhesive layer 2 decreases. As a result, poor connection tends to occur.

  (B) Examples of thermosetting resins include epoxy resins, unsaturated polyester resins, melamine resins, urea resins, diallyl phthalate resins, bismaleimide resins, triazine resins, polyurethane resins, phenol resins, cyanoacrylate resins, and polyisocyanate resins. , Furan resin, resorcinol resin, xylene resin, benzoguanamine resin, silicone resin, siloxane-modified epoxy resin, and siloxane-modified polyamideimide resin. These can be used alone or in admixture of two or more. From the viewpoint of improving heat resistance and adhesiveness, it is preferable to contain an epoxy resin as the component (B).

  The epoxy resin is not particularly limited as long as it is cured and has an adhesive action. For example, a wide range of epoxy resins described in the epoxy resin handbook (edited by Masaki Shinbo, Nikkan Kogyo Shimbun) can be used. it can. Specifically, for example, a bifunctional epoxy resin such as bisphenol A type epoxy, a novolac type epoxy resin such as a phenol novolac type epoxy resin or a cresol novolac type epoxy resin, or a trisphenolmethane type epoxy resin can be used. Moreover, what is generally known, such as a polyfunctional epoxy resin, a glycidyl amine type epoxy resin, a heterocyclic ring-containing epoxy resin, or an alicyclic epoxy resin, can be applied.

  (C) Examples of latent curing agents include phenolic, imidazole, hydrazide, thiol, benzoxazine, boron trifluoride-amine complexes, sulfonium salts, amine imides, polyamine salts, dicyandiamide, and organic peroxides. Mention may be made of system curing agents. From the viewpoint of extending the visible time, it is preferable to use, as the component (C), those encapsulated with a polymer substance, an inorganic substance, a metal thin film, or the like using these curing agents as a core and microencapsulated.

  The microcapsule-type latent curing agent comprises the above curing agent by coating with a polymer material such as polyurethane, polystyrene, gelatin and polyisocyanate, an inorganic material such as calcium silicate or zeolite, or a metal thin film such as nickel or copper. One whose core is substantially covered is mentioned.

  The average particle size of the microcapsule-type latent curing agent is preferably 10 μm or less, more preferably 5 μm or less. Such a microcapsule-type latent curing agent has a more uniform reaction start temperature, and the microcapsule-type latent curing agent The curing start temperature of the adhesive composition containing the latent curing agent is also uniform. Moreover, when average particle diameter becomes larger than 10 micrometers, the surface flatness at the time of hardening | curing an adhesive composition and shape | molding into a film form may not fully be obtained. If the surface flatness is not sufficient, there is a possibility that the gap between the pitches cannot be sufficiently sealed when used for connecting circuit members. Moreover, it is preferable that the lower limit of an average particle diameter is 1 micrometer or more. Such a microcapsule-type latent curing agent has high solvent resistance to the solvent used for the varnish during film formation, and can maintain the fluidity of the adhesive composition before heating and pressing for a long time.

  The content of the component (C) in the adhesive composition according to the present embodiment is preferably 4 to 40 parts by mass and 8 to 30 parts by mass with respect to 100 parts by mass of the component (B). More preferred. When the content of the component (C) is less than 4 parts by mass, the curing reaction tends to be difficult to proceed, and when it exceeds 40 parts by mass, the fluidity of the adhesive composition is lowered and the total amount of the adhesive composition is occupied. Since the ratio of the curing agent is excessively increased, the ratio of the thermosetting resin is relatively decreased, and characteristics such as heat resistance and adhesiveness tend to be deteriorated.

  The adhesive composition according to the present embodiment includes (D) an inorganic filler, so that the moisture absorption rate and the linear expansion coefficient of the cured adhesive layer 2 can be reduced and the elastic modulus can be increased. The connection reliability of the semiconductor device can be improved. As the component (D), an inorganic filler that does not reduce visible light transmittance can be selected in order to prevent visible light scattering in the adhesive layer 2 and improve visible light transmittance. As the component (D) capable of suppressing a decrease in visible light transmittance, an inorganic filler having a particle diameter finer than the wavelength of visible light is selected, or resin components (A), (B) and (C) It is preferable to select an inorganic filler having a refractive index close to the refractive index of a resin composition comprising the component (hereinafter sometimes referred to as “resin composition”).

  The inorganic filler having a particle diameter finer than the wavelength of visible light is not particularly limited as long as it is a transparent filler, and the average particle diameter is preferably less than 0.3 μm, preferably 0.1 μm or less. It is more preferable that The refractive index of the inorganic filler is preferably 1.46 to 1.7.

  As an inorganic filler having a refractive index approximate to the refractive index of the resin composition, after preparing a resin composition composed of the components (A), (B) and (C) and measuring the refractive index, An inorganic filler having an approximate refractive index can be selected. As the inorganic filler, it is preferable to use a fine filler from the viewpoint of filling the gap between the semiconductor chip of the adhesive layer 2 and the circuit board and suppressing the generation of voids in the connecting step. The average particle diameter of such an inorganic filler is preferably 0.01 to 5 μm, more preferably 0.1 to 2 μm, and still more preferably 0.3 to 1 μm. When the average particle size is less than 0.01 μm, the surface area of the particles increases, the viscosity of the adhesive composition increases, and it tends to be difficult to fill the inorganic filler.

  The refractive index of the inorganic filler having a refractive index approximate to the refractive index of the resin composition is preferably in the range of the refractive index ± 0.06 of the resin composition. For example, when the refractive index of the resin composition is 1.60, an inorganic filler having a refractive index of 1.54 to 1.66 can be suitably used. The refractive index can be measured using an Abbe refractometer with sodium D line (589 nm) as a light source. Examples of such inorganic fillers include composite oxide fillers, composite hydroxide fillers, barium sulfate, and clay minerals. Specifically, cordierite, forslite, mullite, barium sulfate, magnesium hydroxide, boric acid. Aluminum, barium or silica titania can be used.

