JPH10173301A - Circuit board, wiring board, and method of manufacturing circuit board - Google Patents

Abstract

(57) Abstract: Wiring is performed around a position corresponding to a peripheral end surface of an anisotropic conductive member because wiring lines at positions corresponding to the peripheral end surface of an anisotropic conductive member have insufficient strength against thermal stress. The line could be broken. At each position where the peripheral end surface of the anisotropic conductive member and the wiring line intersect, the length of the peripheral end surface of the anisotropic conductive member crossing the wiring line is apparently longer than the line width of the wiring line. I made it. This makes it possible to improve the strength against the thermal stress of the wiring line at a position corresponding to the peripheral end face of the anisotropic conductive member without increasing the line width of the wiring line. Breakage of the wiring line around the corresponding position can be prevented. Thus, a circuit board, a wiring board, and a method of manufacturing a circuit board that can improve reliability can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Table of Contents] The present invention will be described in the following order. TECHNICAL FIELD The prior art (FIGS. 15 and 16) Problems to be Solved by the Invention Means for Solving the Problems Embodiments of the Invention (FIGS. 1 to 14) (1) First Embodiment (FIG. 1 to 3) (2) Second embodiment (FIGS. 4 and 5) (3) Third embodiment (FIGS. 6 to 8) (4) Other embodiments (FIGS. 9 to 14) Effects of the Invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board, a wiring board, and a method of manufacturing a circuit board, and more particularly, to a circuit board having electronic components mounted on the wiring board via an anisotropic conductive member, and a method of manufacturing the circuit board. It is suitable to be applied to. It is also suitable for application to a wiring board on which electronic components are mounted via an anisotropic conductive member.

[0003]

2. Description of the Related Art Heretofore, there has been used a semiconductor chip mounted on a printed wiring board via an anisotropic conductive film as a bare chip by flip chip mounting. FIG. 15 shows an example of a circuit board in which a semiconductor chip is mounted on a printed wiring board via an anisotropic conductive film in a bare chip by flip-chip mounting.

The circuit board 1 has a bonding surface 2 of a semiconductor chip 2.
Each solder bump 4 formed on an aluminum electrode (hereinafter referred to as a pad) 3 disposed at a predetermined pitch along the peripheral portion of A is printed wiring lines through an anisotropic conductive film 5. The semiconductor chip 2 is mounted on the printed wiring board 6 by joining one surface (hereinafter referred to as a mounting surface) 6A of the substrate 6 to the corresponding lands 7 provided corresponding to the pads 3 respectively. It is configured to be mechanically and electrically connected.

In practice, the circuit board 1 is manufactured by the following procedure. That is, first, a wiring line 8 for forming a predetermined conductor pattern and each pad 3 of the semiconductor chip 2 are formed.
After the printed wiring board 6 in which the lands 7 are formed on the mounting surface 6A in correspondence with the above, each of the lands 7 disposed on the printed wiring board 6 is covered (a size larger than that of the semiconductor chip 2). A rectangular anisotropic conductive film 5 having a slightly larger size is temporarily attached to the mounting surface 6A of the printed wiring board 6 at a temperature equal to or lower than the glass transition temperature of the anisotropic conductive film 5.

Subsequently, the bonding surface 2A of the semiconductor chip 2 is opposed to the mounting surface 6A of the printed wiring board 6, and the semiconductor chip 2 is positioned and mounted on the anisotropic conductive film 5, and then the semiconductor chip 2 is subjected to a predetermined thermocompression bonding. Thermocompression bonding is performed on the anisotropic conductive film 5 under the conditions. Thereby, each solder bump 4 of the semiconductor chip 2 and each corresponding land 7 of the printed wiring board 6 are electrically connected via conductive particles (not shown) existing in the anisotropic conductive film 5, Thus, the semiconductor chip 2 is mechanically and electrically connected to the mounting surface 6A of the printed wiring board 6.

[0007]

By the way, in an electronic device on which the circuit board 1 manufactured as described above is mounted, when the electronic device is used, the printed wiring board 6
Since the semiconductor chip 2 mounted on the device generates heat,
The semiconductor chip 2 and the printed wiring board 6 expand. Therefore, a temperature change occurs inside the electronic device when the electronic device is used and when it is not used. As a result, in the circuit board 1, the semiconductor chip 2 and the printed circuit board 6 repeat expansion and contraction.

However, since the thermal expansion coefficient of the printed wiring board 6 is usually larger than that of the semiconductor chip 2 and the anisotropic conductive film 5, the printed wiring board 6 has a stress distortion due to the difference in the thermal expansion coefficient. Occur. In this case, among the wiring lines 8 formed on the printed wiring board 6, the anisotropic conductive film 5
In the position corresponding to the peripheral end face 5A, the influence of the difference in the thermal expansion coefficient (that is, the influence of the difference in the contraction rate between the anisotropic conductive film 5 and the printed wiring board 6) is the most affected. Accordingly, the wiring line 8 at the position corresponding to the peripheral end face 5A of the anisotropic conductive film 5 is most subjected to thermal stress due to the difference in the coefficient of thermal expansion. As a result, as shown in FIG. Accordingly, the wiring line 8 around the position corresponding to the peripheral end face 5A of the anisotropic conductive film 5 may be broken.

