JPH10335359A - Manufacture of electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electronic component in which both the supply and packing of resin can be operated without troubles by applying a stencil printing means when a substrate is inclined, even when the substrate is not inclined. SOLUTION: In this method, a liquid sealing resin is supplied to at least one part of the surrounding of a flip chip loaded on a substrate, and the sealing resin is packed in a clearance based on a bump between the substrate and the flip chip by using capillary phenomenon. In this case, the supply of the sealing resin is operated by using a stencil printing means, and a stencil 1 is provided with a housing chamber 2, whose lower edge is opened and whose upper edge is closed for housing the flip chip, a supply path 3 acting as a squeegee into which the sealing resin is pushed, and a barrier 4 for separating the housing chamber 2 from the supply path 3 which is equipped with a communicating path 5 for allowing them to communicate to each other at the lower edge part. Thus, the sealing resin can be supplied directly from the supply path 3 through the communicating path 5 to the hosing chamber 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electronic component on which flip chips are mounted.

[0002]

2. Description of the Related Art In manufacturing the above electronic components, mounting of a flip chip is performed by connecting electrodes of the flip chip and electrodes of the substrate via bumps, and the substrate and the flip chip mounted on the substrate are mounted. And a gap based on the bump is generated between them. This gap is filled with a sealing resin for the purpose of improving the thermal cycle life.

Conventionally, such a sealing resin is filled by filling a liquid-like sealing resin into a syringe-like container and drawing and supplying it to the side of the flip chip while discharging the resin. It is performed by a method of impregnating using a capillary phenomenon, but this supply method has the following problems.

(A) Since the discharge amount is not constant and the positional accuracy is poor, the spread of the liquid sealing resin tends to be uneven.

(2) Since drawing is performed, it takes time to supply the sealing resin.

(C) A large number cannot be worked simultaneously.

In the case of a substrate on which chips having different sizes are mixed, the operation is difficult.

[0008]

The inventor of the present invention has practiced resin sealing of the surface and side surfaces of a chip such as a COB, TAB, or BGA in order to solve the problem of the resin supply method using the discharge drawing. An attempt was made to apply a resin supply method using stencil printing means to flip chips.

FIG. 10 is an explanatory view of the structure of an electronic component.
FIG. 11 is an explanatory view showing an example of a stencil applied to the stencil printing, and FIGS. 12 to 14 are explanatory views showing a state from supply to filling of the sealing resin by applying the stencil printing means in the order of steps.

Since the flip chip a is not usually sealed with a resin on the upper surface, as shown in FIG.
The upper end of the storage chamber 2 'of the flip chip a provided in the above is closed and only the lower end is opened. Further, the supply path 3 'for the sealing resin and the storage section 2' are separated by a partition 4 ', and the supply path 3' is provided along one side of the chip a.

Although the resin supply method using the stencil printing means can eliminate the problems a to d of the conventional method, there is no particular problem when the substrate is in a flat state as shown in FIG. As shown in FIG. 2B, when the substrate b is warped or tilted, the sealing resin e supplied through the supply passage 3 'by the operation of the squeegee f causes the chip a It has been found that there is a case where the gap d based on the bump c is not filled and the gap d is not filled.

The present inventors have conducted further intensive studies to eliminate the above problems, and as a result, have completed the present invention.

[0013]