  The two types of inorganic fillers described above may be used in combination. However, in order not to hinder the increase in the viscosity of the adhesive composition, the amount of the inorganic filler having a particle diameter finer than the wavelength of visible light is preferably less than 10% by mass based on the component (D). .

The component (D) is preferably 7 × 10 ⁻⁶ / ° C. or less in the temperature range of 0 to 700 ° C. from the viewpoint of improving the elastic modulus of the adhesive layer 2, and 3 × 10. More preferably, it is ⁻⁶ / ° C. or lower.

  The blending amount of the component (D) is preferably 25 to 200 parts by weight, and 50 to 150 parts by weight with respect to a total of 100 parts by weight of the components (A), (B) and (C). It is more preferable that it is 75 to 125 parts by mass. If the blending amount of the component (D) is less than 25 parts by mass, the linear expansion coefficient of the adhesive layer formed from the adhesive composition is increased and the elastic modulus is decreased. It is difficult to obtain a void suppressing effect at the time of connection. On the other hand, when the blending amount of component (D) exceeds 200 parts by mass, the melt viscosity of the adhesive composition increases, and the wettability of the interface between the semiconductor chip and the adhesive layer or the interface between the circuit board and the adhesive layer. As a result of the decrease, voids remain due to peeling or insufficient embedding.

  (E) Organic fine particles include, for example, acrylic resin, silicone resin, butadiene rubber, polyester, polyurethane, polyvinyl butyral, polyarylate, polymethyl methacrylate, acrylic rubber, polystyrene, NBR, SBR, silicone-modified resin, and the like as components. A copolymer is mentioned. As the organic fine particles, organic fine particles having a molecular weight of 1 million or more or organic fine particles having a three-dimensional crosslinked structure are preferable. Such organic fine particles have high dispersibility in the adhesive composition. Moreover, the adhesive composition containing such organic fine particles is further excellent in adhesiveness and stress relaxation property after curing. Here, “having a three-dimensional crosslinked structure” means that the polymer chain has a three-dimensional network structure, and the organic fine particles having such a structure include, for example, a polymer having a plurality of reaction points. It can be obtained by treating with a crosslinking agent having two or more functional groups capable of binding to the reaction site. It is preferable that both organic fine particles having a molecular weight of 1 million or more and organic fine particles having a three-dimensional crosslinked structure have low solubility in a solvent. These organic fine particles having low solubility in a solvent can obtain the above-described effects more remarkably. In addition, from the viewpoint of obtaining the above-described effect more remarkably, organic fine particles having a molecular weight of 1 million or more and organic fine particles having a three-dimensional crosslinked structure are (meth) acrylic acid alkyl-silicone copolymer, silicone- (meth). Organic fine particles made of an acrylic copolymer or a composite thereof are preferable.

  As the component (E), organic fine particles having a core-shell structure and having different compositions in the core layer and the shell layer can also be used. Specific examples of the core-shell type organic fine particles include particles obtained by grafting an acrylic resin with a silicone-acrylic rubber core, and particles obtained by grafting an acrylic resin with an acrylic copolymer as a core.

  In the case where the component (E) is an organic fine particle having a molecular weight of 1 million or more or an organic fine particle having a three-dimensional cross-linked structure, the solubility in an organic solvent is low. Can be blended. Therefore, the organic fine particles are dispersed in an island shape in the adhesive layer 2 after curing, and the strength of the connection body is improved. In addition, (E) component has a function as an impact-resistant relaxation agent which has stress relaxation property.

  (E) It is preferable that an average particle diameter is 0.1-2 micrometers. When the average particle size of the component (E) is less than 0.1 μm, the melt viscosity of the adhesive composition increases, and there is a tendency to prevent solder wettability at the time of connection, and when it exceeds 2 μm, the effect of reducing the melt viscosity decreases. It tends to be difficult to obtain a void suppression effect at the time of connection.

  (E) component, in order to give the adhesive layer 2 a void suppression at the time of connection and a stress relaxation effect after connection, 100 parts by mass of the total of (A), (B) and (C) components, It is preferable that it is 5-20 mass parts. If the blending amount of the component (E) is less than 5 parts by mass, the effect of suppressing voids at the time of connection tends to be difficult and the stress relaxation effect tends to be difficult to be exhibited. Solder wettability decreases and causes residual voids, and the elastic modulus of the cured product tends to be too low, leading to a decrease in connection reliability.

  (F) The powder compound that is solid at room temperature and has a maximum particle size of 25 μm or less is a compound containing at least one selected from a compound having a carboxyl group, a compound having a methylol group, and a hydrazide compound. The component (F) has a function as a solder wettability modifier. (Hereinafter, the component (F) is referred to as “solder wettability modifier”). That is, the component (F) has a melting point lower than the melting point of the solder, and after melting, is an oxide on the surface of a metal such as a circuit electrode. By removing, solder wettability of the adhesive layer 2 can be improved. Examples of the component (F) include acetylsalicylic acid, benzoic acid, benzylic acid, adipic acid, azelaic acid, benzylbenzoic acid, malonic acid, 2,2-bis (hydroxymethyl) propionic acid, salicylic acid, and m-hydroxybenzoic acid. , Succinic acid, 2,6-dimethoxymethyl paracresol, benzoic acid hydrazide, carbohydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, salicylic acid hydrazide, iminodiacetic acid dihydrazide, itaconic acid dihydrazide, citric acid trihydrazide, Examples include hydrazide, benzophenone hydrazone, 4,4′-oxybisbenzenesulfonyl hydrazide, and adipic acid dihydrazide. From the viewpoint of improving the dispersibility in the adhesive layer 2, it is preferable to use these compounds after pulverizing them with a mortar and pulverizing them, and then removing those having a large particle size with a filter of at least 25 μm. The maximum particle size of the component (F) is 25 μm or less, preferably 20 μm or less, and more preferably 10 μm or less.

