JPH0640558B2 - Electronic component device - Google Patents

Description

The present invention relates to an electronic component device, and more particularly to an electronic component device suitable for mounting on a low heat resistant structure.

[Prior Art] Conventionally, a wire bonding method using a fine wire such as Au or Al is generally used for mounting electronic components of this type (hereinafter, IC mounting will be described as an example). Although it has general versatility, such as thermocompression bonding of Au thin wires and thermocompression bonding using ultrasonic waves, it is necessary to heat the substrate to about 150 ° C to 350 ° C, and it is necessary to apply it to a low heat resistant structure such as a liquid crystal element. It was not suitable for IC mounting.
Further, the wire bonding method has a high wiring defect rate when a large number of wiring lines are formed, takes a lot of time for wiring work, is troublesome to correct and repair, has a coarse wiring pitch, and is not suitable for high-density mounting. There is a defect that thin mounting is impossible due to the protective sealant.

Gang carrier bonding methods such as film carrier bonding and flip chip bonding are available as solutions to these problems, but these methods solve many of the drawbacks of the wire bonding method, but on the other hand, a barrier metal is used for the extraction electrode on the IC chip. However, since it is necessary to perform a special treatment on the bump metal or the like, there is a drawback that the versatility is poor such that the cost of the IC chip is high and it is difficult to obtain the IC chip.
In addition, the film carrier bonding method has a drawback that the cost is increased because a film made of polyimide or the like in which copper foil or the like is patterned is used. In the flip chip bonding method, 5Sn-95Pb is used for the bump electrode.
However, there is a drawback in that the temperature at the time of joining becomes high because the above solder is used.

Among the shortcomings of wire bonding method and gang bonding method, low temperature process, improvement of easiness of replacement of defective chip and mounting of IC chip on liquid crystal panel glass substrate via rubber connector with conductors selectively arranged A method of connecting a circuit board and an IC chip is known.

[Problems to be Solved by the Invention] However, in the above-mentioned method, a special treatment such as bump metal is required for the extraction electrode on the IC chip, and a rubber connector in which conductors are arranged is used.
Since the rubber connector and the IC chip need to be aligned with each other, the workability is poor, and since they are fixed with a retainer having a spring property after the alignment, the structure is complicated and the cost is increased.

[Means for Solving the Problems] The above-mentioned problems are caused by the above-mentioned problems in that the circuit board having the thick film conductor having the convex portion on the surface formed on the insulating substrate and the electronic component arranged on the circuit board are The problem is solved by the electronic component device of the present invention, in which the projections of the thick film conductor and the extraction electrodes of the electronic component are aligned with each other and are electrically connected through the anisotropic conductive adhesive layer.

EXAMPLES Examples of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an IC showing an embodiment of the electronic component device of the present invention.
In the cross-sectional view of the device, reference numeral 1 is a circuit board in which a first thick film conductor 3 and a second thick film conductor 4 are formed on an insulating substrate 2 such as glass or ceramic. As a thick film conductor, Au, Au-
A noble metal-based material such as Pd or Ag-Pd or a material such as Cu or Ni-based material is used, but the first thick film conductor 3 and the second thick film conductor 4 are used.
May be the same material, the same kind of material, or a combination of different kinds of materials. 5 is an anisotropic conductive adhesive layer, and insulating resin 6
Conductors 7 made of Au, Ag, Cu, Ni, C, etc. are dispersed therein, and 8 is an electronic component such as an IC chip, a resistor and a capacitor, which is an IC chip here. 9 is an IC chip 8
It is an extraction electrode formed on the top. In order to make the circuit board 1, first, a paste for forming the first thick film conductor is supplied on almost the entire surface of the insulating substrate 2 by a method such as printing, spin coating, leveling, drying and firing. Next, the paste for forming the second thick film conductor is supplied to a desired position by a method such as printing or spin coating, leveled, dried and baked. First
The firing of the paste for forming the second thick film conductor can also be performed at the same time. Further, a photoresist is applied on the above-mentioned baked paste, exposed and developed, and then the paste is etched using the photoresist as a mask to form the first and second thick film conductors. At this time, the second thick film conductor is formed in a projecting shape or a convex shape at the same pitch as the extraction electrodes 9 of the IC chip 8. It is also possible to directly form a pattern for the thick film conductor by a printing method instead of the photo process as described above.

Next, the connection method will be described.

On the circuit board 1, a conductive adhesive that exhibits an anisotropic conductivity after curing (conductive powder such as metal powder is dispersed in the insulating resin adhesive as described above) is printed at a desired position. The IC chip 8 was mounted on the circuit board 1 by substantially aligning the positions of the second thick film conductor 4 formed on the circuit board 1 in a protruding shape or the convex shape with the extraction electrode 9 formed on the IC chip 8. When pressure is applied from the side of the rear IC chip 8 while heating with a heater (not shown), the insulating resin 6 is heat-fused and fixed between the circuit board 1 and the IC chip 8 and the second protrusions or protrusions are formed.
The portion pressed by the thick film conductor 4 comes into contact with the extraction electrode 9 of the IC chip 8 through the conductor 7 and is electrically conducted. The fixing of the IC chip 8 is not limited to the insulating resin 6, but an adhesive for reinforcement may be used or a metal fitting may be attached. Further, it is naturally possible to cover the entire IC chip 8 with another insulating resin while also strengthening the sealing of the IC chip 8. In the above description of the connecting method, the case where a liquid conductive adhesive is used as a method for producing an anisotropic conductive adhesive is shown. However, in addition, for example, a solid adhesive having an insulating property such as a metal powder having a conductive property is used. You may use the solid adhesive which disperse | distributed powder and shape | molded in the shape of a sheet.

