JP2002313852A - Method for mounting electronic component to substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an offset load to a substrate and a local rise of temperature and to improve the reliability when electronic components are mounted to the substrate by a thermo compression bonding through connecting members such as anisotropic conductors. SOLUTION: When a substrate 2a is large, all the electronic components 3 (31-35) on one terminal are mounted only after a thermo compression bonding tool 4 having a pressing surface length L has been operated several times for thermo compression bonding while being displaced. The thermo compression bonding tool 4 performs thermo compression bonding of the electronic components in sequence while changing its position. When an electronic component 3 (33) having a length smaller than the pressing surface length L is left, the tool 4 performs thermo compression bonding of the component 3 (33) with an electronic component 3 (32) which was bonded last but one instead of an electronic component 3 (34) which was bonded immediately before. As a consequence, since the offset load to the substrate 2a and the local rise of temperature is prevented, damages such as deformation and crack of the substrate 2a is prevented and reliable mounting can be efficiently performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting an electronic component on a substrate suitable for connecting and mounting an electronic component such as a driving IC on a terminal surface of a substrate constituting a liquid crystal display panel or a plasma display. About.

[0002]

2. Description of the Related Art In a liquid crystal display panel, a TCP (Tape Carrier Pack) is provided on a terminal surface of a glass substrate.
age) and electronic components such as flip chips are connected and mounted.

In a simple matrix type liquid crystal display panel, two liquid crystal layers are sandwiched between a pair of rectangular glass substrates, and the liquid crystal layers correspond to pixels arranged in a matrix on the substrate surface. Further, a scanning electrode and a data electrode are formed orthogonally to the X-Y direction.

The scanning electrodes and the data electrodes are respectively connected to wiring terminals formed on the terminal surfaces on the sides of the substrate, and electronic components such as ICs for driving each pixel are electrically connected to the anisotropic conductive material adhered on the wiring terminals. It is connected and mounted via a connection member such as a body. The electronic component mounted and connected is positioned and mounted on a connecting member such as an anisotropic conductor, and is temporarily press-bonded by a press-bonding tool, and then is fully press-bonded by a thermo-compression tool, that is, mounted on a substrate through pressing and heating. Is performed.

[0005] Each electronic component for driving each pixel is properly connected to each wiring terminal via a connecting member, respectively.
In order to assemble and manufacture a highly reliable liquid crystal display panel, in the temporary compression bonding step, each electronic component must be properly positioned and mounted on the terminal surface of the substrate. It is required that pressing and heating of each electronic component be performed properly and satisfactorily.

Therefore, in the final pressing step, all the electronic components arranged in a row are simultaneously mounted on each electronic component on one terminal surface by a single thermocompression operation using a thermocompression tool, and pressing and heating are performed. Is desired to be performed uniformly.

However, in recent years, display screens such as liquid crystal display panels have become increasingly larger, and it has been difficult for conventional thermocompression bonding tools to perform full compression of all electronic components on one terminal surface by a single pressing operation. It has become to. Also, simply increasing the size of the thermocompression bonding tool itself is not physically easy to thermocompress all of the electronic components arranged in a long line uniformly and simultaneously at the same time. Only when a plurality of thermocompression operations are performed while changing the relative position between the electronic components, a case in which all the electronic components arranged in a row are fully press-bonded occurs.

FIG. 5 and FIG. 6 are explanatory views of a conventional method of mounting electronic components on a substrate on which electronic components arranged in a row are mounted by a plurality of final press bondings. FIG. The pair of substrates 2a and 2b are temporarily pressed on the electronic component 3 via a connection member (not shown), placed on the transporting means 1, transported in the direction of arrow X and positioned, and one terminal surface of the substrate 2a. FIG. 4 is a plan view showing a state in which electronic components 3 of FIG. FIG. 6A is a cross-sectional view taken along the line AA of FIG. 5. In FIGS. 5 and 6, for the sake of explanation, five electronic components 3 (31, 32 , 33,34,3
5) are sequentially positioned with the thermocompression bonding tool 4 having the pressing surface length L corresponding to the two arrangement lengths,
This shows a state in which the main compression bonding is performed.