According to the present invention, after a flip chip is mounted on a substrate via a bump, a liquid sealing resin is supplied to at least a part of the periphery of the flip chip, and the sealing resin is supplied to the substrate. In a method of manufacturing an electronic component that fills a gap based on a bump between a substrate and a flip chip by utilizing a capillary phenomenon, a stencil printing means is used to supply the sealing resin around the flip chip. At this time, as a stencil, a storage chamber with an open lower end and a closed upper end for storing the flip chip, a supply passage into which the sealing resin is pushed by operating a squeegee, a storage chamber and a supply passage By using a partition provided with a partition having a communication passage for communicating the two with the lower end thereof, the sealing resin is supplied from the supply passage via the communication passage to the storage chamber. The present invention relates to a method for manufacturing an electronic component, which is directly supplied to an electronic component.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an example of a stencil applied to the manufacturing method of the present invention. The stencil 1 is a storage chamber with an open lower end and a closed upper end for storing a flip chip a to be sealed with a resin including a bump c. 2, a resin supply passage 3 formed along one side of the storage chamber 2, and a partition 4 for isolating the supply passage 3 from the storage chamber 2. The communication passage 5 is formed below the lower end of the partition wall 4, and the supply passage 3 is communicated with the inside of the storage chamber 2 through the communication passage 5.

At the time of stencil printing, as shown in FIG. 2, the sealing resin e pushed into the supply passage 3 by the operation of the squeegee f passes through the communication passage 5 from the lower end of the supply passage 3 and enters the storage chamber 2. , So that, after printing, it comes into direct contact with the side of the flip chip a as shown in FIG.

Accordingly, in the case where the substrate b is slightly warped or the substrate b is slightly inclined (FIG. 14).
4), the supplied sealing resin e is in direct contact with the side surface of the flip chip a. Therefore, as shown in FIG. The gap d based on the bump c can be filled without any trouble by the combined use with the vacuum suction means.

Hereinafter, a stencil 1 applied to the production method of the present invention will be described.
Will be described in more detail.

The storage chamber 2 provided in the stencil 1 is formed slightly larger than the flip chip a in order to correct and absorb the dimensional error of the flip chip a. It is formed in such a size that a gap is formed.

It is advantageous for the top surface 2a (see FIG. 1), which closes the upper end of the storage chamber 2, to be as thin as possible within a range that can maintain the strength as the top surface, in order to reduce waste of the stencil material. Is appropriately selected from the range of about 0.01 to 1 mm in consideration of the material of the stencil material and the like.

FIG. 5 is a plan view showing a portion of the supply passage 3 in FIG. 1 and shows a case where the supply passage 3 is formed along one side of the storage chamber 2 over substantially the entire length thereof.

The supply passage 3 penetrates the stencil 1 as shown in FIG. The opening width D of the supply passage 3 (see FIG. 5) is not particularly limited as long as the supply amount of the sealing resin can be ensured. However, if it is too large, it will not meet the purpose of the flip chip of high-density mounting. It is appropriately selected from a range of about 1 to 3 mm.

If the vertical width of the communication path 5 is too small, the function of communication is not fulfilled. On the other hand, if it is too large, the sealing resin may enter the top surface of the flip chip due to excessive infiltration of the flip chip and contaminate the top surface. Because there is 0.01 ~
It is appropriately selected from the range of about 1 mm in consideration of the opening width D of the supply passage 3 and the like.

The supply passage 3 may be formed along at least one side of the storage chamber 2 as shown in FIGS.
In some cases, it may be formed along a plurality of sides of the four sides of the storage room 2.

FIG. 6 shows the supply passage 3 in the storage chamber 2 (see FIG. 7).
This shows a case in which the supply passages 3 are provided along all four sides. A space is provided between the supply passages 3 on each side, and the supply passages 3 on the four sides are formed by the space portions 6 as shown in FIG. The stencil 2 is the inside,
External parts 2A and 2B are integrally connected.

FIG. 8 is a sectional view taken along the line 8-8 in FIG. 7, and the partition walls 4 on the four sides around the storage chamber 2 are integrally connected at the space 6.

The communication passage 5 at the lower end of the partition wall 4 may be independent for each supply passage 2 or may be entirely connected. In the latter case, the lower end of the space 6 is cut off for communication with the communication passage 5. In FIGS. 1 and 7, reference numeral 7 denotes a recess formed on the outside of the supply passage 3 and recessed upward from the lower end thereof. The recess 7 is behind the liquid sealing resin to the stencil 1 by capillary action. The material of the stencil 1 for preventing the stencil is arbitrary, such as metals such as stainless steel, aluminum and copper, plastics, and inorganic materials such as glass and ceramic.

