JPH1187429A - Mounting method for semiconductor chip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the reliability by suppressing production of bubble and increasing the bonding power in the case of mounting a semiconductor chip onto a circuit board through an anisotropic conductive thereby preventing a thermal strain from being developed in the semiconductor chip and the circuit board. SOLUTION: After an anisotropic conductive adhesive 18 is applied onto a circuit board 12, the circuit board 12 is heated temporarily at a temperature lower than the curing temperature of the anisotropic conductive adhesive 18 by means of a heating jig 20. Subsequently, a semiconductor chip 13 is set on the circuit board 12 and thermocompression-bonded by means of a hot press 19 thus curing the anisotropic conductive adhesive 18. Generation of thermal strain can be prevented by heating the circuit board 12 also from the lower surface side at a temperature lower than the heating temperature of the semiconductor chip 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor chip mounting method for mounting a semiconductor chip provided with protruding electrodes on a circuit board on which a wiring pattern is formed, and more particularly to a method of mounting a semiconductor chip using an anisotropic conductive adhesive. The present invention relates to a mounting method for connecting an electrode to a wiring pattern on a circuit board and fixing a semiconductor chip to the circuit board.

[0002]

2. Description of the Related Art For example, a method of mounting a semiconductor chip (device) for driving a liquid crystal on a glass substrate of a liquid crystal panel using an anisotropic conductive adhesive has been put to practical use. FIG. 6 is a plan view of FIG. 5 and a cross-sectional view taken along the line AA of FIG. 5, and FIG. 6 is a cross-sectional view showing each step of mounting the semiconductor chip. This will be described with reference to FIG.

As shown in FIG. 5, a liquid crystal display device has a first substrate 11 and a second substrate 1 which are circuit substrates of a liquid crystal panel.
A wiring pattern 15 for transmitting a signal to the liquid crystal display unit is formed in the margins 16 and 16, and a plurality of liquid crystal driving semiconductor chips 13 are mounted thereon. As a material of the wiring pattern 15, an indium tin oxide (ITO) film or a tin oxide film which is a transparent conductive film is used.

The semiconductor chips 13 mounted on the margins 16 of the substrates 11 and 12 on which the wiring patterns 15 are respectively formed are adhered by an anisotropic conductive adhesive 18 as shown in FIG. The anisotropic conductive adhesive 18 is made of metal particles such as silver or solder having a diameter of 5 μm to 10 μm, or gold-plated on the surface in order to impart conductivity to an insulating epoxy adhesive. It is obtained by mixing conductive particles 18a such as plastic resin particles.

[0005] The conductive particles 18a contained in the anisotropic conductive adhesive 18 are interposed between the wiring pattern 15 and the protruding electrodes 14 provided on the semiconductor chip 13, so that both are electrically connected. As the anisotropic conductive adhesive 18, as shown in FIG. 11, an anisotropic conductive film (Anisotro conductive film) is provided between the base film 181 and the cover film 182.
pic Conductuve Film (ACF) 180 sandwiches a film. The anisotropic conductive film 180 has conductive particles 18a in a thermosetting epoxy resin as an adhesive layer.
Is mixed in.

The conductive particles 18a have a spherical shape with a diameter of about 5 μm as shown in FIG.
A gold plating layer 18a2 is formed on the surface of 8a1, and the surface is further covered with an insulating layer 18a3. Therefore, in the anisotropic conductive film 180, the conductive particles 18
a are insulated from each other, and when heated and pressurized by being sandwiched between conductive materials in the thickness direction, the insulating layer 1 of the conductive particles 18a is formed.
8a3 is broken and becomes conductive. Other parts of conductive particles 18
a does not conduct in the plane direction of the anisotropic conductive film 180 because the insulating layer 18a3 is not broken.

[0007] As shown in FIG. 7, the process of mounting the semiconductor chip is as follows.
The anisotropic conductive adhesive 18 is transferred and arranged on the portion where the semiconductor chip 13 is mounted.

