JP2011017011A - Method of temporal pressure bonding of anisotropic conductive adhesive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of temporal pressure bonding of an anisotropic conductive adhesive film to a circuit member, which method suppresses foaming.SOLUTION: In the method of temporal pressure bonding of an anisotropic conductive adhesive film, an anisotropic conductive adhesive film 1 is temporally pressure bonded to a circuit member 2 while being applied with ultrasonic waves or microwaves.

Description

  The present invention relates to a method for temporarily pressing an anisotropic conductive adhesive film to a circuit member.

A technique for connecting a semiconductor element to a substrate using an anisotropic conductive adhesive film has been widely used in recent years because a connection of a narrow pitch electrode can be easily obtained only by applying heat and pressure. In particular, the connection of the driving LSI to the liquid crystal panel in the liquid crystal display device is a method of thermocompression-bonding the tape carrier to which the LSI is bonded using an anisotropic conductive adhesive film to connect between different materials such as transparent electrodes and metal Is common. In addition, as a method for mounting a liquid crystal driving IC on a liquid crystal display glass panel, a COG (Chip On Glass) mounting method in which the liquid crystal driving IC is directly bonded to the glass panel with a thermosetting adhesive is used.
Next, a conventional method for connecting a liquid crystal panel and a driving LSI will be described. The drive LSI uses a so-called tape carrier package (hereinafter abbreviated as TCP) in which a semiconductor chip is bonded to a copper foil lead formed on a film tape such as polyimide. As shown in FIG. 3A, an anisotropic conductive adhesive film 22 is temporarily pressure-bonded onto the terminal 21 of the liquid crystal panel 20. After that, as shown in FIG. 3B, the TCP 23 terminal and the liquid crystal panel terminal are aligned and temporarily fixed using the adhesive property of the anisotropic conductive adhesive film 22.
Next, the liquid crystal panel 20 is placed on the stage, and the terminal of the TCP 23 is pressed with a high-temperature pressurizing device to apply pressure and heat to the anisotropic conductive adhesive film 22, thereby providing the anisotropic conductive adhesive film 22. The adhesive is cured in a state where the conductive particles inside are sandwiched between both electrodes of the liquid crystal panel 20 and the TCP 23 to obtain mechanical and electrical connection (not shown).

However, at the time of the temporary pressure bonding shown in FIG. 3A, it is inevitable that large bubbles exist between the anisotropic conductive adhesive film and the liquid crystal panel as shown in FIG. When such bubbles exist, there is a problem that condensation occurs in the gap due to a temperature change and migration (electric corrosion) occurs.
An object of the present invention is to provide a method for temporarily pressing an anisotropic conductive adhesive film that suppresses the generation of bubbles.

According to the present invention, the following method for temporarily pressing an anisotropic conductive adhesive film is provided.
1. A method for temporary pressure bonding of an anisotropic conductive adhesive film, characterized in that the anisotropic conductive adhesive film is temporarily bonded to a circuit member using a laminator.
2. A method for temporarily pressing an anisotropic conductive adhesive film, wherein the anisotropic conductive adhesive film is temporarily bonded to a circuit member while applying ultrasonic waves or microwaves.
3. A method for temporarily crimping an anisotropic conductive adhesive film, wherein the anisotropic conductive adhesive film is temporarily crimped to a circuit member while a temporary crimping portion of the circuit member is evacuated.
4). 4. The total area of bubbles formed between the anisotropic conductive adhesive film and the circuit member is 5% or less of the contact area between the anisotropic conductive adhesive film and the circuit member, Temporary pressure bonding method of anisotropic conductive adhesive film.

  ADVANTAGE OF THE INVENTION According to this invention, the temporary crimping | compression-bonding method of the anisotropically conductive adhesive film which suppresses bubble generation can be provided.

It is a figure which shows the temporary crimping | compression-bonding method of the anisotropically conductive adhesive film which is one Embodiment concerning this invention. It is a figure which shows the temporary crimping | compression-bonding method of the anisotropically conductive adhesive film which is other embodiment concerning this invention, (a) is sectional drawing which shows position alignment of each member, (b) applies an ultrasonic wave. It is sectional drawing which shows pressurizing. (A) is a perspective view which shows the temporary crimping | compression-bonding of the anisotropic conductive adhesive film to a liquid crystal panel, (b) is a perspective view which shows temporary fixation of the liquid crystal panel and a semiconductor element through an anisotropic conductive adhesive film. is there. It is sectional drawing which shows the temporary crimping | compression-bonding of the anisotropically conductive adhesive film to the conventional liquid crystal panel.