As one method for solving such a problem, it is conceivable to increase the line width of the wiring line 8. However, when the line width of the wiring line 8 is increased,
There is a problem that the mounting density of the circuit board 1 is reduced.

Accordingly, without increasing the line width of the wiring line 8, the strength of the wiring line 8 at the position corresponding to the peripheral end face 5A of the anisotropic conductive film 5 can be improved with respect to the thermal stress, or If the thermal stress applied to the wiring line 8 at the position corresponding to the peripheral end surface 5A of the anisotropic conductive film 5 can be reduced without reducing the mounting density of the circuit board 1, the position corresponding to the peripheral end surface 5A of the anisotropic conductive film 5 can be reduced. Can be prevented from being broken,
It is considered that the reliability of the circuit board 1 can be further improved.

The present invention has been made in view of the above points, and an object of the present invention is to propose a circuit board, a wiring board, and a method of manufacturing a circuit board which can improve reliability.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, at each position where the peripheral end face of the anisotropic conductive member intersects with the wiring line, the peripheral end face of the anisotropic conductive member is connected to the wiring line. Is apparently longer than the line width of the wiring line. According to the present invention,
The strength of the wiring line at a position corresponding to the peripheral end surface of the anisotropic conductive member can be improved without increasing the line width of the wiring line against thermal stress.

Further, in the present invention, the thickness of a region corresponding to at least each position where the wiring line formed on the wiring board and the peripheral end of the anisotropic conductive member intersect is determined by setting the thickness of the wiring line and the anisotropic conductive member. The electrode portions of the electronic component correspond to the wiring board via the anisotropic conductive member formed so as to be thinner than the region other than the region corresponding to each position where the peripheral end of the member intersects. The electronic component and the wiring board were integrally held together with the land. ADVANTAGE OF THE INVENTION According to this invention, the thermal stress with respect to the wiring line in the position corresponding to the peripheral end part of an anisotropic conductive member can be reduced.

Further, according to the present invention, a wiring board having a wiring line for forming a predetermined conductor pattern and a land formed on one surface corresponding to an electrode portion of an electronic component is manufactured. The thickness of the region corresponding to each position where the wiring line intersects with the peripheral end of the anisotropic conductive member is the region corresponding to each position where the wiring line intersects with the peripheral end of the anisotropic conductive member. After temporarily attaching an anisotropic conductive member that is thinner than the thickness in the other area to one surface of the wiring board so as to cover the land, and positioning and mounting the electrode part of the electronic component on the corresponding land of the wiring board The electronic component was thermocompression bonded to the anisotropic conductive film. ADVANTAGE OF THE INVENTION According to this invention, the thermal stress with respect to the wiring line in the position corresponding to the peripheral end part of an anisotropic conductive member can be reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

(1) First Embodiment In FIG. 1, reference numeral 10 denotes a circuit board as a whole. The circuit board 10 is mounted on a plurality of pads 12 formed as electrodes on a bonding surface 11A of a semiconductor chip 11. The bump 13 formed as an electrode portion is
And electrically connected to corresponding lands 16 disposed on one surface (hereinafter referred to as a mounting surface) 15A of the printed wiring board 15 in correspondence with the pads 12 of the semiconductor chip 11 respectively. By doing so, the semiconductor chip 1
1 is mechanically and electrically connected to the printed wiring board 15.

In the case of the first embodiment, as shown in FIGS. 1 and 2, the anisotropic conductive film 14 forms each pad 12 of the semiconductor chip 11 and each corresponding land 16 of the printed wiring board 15 respectively. It has a size to cover, and its peripheral end surface 14A is formed in a corrugated shape. Thus, the peripheral end surface 14A of the anisotropic conductive film 14 crosses each wiring line 17 forming the conductor pattern drawn on the mounting surface 15A of the printed wiring board 15 at an angle other than a right angle.

In practice, the circuit board 10 can be manufactured by the procedure described below. That is, first, a wiring line 17 for forming a predetermined conductor pattern is formed.
And a printed wiring board 15 having a land 16 disposed on a mounting surface 15A corresponding to each pad 12 of the semiconductor chip 11, and then a surface 15B of the printed wiring board 15 facing the mounting surface 15A is fixed. The mounting surface 15 of the printed wiring board 15 is supported by the supporting device
A is temporarily attached to A at a temperature equal to or lower than the glass transition temperature of the anisotropic conductive film 14 so as to cover each land 16.

Subsequently, the surface 11B of the semiconductor chip 11 facing the bonding surface 11A is sucked by a predetermined suction device, so that the bonding surface 11A of the semiconductor chip 11 faces the mounting surface 15A of the printed wiring board 15, and After the semiconductor chip 11 is positioned and mounted on the anisotropic conductive film 14, the semiconductor chip 11 is thermocompression-bonded to the anisotropic conductive film 14 under a predetermined thermocompression condition using a tool having a heating head. Each pad 12 of the anisotropic conductive film 1
4 to electrically connect to the corresponding lands 16 of the wiring board 15. Thereby, the circuit board 10 can be obtained.