For example, the cover film 1 shown in FIG.
After peeling off 82 and attaching anisotropic conductive film 180 on substrate 12, base film 181 is peeled off. Next, in step 2, the protruding electrode 14 of the semiconductor chip 13 is aligned with the wiring pattern 15 of the opposing substrate 12, and the semiconductor chip 13 is placed on the substrate 12 via the anisotropic conductive adhesive 18.
Place on top.

Then, in step 3, the semiconductor chip 13 is heated and thermocompression-bonded to the second substrate 12 by using a heating and pressing jig 19 having a built-in heater 19a. To cure.

Thus, in step 4 where the anisotropic conductive adhesive 18 is cured, the semiconductor chip 13 is bonded onto the substrate 12, and each of the bump electrodes 14 of the semiconductor chip 13 and the wiring pattern 15 on the substrate 12 are bonded. A plurality of conductive particles 18a are interposed between each other, whereby each protruding electrode 14 and the wiring pattern 15 are conducted.

The anisotropic conductive adhesive 18 has conductive particles 18a dispersed in an insulating epoxy-based adhesive, or further has an anisotropic conductive film 180 as shown in FIG. 11 and FIG. Since the outer peripheral surface of the conductive particles 18a is covered with the insulating layer 18a3,
Conductive particles 18a sandwiched between the wiring pattern 15
The other conductive particles 18a are insulated from each other, and do not short-circuit between the protruding electrodes 14 or between the wiring patterns 15.

[0012]

However, in such a conventional method of mounting a semiconductor chip, when the anisotropic conductive adhesive 18 is cured by heating, it is contained in the anisotropic conductive adhesive 18. Volatile components (diluent and water) and air entrained are generated as bubbles between the semiconductor chip 13 and the substrate 12.

As a result, as shown in FIG. 8, bubbles 21 are generated on the bonding surface of the epoxy adhesive of the anisotropic conductive adhesive 18 between the semiconductor chip 13 and the substrate 12. Therefore, the epoxy adhesive of the anisotropic conductive adhesive 18 is not completely filled between the semiconductor chip 13 and the substrate 12, and the adhesive strength is reduced. Thereby, the semiconductor chip 13 and the substrate 1
2 between the projection electrode 14 and the wiring pattern 1
There has been a problem that conduction between the wires 5 may be interrupted.

Further, after the semiconductor chip 13 is thermocompression-bonded to the substrate 12, thermal distortion occurs between the semiconductor chip 13 and the substrate 12. For example, comparing the thermal expansion coefficients of a borosilicate glass substrate, which is often used for the liquid crystal panel substrate 12, and a semiconductor chip 13, which is mainly composed of silicon, the glass substrate has a larger thermal expansion coefficient. After the substrate 13 is thermocompression-bonded to the substrate 12 to cure the anisotropic conductive adhesive, when the temperature decreases and returns to room temperature, due to the difference in the coefficient of thermal expansion between the semiconductor chip 13 and the substrate 12, The amount of shrinkage differs between materials.

FIG. 9 shows the amount of thermal expansion of the borosilicate glass substrate and the semiconductor chip with respect to the heating temperature. According to this figure, the thermal expansion coefficient αglas of a borosilicate glass substrate
s is ^{αglass = 51 × 10 ~ 7 /} ℃, thermal expansion coefficient ArufaIC semiconductor chip silicon is the main constituent material is a ^{αIC = 24.2 × 10 ~ 7 /} ℃.

That is, since the first and second substrates 11 and 12 shown in FIGS. 5 to 7 are glass substrates, they have a thermal expansion coefficient approximately twice that of the semiconductor chip 13. In general,
When a temperature difference of ΔT is applied to a material having a length of 1 (m) and a thermal expansion coefficient α, the elongation L (m) of the material is represented by L = α × 1 × ΔT.

Here, at 210 ° C., the anisotropic conductive adhesive 18
Is cured at 250 ° C.
Temperature must be applied. The pressing time is 5 seconds to 10 seconds. When the pressing time is set to 5 seconds to 10 seconds, the temperature of the substrate 12 increases only to about 100 ° C.