  (F) It is preferable that melting | fusing point of a component is 100 degreeC or more, It is more preferable that it is 130-200 degreeC, It is still more preferable that it is 140-180 degreeC. When the melting point of the component (F) is less than 100 ° C., the powder compound as the component (F) is dissolved at the time of film formation (for example, when the resin composition solution is applied and dried when heated). Then, the storability of the resin composition may decrease, such as reacting with the component (B).

  The compounding amount of the component (F) is preferably 1 to 20 parts by mass and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the adhesive composition. If the blending amount of the component (F) is less than 1 part by mass, the effect of improving the solder wettability is not sufficient, and even if blended in excess of 20 parts by mass, the effect of improving the solder wettability is saturated, so that it becomes an excess component.

  Various coupling agents can be added to the adhesive composition according to this embodiment in order to modify the surface of the inorganic filler to improve the interfacial bond between different materials and increase the adhesive strength. Examples of the coupling agent include silane-based, titanium-based, and aluminum-based coupling agents. Among them, a silane-based coupling agent is preferable because it is highly effective.

  Examples of the silane coupling agent include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and 3-aminopropylmethyldisilane. Examples include ethoxysilane, 3-ureidopropyltriethoxysilane, and 3-ureidopropyltrimethoxysilane. These can be used alone or in combination of two or more.

  An ion scavenger can be added to the adhesive composition according to the present embodiment in order to adsorb ionic impurities and improve insulation reliability during moisture absorption. There are no particular restrictions on such ion scavengers, for example, triazine thiol compounds, bisphenol reducing agents, etc., compounds known as copper damage inhibitors to prevent ionization and dissolution, zirconium-based, antimony, etc. Examples include inorganic ion adsorbents such as bismuth-based magnesium aluminum compounds.

The adhesive composition suppresses temperature change after connecting the semiconductor chip and the circuit board, expansion due to heat absorption, etc., and achieves high connection reliability. The linear expansion coefficient at 60 ° C. is preferably 60 × 10 ⁻⁶ / ° C. or less, more preferably 55 × 10 ⁻⁶ / ° C. or less, and further preferably 50 × 10 ⁻⁶ / ° C. or less. When the linear expansion coefficient of the adhesive layer 2 after curing exceeds 60 × 10 ⁻⁶ / ° C., electricity between the connection terminals of the semiconductor chip and the wiring of the circuit board is caused by temperature change after mounting or expansion due to heat absorption. Connection may not be maintained.

  The adhesive layer 2 formed from the adhesive composition according to the present embodiment has a reaction rate of 60% or more measured by differential scanning calorimetry (hereinafter referred to as “DSC”) after heating at 250 ° C. for 10 seconds. It is preferable that it is 70% or more. Moreover, it is preferable that the reaction rate of the adhesive layer 2 measured by DSC is less than 10% after storing the circuit composition connecting composition sheet for 14 days at room temperature. Thereby, by using the adhesive composition according to the present embodiment, it is possible to obtain a film adhesive that is sufficiently excellent in reactivity at the time of connection and excellent in storage stability.

  The adhesive layer 2 preferably has an uncured visible light transmittance of 5% or more, more preferably a visible light transmittance of 8% or more, and a visible light transmittance of 10% or more. Is more preferable. If the visible light transmittance is less than 5%, the recognition mark cannot be identified by the flip chip bonder, and the alignment work tends to be impossible. On the other hand, there is no particular limitation on the upper limit of the visible light transmittance.

  The visible light transmittance can be measured using a Hitachi U-3310 spectrophotometer. For example, after a baseline correction measurement was performed using a Teijin DuPont PET film (Purex, 555 nm transmittance: 86.03%) having a thickness of 50 μm as a reference material, an adhesive layer 2 having a thickness of 25 μm was formed on the PET film. Thereafter, the transmittance in the visible light region of 400 to 800 nm is measured. Since the wavelength relative intensity of the halogen light source and light guide used in the flip chip bonder is the strongest at 550 to 600 nm, the transmittance of the adhesive layer 2 is compared using the transmittance at 555 nm in this specification. Yes.

  The adhesive layer 2 is obtained by dissolving or dispersing the adhesive composition according to the present embodiment in a solvent to form a varnish, and applying the varnish onto a protective film (hereinafter sometimes referred to as “first film”) 1. The film can be formed by removing the solvent by heating. Then, the support base material 3 is laminated | stacked at normal temperature-60 degreeC on the adhesive bond layer 2, and the adhesive sheet for circuit member connection of this invention can be obtained. Alternatively, the adhesive layer 2 can be formed by applying the varnish on the support substrate 3 and removing the solvent by heating.

  The solvent to be used is not particularly limited, but is preferably determined in consideration of the volatility at the time of forming the adhesive layer from the boiling point. Specifically, for example, a solvent having a relatively low boiling point such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, and xylene forms an adhesive layer. It is preferable in that the curing of the adhesive layer is difficult to proceed. These solvents can be used alone or in combination of two or more.

  As the protective film 1, plastic films, such as a polyethylene terephthalate, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polymethylpentene film, can be used, for example. From the viewpoint of peelability, it is also preferable to use a film having a low surface energy made of a fluororesin such as a polytetrafluoroethylene film as the protective film 1.

  In order to improve the peelability of the protective film 1, the surface of the protective film 1 on which the adhesive layer 2 is formed is treated with a release agent such as a silicone-based release agent, a fluorine-based release agent, or a long-chain alkyl acrylate-based release agent. It is preferable. As commercially available products, for example, “A-63” (release treatment agent: modified silicone type) or “A-31” (release treatment agent: Pt silicone type) manufactured by Teijin DuPont Films Ltd. Can do.

  The protective film 1 preferably has a thickness of 10 to 100 μm, more preferably 10 to 75 μm, and particularly preferably 25 to 50 μm. If the thickness is less than 10 μm, the protective film tends to be broken during coating, and if it exceeds 100 μm, the cost tends to be inferior.

  As a method of applying the varnish on the protective film 1 (or the supporting substrate 3), generally known methods such as knife coating, roll coating, spray coating, gravure coating, bar coating, curtain coating, and the like are used. Is mentioned.