That is, the arrangement length D of the electronic components is a length obtained by adding a length less than the pressing surface length L to two (plural) times the pressing surface length L of the thermocompression bonding tool 4. Therefore, all the electronic components 3 (31, 32, 33, 3
4 and 35) are implemented by using FIG. 6A to FIG.
As shown in (c), pressing and heating operations are performed at least three times by the thermocompression bonding tool 4.

In this case, the pressing surface length L of the thermocompression bonding tool 4 is approximately 2/5 of the arrangement length D of the electronic components, and is less than 1/2 (L <D / 2)
As shown in FIG. 6C, when the thermocompression bonding tool 4 finally thermocompression-bonds the electronic component 3 (35), the thermocompression bonding tool 4
A part of the pressing surface protrudes largely from the electronic component 3 (35).

As a result, the thermocompression bonding tool 4 is
Since the substrate 2a surface is pressed in a cantilevered state by (35), an uneven load is applied to the electronic component 3 (35) and the lower substrate 2a surface, and there is a possibility that the glass substrate 2a may be cracked. .

Therefore, in order to avoid an unbalanced load on the substrate 2a, the relationship between the thermocompression bonding tool 4 and the substrate 2a is positioned as shown in FIG. ) Is pressed and heated together with the electronic component 3 (34) thermocompression-bonded immediately before, so that the pressing load on the surface of the substrate 2a can be made uniform.

[0013]

As described above, the thermocompression bonding tool 4 is placed on one terminal surface only when the thermocompression bonding tool 4 performs, for example, three or more thermocompression bonding operations on the enlarged substrates 2a and 2b. In this case, when it becomes necessary to perform thermocompression bonding of the electronic component 3 (35) having a length less than the pressing surface length L, as shown in FIG. The electronic component 3 (35) and the other electronic component 3 (34) pressed and heated immediately before are collectively thermocompression-bonded to avoid uneven load on the substrate 2a and damage the substrate 2a. Can be avoided.

However, the electronic component 3 (34) which has been completely press-bonded is continuously pressed and heated by the thermo-compression tool 5, and the electronic component 3 (34) itself is subjected to continuous two-time heating. The temperature rises and the lower substrate 2
The surface a was locally heated to a high temperature, possibly causing damage such as cracking.

[0015] By this continuous thermocompression bonding twice,
In order to avoid the occurrence of cracks or the like in the substrate 2a, in the mounting process, the electronic component 3 (34) which has been completely press-bonded immediately before and the substrate 2a of the portion on which the electronic component 3 is mounted are cooled, and the temperature is sufficiently reduced. It is conceivable that the final compression bonding is performed together with the remaining electronic component 3 (35).

That is, in the conventional method of mounting an electronic component on a substrate described above, the thermocompression bonding process is performed once between the thermocompression bonding process shown in FIG. 6B and the thermocompression bonding process shown in FIG. By providing a cooling period for sufficiently lowering the temperature of the electronic component 3 (34) and the substrate 2a, and then performing the thermocompression bonding operation shown in FIG. 7, the damage to the substrate 2a can be avoided.

However, in a manufacturing process of a liquid crystal display panel or the like, providing a time zone for cooling bothersomely between a plurality of main press-bonding operations by a thermo-compression tool lowers the manufacturing efficiency, resulting in a so-called throughput. (Throu
Therefore, improvement has been demanded because it leads to a reduction in ghput).

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for mounting an electronic component on a substrate with high reliability without avoiding damage to the substrate and without lowering manufacturing efficiency.

[0019]

According to the present invention, there is provided a mounting step in which a plurality of electronic components are arranged and mounted on a terminal surface of a substrate via a connecting member, and after the mounting step, the terminal is provided. In a method of mounting an electronic component on a substrate, comprising: a thermocompression bonding step in which a thermocompression bonding tool shifts a position with respect to an electronic component on a surface; And pressing the substrate together with other electronic components other than the electronic component.