Processing of the holes and recesses of the stencil may be carried out in accordance with a conventional method. For example, cutting, laser or other physical processing, etching with a chemical solution, etc. for metals, and cutting, laser, etc. for plastics, etc. For example, physical processing such as casting, injection, and injection molding, and physical processing such as cutting and laser, and molding processing such as sintering are applied to inorganic materials.

When the stencil 1 is made of metal, as shown in FIG. 9, the stencil 1 has a three-layer structure of upper, middle, lower, 1a, 1b, and 1c, so that processing means such as cutting, laser cutting, and etching can be applied. And can be easily manufactured.

[0030]

According to the present invention, even when the substrate of the electronic component has no inclination or not, the resin is supplied from the resin supply to the flip chip by the stencil printing means into the gap based on the pump. It is possible to provide a method of manufacturing an electronic component that can perform a process up to filling without any trouble.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a stencil applied to the production method of the present invention.

FIG. 2 is a longitudinal sectional view showing a supply state of a liquid sealing resin by applying a stencil printing means in the manufacturing method of the present invention.

FIG. 3 is a longitudinal sectional view showing a state of supplying a liquid sealing resin to a flip chip.

FIG. 4 is a longitudinal sectional view showing a filling state of the liquid sealing resin.

FIG. 5 is a plan view schematically showing a positional relationship between a storage chamber and a supply passage.

FIG. 6 is a plan view showing another embodiment of a stencil.

FIG. 7 is a longitudinal sectional view of FIG.

FIG. 8 is a longitudinal sectional view taken along line 8-8 in FIG. 7;

FIG. 9 is a longitudinal sectional view showing an example of a stencil of the present invention having a three-layer structure.

FIG. 10 is an explanatory diagram of an electronic component mounted with a flip chip.

FIG. 11 is an explanatory view of a stencil studied in the present invention.

FIG. 12 is an explanatory view showing a situation in which a liquid sealing resin is supplied using the stencil shown in FIG. 11;

FIG. 13 is an explanatory diagram showing a situation after the resin is supplied.

FIG. 14 is an explanatory diagram showing the state of filling the supplied resin in a case where the substrate has no inclination and in a case where the substrate is not inclined.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stencil 2 Storage room 3 Supply passage 4 Partition wall 5 Communication passage 6 Interval 7 Depression

Claims (4)

[Claims] After a flip chip is mounted on a substrate via a bump, a liquid sealing resin is supplied to at least a part of the periphery of the flip chip, and the sealing resin is supplied between the substrate and the flip chip. In a method of manufacturing an electronic component that fills a gap based on a bump by utilizing a capillary phenomenon,
The supply of the sealing resin around the flip chip is performed by applying a stencil printing means. At this time, as a stencil, a lower-end open, upper-end closed storage chamber for storing the flip chip, and operation of a squeegee By using a supply passage into which the sealing resin is pushed, and a partition having a communication passage for isolating the storage chamber and the supply passage and communicating the lower end with the supply passage, And supplying the sealing resin directly from the supply passage to the storage chamber via the communication passage. 2. A stencil used for supplying a liquid sealing resin by applying a stencil printing means, wherein the flip chip is mounted on a substrate of an electronic component via a bump. A storage chamber with an open lower end and a closed upper end for storing the squeegee, a supply passage into which the liquid sealing resin is pushed by operating the squeegee, and a space between the supply passage and the storage chamber, which are connected to the lower end. A stencil provided with a communication passage for causing the stencil to have a stencil. 3. The stencil according to claim 2, wherein said supply passage is formed along at least one side of the storage chamber over substantially the entire length. 4. The supply passage has an opening width of 0.1 to 3 mm,
4. The stencil according to claim 2, wherein a vertical width of the communication passage is 0.01 to 1 mm.