  Although there is no restriction | limiting in particular in the thickness of the adhesive bond layer 2, 5-200 micrometers is preferable, It is more preferable that it is 7-150 micrometers, It is still more preferable that it is 10-100 micrometers. If the thickness is less than 5 μm, it will be difficult to ensure sufficient adhesion, and the convex electrodes of the circuit board will not be filled. If it is thicker than 200 μm, it will not be economical, and there will be a demand for miniaturization of the semiconductor device. It becomes difficult to respond to.

  Examples of the supporting substrate 3 include plastic films such as a polyethylene terephthalate film, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polymethylpentene film, a polyvinyl acetate film, a polyvinyl chloride film, and a polyimide film. Further, the support base 3 may be a mixture of two or more selected from the above materials, or a multilayer of the above film.

  Although the thickness of the support base material 3 does not have a restriction | limiting in particular, 5-250 micrometers is preferable. If the thickness is less than 5 μm, the support substrate may be cut during grinding (back grinding) of the semiconductor wafer, and if it is more than 250 μm, it is not economical, which is not preferable.

  The support base material 3 preferably has high light transmittance. Specifically, the minimum light transmittance in a wavelength region of 500 to 800 nm is preferably 10% or more.

  In addition, as the support base 3, a substrate in which an adhesive layer is laminated on the plastic film (hereinafter sometimes referred to as “second film”) can be used.

  FIG. 2 is a schematic cross-sectional view showing a preferred embodiment of the adhesive sheet for connecting circuit members according to the present invention. The adhesive sheet 11 for connecting a circuit member shown in FIG. 2 is provided on a support substrate 3 having a plastic film 3b and an adhesive layer 3a provided on the plastic film 3b, and on the adhesive layer 3a. An adhesive layer 2 made of the adhesive composition of the present invention and a protective film 1 covering the adhesive layer 2 are provided.

  In order to improve the adhesion between the second film 3b and the pressure-sensitive adhesive layer 3a, the surface of the second film is subjected to chemical treatment such as chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, ionizing radiation treatment, etc. Or you may give a physical process.

  The pressure-sensitive adhesive layer 3a has an adhesive force at room temperature, preferably has a necessary adhesion to an adherend, and is cured by high energy rays such as radiation or heat (that is, reduces the adhesive force). The thing provided with is preferable. The pressure-sensitive adhesive layer 3a can be formed using, for example, acrylic resin, various synthetic rubbers, natural rubber, or polyimide resin. The thickness of the pressure-sensitive adhesive layer 3a is usually about 5 to 20 μm.

  The above-mentioned adhesive sheets 10 and 11 for connecting a circuit member are interposed between a circuit member and a semiconductor element having circuit electrodes which are opposed to each other and soldered, or between semiconductor elements, and the circuit member and the semiconductor element or semiconductor. It can be used for bonding elements together. In this case, the circuit member and the semiconductor element or the semiconductor elements can be bonded together with sufficient adhesive force while suppressing generation of voids, and the circuit electrodes can be soldered well. Thereby, the connection body excellent in connection reliability can be obtained. Moreover, the adhesive sheet 10 and 11 for circuit member connection can also be used as an adhesive sheet in the lamination | stacking technique using a silicon penetration electrode.

  Next, the circuit board according to the present embodiment will be described.

Circuit board according to the present embodiment includes a first circuit member having a solder height t height t _m which is formed on the first projecting electrodes and said first protruding electrode on the _c, height t _s A second circuit member having a second projecting electrode, the first projecting electrode and the second projecting electrode are disposed to face each other, and the first projecting electrode and the second projecting electrode disposed to face each other. is interposed an adhesive layer having a thickness of t ₂ between the protrusion electrodes, by heating and pressing, the following formula (1), (2) and (3) placed opposite to satisfy the above first protruding electrode and the The second protruding electrode is electrically connected.
_{t 1 ≧ t c + t s} (1)
t ₁ × 1.3 ≧ t ₂ > t _c + t _m (2)
t ₁ × 1.3 ≧ t ₂ > t _c + t _s (3)
[Where t ₁ represents the distance along the stacking direction between the first circuit member and the second circuit member after heating and pressing, and t _c represents the height of the first protruding electrode. , T _s indicates the height of the second protruding electrode, t ₂ indicates the thickness of the adhesive layer before heating and pressing, and t _m indicates the height of the solder formed on the first protruding electrode. Show. ]

Here, the height t _c, t _m and t _s are all showing a height along the stacking direction of the first circuit member and second circuit member. Further, although the height t _m of the solder may vary before and after the heating and pressing, the height t _m in the formula (2) shows a solder height of heating before pressing.

  Hereinafter, as a preferred embodiment of the circuit board according to the present invention, a method of manufacturing a circuit board (hereinafter referred to as “semiconductor device”) using the adhesive sheet 10 for connecting circuit members will be described.

3 to 7 are schematic cross-sectional views for explaining a preferred embodiment of a method for manufacturing a semiconductor device according to the present invention. The manufacturing method of the semiconductor device of this embodiment is as follows:
(A) A semiconductor wafer (first circuit member) having a plurality of circuit electrodes (first projecting electrodes) on one main surface is prepared, and the present invention is provided on the side of the semiconductor wafer on which the circuit electrodes are provided. Providing an adhesive layer comprising the adhesive composition of
(B) a step of grinding the opposite side of the semiconductor wafer to the side where the circuit electrodes are provided to thin the semiconductor wafer;
(C) a step of dicing the thinned semiconductor wafer and the adhesive layer into individual semiconductor elements with a film adhesive;
(D) solder bonding the circuit electrode of the semiconductor element with a film adhesive to the circuit electrode (second protruding electrode) of the semiconductor element mounting support member (second circuit member);
Is provided.