As described above, according to the method for mounting an electronic component on a substrate according to the present invention, the electronic component on the substrate is pressed and mounted together with electronic components other than the electronic component that has been thermocompression-bonded immediately before.

Therefore, even if there is an electronic component which is thermocompression-bonded twice, since continuous thermocompression is not performed, a local temperature rise in the substrate is suppressed and the thermocompression operation performed twice. In the meantime, thermocompression bonding of another electronic component is performed, so that a reduction in manufacturing efficiency can be substantially avoided.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a method for mounting an electronic component on a substrate according to the present invention will be described below in detail with reference to FIGS. The same components as those of the conventional method of mounting electronic components on a substrate shown in FIGS. 5 to 7 are denoted by the same reference numerals, and detailed description is omitted.

FIGS. 1 and 2 are a plan view and a sectional view, respectively, for explaining a first embodiment of a method for mounting an electronic component on a substrate according to the present invention.

As shown in the plan view of FIG. 1, five electronic components 3 (3) are connected via a connecting member (not shown) such as an anisotropic conductor.
1, 32, 33, 34, and 35) are mounted on one terminal surface by temporary crimping, and are conveyed by the transfer table 1 in the direction of arrow X1 to the main crimping step.

As shown in FIG. 2A, which is a cross-sectional view taken along the line AA in FIG. 1, the substrate 2a on which the electronic components 3 (31 to 35) are mounted is positioned on the support base 5. After that, the thermocompression bonding tool 4 heated by the built-in heater is lowered in the direction of arrow Y by operating a cylinder (not shown), so that the pressed and heated first and second electronic components 3 are heated.
(31, 32) are connected to the substrate 2 via a connection member (not shown).
It is connected and mounted on the wiring terminal a.

The electronic component 3 (31, 32, 33, 34, 3)
The array length D of 5) is 2 (plural) times the pressing surface length L of the thermocompression bonding tool 4, similarly to the array length D of the conventional electronic components shown in FIGS. Since the length is smaller than the pressing surface length L, after the thermocompression bonding step shown in FIG. 2A, the steps shown in FIGS. 2B to 2C are further performed. Only after a total of 3 (plurality + 1) times of pressing and heating, all the electronic components 3 (31 to 35) can be fully crimp mounted on one terminal surface of the substrate 2a.

That is, first, as shown in FIG. 2A, the thermocompression bonding tool 4 is connected to the first and second electronic components 3 (3
After the final compression bonding of the first and second electronic components 3 (34, 35), as shown in FIG. 2B, the fourth and fifth electronic components 3 (34, 35) are thermally moved by the transfer table 1 in the direction of the arrow X1. It is positioned so as to face the crimping tool 4 and is completely crimped.

Fourth and fifth electronic components 3 (34, 35)
The thermocompression bonding tool 4 after the final press bonding of the substrate 2 is transported and moved by the transport table 1 in the direction of the arrow X2.
After being positioned as shown in FIG. 2 (c), the third electronic component 3 (33) that has been left
Pressing and heating together with the electronic component 3 (32) of
a.

As described above, in the final crimp mounting of all the electronic components 3 (31 to 35) arranged on one terminal surface of the substrate 2a, the remaining electronic components 3 (33) were thermocompression-bonded immediately before. Instead of the electronic components 3 (34, 35), the thermocompression bonding tool 4 is used to perform thermocompression bonding with the electronic components 3 (32) thermocompressed two times before.

Therefore, in the process of mounting the electronic component 3 on the substrate 2a, the thermocompression bonding tool 4 performs thermocompression bonding without protruding from the arrangement of the electronic components 3 in the longitudinal direction. Even if the third electronic component 3 (32) receives the thermocompression bonding twice, the same electronic component 3 (32) is not continuously thermocompression-bonded.
The temperature rise in the portion of the substrate 2a surface corresponding to (32) is suppressed. Therefore, without any reduction in manufacturing efficiency,
In addition, it is possible to avoid the occurrence of cracks and the like on the substrate 2a, and to implement highly reliable mounting of electronic components.