Assuming that the room temperature is 20 ° C., the amount of elongation generated in the substrate (glass substrate) 12 and the semiconductor chip 13 is calculated. The length of one side of the semiconductor chip is 15 mm,
When the elongation due to thermal expansion is calculated symmetrically on one half, the amount of elongation of the substrate 12 at this time is (15 mm ÷ 2) × 51 × 10 × ⁷ × (10
(0 ° C.-20 ° C.) = 0.030600 mm.

Meanwhile, the elongation amount of the semiconductor chip (15mm ÷ 2) × 24.2 × 10 ~ 7 × (100 ℃ -2
0 ° C) = 0.0041745 mm 2. Therefore, the deviation between the substrate 12 and the semiconductor chip 13 is 0.0041745 mm−0.0030600 mm =
0.0011145 mm 2, which means that the substrate 12 extends more by about 1 μm.

When these materials are returned to room temperature of 20 ° C. in a state where the difference in elongation exists, the bonding surface of the substrate 12 and the semiconductor chip 13 (the projecting electrode 1
4 and the wiring pattern 15, the semiconductor chip 13 and the substrate 1
2), there is a problem that thermal distortion occurs due to the difference in shrinkage between the two, and peeling occurs. FIG. 10 shows the temperature of the borosilicate glass substrate and the distortion of the glass substrate when the semiconductor chip for driving a liquid crystal is heated to 250 ° C.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems in such a conventional method of mounting a semiconductor chip using an anisotropic conductive adhesive. So that there is no difference in the amount of shrinkage between the semiconductor chip and the circuit board after thermocompression bonding, so that the semiconductor chip does not peel off from the circuit board or poor conduction between the protruding electrodes and the wiring pattern does not occur. ,
An object is to realize highly reliable mounting of a semiconductor chip on a circuit board.

[0022]

In order to achieve the above object, the present invention provides a method for mounting a semiconductor chip on a circuit board as described above, wherein after arranging an anisotropic conductive adhesive on the circuit board, Prior to placing the semiconductor chip on the circuit board, the circuit board on which the anisotropic conductive adhesive is placed is temporarily heated at a temperature lower than the curing temperature of the anisotropic conductive adhesive.

As described above, by temporarily heating the circuit board on which the anisotropic conductive adhesive is disposed, the volatile component contained in the anisotropic conductive adhesive is volatilized before mounting the semiconductor chip, and Almost no air bubbles can be generated in the adhesive during thermocompression bonding. Therefore, compared to the conventional semiconductor chip mounting method, the amount of bubbles generated between the semiconductor chip and the circuit board is remarkably reduced, and highly reliable mounting can be performed.

According to the present invention, in the step of heating the semiconductor chip while applying pressure to the circuit board to cure the anisotropic conductive adhesive as described above, the circuit board is placed on the side opposite to the surface on which the semiconductor chip is arranged. The present invention also provides a semiconductor chip mounting method characterized in that the semiconductor chip is heated at a temperature lower than the heating temperature for the semiconductor chip.

As described above, the circuit board is also heated and its temperature is adjusted so that the thermal expansion of the circuit board is substantially equal to the thermal expansion of the semiconductor chip. Therefore, no distortion occurs between the circuit board and the semiconductor chip. Accordingly, peeling of the semiconductor chip and poor conduction between the protruding electrode and the circuit pattern do not occur, and highly reliable mounting can be performed.

In the step of temporarily heating the circuit board on which the anisotropic conductive adhesive is arranged at a temperature lower than the curing temperature of the anisotropic conductive adhesive, and the step of curing the anisotropic conductive adhesive, The circuit board is also heated from a surface opposite to the surface on which the semiconductor chip is arranged, at a temperature lower than the heating temperature for the semiconductor chip, so that generation of air bubbles is almost eliminated, and between the circuit board and the semiconductor chip. In this case, the occurrence of distortion can be prevented, and more reliable mounting can be realized.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for mounting a semiconductor chip according to the present invention will be described below with reference to the drawings.
In the following description of the embodiment, a method of mounting a semiconductor chip (device) for driving a liquid crystal on a glass substrate of a liquid crystal panel will be described as an example, similarly to the conventional example described with reference to FIGS.