  In the step (a) in this embodiment, the adhesive layer is provided by sticking the adhesive layer 2 of the adhesive sheet 10 to the side of the semiconductor wafer where the circuit electrodes are provided. In the step (d) in the present embodiment, the solder bonding is performed by heating, and the film adhesive interposed between the semiconductor element and the semiconductor element mounting support member is also cured. Hereinafter, each process will be described with reference to the drawings.

(A) Process First, the adhesive sheet 10 is arrange | positioned to a predetermined apparatus, and the protective film 1 is peeled off. Subsequently, a semiconductor wafer A having a plurality of circuit electrodes 20 on one of the main surfaces is prepared, the adhesive layer 2 is pasted on the side of the semiconductor wafer A on which the circuit electrodes are provided, and the support substrate 3 / adhesive layer 2 / A laminated body in which the semiconductor wafers A are laminated is obtained (see FIG. 3). The circuit electrode 20 is provided with bumps 21 coated with solder for soldering. Note that solder may be provided on the circuit electrode of the semiconductor element mounting support member.

  In the step (a), a commercially available film sticking apparatus or laminator can be used as a method for obtaining a laminate in which the support substrate 3 / adhesive layer 2 / semiconductor wafer A is laminated. In order to attach the adhesive layer 2 to the semiconductor wafer A without involving any voids, it is preferable that the attaching device is provided with a heating mechanism and a pressurizing mechanism, and more preferably a vacuum suction mechanism. Further, the shape of the adhesive sheet 10 may be a shape that can be worked by the sticking device, may be a roll shape or a sheet shape, and may be processed according to the outer shape of the semiconductor wafer A.

  The lamination of the semiconductor wafer A and the adhesive layer 2 is preferably performed at a temperature at which the adhesive layer 2 is softened, and the lamination temperature is preferably 40 to 80 ° C, more preferably 50 to 80 ° C, and 60 to 80 ° C. Further preferred. When laminating at a temperature lower than the temperature at which the adhesive layer 2 is softened, insufficient embedding of the semiconductor wafer A around the protruding circuit electrode 20 occurs, a void is involved, and the adhesive layer is peeled off during dicing. Deformation of the adhesive layer at the time of pickup, recognition mark identification failure at the time of alignment, and further reduction in connection reliability due to voids are likely to occur.

(B) Process Next, as shown in FIG. 4, the side opposite to the side where the circuit electrode 20 of the semiconductor wafer A is provided is ground by the grinder 4 to thin the semiconductor wafer. The thickness of the semiconductor wafer can be, for example, 10 to 300 μm. From the viewpoint of miniaturization and thinning of the semiconductor device, the thickness of the semiconductor wafer is preferably 20 to 100 μm.

  In the step (b), the semiconductor wafer A can be ground using a general back grind (B / G) apparatus. In order to uniformly grind the semiconductor wafer A without thickness unevenness in the B / G step, it is preferable that the adhesive layer 2 is evenly attached in the step (a) without involving voids.

(C) Process Next, as FIG. 5A shows, the dicing tape 5 is affixed on the semiconductor wafer A of a laminated body, this is arrange | positioned to a predetermined apparatus, and the support base material 3 is peeled off. At this time, when the support substrate 3 includes the pressure-sensitive adhesive layer 3a and the pressure-sensitive adhesive layer 3a is radiation curable, the pressure-sensitive adhesive layer 3a is cured by irradiating radiation from the support substrate 3 side. The adhesive force between the adhesive layer 2 and the support base 3 can be reduced. Here, examples of the radiation used include ultraviolet rays, electron beams, and infrared rays. Thereby, the support base material 3 can be easily peeled off. After the support substrate 3 is peeled off, the semiconductor wafer A and the adhesive layer 2 are diced by a dicing saw 6 as shown in FIG. Thus, the semiconductor wafer A is divided into a plurality of semiconductor elements A ′, and the adhesive layer 2 is divided into a plurality of film adhesives 2a.

  Next, as shown in FIG. 6, the dicing tape 5 was expanded (expanded), and the semiconductor elements A ′ obtained by the dicing were separated from each other and pushed up by the needle from the dicing tape 5 side. The semiconductor element 12 with a film adhesive comprising the semiconductor element A ′ and the film adhesive 2 a is sucked and picked up by the suction collet 7. The film-like adhesive-attached semiconductor element 12 may be collected by tray packing, or may be directly mounted on a circuit board with a flip chip bonder.

  In the step (c), the operation of attaching the dicing tape 5 to the ground semiconductor wafer A can be performed in the same step as the fixing to the dicing frame using a general wafer mounter. A commercially available dicing tape can be applied to the dicing tape 5, which may be a UV curable type or a pressure sensitive type.

(D) Step Next, as shown in FIG. 7, the circuit electrode 20 of the semiconductor element A ′ to which the film adhesive 2 a is attached and the circuit electrode 22 of the semiconductor element mounting support member 8 are aligned, The semiconductor element with film adhesive 12 and the semiconductor element mounting support member 8 are thermocompression bonded. By this thermocompression bonding, the circuit electrode 20 and the circuit electrode 22 are electrically and mechanically connected by solder bonding, and the film adhesive 2a is interposed between the semiconductor element A ′ and the semiconductor element mounting support member 8. A cured product is formed.

  The temperature during thermocompression bonding is preferably 200 ° C. or higher, and more preferably 220 to 260 ° C., from the viewpoint of solder bonding. The thermocompression bonding time can be 1 to 20 seconds. The pressure for thermocompression bonding can be 0.1 to 5 MPa.

  In mounting on a circuit board using a flip chip bonder, the alignment mark formed on the circuit surface of the semiconductor chip is confirmed through the adhesive layer 2a formed on the circuit surface of the semiconductor chip, and mounted on the circuit board. The position can be confirmed and implemented.