In the above configuration, in the circuit board 10, the peripheral end surface 14A of the anisotropic conductive film 14 is formed in a corrugated shape so that the peripheral end surface 14A of the anisotropic conductive film 14
7 at an angle other than a right angle, the peripheral end face 14A of the anisotropic conductive film 14 is connected to each wiring line 17 at each position where the peripheral end face 14A of the anisotropic conductive film 14 and each wiring line 17 intersect. At 17 each wiring line 1
7 can be apparently longer than the line width of the wiring line 17.

That is, as shown in FIG. 3, since the peripheral end face 14A of the anisotropic conductive film 14 is formed in a corrugated shape,
The peripheral end surface 14A of the anisotropic conductive film 14 intersects each wiring line 17 at a certain angle other than a right angle. Accordingly, the length L1 of the peripheral end surface 14A of the anisotropic conductive film 14 crossing each wiring line 17 in each wiring line 17 is apparently longer than the line width W1 of each wiring line 17.

Therefore, in the circuit board 10, the strength of the wiring line 17 at the position corresponding to the peripheral end face 14A of the anisotropic conductive film 14 can be improved with respect to the thermal stress. Breaking of each wiring line 17 around the position corresponding to the end face 14A can be prevented.

According to the above configuration, the peripheral end surface 14 of the anisotropic conductive film 14 is formed in a wavy shape so that the peripheral end surface 14A of the anisotropic conductive film 14 crosses each wiring line 17 at an angle other than a right angle. The peripheral end surface 1 of the anisotropic conductive film 14
Since the strength against the thermal stress of the wiring line 17 at the position corresponding to 4A can be improved, it is possible to prevent each wiring line 17 around the position corresponding to the peripheral end surface 14A of the anisotropic conductive film 14 from being broken. Can be. Thus, the circuit board 10 that can improve the reliability can be realized.

Further, according to the above configuration, the wiring line 17
Without increasing the line width, the strength of the wiring line 17 at a position corresponding to the peripheral end surface 14A of the anisotropic conductive film 14 can be improved with respect to thermal stress, thereby reducing the mounting density of the circuit board 10. Without circuit board 10
Can be improved in reliability.

(2) Second Embodiment In FIG. 4, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, reference numeral 20 denotes a printed wiring board as a whole. The wiring lines 21 to be formed and the lands 22 corresponding to the pads 12 of the semiconductor chip 11 are made of an insulating substrate formed on the mounting surface 20A, and the pads 12 of the semiconductor chip 11 are formed.
The semiconductor chip 11 is mounted such that the semiconductor chip 11 is bonded to the corresponding land 22 of the printed wiring board 20 via the rectangular anisotropic conductive film 23.

In the case of the second embodiment, as shown in FIGS. 4 and 5, each wiring line 21 is located at a position where the peripheral end face 23A of the anisotropic conductive film 23 intersects with each wiring line 21. The corresponding region 21A is formed in a rectangular shape and is formed thicker than the other region in each wiring line 21, so that each wiring pattern 21 intersects with the peripheral end surface 23A of the anisotropic conductive film 23. The length L2 of the peripheral end surface 23A of the anisotropic conductive film 23 crossing each wiring line 21 in each wiring line 21 is apparently longer than the line width W2 of the wiring line 21 at the position.

In the above configuration, in the printed wiring board 20, each region 21A of each wiring line 21 corresponding to each position where the peripheral end surface 23A of the anisotropic conductive film 23 intersects with each wiring line 21 is rectangular. Since it is formed in a shape and is formed thicker than the other region in each wiring line 21, the anisotropic conductive film is formed at each position where the peripheral end face 23 </ b> A of the anisotropic conductive film 23 intersects with each wiring line 21. The length L2 of the peripheral end surface 23A of the film 23 crossing each wiring line 21 in each wiring line 21 can be apparently longer than the line width W2 of the wiring line 21.

Accordingly, in the printed wiring board 20, the strength of each wiring line 21 at a position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23 can be improved with respect to thermal stress. Peripheral end surface 23A
Can be prevented from being broken in the vicinity of the position corresponding to.

According to the above configuration, each region 21A of each wiring line 21 corresponding to each position where the peripheral end face 23A of the anisotropic conductive film 23 intersects each wiring line 21 is formed in a rectangular shape. Since each wiring line 21 is formed thicker than other regions, the anisotropic conductive film 2 is formed.
Since the strength of each wiring line 21 at the position corresponding to the peripheral end face 23A of the third anisotropic conductive film 23 can be improved, the wiring lines 21 around the position corresponding to the peripheral end face 23A of the anisotropic conductive film 23 are broken. Can be prevented. Thus, the wiring board 20 that can improve the reliability can be realized.

According to the above configuration, the wiring line 21
Of the wiring lines 21 at positions corresponding to the peripheral end surface 23A of the anisotropic conductive film 23 can be improved without increasing the line width of the anisotropic conductive film 23, thereby lowering the mounting density of the printed wiring board 20. Without this, the reliability of the printed wiring board 20 can be improved.