FIG. 1 is a sectional view similar to FIG. 7 showing each step of the first embodiment of the method of mounting a semiconductor chip according to the present invention, and the same parts as those in FIG. is there. First, in a first step 1 shown in FIG. 1, a second substrate (hereinafter simply referred to as “substrate”) 12 which is a circuit substrate of a liquid crystal panel
The anisotropic conductive adhesive 18 is arranged in the margin 16 at a position where the semiconductor chip 13 is mounted.

The arrangement of the anisotropic conductive adhesive 18 is shown in FIG.
It is good to paste and transfer the anisotropic conductive film (ACF) shown in 1 above, but it is also possible to print a paste or use a heating head heated from 80 ° C to 100 ° C,
It can also be applied by a dispenser robot. This anisotropic conductive adhesive 18 is transferred to a thickness of 20 μm to 100 μm to the same size as the semiconductor chip 13 to be mounted or to a range about 2 mm larger than its outer shape.

In the next step 2, the substrate 12 on which the anisotropic conductive adhesive 18 is disposed is temporarily heated from the back surface by using a heating jig 20. This temporary heating is performed at a temperature of 100 ° C. to 120 ° C. lower than the curing temperature of the anisotropic conductive adhesive 18 for 5 seconds to 1 second.
Heat for 0 seconds. The heating jig 20 has a built-in heater 20a inside a stainless steel material, and is set so that the entire area of the substrate 12 where the semiconductor chip 13 is mounted can be heated.

Thereafter, in step 3, the protruding electrodes 14 formed on the semiconductor chip 13 are aligned with the wiring patterns 15 formed on the substrate 12 by using an indium tin oxide (ITO) film or a tin oxide film as a transparent electrode film. Then, the semiconductor chip 13 is attached to the second substrate 12 by the anisotropic conductive adhesive 18.
Mounted via

Then, in step 4, the semiconductor chip 13 is heated and thermocompression-bonded to the glass substrate using a heating and pressing jig 19 having a built-in heater 19a, and the anisotropic conductive adhesive 18 is cured. Let it. The temperature during thermocompression bonding is 150 ° C
To 260 ° C., preferably 180 ° to 200 ° C., at a pressure in the range of 3 kg to 20 kg. The pressing force can be applied by a driving force of an air cylinder or a motor.

In this step, the semiconductor chip 13 is bonded onto the substrate 12, and a plurality of conductive particles 18 a are sandwiched between each of the protruding electrodes 14 of the semiconductor chip 13 and the wiring pattern 15 on the substrate 12. Accordingly, each protruding electrode 14 and the wiring pattern 15 are conducted.

Before the anisotropic conductive adhesive 18 is completely cured, the substrate on which the anisotropic conductive adhesive 18 is disposed is temporarily heated, so that volatile components contained in the anisotropic conductive adhesive 18 are evaporated. Then, the entrained bubbles are also defoamed, and as shown in FIG. 2, the generation of bubbles 21 when the anisotropic conductive adhesive 18 is cured is extremely reduced.

Since the generation of bubbles is reduced, compared with the case where the generation of bubbles by the conventional mounting method is large,
Anisotropic conductive adhesive 1 between substrate 12 and semiconductor chip 13
8 is densely filled, the adhesive strength is increased, and the force for holding the conductive particles 18a sandwiched between the protruding electrode 14 and the wiring pattern 15 is also increased, so that the connection resistance value is reduced and stable. I do.

Here, a comparison experiment between a case where a semiconductor chip is actually mounted on a circuit board by a conventional method and a case where the semiconductor chip is mounted by a method according to the present invention is described. The comparison experiment and the result will be described.

In the experimental method, a substrate was prepared by pasting an anisotropic conductive adhesive on a glass substrate on which an ITO wiring pattern was formed so that the connection resistance value could be measured. The adhesive was positioned on a glass substrate and heated at a temperature of about 180 ° C. for about 20 seconds to cure the adhesive.