In FIG. 7, a corresponds to the height t _c of the first protruding electrode, b corresponds to the height t _m of the solder formed on the first protruding electrode, and c represents the second protrusion. corresponds to the height t _s of the electrodes, d corresponds to the distance t ₁ along the stacking direction between the first circuit member and second circuit member heating after pressurization. Here, a, b, c, the thickness _{t 2} of the d and the adhesive layer 10, the above formula (1), and thermocompression bonding so as to satisfy (2) and (3). By performing thermocompression bonding in this way, the solder spreads so as to cover the solder joint portion between the circuit electrode 20 and the circuit electrode 22 as shown in FIG. 7, and good connection reliability is obtained.

  The semiconductor device 30 is obtained through the above steps. The film-like adhesive made of the above adhesive composition has excellent embedding property and adhesive strength after curing, and also can remove the oxide film formed on the solder surface even in a short time of soldering. Can be improved. Therefore, the semiconductor device 30 is sufficiently resistant to reflow cracks in which generation of voids is sufficiently suppressed, the circuit electrodes are well soldered, and the semiconductor element A ′ and the semiconductor element mounting support member are bonded with sufficient adhesive force. And excellent connection reliability.

  The circuit board according to the present embodiment may use a circuit member having a highly densified circuit as a circuit member. For example, a circuit member including a silicon through electrode can be used.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples.

(Preparation of support substrate)
First, an acrylic copolymer was synthesized by a solution polymerization method using 2-ethylhexyl acrylate and methyl methacrylate as main monomers and hydroxyethyl acrylate and acrylic acid as functional group monomers. The resulting acrylic copolymer had a weight average molecular weight of 400,000 and a glass transition point of -38 ° C. A pressure-sensitive adhesive composition solution was prepared by blending 10 parts by mass of a polyfunctional isocyanate cross-linking agent (trade name “Coronate HL”, manufactured by Nippon Polyurethane Industry Co., Ltd.) with respect to 100 parts by mass of this acrylic copolymer.

  The obtained pressure-sensitive adhesive composition solution was applied onto a polyolefin film (trade name “WNH-2110”, manufactured by Okamoto Co., Ltd., thickness: 100 μm) so that the thickness of the pressure-sensitive adhesive layer when dried was 10 μm. , Dried. Further, a biaxially stretched polyester film (trade name “A3170, thickness: 25 μm” manufactured by Teijin DuPont Co., Ltd.) surface-treated with a silicone release agent was laminated on the surface of the pressure-sensitive adhesive layer. After standing for one week and sufficiently aging, the polyolefin film was peeled off and used as a supporting substrate.

[Example 1]
<Adjustment of adhesive composition>
“ZX1356-2” (trade name, manufactured by Tohto Kasei Co., Ltd., phenoxy resin) 25 parts by mass, “1032H60” (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), 20 parts by mass, “Epicoat 828” (Japan Epoxy Resin Co., Ltd.) Product name, liquid epoxy resin) 15 parts by mass and "HX3941HP" (Asahi Kasei Electronics Co., Ltd., product name, microcapsule type latent curing agent) 40 parts by mass were dissolved in a mixed solvent of toluene and ethyl acetate. To this solution, 10 parts by weight of “KW-4426” (trade name, core-shell type organic fine particles manufactured by Mitsubishi Rayon Co., Ltd.) and an average particle diameter of 1 μm cordierite particles (2MgO · 2Al ₂ O _3. “ADH” (product of Otsuka Chemical Co., Ltd.) subjected to classification treatment of 75 parts by mass and 5 μm, 5SiO ₂ , specific gravity 2.4, linear expansion coefficient: 1.5 × 10 ⁻⁶ / ° C., refractive index: 1.57 Name, adipic acid dihydrazide) 10 parts by mass was dispersed to obtain an adhesive varnish.

<Preparation of adhesive sheet for connecting circuit members>
The obtained adhesive varnish was applied onto a polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, trade name “AH-3”, thickness: 50 μm) using a roll coater, and 10 in an oven at 70 ° C. The film was dried for 30 minutes to form an adhesive layer having a thickness of 30 μm. Next, the adhesive layer and the pressure-sensitive adhesive layer surface of the support substrate were bonded together at room temperature to obtain an adhesive sheet for connecting circuit members.

<Fabrication of semiconductor device (circuit board)>
Using the adhesive sheet for circuit member connection obtained above, a semiconductor device was produced according to the following procedure.

(Attaching to semiconductor wafer)
On a suction stay heated to 80 ° C. of a die attach film mounter manufactured by JCM Co., Ltd., a 12 μm high copper bump (first protruding electrode) and a 13 μm high SnAg alloy (formed on the first protruding electrode) A semiconductor wafer (6 inches in diameter, thickness 725 μm, SnAg alloy is formed on a copper bump) on which a bump was formed was placed with the bump side facing up. The adhesive sheet for connecting circuit members is cut to 200 mm × 200 mm and the adhesive layer excluding the first film as the protective film is directed to the bump side of the semiconductor wafer, and die attach from the end of the semiconductor wafer so as not to entrain air. The laminate was pressed with the mounting roller of the mounter. After lamination, the protruding portion of the adhesive was cut along the outer shape of the wafer.

(Back grinding of the backside of the semiconductor wafer and peeling of the support substrate)
After the back surface of the semiconductor wafer is back-ground to a thickness of 150 μm with the back grinder manufactured by DISCO Corporation, the laminated body of the circuit sheet connecting adhesive sheet and the semiconductor wafer (thickness: 725 μm), and then back-ground semiconductor The wafer was placed on the suction stage of a die attach film mounter manufactured by JCM with the back grind side of the wafer facing up, and ADEKA dicing tape “AD80H” was attached at the same time as the dicing frame at room temperature. Next, a back grind tape peeling tape made by Nitto Denko was pasted on the supporting substrate, and only the supporting substrate was peeled off by peeling off 180 degrees.

(Dicing)
The semiconductor wafer with the adhesive layer fixed to the above-mentioned dicing frame was diced to 10 mm × 10 mm with a disco-made fully automatic dicing saw “DFD6361”. After dicing, washing, removing water, and UV irradiation from the dicing tape side, the separated semiconductor chip with adhesive was picked up.