FIG. 2 is a cross-sectional view showing an embodiment of the IC device in which an IC chip is mounted on a liquid crystal display panel glass substrate, 10 is a lower substrate, 11 is an upper substrate, 12 is a liquid crystal, 1
Reference numeral 3 is a sealant, and the first and second thick film conductors 3 and 4 are formed on the lower substrate 10 by the above-described manufacturing method. More preferably, the first thick film conductor 3 includes the sealant 13. It is formed up to a substantially intermediate position to be applied and is connected to the thin film conductor 14 made of ITO, Al or the like for driving the liquid crystal. First thick film conductor 3
It is possible to omit the protection of the thin film conductor 14 by forming the sealing agent 13 up to the position of the sealing agent 13.

The IC chip 8 is connected and sealed to the lower substrate 10 by the same method as the above-mentioned connecting method, but the IC chip 8 can be mounted without heating the liquid crystal 12 so that the lower substrate 1 can be mounted.
The number of extraction electrodes (not shown) for driving the liquid crystal from 0 can be significantly reduced.

Example 0.6 μm Au paste on a glass substrate (# 7059 manufactured by Corning, width 10 mm x length 20 mm x thickness 1.1 mm)
The wiring pattern was formed with a thickness of 10 μm, and the protruding electrode was formed with a thickness of 10 μm of Au paste on a part of the wiring pattern. Projection electrodes are 200 μm pitch, width 100 μ
It was formed in a shape of m × 200 μm in length and 4 mm in width × 10 mm in length. 2 on the glass substrate, an anisotropic conductive adhesive paste (Morfit HM-2000 manufactured by Osaka Soda).
Printed to a thickness of 0 μm and mounted with a silicon substrate, 150 ° C, 1
It was heated and pressed under the conditions of 0 kg / cm ² and 15 seconds for heat fusion. The silicon substrate had a test conductor pattern and lead electrodes formed of Al, and the lead electrodes had a 200 μm pitch, a width of 120 μm × a length of 250 μm, and outer dimensions of 4 mm × 10 mm. The connection resistance (contact resistance) between the glass substrate and the silicon substrate via the anisotropic conductive adhesive paste was a value of 20Ω to 50Ω, and was 40Ω on average. It has been confirmed that the connection resistance has no problem in mounting a voltage drive type IC, for example, a liquid crystal drive IC.

It should be noted that, assuming that a defective connection such as a defective IC chip or a circuit board or a defective alignment at the time of connection was found after the completion of mounting, carbitol acetate solvent was used to repeatedly connect and separate, but several times. It was confirmed that there was no problem in the number of times of repeating and the actual mounting structure was excellent in repairability.

[Effects of the Invention] As described in detail above, according to the electronic component device of the present invention, the following effects can be obtained.

(1) Since it is a low temperature connection process, there are no restrictions on parts, materials, configurations, etc.

(2) Repair is possible.

(3) Since it is a batch bonding method, it can be connected in a short time even if the number of connection pins is large, and it has excellent productivity because it has a structure that also serves as sealing.

(4) Thin and high-density mounting is possible.

The electronic component device of the present invention enables IC mounting especially on a low heat resistant structure such as a liquid crystal display panel, and its practical effects are great.

[Brief description of drawings]

FIG. 1 is an IC showing an embodiment of the electronic component device of the present invention.
It is sectional drawing of an apparatus. FIG. 2 is a sectional view showing an embodiment of the IC device. 1, 10 ... circuit board 3 ... first thick film conductor 4 ... second thick film conductor 5 ... anisotropic conductive adhesive layer 6 ... insulating resin 7 ... conductor 8 ... IC chip 9 ...... Ejection electrode

Claims (4)

[Claims] 1. A circuit board having a thick film conductor having a convex portion on a surface formed on an insulating substrate, and an electronic component arranged on the circuit board, wherein the convex portion of the thick film conductor and the electronic component An electronic component device characterized in that it is aligned with a lead-out electrode and is electrically connected through an anisotropic conductive adhesive layer. 2. The electronic component device according to claim 1, wherein the thick film conductor is provided in the vicinity of the seal portion of the liquid crystal driving glass substrate, and the thick film conductor is connected to the liquid crystal driving thin film conductor. 3. The thick film conductor includes a first thick film conductor formed on the insulating substrate and a second thick film conductor formed in a convex shape on the thick film conductor.
The electronic component device according to claim 1, wherein the electronic component device is formed of the thick film conductor according to claim 1. 4. The electronic component device according to claim 3, wherein the first and second thick film conductors are made of the same material.