(3) Third Embodiment In FIG. 6, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, reference numeral 30 denotes a circuit board as a whole.
0 indicates that the bumps 13 formed on the pads 12 formed on the bonding surface 11A of the semiconductor chip 11 correspond to the pads 12 of the semiconductor chip 11 via the anisotropic conductive film 31, respectively. The semiconductor chip 11 is mechanically and electrically connected to the printed wiring board 15 by being electrically connected to the corresponding lands 16 provided on the mounting surface 15A of the printed wiring board 15.

In the case of the third embodiment, the anisotropic conductive film 31
The semiconductor chip 11 is formed so that the thickness thereof gradually decreases as it approaches the peripheral end portion 31A of the anisotropic conductive film 31 from a region corresponding to the peripheral end surface 11C of the semiconductor chip 11. Accordingly, the thickness of the region corresponding to each position where the peripheral end 31A of the anisotropic conductive film 31 intersects with each wiring line 17 is equal to the region of the anisotropic conductive film 31 facing the bonding surface 11A of the semiconductor chip 11. Thinner than the thickness of the anisotropic conductive film 3
The thermal stress on each of the wiring lines 17 at each position where the peripheral end portion 31A of each of the first and second wiring lines 17 intersect can be reduced.

In practice, the circuit board 30 can be manufactured by the procedure described below. That is, first, a wiring line 17 for forming a predetermined conductor pattern is formed.
Then, a printed wiring board 15 having lands 16 disposed on a mounting surface 15A corresponding to each pad 12 of the semiconductor chip 11 is manufactured. Subsequently, in a state where the surface 15B of the printed wiring board 15 facing the mounting surface 15A is supported by a predetermined supporting device, the anisotropic conductive film 31 whose peripheral portion is formed in a saw shape as shown in FIG. Is temporarily attached to the mounting surface 15A of the printed wiring board 15 at a temperature equal to or lower than the glass transition temperature of the anisotropic conductive film 31 'so as to cover each land 16.

Subsequently, the surface 11B of the semiconductor chip 11 facing the bonding surface 11A is sucked by a predetermined suction device, so that the bonding surface 11A of the semiconductor chip 11 faces the mounting surface 15A of the printed wiring board 15, and After the semiconductor chip 11 is positioned and mounted on the anisotropic conductive film 31 ', the semiconductor chip 11 is thermocompression-bonded to the anisotropic conductive film 31' under a predetermined thermocompression bonding condition using a tool having a heating head. Each pad 12 of the chip 11 is bonded to each corresponding land 16 of the printed wiring board 15 via the anisotropic conductive film 31.

Here, the mounting surface 15 of the printed wiring board 15
A state in which an anisotropic conductive film 31 ′ is temporarily attached to A (FIG. 8).
(A), the semiconductor chip 11 is replaced with an anisotropic conductive film 31 '.
When thermocompression bonding is performed on the semiconductor chip 11, the bonding surface 11
Since the region of the anisotropic conductive film 31 'opposite to A is pressed, a part of the anisotropic conductive film 31' is formed by the saw portions 31'A and 31'A of the anisotropic conductive film 31 '. When the thermocompression bonding is finally completed and the anisotropic conductive film 31 'is hardened, the peripheral portion 31A is formed in a substantially corrugated shape. 31 (FIG. 8C).

In this case, the thickness of the anisotropic conductive film 31 'is
Anisotropic conductive film 3 is formed on mounting surface 15A of printed wiring board 15.
In the state where 1 'is temporarily attached (FIG. 8D), the thickness is substantially uniform, but when pressure is applied to the anisotropic conductive film 31', a part of the anisotropic conductive film 31 'is formed. Is anisotropic conductive film 3
1 'gradually flows between the saw portion 31' and the saw portion 31 ', so that the anisotropic conductive film 31' has a peripheral end face 1 of the semiconductor chip.
An inclination is formed from the region corresponding to 1C to the peripheral portion (FIG. 8 (E)). When the thermocompression bonding is finally completed and the anisotropic conductive film 31 'is cured, the peripheral end surface of the semiconductor chip 11 is formed. An anisotropic conductive film 31 is formed in which the thickness gradually decreases as approaching the peripheral end 31A from the region corresponding to 11C (FIG. 8F).

In the above configuration, in the circuit board 30, the anisotropic conductive film 31 is formed on the peripheral end face 1 of the semiconductor chip 11.
1C, the thickness is gradually reduced as approaching the peripheral end 31A from the region corresponding to 1C, so that the peripheral edge 31A of the anisotropic conductive film 31 intersects with each wiring line 17 Thermal stress on each wiring line 17 can be reduced.

Therefore, in the circuit board 30, the thermal stress on each wiring line 17 at each position where the peripheral end 31A of the anisotropic conductive film 31 intersects with each wiring line 17 can be reduced. Anisotropic conductive film 31
Of each wiring line 17 around the position corresponding to the peripheral portion 31A can be avoided.