In the first embodiment, the thermocompression bonding tool 4 is used.
In order to thermocompression-bond all of the electronic components 3 (31 to 35), the order of the thermocompression bonding is determined by the first and second electronic components 3 (3
1, 32) → fourth and fifth electronic components 3 (34, 35)
→ The switching is performed as in the second and third electronic components 3 (32, 33). However, even if the order of the thermocompression bonding is simply changed, the local temperature rise of the substrate is avoided, and the reliability is improved. High implementation is possible.

FIG. 3 is a cross-sectional view showing a method of mounting an electronic component on a board according to the second embodiment, which is performed in a symmetrical order to the thermocompression bonding order in the first embodiment. is there.

That is, the second embodiment is different from FIG.
As shown in (a) to (c) of FIG. 3, the order of thermocompression of the electronic components 3 (31 to 35) by the crimping tool 4 is changed from the fourth and fifth electronic components 3 (34, 35) to the fourth. 1st and 2nd
Electronic component 3 (31, 32) → third and fourth electronic component 3 (33, 34), and the last third electronic component 3 (3,
The position adjustment is performed by the transporting means 1 so that the thermocompression bonding of 3) is performed together with the fourth electronic component 3 (34) thermocompression-bonded two times before. A highly reliable mounting can be performed while avoiding a local temperature rise.

FIG. 4 is a sectional view showing a third embodiment of the method of mounting an electronic component on a substrate according to the present invention. The order of thermocompression of electronic components 3 (31 to 35) by a thermocompression tool 4 is shown. , Second and third electronic components 3 (32, 33) → fourth
And the fifth electronic component 3 (34, 35) → the first and second electronic components 3 (31, 32) are switched and positioned.

According to the thermocompression bonding sequence shown in FIG.
Similarly to the first and second embodiments, the electronic component 3 that is thermocompression-bonded together with the electronic component 3 (31) that is thermocompression-bonded last
Since (32) is not thermocompression-bonded immediately before, the temperature of the portion of the substrate 2a corresponding to the position of the electronic component 3 (32) to be completely press-compressed must be lowered by the second thermocompression bonding. Thus, damage due to heating of the substrate 2a can be avoided.

Although not shown, the order of the third embodiment is symmetrical to the order of the thermocompression bonding of the third embodiment shown in FIG.
And fourth electronic component 3 (33, 34) → first and second electronic component 3 (31, 32) → fourth and fifth electronic component 3
The same effect can be obtained by performing as (34, 35).

In each of the first to third embodiments, the electronic component 3 thermocompression-bonded to the thermocompression tool 4 is used.
The positioning between (31-35) has been described as being performed by the transfer table 1. However, since the positioning can be performed by relative movement, the transfer table 1 is fixed and the thermocompression bonding tool is used together with the support table 5. The positioning adjustment may be performed by moving the fourth side.

In each of the first to third embodiments, the electronic component 3 (31 to 3) is provided on one terminal surface of the substrate 2a.
5) is temporarily press-bonded via a connecting member such as an anisotropic conductor,
The description is given on the assumption that the electronic component 3 (31 to 35) is fully bonded by the thermocompression bonding tool 4.

However, the substrates 2a, 2b of the liquid crystal display panel
In this case, the electronic component 3 is temporarily crimped on the terminal surfaces along the opposing edges on the same substrates 2a and 2b via a connecting member.

Therefore, although it takes time for the transport positioning operation, the thermocompression bonding tools 4 alternately face each other between the electronic components 3 temporarily crimped on the plurality of terminal surfaces on the same substrates 2a and 3a. Thus, even if the transfer table 1 or the thermocompression bonding tool 4 is conveyed or rotated in a direction perpendicular to the direction of the arrow X in FIG. In this way, it is possible to avoid the need for thermocompression bonding, thereby realizing the highly reliable mounting of the electronic component 3 with high reliability.