Embodiment 1
FIG. 1 is a diagram showing a method for temporarily pressing an anisotropic conductive adhesive film according to an embodiment of the present invention.
In this embodiment, the anisotropic conductive adhesive film 1 is temporarily pressure-bonded to the glass substrate 2 using a laminator 10. A normal laminator 10 can be used.
First, the anisotropic conductive adhesive film 1 is drawn out from the take-up roll 3 and conveyed. The continuous anisotropic conductive adhesive film 1 is sent out to the pressure roller 11 of the laminator 10. On the other hand, the glass substrate 2 is conveyed to the pressure roller 11 in the arrow direction. The anisotropic conductive adhesive film 1 and the glass substrate 2 are introduced between the upper and lower pressure rollers 11 in a state where the anisotropic conductive adhesive film 1 and the glass substrate 2 are positioned by a sensor (not shown) or the like. . The anisotropic conductive adhesive film 1 is temporarily pressure-bonded to the glass substrate 2 by the pressure roller 11 and sent out. The anisotropic conductive adhesive film 1 is cut at a necessary site by a cutter 12 of a laminator 10.
Also, when the anisotropic conductive adhesive film 1 is transported to the pressure roller 11 while peeling the release paper (not shown), an adhesive tape or the like is provided in the middle of an appropriate transport path to lift the release paper. May be.
In the present embodiment, since the anisotropic conductive adhesive film 1 is temporarily pressure-bonded to the glass substrate 2 from the end by the pressure roller 11, bubbles are hardly generated, and even if they are generated, they are pushed out. Accordingly, generation of large bubbles at the adhesion site can be prevented.

Embodiment 2
FIG. 2 is a view showing a method for temporarily pressing an anisotropic conductive adhesive film according to another embodiment of the present invention.
In this embodiment, the anisotropic conductive adhesive film is temporarily bonded to the circuit member while applying ultrasonic waves.
In order to perform temporary pressure bonding while applying ultrasonic waves, first, the circuit member 2 is placed on the work plate 4 as shown in FIG. 2A, and the anisotropic conductive adhesive film 1 is placed thereon. It is preferable to use an apparatus 30 that can perform ultrasonic vibration and heating and pressurization together, which is a commercially available product, such as SH50MP (manufactured by Artex Co., Ltd.). As shown in FIG. 2B, using this apparatus 30, pressure is applied from above the anisotropic conductive adhesive film 1, and ultrasonic waves are applied in a direction perpendicular to the pressure direction. Large bubbles are unlikely to form when bonded while applying ultrasonic waves.
As for the conditions at the time of connection, the heating and pressing time is preferably 1 to 5 seconds, more preferably 2 to 3 seconds. If the heating and pressing time is less than 1 second, the generation of bubbles may not be sufficiently suppressed, and if it exceeds 5 seconds, the productivity may be inferior.
The heating temperature is preferably 40 to 80 ° C. When the heating temperature is less than 40 ° C, good temporary pressure bonding may be difficult, and when it exceeds 80 ° C, the adhesive film is cured, and it is difficult to obtain good circuit connection at the time of subsequent main pressure bonding There is.
The pressure is preferably 0.3 to 2.0 MPa, more preferably 0.5 to 1.5 MPa. When the pressure is less than 0.3 MPa, the generation of bubbles may not be sufficiently suppressed, and when the pressure exceeds 2.0 MPa, the electrode of the circuit member may be destroyed.
The frequency of the ultrasonic wave is preferably 10 to 50 kHz. The application time of ultrasonic waves is preferably 1 to 5 seconds, and more preferably 2 to 3 seconds. If the application time of the ultrasonic wave is less than 1 second, the generation of bubbles may not be sufficiently suppressed, and if it exceeds 5 seconds, the productivity may be inferior.
As for the timing of the ultrasonic wave and heating and pressurization, the application of the ultrasonic wave may be started within the pressurization time and the application may be completed within the pressurization time.
In this embodiment, provisional pressure bonding is performed while applying ultrasonic waves, but generation of bubbles can also be prevented by applying microwaves.