According to the above configuration, the anisotropic conductive film 31 ′ whose peripheral portion is formed in a saw shape is temporarily attached to the mounting surface 15 A of the printed wiring board 15 so as to cover each land 16, and the semiconductor chip is formed. After the bumps 13 of the semiconductor chip 11 are positioned and mounted on the corresponding lands 16 of the printed wiring board 15, the semiconductor chip 11 is thermocompression-bonded to the anisotropic conductive film 31 'under predetermined thermocompression bonding conditions. Since the anisotropic conductive film 31 can be formed such that its thickness gradually decreases as it approaches the peripheral end 31A from the region corresponding to the peripheral end surface 11C.
Can be reduced at each position where the peripheral portion 31A of the anisotropic conductive film 31 intersects with each of the wiring lines 17, whereby each of the peripheral portions 31A of the anisotropic conductive film 31 around the position corresponding to the peripheral portion 31A can be reduced. Breakage of the wiring line 17 can be avoided. Thus, the circuit board 30 and the method for manufacturing the circuit board 30 that can improve the reliability can be realized.

Further, according to the above configuration, the anisotropic conductive film 3
1 is formed in a corrugated shape, the peripheral edge 31A of the anisotropic conductive film 31 is located at each position where the peripheral edge 31A of the anisotropic conductive film 31 and each wiring line 17 intersect. Are each wiring line 1 in each wiring line 17.
7 can be longer than the line width of the wiring line 17. Accordingly, the strength of each wiring line 17 at the position corresponding to the peripheral end 31A of the anisotropic conductive film 31 can be improved, so that the position corresponding to the peripheral end 31A of the anisotropic conductive film 31 can be improved. Breakage of each wiring line 17 in the periphery can be further prevented.

(4) Other Embodiments In the above-described first embodiment, the peripheral end surface 14A of the anisotropic conductive film 14 is formed in a corrugated shape so that the peripheral end surface 14A of the anisotropic conductive film 14 is formed. Although the case where the strength against the thermal stress of each wiring line 17 at the corresponding position is improved has been described, the present invention is not limited to this, and FIG.
As shown in FIG.
The semiconductor chip 11 is joined to the corresponding lands 16 of the printed wiring board 15 via the anisotropic conductive film 23 with the semiconductor chip 11 crossing the wiring line 17 at an angle of 45 °. 11 and printed wiring board 1
5 can be obtained as the same effect as in the above-described embodiment.

In practice, the circuit board 40 shown in FIG. 9 can be manufactured by the procedure described below. That is, first, a bump 13 is formed on each pad 12 of the semiconductor chip 11 and a printed wiring board 15 is formed. Then, the surface 15B of the printed wiring board 15 facing the mounting surface 15A is fixed by a predetermined supporting device. In a state where the lands 16 are supported, an anisotropic conductive film 23 is temporarily attached to the mounting surface 15A of the printed wiring board 15 so as to cover each land 16. In this case, as shown in FIG. 10, the anisotropic conductive film 23 is mounted on the mounting surface 15 of the printed wiring board 15 so that the peripheral end surface 23A of the anisotropic conductive film 23 intersects the wiring line 17 at an angle of 45 °.
Temporarily attach to A.

Subsequently, the surface 11B of the semiconductor chip 11 facing the bonding surface 11A is sucked by a predetermined suction device, so that the bonding surface 11A of the semiconductor chip 11 faces the mounting surface 15A of the printed wiring board 15, and After the semiconductor chip 11 is positioned and mounted on the anisotropic conductive film 23, the semiconductor chip 11 is thermocompression-bonded to the anisotropic conductive film 23 under a predetermined thermocompression bonding condition using a tool having a heating head. Each pad 12 of the anisotropic conductive film 2
3 correspond to each land 1 of the printed wiring board 15.
6 Thereby, the circuit board 40 can be obtained.

In the above configuration, in the circuit board 40, since the peripheral end face 23A of the anisotropic conductive film 23 intersects the wiring line 17 at an angle of 45 °, the anisotropic conductive film 23
The length at which the peripheral end surface 23A of the anisotropic conductive film 23 crosses each wiring line 17 at each position where the peripheral end surface 23A intersects with each wiring line 17 is apparent from the line width of the wiring line 17. Can be longer.

Accordingly, in the circuit board 40, the strength of each wiring line 17 at a position corresponding to the peripheral end face 23A of the anisotropic conductive film 23 can be improved with respect to the thermal stress. Breaking of each wiring line 17 around the position corresponding to the peripheral end face 23A can be prevented.

According to the above configuration, the anisotropic conductive film 23 is mounted on the mounting surface 15A of the printed wiring board 15 so that the peripheral end surface 23A of the anisotropic conductive film 23 intersects the wiring line 17 at an angle of 45 °. After the temporary attachment, the semiconductor chip 11 is thermocompression-bonded to the anisotropic conductive film 23 to improve the strength of each wiring line 17 at a position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23 against thermal stress. Therefore, it is possible to prevent each wiring line 17 from being broken around the position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23. Thus, the circuit board 40 that can improve the reliability can be realized.