In the mounting method of the present invention, the glass substrate to which the anisotropic conductive adhesive has been adhered is left on a hot plate heated to about 100 ° C. for about 10 seconds, and After evaporating the volatile components, the semiconductor chip was positioned on the glass substrate and heated at a temperature of about 180 ° C. for about 20 seconds to cure the adhesive.

The sample manufactured by the conventional mounting method and the sample manufactured by the mounting method of the present invention are left for 500 hours in a furnace set in a high-temperature and high-humidity atmosphere at a temperature of 85 ° C. and a humidity of 85%. A durability test was performed. FIG.
Is a diagram (graph) showing a change in connection resistance value between the protruding electrode of the semiconductor chip and the wiring pattern on the glass substrate according to the sample of the conventional mounting method and the sample of the mounting method of the present invention in the durability test. is there.

As can be seen from FIG. 3, when the connection resistance after leaving for 500 hours is compared, the connection resistance in the sample of the conventional mounting method is about 32Ω, which is considerably larger than the initial connection resistance (about 5Ω). Although increasing, the connection resistance value in the sample of the mounting method of the present invention is about 10Ω, which is only slightly increased from the initial connection resistance (about 2Ω).

As described above, when the semiconductor chip is mounted by the method of the present invention, the connection resistance can be kept lower for a long time than when the semiconductor chip is mounted by the conventional method.

Next, a second embodiment of the semiconductor chip mounting method according to the present invention will be described with reference to FIG.
A case where a semiconductor chip for driving liquid crystal is mounted on the liquid crystal panel shown in FIG. 6 will be described. FIG. 4 is a cross-sectional view showing a mounting step of the semiconductor chip according to the second embodiment, and corresponds to a cross-section along the line AA in FIG. 5, as in FIGS. In FIG. 4, the same parts as those in FIGS. 7 and 1 are denoted by the same reference numerals.

In the second embodiment, steps 1 and 2 shown in FIG. 4 are the same as steps 1 and 2 of the conventional example shown in FIG. That is, in step 1, a second substrate (hereinafter simply referred to as a “substrate”) that is a circuit substrate of a liquid crystal panel is used.
An anisotropic conductive adhesive 18 is arranged by transfer or the like in a region where the semiconductor chip is to be mounted on the margin 16 of the 12).

In step 2, the semiconductor chip 13 is arranged on the substrate 12 via the anisotropic conductive adhesive 18 by aligning the projecting electrodes 14 of the semiconductor chip 13 with the wiring patterns 15 of the substrate 12 facing the semiconductor chip 13.

Step 3 is a step unique to this embodiment.
When the semiconductor chip 13 is heated and thermocompression-bonded to the substrate 12 using a heating and pressing jig 19 having a built-in heater 19a, and the anisotropic conductive adhesive 18 is cured,
At the same time, the substrate 12 is heated from the lower surface (the surface opposite to the surface on which the semiconductor chips 13 are arranged) by the heating jig 20 incorporating the heater 20a. The heating temperature is lower than the heating temperature of the semiconductor chip 13, and a specific example thereof will be described later.

When the anisotropic conductive adhesive 18 is hardened, the semiconductor chip 13 is bonded on the second substrate 12 as shown in step 4, and the semiconductor chip 13 is placed between the protruding electrode 14 of the semiconductor chip 13 and the wiring pattern 15. By the conductive particles 18a sandwiched between the wirings, conduction between the protruding electrode 14 and the wiring pattern 15 is established.

The temperature applied to the semiconductor chip 13 during the thermocompression bonding in the step 3 is 150 ° C. to 260 ° C., preferably 180 ° C.
C. to 240.degree. C. and a pressure in the range of 1 kg to 30 kg. The crimping time is 5 to 10 seconds. By the way, when the pressure bonding time is between 5 seconds and 10 seconds, the temperature of the glass substrate is
It only rises to about 100 ° C.

