JP3835583B2 - Electronic component equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic component device obtained by bonding and fixing a semiconductor chip to a substrate with an anisotropic conductive adhesive film by, for example, a face-down method and electrically connecting both electrodes.
[0002]
[Prior art]
An anisotropic conductive adhesive film is made of an adhesive containing a predetermined amount of conductive particles such as metal particles. This anisotropic conductive adhesive film is provided between an electronic component and an electrode or circuit and is pressurized or heated. By constructing the pressure means, both electrodes are electrically connected to each other, and insulation between adjacent electrodes is imparted so that the electronic component and the circuit are bonded and fixed.
The basic idea for improving the connection reliability of anisotropic conductive adhesive films is to ensure the insulation between adjacent electrodes by making the particle size of the conductive particles smaller than the space between adjacent electrodes. In other words, the electrical connection in the connection portion is obtained by making the content of the conductive particles not to contact the conductive particles and reliably present on the electrodes.
[0003]
[Problems to be solved by the invention]
In the present invention, for example, circuit members having connection terminals are connected to each other, such as a circuit board obtained by bonding and fixing a semiconductor chip to a substrate with an anisotropic conductive adhesive film or the like and electrically connecting both electrodes. The present invention provides an electronic component device connected with excellent connection reliability.
[0004]
[Means for Solving the Problems]
The electronic component device of the present invention includes an electronic component having a first connection terminal, and a mounting substrate having a second connection terminal formed on the surface of the insulating substrate, the first connection terminal and the second connection. An anisotropic conductive adhesive having an elastic modulus at 40 ° C. after connection of 100 to 1500 MPa between the first connection terminal and the second connection terminal that are arranged to face each other. An electronic component device in which the first connection terminal and the second connection terminal, which are disposed and pressed to be opposed to each other, are electrically connected to each other, and the insulating layer of the mounting substrate on which the second connection terminal is formed An insulating layer of a resin film having an elastic modulus at 150 ° C. of 1 to 500 MPa and containing no glass cloth is formed on the surface of the insulating substrate that is the outermost layer, and is disposed opposite to the first connection terminal. The second connection terminal that is pressed and electrically connected is The displacement is characterized in that a 10 to 50 [mu] m. On the insulating substrate surface of the mounting substrate on which the second connection terminal is formed, an insulating material layer having an elastic modulus at 150 ° C. of 1 to 500 MPa, and further an elastic modulus at 150 ° C. of 1 to 500 MPa and 25 ° C. It is preferable that an insulating material layer having an elastic modulus of 50 to 3500 MPa is formed. An anisotropic conductive adhesive is used as the adhesive, and a semiconductor chip is preferable as the electronic component.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, active components such as semiconductor chips, transistors, diodes, and thyristors, chip components such as passive devices such as capacitors, resistors, and coils, and substrates such as printed boards are used as electronic components.
By heating and pressurizing the electronic component to the mounting substrate, the connection terminals arranged opposite to each other are electrically connected by direct contact or through conductive particles of an anisotropic conductive adhesive.
[0006]
The mounting substrate in the present invention can also use a resin film that does not contain glass cloth in the insulating layer that is the outermost layer of the insulating layer.
As this resin film, an epoxy resin, a polyimide resin, a polyamideimide resin, a modified polyphenylene ether resin, a phenoxy resin, an amide epoxy resin, a phenol resin, a mixture thereof, a copolymer, or the like can be used. In addition, films of heat-resistant thermoplastic engineering plastics such as polysulfone, polyethersulfone, polyetheretherketone, wholly aromatic liquid crystal polyester, and fluorine resin can be used.
A resin film containing an organic or inorganic filler can be used.
[0007]
As the adhesive used in the present invention, a film or a liquid can be used. However, the film is not formed on the substrate by a coating or printing method like a liquid, but is simply disposed and used in the bonding process. In addition to being easy to handle and easy to handle, the film thickness is easily controlled in consideration of the height of the connection terminal, which is preferable. The adhesive is preferably a thermoplastic polymer or a cross-linked polymer that is cured by energy such as heat, electron beam, or light, and among them, an epoxy resin, a cyanate ester resin, and an imide resin are preferable. Moreover, a thermoplastic polymer can be mixed for the purpose of imparting flexibility and film-forming properties to these resins. Adhesion is performed by pressurization and heating. Therefore, if the melt viscosity of the adhesive at the time of heating is too high, the adhesive is not excluded, and electrical conduction cannot be ensured. Therefore, the melt viscosity at the adhesive heating temperature of the adhesive is 1000 It is preferable to make it below the poise.
[0008]
The adhesive in the present invention preferably has an elastic modulus at 40 ° C. after bonding of 100 to 4000 MPa, and particularly preferably 100 to 1500 MPa for the purpose of relieving stress based on the difference in thermal expansion coefficient between the chip and the substrate. For example, as an adhesive, a mixture of an epoxy resin and a latent curing agent such as imidazole, hydrazide, boron trifluoride-amine complex, sulfonium salt, amine imide, polyamine salt, dicyandiamide, etc. at 40 ° C. after bonding. The adhesive which mix | blended acrylic rubber so that an elasticity modulus may be set to 100-1500 Mpa is mention | raise | lifted. The elastic modulus of the cured adhesive film can be measured by using, for example, Rheospectra DVE-4 manufactured by Rheology Co., Ltd. (pull mode, temperature rising at 10 Hz, 5 ° C./min).