Embodiment 3
In this embodiment, the anisotropic conductive adhesive film is temporarily bonded to the circuit member while the temporary bonding portion of the circuit member is evacuated.
In the present embodiment, since the temporary press-bonding portion is evacuated, it is possible to prevent the generation of bubbles.

Hereinafter, the present invention will be specifically described by way of examples.
Production example [Manufacture of anisotropic conductive adhesive film]
(1) Synthesis of phenoxy resin (Ph-1) 45 g of 4,4- (9-fluorenylidene) -diphenol, 50 g of 3,3 ′, 5,5′-tetramethylbiphenol diglycidyl ether were added to 1000 ml of N-methylpyrrolidione. Into this, 21 g of potassium carbonate was added and stirred at 110 ° C. After stirring for 3 hours, the solution was added dropwise to a large amount of methanol, and the generated precipitate was filtered to obtain 75 g of phenoxy resin (Ph-1). As a result of measuring the molecular weight of Ph-1 with Tosoh GPC8020 (columns are Tosoh TSKgel G3000H _XL and TSKgel G4000H _XL , flow rate 1.0 ml / min), Mn = 12,500, Mw = 30,300, Mw / Mn in terms of polystyrene = 2.
42.

(2) Synthesis of phenoxy resin (Ph-2) Tetrabromobisphenol A (manufactured by Teijin Chemicals Ltd., FG-2000) was added to a 2-liter four-necked flask equipped with a nitrogen introduction tube, a thermometer, a cooling tube and a mechanical stirrer. ) 33.83 g, bisphenol A type epoxy resin (manufactured by Tohto Kasei Co., Ltd., YD-8125, molecularly distilled product, epoxy equivalent 172 g / equivalent) 205.56 g and N, N-dimethylacetamide 1257 g were put in a uniform nitrogen atmosphere. Stir until mixed. Next, 0.94 g of lithium hydroxide was added and reacted at 120 ° C. for 9 hours while gradually raising the temperature. The reaction was monitored by measuring the viscosity of the reaction solution at regular time intervals until the viscosity did not increase. After completion of the reaction, the reaction solution was allowed to cool, and about 420 g of activated alumina (200 mesh) was added thereto and left overnight. The activated alumina was filtered to obtain an N, N-dimethylacetamide solution of phenoxy resin. Next, in a 1 liter four-necked flask equipped with a nitrogen introduction tube, a thermometer, a cooling tube, and a mechanical stirrer, 807.62 g of the obtained phenoxy resin in N, N-dimethylacetamide solution, terminal carboxyl group-containing butadiene-acrylonitrile 50.88 g of a copolymer (manufactured by Ube Industries, Ltd., Hycar CTBNX1009-SP) was added, and thoroughly purged with nitrogen while stirring and mixing. Next, the mixture was stirred and mixed in a nitrogen atmosphere, and heated for 8.5 hours in a state where the solvent was refluxed while gradually raising the temperature. After cooling, it was added dropwise to a large amount of methanol, and the produced precipitate was filtered to obtain 470 g of phenoxy resin (Ph-2).

(3) Production of circuit connection material composition Phenoxy resin (Ph-1) (Ph-1 / toluene / ethyl acetate = 40/30/30 parts by weight) synthesized in the above (1) and (2) 100 parts by weight 20 parts by weight of a phenoxy resin (Ph-2) (Ph-2 / toluene / ethyl acetate = 50/25/25 parts by weight) solution and as a radical polymerizable compound, isocyanuric acid ethylene oxide-modified diacrylate (Toagosei Co., Ltd.) M-313) 10 parts by weight, urethane acrylate (Shin Nakamura Chemical Co., Ltd., NK Oligo U-108) 40 parts by weight, 1,1-bis (t-hexylperoxy) -3 as a radical generator, 5,5-trimethylcyclohexane (Nippon Yushi Co., Ltd., Perhexa TMH) 5 parts by weight, Ni / Au plated polystyrene particles (flat A circuit connecting material composition was prepared by mixing 10 parts by weight of a uniform particle size of 4 μm and 10 parts by weight of a silane coupling agent (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6030).