In the above-described second embodiment, each region 21A of each wiring line 21 corresponding to each position where the peripheral end surface 23A of the anisotropic conductive film 23 intersects each wiring line 21 is formed in a rectangular shape. Forming each wiring line 2
1, the case where the strength against the thermal stress of the wiring line 21 at the position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23 is improved by forming the region thicker than the other region, 11A and FIG. 11B in which the same reference numerals are given to the corresponding parts in FIG. 4, for example, the peripheral end face 23A of the anisotropic conductive film 23 and each wiring line 21 Each area 21A corresponding to each intersecting position is formed in a polygonal shape so as to be thicker than other areas in each wiring line 21, or as shown in FIGS. 12A and 12B, Each region 21A of each wiring line 21 corresponding to each position where the peripheral end surface 23A of the anisotropic conductive film 23 intersects with each wiring line 21 is formed in a substantially arc shape to form another region in each wiring line 21. The area may be formed to be thicker than the area. In short, each area 21A corresponding to each position where the peripheral end face 23A of the anisotropic conductive film 23 intersects with each wiring line 21 is added to each other in each wiring line 21. If the region is formed thicker than the region, various other shapes can be applied as the shape of the region 21A.

That is, the peripheral end surface 14 A of the anisotropic conductive film 14
The peripheral end face 14 </ b> A of the anisotropic conductive film 14 is
In each of the wiring lines 2, the length traversing each wiring line 21 is apparently longer than the line width of the wiring line 21.
1 may be formed.

Further, a printed wiring board 50 as shown in FIG. 13 in which the same reference numerals are given to portions corresponding to those in FIG. 4 may be manufactured. That is, the printed wiring board 50 is an insulating substrate in which wiring lines 51 for forming a predetermined conductor pattern and lands 52 respectively corresponding to the pads 12 of the semiconductor chip 11 are formed on the mounting surface 50A. The semiconductor chip 11 is mounted such that each pad 12 is bonded to the corresponding land 52 of the printed wiring board 50 via the anisotropic conductive film 23.

In the case of this printed wiring board 50, FIG.
As shown in FIG. 14, each wiring line 51 intersects the peripheral end surface 23A of the anisotropic conductive film 23 at an angle of approximately 45 ° at a position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23. Are formed on the mounting surface 50A of the printed wiring board 50, so that each wiring pattern 51 intersects with the peripheral end surface 23A of the anisotropic conductive film 23,
The length of the peripheral end surface 23A of the anisotropic conductive film 23 crossing each wiring line 51 in each wiring line 51 is determined by the length of the wiring line 51.
It is designed to be apparently longer than the line width.

In the above configuration, in the printed wiring board 50, each wiring line 51 is located at a position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23.
3 is formed on the mounting surface 50A of the printed wiring board 50 so as to intersect the lower end side 23B of the peripheral end surface 23A at an angle of 45 °, so that the peripheral end surface 23A of the anisotropic conductive film 23 is formed.
The length at which the peripheral end face 23A of the anisotropic conductive film 23 crosses each wiring line 51 in each wiring line 51 at a position where the wiring line 51 intersects with the wiring line 51 can be apparently longer than the line width of the wiring line 21. .

Therefore, in the printed wiring board 50, the strength of each wiring line 51 at a position corresponding to the peripheral end face 23A of the anisotropic conductive film 23 can be improved with respect to the thermal stress. Peripheral end surface 23A
Can be prevented from being broken around each of the wiring lines 51 around the position corresponding to.

According to the above configuration, the anisotropic conductive film 2 is located at a position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23.
3 is formed on the mounting surface 50A of the printed wiring board 50 so as to intersect with the peripheral end surface 23A of the third at an angle of 45 °. Since the strength of the wiring line 51 against thermal stress can be improved, it is possible to prevent the wiring lines 51 around the position corresponding to the peripheral end surface 23A of the anisotropic conductive film 23 from being broken.
Thus, a printed wiring board 50 that can improve reliability can be realized.

Here, in the case of the printed wiring board 50, at a position corresponding to the peripheral end face 23A of the anisotropic conductive film 23,
Each wiring line 51 is formed on the mounting surface 50A of the printed wiring board 50 so as to intersect with the peripheral end surface 23A of the anisotropic conductive film 23 at an angle of 45 °.
At the position corresponding to 3A, each wiring line 51 may be formed so as to intersect the peripheral end surface 23A of the anisotropic conductive film 23 at every other angle than a right angle. That is, at the position where the peripheral end surface 23A of the anisotropic conductive film 23 and each wiring line 51 intersect, the peripheral end surface 23A of the anisotropic conductive film 23 is
In 1, each wiring line 51 may be formed such that the length crossing each wiring line 51 is apparently longer than the line width of the wiring line 51.

Further, in the above-described first embodiment, the peripheral end surface 14A of the anisotropic conductive film 14 is formed in a corrugated shape, so that the wiring line 17 at a position corresponding to the peripheral end surface 14A of the anisotropic conductive film 14 is formed. However, the present invention is not limited to this. For example, the anisotropic conductive film 14 may be formed in a circular shape or the peripheral end surface 14A of the anisotropic conductive film 14 may be formed. In short, the pads 12 of the semiconductor chip 11 are electrically connected to the corresponding lands 16 of the printed wiring board 15, and the semiconductor chip 11 and the printed wiring board 15 are formed.
And the peripheral end surface 14 of the anisotropic conductive film 14.
If the strength of the wiring line 17 at the position corresponding to A can be improved with respect to thermal stress, various other shapes can be applied as the anisotropic conductive film 14.

