JPH0927518A - Method of bonding electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of bonding an electronic component by which an electronic component can be bonded in a short time even when a substrate does not have permeability. SOLUTION: This method comprises the step of applying an anaerobic bonding agent 3 to an electrode 2 formed in the surface of a substrate 1 so as to cover it and the step of pushing the bump 5 of an electronic component 4 against the electrode 2 to which the anaerobic bonding agent 3 is applied, thereby forming the state of low oxygen in a space between the substrate 1 and the electronic component 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component bonding method for bonding an electronic component having bumps to a substrate using an adhesive.

[0002]

2. Description of the Related Art A method of using an ultraviolet curable resin (hereinafter simply referred to as "UV resin") is known for adhering an electronic component having bumps to a substrate with an adhesive.

In this device, UV resin is first applied to the substrate, and then the electronic parts are pressed and pressed against the substrate while U
The UV resin is irradiated to cure the UV resin. It is also known to apply a thermosetting resin to a substrate and then heat the electronic component while applying pressure to cure the resin.

[0004]

By the way, when the electronic component is bonded to the substrate, the bump is sandwiched between the electronic component and the substrate. Therefore, in order to cure the UV resin applied around the bumps, it is necessary to irradiate UV from the back side of the substrate so that the UV passes through the substrate.

Therefore, there is a problem that only a substrate having transparency such as glass can be used as a substrate, and a substrate having no transparency cannot be applied. Further, in order to sufficiently cure the UV resin, it is necessary to continue irradiating UV while pressing the electronic component against the substrate for a long time of 30 seconds or more, and there is also a problem that the tact time required for bonding is long.

Therefore, an object of the present invention is to provide an electronic component bonding method capable of bonding electronic components in a short time even on a non-transparent substrate.

[0007]

An electronic component bonding method according to the present invention comprises a step of applying an anaerobic adhesive so as to cover an electrode formed on a surface of a substrate, and an electrode coated with the anaerobic adhesive. Pressing the bumps of the electronic component to form a hypoxic condition in the space between the substrate and the electronic component.

[0008]

With the above structure, the electrodes of the substrate are coated with the anaerobic adhesive, and the bumps of the electronic component are pressed against the electrodes, whereby the substrate and the electronic components are filled with the anaerobic adhesive. That is, most of the air in the space between the substrate and the electronic component is pushed out by the anaerobic adhesive,
A low oxygen state is formed in this space, which triggers the curing of the anaerobic adhesive, and the electronic component is bonded to the substrate.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1A to 1D are process explanatory diagrams of an electronic component bonding method in an embodiment of the present invention. FIG.
In FIG. 1, reference numeral 1 denotes a substrate (which may or may not be transparent like glass), and 2 is an electrode formed on the surface of the substrate 1. Here, the electrode 2 is made of copper in order to act as a catalyst for promoting the curing of the anaerobic adhesive. Reference numeral 3 is an anaerobic adhesive applied so as to cover the electrode 2, 4 is an electronic component to be bonded to the substrate 1, and 5 is a bump protruding from the lower surface of the electronic component 4. Like the electrode 2, the bump 5 is also made of copper so as to function as a catalyst.

Now, as shown in FIG. 1A, an anaerobic adhesive 3 is applied so as to cover the electrodes 2 of the substrate 1. Next, as shown in FIG. 1B, the electronic component 4 is pressed in the arrow direction, and the bumps 5 are strongly pressure-bonded to the electrodes 2. The pressure bonding time may be approximately 10 seconds or less. By this pressure bonding, the bumps 5 and the electrodes 2 are strongly pressed, so that the bumps 5 made of copper and the electrodes 2 come into close contact with each other, and the anaerobic adhesive 3 on the electrodes 2 causes a space between the substrate 1 and the electronic component 4. This space is pushed to the bottom, and this space is almost filled with the anaerobic adhesive 3 and becomes a hypoxic state with no air. When this low oxygen state is formed, the anaerobic adhesive 3 begins to cure from the portion in contact with the electrodes 2 and the bumps 5 by the catalytic action of the electrodes 2 and the bumps 5. The anaerobic adhesive 3 that is in contact with at least the electrode 2 and the bump 5 as indicated by the diagonal lines in FIG.
The state in which the bump 5 is pressed against the electrode 2 is maintained until is cured. A short time of 10 seconds or less is sufficient for this pressure bonding. Then, as shown in FIG. 1C, the pressure bonding is released when the anaerobic adhesive 3 is cured. Since the bump 5 is firmly fixed to the electrode 2 by the hardened anaerobic adhesive 3, there is no problem even if the pressure bonding is released at this point. After that, the anaerobic adhesive 3 is left until it is completely cured. When a part of the anaerobic adhesive 3 starts to be hardened, the hardening phenomenon spreads to the surroundings, and the entire anaerobic adhesive is hardened, as shown in FIG.

Here, in each step of the bonding method shown in FIG. 1, it may be carried out in an atmosphere in which oxygen is blocked, but sufficient bonding can be carried out without particularly blocking oxygen.
As shown in FIG. 1C, heating is performed at a temperature that does not damage the electronic component after the pressure bonding is completed, and as shown in FIG. 1D, the entire anaerobic adhesive 3 is cured. The time may be shortened. At this time, it is more preferable to add a thermal catalyst to the anaerobic adhesive 3.

[0013]

According to the method of bonding electronic components of the present invention, in this embodiment, the electrodes 2 and the bumps 5 are made of a metal (for example, copper, aluminum, etc.) having a catalytic action for promoting the curing of the anaerobic adhesive 3. By doing so, the anaerobic adhesive 3 contacting the electrodes 2 and the bumps 5 can be cured first to fix the bumps 5 to the electrodes 2, and as a result, the working time for adhering the electronic component 4 to the substrate 1 is further improved. It can be shortened. Even if the electrodes 2 and the bumps 5 are formed of a material having no catalytic action, the time required for the anaerobic adhesive 3 to cure is shorter than that of the UV resin used in the past, so that the working time is shortened. It can bond electronic components with bumps to the substrate not only on the glass substrate but also on other types of substrates. can do.

[Brief description of drawings]

FIG. 1A is a process explanatory diagram of an electronic component bonding method according to an embodiment of the present invention. FIG. 1B is a process explanatory diagram of an electronic component bonding method according to an embodiment of the present invention. (D) Process explanatory drawing of electronic component bonding method in one example of the present invention

[Explanation of symbols]

 1 substrate 2 electrode 3 anaerobic adhesive 4 electronic component 5 bump

Claims (5)

[Claims] 1. A step of applying an anaerobic adhesive so as to cover an electrode formed on a surface of a substrate, and a bump of an electronic component is pressed against the electrode coated with the anaerobic adhesive to form the substrate. Forming a low oxygen state in a space between the electronic component and the electronic component. 2. The method for adhering an electronic component according to claim 1, wherein after the low oxygen state is formed, the state in which the bump is pressed against the electrode is maintained at least until the anaerobic adhesive is cured. 3. The method for adhering electronic components according to claim 1, wherein the bumps and / or the electrodes are made of metal having a catalytic action for promoting the curing of the anaerobic adhesive. 4. The method for adhering electronic components according to claim 1, wherein the bumps and / or the electrodes are made of copper. 5. The method for adhering an electronic component according to claim 1, wherein the bump is pressed against the electrode for 10 seconds or less.