(Crimping)
Place the semiconductor chip with adhesive on the glass-epoxy substrate with a circuit on which a copper terminal (second protruding electrode) with a height of 12 μm is formed at the position facing the bump, using the flip chip bonder “FCB3” manufactured by Matsushita Electric Industrial Co., Ltd. After combining, thermocompression bonding was performed at 250 ° C. and 0.5 MPa for 10 seconds to obtain a semiconductor device.

[Example 2]
A semiconductor device was obtained in the same manner as in Example 1 except that the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 26 μm.

[Example 3]
A semiconductor device was obtained in the same manner as in Example 1 except that the amount of cordierite particles in the adjustment of the adhesive composition was 100 parts by mass.

[Example 4]
Semiconductor device as in Example 1, except that the amount of cordierite particles in the adjustment of the adhesive composition was 100 parts by mass and the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 26 μm Got.

[Example 5]
A semiconductor device was obtained in the same manner as in Example 1 except that the amount of cordierite particles in the adjustment of the adhesive composition was 150 parts by mass.

[Example 6]
Semiconductor device as in Example 1, except that the amount of cordierite particles in the adjustment of the adhesive composition was 150 parts by mass and the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 26 μm Got.

[Comparative Example 1]
A semiconductor device was obtained in the same manner as in Example 1 except that the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 85 μm.

[Comparative Example 2]
A semiconductor device was obtained in the same manner as in Example 1 except that the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 20 μm.

[Comparative Example 3]
In the adjustment of the adhesive composition, “SRK-200” and cordierite particles were not blended, and the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 20 μm, in the same manner as in Example 1, A semiconductor device was obtained.

[Comparative Example 4]
Semiconductor device in the same manner as in Example 1 except that the amount of cordierite particles in the adjustment of the adhesive composition was 200 parts by mass, and the thickness of the adhesive layer in the production of the adhesive sheet for connecting circuit members was 20 μm. Got.

[Evaluation of adhesive layer]

(Measurement of linear expansion coefficient)
The adhesive sheets for connecting circuit members obtained in the examples and comparative examples were left in an oven set at 180 ° C. for 3 hours to perform heat curing treatment. The adhesive layer after heat curing was peeled off from the support substrate to prepare a test piece having a size of 30 mm × 2 mm. Using "TMA / SS6100" (trade name) manufactured by Seiko Instruments Inc., the above test piece is mounted in the apparatus so that the distance between chucks is 20 mm, measurement temperature range: 20 to 300 ° C, temperature increase rate: 5 ° C / min, load Conditions: Thermomechanical analysis was performed in the tensile test mode under the condition that the pressure was 0.5 MPa with respect to the cross-sectional area of the test piece, and the linear expansion coefficient was measured. After the measurement, the linear expansion difference between 100 ° C. and 40 ° C. was obtained, and the value divided by the temperature difference was calculated, and this was used as the average linear expansion coefficient for comparison.

(Reaction rate measurement)
2-10 mg of the adhesive layer in the adhesive sheet for connecting circuit members obtained in Examples and Comparative Examples was weighed into an aluminum measuring container, and DSC (Differential Scanning Calorimeter) “Pylis1” (trade name) manufactured by PerkinElmer Co. was used. The heating value was raised to 30 to 300 ° C. at a heating rate of 20 ° C./min, and the calorific value was measured. Next, the temperature was confirmed with a thermocouple that sandwiched the heating head of the thermocompression bonding apparatus, and the temperature reached 250 ° C. after 10 seconds. With this heating head setting, the adhesive sheet for connecting the circuit members was sandwiched between the separators and heated for 20 seconds to obtain an adhesive layer that had been subjected to the same heat treatment as in thermocompression bonding. The heat generation amount of the adhesive layer after the heat treatment was measured in the same manner, and this was used as the heat generation amount after the heating. Further, the calorific value was similarly measured for the adhesive layer after the adhesive sheet for circuit member connection was stored at room temperature (25 ° C.) for 14 days, and this was defined as the calorific value after storage. The reaction rate (%) was calculated from the obtained calorific value by the following formula.
Reaction rate (%) = (initial calorific value−calorific value after heating or calorific value after storage) / (initial calorific value) × 100

(Disc flow measurement)
The adhesive varnishes obtained in Examples and Comparative Examples were applied on a polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, trade name “AH-3”, thickness: 50 μm) using a roll coater, The film was dried in an oven at 70 ° C. for 10 minutes to form an adhesive layer having a thickness of 25 μm. Next, the adhesive layer and the pressure-sensitive adhesive layer surface of the support substrate were bonded together at room temperature to obtain an adhesive sheet for connecting circuit members. The obtained adhesive sheet for connecting circuit members was cut out to a size of 5 mm × 5 mm and attached to # 1737 glass (manufactured by Corning, thickness 0.5 μm) cut to a size of 15 mm × 15 mm, and the PET film was peeled off. Only the adhesive layer was left on the glass. A silicon chip (surface mirror treatment) having a thickness of 550 μm cut to 12 mm × 12 mm was superimposed on the adhesive layer on the glass, and the adhesive was sandwiched between the glass and the silicon chip. Using a thermocompression bonding machine having a heating tool set temperature of 197 ° C. set as a condition for reaching 180 ° C. after 20 seconds, heating and pressurization were performed for 20 seconds from the silicon chip side, and the adhesive layer was fluidized and cured. The adhesive area after flowing and curing was read by an image processing apparatus, and the flow amount of the adhesive with respect to the initial area was calculated. The flow amount was expressed as the ratio of the adhesive area after flowing to the initial area.

[Evaluation of semiconductor devices]
The embedding property and connection resistance of the film adhesive in the semiconductor devices manufactured in Examples and Comparative Examples were evaluated. Next, the produced semiconductor device was left to stand in a constant temperature and humidity chamber of 85 ° C. and 60% RH for 168 hours to absorb moisture, and exposed to a reflow furnace set at 260 ° C. three times. After the exposure, the connection resistance and the interface state of the connection part were confirmed. Moreover, the temperature cycle test was done about the semiconductor device after reflow. The evaluation results are shown in Tables 1 and 2.