Further, in the third embodiment described above, the peripheral portion 31A approaches the peripheral portion 31A from the region corresponding to the peripheral end surface 11C of the semiconductor chip 11 by using the anisotropic conductive film 31 'whose peripheral portion is formed in a saw-like shape. The anisotropic conductive film 31 is formed such that the thickness gradually decreases in accordance with the above-described process, so that each wiring line at each position where the peripheral end portion 31A of the anisotropic conductive film 31 intersects with each wiring line 17 is formed. Although the case where the thermal stress on the substrate 17 is reduced has been described, the present invention is not limited to this, and at least the region corresponding to the position where the wiring line 17 intersects with the peripheral end portion 31A of the anisotropic conductive film 31 at the time of thermal compression. Is thicker than the wiring line 17 and the anisotropic conductive film 3
If it can be formed thinner than the region other than the region corresponding to the position where the peripheral end portion 31A intersects with the peripheral end portion 31A, the shape of the anisotropic conductive film 31 'when temporarily attached to the mounting surface 15A of the printed wiring board 15 is obtained. In addition, anisotropic conductive films 31 'having various shapes can be applied.

[0057]

As described above, according to the present invention, the length at which the peripheral end surface of the anisotropic conductive member crosses the wiring line at the position where the peripheral end surface of the anisotropic conductive member intersects with the wiring line of the wiring board. By making the line width apparently longer than the line width of the wiring line, it is possible to improve the strength against thermal stress of the wiring line at a position corresponding to the peripheral end surface of the anisotropic conductive member without increasing the line width of the wiring line. So you can
Breakage of the wiring line at a position corresponding to the peripheral end surface of the anisotropic conductive member can be prevented. Thus, a circuit board and a wiring board that can improve reliability can be realized.

According to the present invention, at least the thickness of the region corresponding to each position where the wiring line formed on the wiring board and the peripheral end of the anisotropic conductive member intersect is determined by setting the thickness of the wiring line to the anisotropic conductive member. It is formed thinner than the area other than the area corresponding to each position where the peripheral end of the conductive member intersects, and the electrodes of the electronic component are joined to the corresponding lands of the wiring board, and the electronic component and the wiring board are integrated. By holding the anisotropic conductive member, thermal stress on the wiring line at a position corresponding to the peripheral end of the anisotropic conductive member can be reduced. Breaking can be prevented. Thus, a circuit board that can improve reliability can be realized.

Further, according to the present invention, a wiring board having a wiring line for forming a predetermined conductor pattern and a land formed on one surface corresponding to an electrode of an electronic component is manufactured.
At the time of thermocompression bonding, at least the thickness of the region corresponding to each position where the wiring line intersects with the peripheral end of the anisotropic conductive member is the thickness of each region where the wiring line intersects with the peripheral end of the anisotropic conductive member. An anisotropic conductive member having a shape that is thinner than the thickness in a region other than the region corresponding to the position is temporarily attached to one surface of the wiring board so as to cover the land, and the electrode part of the electronic component is attached to the wiring substrate. After positioning and mounting on the corresponding land, the electronic component is thermocompression bonded to the anisotropic conductive film to reduce the thermal stress on the wiring line at the position corresponding to the peripheral end of the anisotropic conductive member. Therefore, it is possible to prevent the wiring line at the position corresponding to the peripheral end of the anisotropic conductive member from being broken. Thus, a method for manufacturing a circuit board that can improve reliability can be realized.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing one embodiment of a circuit board according to the present invention.

FIG. 2 is a schematic top view for explaining a configuration of an anisotropic conductive film.

FIG. 3 is a schematic top view for explaining a relationship between a peripheral end surface of an anisotropic conductive film and a wiring pattern;

FIG. 4 is a schematic perspective view showing one embodiment of a printed wiring board according to the present invention.

FIG. 5 is a schematic diagram for explaining the shape of a wiring line;

FIG. 6 is a schematic sectional view showing an embodiment of a circuit board according to the present invention.

FIG. 7 is a schematic top view for explaining the configuration of an anisotropic conductive film.

FIGS. 8A to 8C are schematic diagrams (A), (B), and (C) and schematic cross-sectional diagrams (D), (E), and (F) for explaining changes in the shape and thickness of an anisotropic conductive film. It is.

FIG. 9 is a partially cutaway perspective view showing a configuration of a circuit board according to another embodiment.

FIG. 10 is a schematic top view for explaining a positional relationship between an anisotropic conductive film and a wiring line according to another embodiment.

11A and 11B are a schematic diagram (A) and a schematic perspective view (B) for describing the shape of a wiring pattern according to another embodiment.

12A and 12B are a schematic diagram (A) and a schematic perspective view (B) for describing the shape of a wiring pattern according to another embodiment.

FIG. 13 is a partially cutaway perspective view showing a configuration of a circuit board according to another embodiment.

FIG. 14 is a schematic diagram for explaining a positional relationship between an anisotropic conductive film and a wiring line in a circuit board according to another embodiment.

FIG. 15 is a partially cutaway perspective view showing an example of the configuration of a conventional circuit board.