As shown in FIG. 9, when a substrate 12 which is a borosilicate glass substrate and a semiconductor chip 13 are heated at the same temperature, a glass substrate having a larger coefficient of thermal expansion is larger than a semiconductor chip. Large elongation. The hatched portion in FIG. 9 indicates the amount of deviation in the amount of thermal expansion between the glass substrate and the semiconductor chip. 0.00502 at 250 ° C
There is a shift of 5 mm. In order to eliminate this difference in the amount of elongation, a heating jig 20 is
2 is heated to adjust the temperature difference from the semiconductor chip 13.

The temperature of the glass substrate shown in FIG.
From a diagram (graph) showing the relationship between the amount of thermal distortion with the semiconductor chip at a temperature of ° C., when the semiconductor chip 13 is heated to 250 ° C., it is determined how much the substrate 12 which is a glass substrate is heated to eliminate the distortion. I understand. When the temperature of the substrate 12 is set to about 130 ° C., the amount of thermal strain becomes almost zero. Hereinafter, this point will be described together with numerical values.

When the room temperature is set to 20 ° C., the amount of elongation generated in the glass substrate and the semiconductor chip is calculated. When the length of one side of the semiconductor chip is set to 15 mm and the elongation due to thermal expansion occurs symmetrically on one side, the amount of elongation of the semiconductor chip 13 heated to 250 ° C. is (15 mm ÷ 2) × 24 0.2 × 10 ~ ⁷ × (250 ℃ -2
(0 ° C.) = 0.0041745 mm 2.

At this time, the extension amount of the substrate 12
Is heated to 130 ° C., (15 mm ÷ 2) × 51 × 10 to ⁷ × (130 ° C.-20
C) = 0.0042075 mm. Therefore, the deviation between the glass substrate and the semiconductor chip is 0.0041745 mm-0.00004275 mm = 0.
000330 mm 2, and the amount of thermal strain can be reduced to almost zero.

In calculation, the substrate 12 is 129.1372.
By heating to about ° C, thermal distortion can be completely eliminated. From the above, it can be seen that when a semiconductor chip for driving liquid crystal is mounted on a borosilicate glass substrate, it is preferable to heat the glass substrate to about 130 ° C. with a heating jig.

Even when a semiconductor chip is mounted on a circuit board using another material having a different coefficient of thermal expansion, or when the curing temperature of the anisotropic conductive adhesive changes, the semiconductor chip and the semiconductor chip are determined based on the coefficient of thermal expansion of those materials. By calculating a temperature at which the heat shrinkage becomes the same and adjusting the temperature on the circuit board side to mount the semiconductor chip, mounting without thermal distortion can be performed.

Further, the third embodiment of the semiconductor chip mounting method according to the present invention can be obtained by combining the first embodiment described above with the second embodiment. That is, in the step of mounting the semiconductor chip according to the first embodiment of the present invention shown in FIG. 1, step 4 of the above-described second embodiment shown in FIG. Can be.

Specifically, in step 2, the substrate 12 on which the anisotropic conductive adhesive 18 is disposed is temporarily heated by a heating jig 20 at a temperature lower than the curing temperature of the anisotropic conductive adhesive 18. In the step 3 of curing the anisotropic conductive adhesive, the substrate 12 is also moved from the lower surface thereof to the heating jig 2.
In the case of 0, the semiconductor chip 13 is both heated at a temperature lower than the heating temperature of the heating jig 19.

As a result, the generation of bubbles between the anisotropic conductive adhesive 18 and the semiconductor chip 13 and the substrate 12 is almost eliminated, and the generation of thermal distortion between the substrate 12 and the semiconductor chip 13 is also prevented. A highly reliable mounting can be realized.

[0057]

As described above, in the method of mounting a semiconductor chip according to the present invention, the anisotropic conductive adhesive is heated and included in the adhesive before placing the semiconductor chip on the circuit board. After the volatile components are blown off, the semiconductor chip is mounted and thermocompression-bonded, which can suppress the generation of bubbles when the anisotropic conductive adhesive is cured. The chip can be mounted on a circuit board.