Further, in each of the above embodiments, five electronic components 3 are mounted on one terminal surface of the substrate 2a,
Thermocompression bonding tool 4 having pressing surface length L for two electronic components
In the application of the present invention, the number of electronic components on one terminal surface, the length of the pressed surface in the thermocompression tool, the number of presses by the thermocompression tool are described. Etc. are not limited to these numbers. For example, when eleven electronic components are mounted on one terminal surface and the thermocompression bonding tool has a pressing surface length of three electronic components, three electronic components are sequentially arranged twice from the right end side in the arrangement direction of the electronic components twice. After the pressing, the third pressing is performed on the three electronic components located on the left end side, and finally, the remaining two electronic components are pressed together with the sixth electronic component located on the left end side, After a total of four pressings, all the electronic components may be permanently mounted on one terminal surface of the substrate by pressure bonding.

In any case, according to the method of mounting an electronic component on a substrate according to the present invention, since a specific electronic component is not continuously subjected to thermocompression bonding, a local temperature rise of the substrate is avoided. Thus, high-quality and highly reliable mounting of electronic components can be realized without causing damage such as cracks and the like, and a remarkable effect can be obtained by applying the present invention to, for example, manufacturing of a liquid crystal display panel.

[0043]

According to the method of mounting an electronic component on a substrate according to the present invention, in assembling and manufacturing a liquid crystal display panel or the like, when mounting the electronic component on the substrate by thermocompression bonding, an unbalanced load or a local temperature rise. Therefore, it is possible to efficiently assemble and manufacture a highly reliable substrate, which is practically effective.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of a method for mounting an electronic component on a substrate according to the present invention.

FIG. 2A is a cross-sectional view taken along the line AA of FIG. 1 and FIG. 2B is a step subsequent to the electronic component mounting step shown in FIG. 2A. FIG. 2C is a cross-sectional view showing the next step of the electronic component mounting step.

FIGS. 3A to 3C are process diagrams showing a second embodiment of a method for mounting an electronic component on a substrate according to the present invention.

FIGS. 4A to 4C are process diagrams showing a third embodiment of a method for mounting an electronic component on a substrate according to the present invention.

FIG. 5 is a plan view showing a conventional method for mounting an electronic component on a substrate.

6 (a) is a cross-sectional view taken along line AA of FIG. 5 and FIG. 6 (b) is a step subsequent to the electronic component mounting step shown in FIG. 6 (a). FIG. 6C is a cross-sectional view showing a step subsequent to the electronic component mounting step.

FIG. 7 is a cross-sectional view showing one step in a conventional method for mounting an electronic component on another substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveying means 2a, 2b Substrate 3, 31-35 Electronic component 4 Thermocompression tool 5 Support base

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/32 H05K 3/32 CF term (Reference) 2H092 GA48 GA50 MA32 NA29 PA01 PA06 5E319 AB01 AC04 BB16 CC12 GG11 5F044 NN17 NN22 RR04 5G435 AA14 AA17 BB12 EE37 EE42 KK05 KK10

Claims (4)

[Claims] A mounting step of arranging and mounting a plurality of electronic components on a terminal surface of a substrate via a connecting member; and after the mounting step, the electronic components on the terminal surface are
In a method for mounting an electronic component on a substrate, comprising: a thermocompression bonding step in which a thermocompression bonding tool shifts a position and presses the electronic component. A method of mounting an electronic component on a substrate, wherein the electronic component is heated by being pressed against the substrate together with the component. 2. The thermocompression bonding tool has a pressing surface length L
Is 1/1 of the arrangement length D of the electronic components on one terminal surface of the substrate.
2. The method according to claim 1, wherein the electronic component has a length of less than 2. 3. The arrangement length D of the electronic component on one terminal surface of the substrate is a length obtained by multiplying the pressing surface length L of the thermocompression bonding tool by a plurality of times, and is less than the pressing surface length L. 2. The method for mounting an electronic component on a substrate according to claim 1, wherein the electronic component is formed to have an added length. 4. A pressing surface length L of the thermocompression bonding tool is a length corresponding to an arrangement length of at least two or more electronic components among the electronic components arranged on the substrate in the placing step. The method for mounting an electronic component on a substrate according to any one of claims 1 to 3, wherein the method is configured as follows.