FIG. 16 is a schematic perspective view for explaining a break of a wiring line;

[Explanation of symbols]

10, 30, 40, 50: circuit board, 11: semiconductor chip, 12: pad, 13: bump, 14, 23,
31, 31 '... anisotropic conductive film, 14A, 23A ... peripheral end face of anisotropic conductive film, 15, 20 ... printed wiring board, 16, 52 ... land, 17, 51 ... wiring line.

Claims (13)

[Claims] An electronic component, a wiring board for forming a predetermined conductor pattern, and a wiring board having a land corresponding to an electrode portion of the electronic component formed on one surface; and the electrode portion of the electronic component, A circuit board comprising an anisotropic conductive member that is joined to the corresponding land of the wiring board and integrally holds the electronic component and the wiring board, wherein a peripheral end surface of the anisotropic conductive member and the wiring line A circuit board characterized in that the length at which the peripheral end face of the anisotropic conductive member intersects the wiring line is apparently longer than the line width of the wiring line at each position where the crossing is made. 2. The anisotropic conductive member, wherein the peripheral end face of the anisotropic conductive member crosses the wiring line at each position where the peripheral end face of the anisotropic conductive member intersects with the wiring line. 2. The circuit board according to claim 1, further comprising the peripheral end surface having a shape such that a length is apparently longer than a line width of the wiring line. 3. The circuit board according to claim 2, wherein the anisotropic conductive member has the peripheral end face formed in a corrugated shape. 4. The anisotropic conductive member, wherein the electrode portion of the electronic component is joined to the corresponding land of the insulating substrate such that the peripheral end surface intersects the wiring line at an angle other than a right angle. The circuit board according to claim 1, wherein the electronic component and the insulating substrate are integrally held. 5. The anisotropic conductive member has a rectangular shape.
The electrode part of the electronic component is joined to the corresponding land of the insulating substrate so that the peripheral end surface intersects the wiring line at an angle of 45 °, and the electronic component and the insulating substrate are integrally formed. 5. The method according to claim 4, wherein
A circuit board according to claim 1. 6. A wiring board having an electronic component, a wiring line for forming a predetermined conductor pattern, and a land corresponding to an electrode portion of the electronic component formed on one surface, at least the wiring line and a peripheral end portion. The thickness of the region corresponding to each of the intersections is formed to be thinner than the thickness of the region other than the region corresponding to each of the positions where the wiring line and the peripheral end intersect with each other. A circuit board, comprising: an anisotropic conductive member that joins an electrode portion to a corresponding one of the lands of the wiring board and integrally holds the electronic component and the wiring board. 7. The anisotropic conductive member is formed so as to gradually decrease in thickness from a region corresponding to a peripheral end surface of the electronic component toward the peripheral end of the anisotropic conductive member. The circuit board according to claim 6, wherein: 8. An insulating substrate in which a wiring line for forming a predetermined conductor pattern and lands respectively corresponding to electrode portions formed on a joint surface of the electronic component are formed on one surface. In a wiring board on which the electronic component is mounted by joining the electrode portion to the corresponding land of the insulating substrate via an anisotropic conductive member, a peripheral end surface of the anisotropic conductive member and the wiring line Wherein the length at which the peripheral end face of the anisotropic conductive member traverses the wiring line at each position where the wiring line intersects the wiring line is apparently longer than the line width of the wiring line. Wiring board. 9. The wiring line, wherein the line width of a region corresponding to each position where the peripheral end face of the anisotropic conductive member intersects with the wiring line has a line width of the peripheral end face of the anisotropic conductive member. 9. The wiring board according to claim 8, wherein the wiring board is formed thicker than a line width in a region other than the region corresponding to each position where the wiring line intersects with the wiring line. 10. The insulating substrate according to claim 1, wherein said wiring line intersects said peripheral end surface of said anisotropic conductive member at an angle other than a right angle at a position corresponding to said peripheral end surface of said anisotropic conductive member. The wiring board according to claim 8, wherein the wiring board is formed on the one surface. 11. The insulating substrate according to claim 1, wherein the wiring line intersects the peripheral end surface of the anisotropic conductive member at a 45 ° angle at a position corresponding to the peripheral end surface of the anisotropic conductive member. The wiring board according to claim 10, wherein the wiring board is formed on the one surface. 12. A first step of manufacturing a wiring board having a wiring line for forming a predetermined conductor pattern and a land on one surface corresponding to an electrode portion of an electronic component. The thickness of at least the region corresponding to each position where the wiring line intersects with the peripheral end of the anisotropic conductive member is the thickness of each region where the wiring line intersects with the peripheral end of the anisotropic conductive member. A second step of temporarily attaching the anisotropic conductive member having a shape thinner than a thickness in a region other than the region corresponding to the position to the one surface of the wiring board so as to cover the land; A third step of positioning and mounting the electrode portion of the electronic component on the corresponding land of the wiring board, and then thermocompression bonding the electronic component to the anisotropic conductive film under predetermined thermocompression bonding conditions. With Method of manufacturing a circuit board, wherein the door. 13. The method according to claim 12, wherein the peripheral end of the anisotropic conductive member is formed in a saw-like shape.