[0009]
Examples of the acrylic rubber used in the present invention include a polymer or copolymer having at least one of acrylic acid, acrylic acid ester, methacrylic acid ester or acrylonitrile as a monomer component. Among them, glycidyl acrylate containing a glycidyl ether group, A copolymer acrylic rubber containing glycidyl methacrylate is preferably used. The molecular weight of these acrylic rubbers is preferably 200,000 or more from the viewpoint of increasing the cohesive strength of the adhesive. If the blending amount of acrylic rubber in the adhesive is 15 wt% or less, the elastic modulus at 40 ° C. after bonding exceeds 1500 MPa, and if it exceeds 40 wt%, the elastic modulus can be reduced, but melting at the time of connection Since the viscosity increases and the exclusion of the molten adhesive between the connection electrode boundaries or at the interface between the connection electrode and the conductive particles is reduced, it becomes impossible to ensure electrical continuity between the connection electrodes or between the connection electrodes and the conductive particles. For this reason, as an acrylic compounding quantity, 15-40 wt% is preferable. Since these acrylic rubbers blended in the adhesive have a peak temperature of dielectric loss tangent due to the rubber component in the vicinity of 40 to 60 ° C., the elastic modulus of the adhesive can be reduced.
[0010]
In the adhesive used in the present invention, conductive particles can be dispersed for the purpose of positively imparting anisotropic conductivity in order to absorb variations in the height of the bumps of the chip and the circuit electrodes. In the present invention, the conductive particles are, for example, metal particles such as Au, Ni, Ag, Cu, W and solder or metal particles formed by plating or vapor deposition of a thin film such as gold or palladium on the surface of these metal particles, such as polystyrene. Conductive particles in which a polymer spherical core material is provided with a conductive layer such as Ni, Cu, Au, or solder can be used.
[0011]
The particle size needs to be smaller than the minimum distance between the electrodes of the substrate, and when there is a variation in the height of the electrodes, it is preferably larger than the variation in height, and preferably 1 μm to 10 μm. The amount of conductive particles dispersed in the adhesive is 0.1 to 30% by volume, preferably 0.2 to 15% by volume.
[0012]
The connection electrodes of the semiconductor chip in the present invention are plated bumps that are plated with gold, nickel, solder, etc., and the tips of metal wires such as gold, aluminum are formed into a ball shape by heat energy. Ball bumps, solder balls, molten solder formed bumps, and bump electrodes formed by soldering a column, which are bump electrodes formed by cutting the metal wire after being crimped onto the electrode pads of the semiconductor chip, can be used.
[0013]
【Example】
Example A chip (10 mm × 10 mm, thickness: 0.5 mm) with wire bumps (diameter: 50 μmΦ, space 30 μm, height: 30 μm, number of bumps 288) produced from a gold wire was used as a semiconductor chip.
The surface copper foil of MCL-E-679 (trade name, manufactured by Hitachi Chemical Co., Ltd.), which is a glass cloth / epoxy resin double-sided copper-clad laminate, is subjected to inner layer circuit processing and inner layer adhesion treatment by the existing subtract method.
Next, a copper-bonded epoxy adhesive film MCF-3000E (trade name, manufactured by Hitachi Chemical Co., Ltd.) that does not have a glass cloth that has been previously drilled on the inner layer circuit surface is 170 ° C., 40 kgf / cm. ^{2. For} 60 minutes, press lamination bonding was performed, through-hole drilling, electroless copper plating, outer layer circuit processing by subtracting method and electroless nickel / gold plating were performed to obtain a mounting substrate.
An anisotropic conductive film (thickness: 50 microns) made of an epoxy-based adhesive film in which nickel particles (diameter: 5 μm) are dispersed at 2 vol% is affixed to a mounting substrate at 80 ° C. and 10 kgf / cm ^2. The mounting substrate (thickness: 0.8 mm) was aligned. Next, the main connection was performed by heating and pressing from above the chip under the conditions of 180 ° C., 30 g / bump, and 20 seconds. After this connection, the electrodes of the mounting substrate electrically connected to the bumps of the semiconductor chip were embedded in an insulating layer of 15 to 20 microns compared to before connection. The connection resistance after this connection is a maximum of 6 mΩ per bump, an average of 2 mΩ, and an insulation resistance of 10 ⁸ Ω or more. These values are from the thermal shock test at −55 to 125 ° C. for 1000 cycles, the PCT test (121 No change even after 10 seconds of immersion in a solder bath at 260 ° C. for 200 hours at 2 ° C., and good connection reliability was exhibited.
[0014]
【The invention's effect】
According to the present invention, an electronic component device such as a semiconductor device having excellent connection reliability between an electronic component such as a semiconductor chip and a mounting substrate can be obtained.
According to the present invention, since the electrodes of the mounting substrate are buried in the substrate after connection, it is possible to absorb variations in bumps of the semiconductor chip and mounting substrate electrodes, and to reduce stress based on the difference in thermal expansion coefficient between the chip and the mounting substrate. Because it can be mitigated by the surface layer of the mounting board, there is no increase in connection resistance or peeling of the adhesive even after reliability tests such as thermal shock, PCT or solder bath immersion test, and the connection reliability of the circuit board is greatly increased To improve.

Claims (1)

An electronic component having a first connection terminal;
A mounting substrate having a second connection terminal formed on the surface of the insulating substrate;
The first connection terminal and the second connection terminal are arranged to face each other,
An anisotropic conductive adhesive having an elastic modulus at 40 ° C. of 100 to 1500 MPa after connection is interposed between the first connection terminal and the second connection terminal that are arranged to face each other, and is pressed against the opposite. An electronic component device in which the arranged first connection terminal and second connection terminal are electrically connected,
The insulating substrate surface that is the outermost layer of the insulating layer of the mounting substrate on which the second connection terminals are formed has an elastic modulus at 150 ° C. of 1 to 500 MPa and an insulating material for a resin film that does not include glass cloth in the insulating layer The second connection terminal formed with a layer and opposed to the first connection terminal and pressed and electrically connected has a displacement of 10 to 50 μm compared to that before connection. Parts device.