(4) Production of anisotropic conductive adhesive film Using a circuit connection material composition produced in (3) above as a support, a 40 μm thick silicone-treated polyethylene terephthalate film was used, and the circuit connection material composition was formed thereon with a roll coater. The anisotropic conductive adhesive film which apply | coated and dried for 5 minutes at 70 degreeC formed the circuit connection material layer with a film thickness of 30 micrometers on the support body was produced.

Reference examples 1 and 2
An anisotropic conductive adhesive film produced in Production Example ( Reference Example 1 ) and a commercially available anisotropic conductive film AC-8604 (manufactured by Hitachi Chemical Co., Ltd.) ( reference ) on a glass substrate having an ITO (Indium Tin Oxide) comb electrode pattern Example 2 ) was laminated using a laminator (manufactured by DuPont) at 40 ° C., 0.5 m / min without pressure, and then temporarily fixed at 65 ° C. and 1 MPa by heating and pressurization. The support was removed.
Further, a silicone moisture-proofing agent was potted on the film (GE Toshiba Silicone, TSE3996 White). The prepared sample was observed with a microscope. The case where only bubbles having a diameter of 10 μm or less exist between the electrode and the film is evaluated as ◯, the case where bubbles exceeding 10 μm in diameter are present as Δ, and the case where bubbles of 25 μm or more are present is evaluated as ×, The results are shown in Table 1. Then, it was left to stand for 300 hours in a constant temperature and humidity chamber having a temperature of 60 ° C. and a humidity of 90% RH while applying a pulse voltage of 0 V to 5 V and a frequency of 1 kHz. Thereafter, the glass substrate was taken out and observed with a microscope. The case where the electrode was corroded was evaluated as x, and the case where no corrosion was observed was evaluated as ◯. The results are shown in Table 1.

Examples 1 and 2
An anisotropic conductive adhesive film (Example 1 ) produced in the production example and a commercially available anisotropic conductive film AC-8604 (manufactured by Hitachi Chemical Co., Ltd.) (implemented) on a glass substrate having an ITO (Indium Tin Oxide) comb electrode pattern Example 2 ) was temporarily pressure-bonded by heating and pressurizing at 65 ° C. and 1 MPa while applying ultrasonic waves (20 KHz) for 3 seconds using an ultrasonic wave application and heating and pressing device SH50MP (manufactured by Altex Co., Ltd.). The support was removed. Evaluation was performed in the same manner as in Reference Example 1, and the results are shown in Table 1.

Comparative Examples 1 and 2
An anisotropic conductive adhesive film produced in Production Example (Comparative Example 1) and a commercially available anisotropic conductive film AC-8604 (manufactured by Hitachi Chemical Co., Ltd.) (compared to a glass substrate having an ITO (Indium Tin Oxide) comb electrode pattern) Example 2) was temporarily fixed by heating and pressing at 65 ° C. and 1 MPa, and the film support was removed. Evaluation was performed in the same manner as in Reference Example 1, and the results are shown in Table 1.

[Table 1]
Reference Example 1 Reference Example 2 Example 1 Example 2 Comparative Example 1 Comparative Example 2
Air bubbles ○ ○ △ △ × ×
Corrosion ○ ○ ○ ○ × ×

According to the method for temporarily bonding an anisotropic conductive adhesive film of the present invention, a circuit member in which the generation of bubbles is suppressed in the bonded portion can be obtained, and manufacturing of a circuit member such as a liquid crystal panel with a low risk of migration is enabled. .
The present invention can be widely applied not only to a liquid crystal panel but also to a connection method using an anisotropic conductive adhesive sheet.

1 Anisotropic conductive adhesive film 2 Glass substrate (circuit member)
3 Winding roll 4 Work plate 10 Laminator 11 Pressure roller 12 Cutter 30 Ultrasonic vibration and heating and pressurizing device

Claims (2)

  A method for temporarily pressing an anisotropic conductive adhesive film, wherein the anisotropic conductive adhesive film is temporarily bonded to a circuit member while applying ultrasonic waves or microwaves.   2. The anisotropic structure according to claim 1, wherein the total area of bubbles formed between the anisotropic conductive adhesive film and the circuit member is 5% or less of the contact area between the anisotropic conductive adhesive film and the circuit member. A method for temporarily bonding a conductive adhesive film.

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