When the semiconductor chip is thermocompression-bonded, the semiconductor chip is thermocompression-bonded while the circuit board is heated from the lower side in order to eliminate a difference in elongation due to a difference in thermal expansion coefficient between the circuit board and the semiconductor chip. Thereby, when the heat curing of the anisotropic conductive adhesive is completed and the temperature of the circuit board and the semiconductor chip returns to room temperature, a good connection state without thermal distortion can be obtained. By carrying out both of these, it is possible to realize mounting of a more reliable semiconductor chip on a circuit board.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a semiconductor chip mounting method according to the present invention.
FIG. 7 is a cross-sectional view similar to FIG. 6, illustrating each step of the embodiment.

FIG. 2 is a plan view showing a state of bubbles generated in the anisotropic conductive adhesive when the first embodiment of the present invention is carried out.

FIG. 3 shows a sample of a conventional mounting method and a first example of the present invention.
FIG. 10 is a diagram showing a change over time of a connection resistance value in a reliability test using a sample in the mounting method according to the embodiment.

FIG. 4 shows a second embodiment of the semiconductor chip mounting method according to the present invention.
FIG. 7 is a cross-sectional view similar to FIG. 6, illustrating each step of the embodiment.

FIG. 5 is a plan view of a liquid crystal display device to which the semiconductor chip mounting method according to the present invention is applied.

FIG. 6 is a partially enlarged sectional view taken along line AA of FIG. 5;

FIG. 7 is a cross-sectional view similar to FIG. 6, illustrating each step of a conventional semiconductor chip mounting method.

FIG. 8 is a plan view showing a state of bubbles generated in an anisotropic conductive adhesive when a conventional semiconductor chip mounting method is performed.

FIG. 9 is a diagram showing a thermal expansion amount with respect to a temperature of a borosilicate glass substrate and a semiconductor chip.

FIG. 10 is a diagram showing the amount of thermal distortion between a borosilicate glass substrate and a semiconductor chip at 250 ° C. at each temperature.

FIG. 11 is a cross-sectional view of an anisotropic conductive film which is an example of an anisotropic conductive adhesive.

FIG. 12 is a perspective view showing an enlarged conductive particle mixed in the anisotropic conductive film shown in FIG.

[Explanation of symbols]

 11: First substrate 12: Second substrate (substrate) 13: Semiconductor chip 14: Projecting electrode 15: Wiring pattern 16: Margin 18: Anisotropic conductive adhesive 18a: Conductive particles 19: Heating and pressing jig 20: heating jig 21: air bubble 180: anisotropic conductive film

Claims (3)

[Claims] 1. A method for mounting a semiconductor chip provided with protruding electrodes on a circuit board on which a wiring pattern is formed, the method comprising: disposing an anisotropic conductive adhesive on the circuit board; Temporarily heating the circuit board on which the anisotropic conductive adhesive is arranged at a temperature lower than the curing temperature of the anisotropic conductive adhesive; and aligning the protruding electrodes of the semiconductor chip with the wiring pattern on the circuit board. Placing the semiconductor chip on the circuit board; and heating the semiconductor chip while applying pressure to the circuit board to cure the anisotropic conductive adhesive. Implementation method. 2. A method of mounting a semiconductor chip provided with a protruding electrode on a circuit board having a wiring pattern formed thereon, the method comprising: disposing an anisotropic conductive adhesive on the circuit board; Aligning the projecting electrodes of the semiconductor chip with the wiring pattern on the circuit board, and arranging the semiconductor chip on the circuit board; heating the semiconductor chip while pressing the circuit board; Heating the anisotropic conductive adhesive from a surface opposite to the surface on which the semiconductor chip is arranged, at a temperature lower than the heating temperature for the semiconductor chip, to cure the anisotropic conductive adhesive. Implementation method. 3. The method of mounting a semiconductor chip according to claim 1, wherein in the step of curing the anisotropic conductive adhesive, the semiconductor chip is heated while being pressed against the circuit board,
A method of mounting a semiconductor chip, comprising heating the circuit board from a surface opposite to a surface on which the semiconductor chip is arranged at a temperature lower than a heating temperature for the semiconductor chip.