<Embedment after crimping>
The adhesion state of the adhesive layer was observed with an ultrasonic flaw detector (SAT) manufactured by Hitachi Construction Machinery and evaluated based on the following criteria.
○: No peeling or void is observed.
Δ: No peeling is observed. There are no voids in the center of the chip, and minute voids are observed in the vicinity of the outer periphery of the chip.
X: Peeling and voids are observed on the entire surface of the chip.

<Connectivity after reflow>
The connection state after reflow of the adhesive layer was observed with an ultrasonic flaw detector (SAT) manufactured by Hitachi Construction Machinery, and evaluated based on the following criteria.
○: No peeling is observed.
X: Peeling is observed.

<Connection resistance>
About the produced semiconductor device, the connection resistance after pressure bonding and the connection resistance after reflow were measured using a digital multimeter (manufactured by Advantest Co., Ltd., product name) and evaluated based on the following criteria.
○: Connection resistance at all terminal connections of the mounting TEG applied to the test is obtained.
X: A disconnection defective terminal exists.

<Temperature cycle test>
The semiconductor device after the reflow was put into a temperature cycle test in which one cycle was −55 ° C. for 30 minutes and 125 ° C. for 30 minutes, and it was evaluated whether or not the connection resistance in the test machine was maintained. Tables 1 and 2 show the number of cycles that could be energized.

  As shown in Table 1, the semiconductor devices obtained in Examples 1 to 6 did not generate voids, showed good connectivity even after reflow, and were able to conduct for 1000 cycles or more in the temperature cycle test. On the other hand, in the semiconductor devices obtained in Comparative Examples 1 to 4, many voids were observed, connectivity after reflow deteriorated, connection failure occurred in 100 cycles of the temperature cycle test, and solder wettability. It was confirmed that the soldering was insufficient and the connection reliability was inferior due to insufficient soldering.

  DESCRIPTION OF SYMBOLS 1 ... Protective film, 2 ... Adhesive layer, 3 ... Support base material, 3a ... Adhesive layer, 3b ... Plastic film, 4 ... Grinder, 5 ... Dicing tape, 6 ... Dicing saw, 7 ... Suction collet, 8 ... Semiconductor Element mounting support member, 10... Circuit member connection adhesive sheet, 11. Circuit member connection adhesive sheet, 12... Semiconductor element with film adhesive, 20... Circuit electrode, 21. Solder bump, 30. A: Semiconductor wafer.

Claims (8)

A first circuit member having a first protruding electrode having a height t _c and a solder having a height t _m formed on the first protruding electrode;
Second and a circuit member having a second protruding electrode height t _s,
The first protruding electrode and the second protruding electrode are arranged to face each other,
Is interposed an adhesive layer having a thickness of t ₂ between the opposite disposed first protruding electrode and the second protruding electrode, hot pressed, the following formula (1), (2) and (3) A circuit board formed by electrically connecting the first projecting electrode and the second projecting electrode, which are disposed so as to face each other.
_{t 1 ≧ t c + t s} (1)
t ₁ × 1.3 ≧ t ₂ > t _c + t _m (2)
t ₁ × 1.3 ≧ t ₂ > t _c + t _s (3)
[Where t ₁ represents the distance along the stacking direction between the first circuit member and the second circuit member after heating and pressing, and t _c represents the height of the first protruding electrode. , T _s indicates the height of the second protruding electrode, t ₂ indicates the thickness of the adhesive layer before heating and pressing, and t _m indicates the height of the solder formed on the first protruding electrode. Show. ]   The adhesive layer comprises (A) a thermoplastic resin, (B) a thermosetting resin, (C) a latent curing agent, (D) an inorganic filler, (E) organic fine particles, and (F) room temperature. The circuit board according to claim 1, wherein the circuit board is an adhesive layer comprising an adhesive composition comprising a solid and a powder compound having a maximum particle size of 20 μm or less.   The circuit board according to claim 2, wherein the component (F) is at least one compound selected from a compound having a carboxyl group, a compound having a methylol group, and a hydrazide compound.   The circuit board according to claim 2, wherein the component (B) contains an epoxy resin. A first circuit member having a first protruding electrode having a height t _c and a solder having a height t _m formed on the first protruding electrode;
Second and a circuit member having a second protruding electrode height t _s,
The first protruding electrode and the second protruding electrode are arranged to face each other,
Is interposed an adhesive layer having a thickness of t ₂ between the opposite disposed first protruding electrode and the second protruding electrode, hot pressed, the following formula (1), (2) and (3) A method for manufacturing a circuit board, comprising electrically connecting the first protruding electrode and the second protruding electrode, which are arranged to face each other.
_{t 1 ≧ t c + t s} (1)
t ₁ × 1.3 ≧ t ₂ > t _c + t _m (2)
t ₁ × 1.3 ≧ t ₂ > t _c + t _s (3)
[Where t ₁ represents the distance along the stacking direction between the first circuit member and the second circuit member after heating and pressing, and t _c represents the height of the first protruding electrode. , T _s indicates the height of the second protruding electrode, t ₂ indicates the thickness of the adhesive layer before heating and pressing, and t _m indicates the height of the solder formed on the first protruding electrode. Show. ]   The adhesive layer comprises (A) a thermoplastic resin, (B) a thermosetting resin, (C) a latent curing agent, (D) an inorganic filler, (E) organic fine particles, and (F) room temperature. The method for producing a circuit board according to claim 5, wherein the adhesive layer comprises an adhesive composition comprising a powder compound having a maximum particle size of 20 μm or less.   The method for producing a circuit board according to claim 6, wherein the component (F) is at least one compound selected from a compound having a carboxyl group, a compound having a methylol group, and a hydrazide compound.   The method for manufacturing a circuit board according to claim 6 or 7, wherein the component (B) contains an epoxy resin.

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