JPH04152540A - Mounting method of semiconductor device - Google Patents

Abstract

PURPOSE:To keep the reliability and the quality of a connection at a high-density mounting operation by a method wherein an electrode for a semiconductor device is coated with a conductive adhesive, conductive components in the adhesive are made to cohere to the central part of the electrode and the electrode on the semiconductor device is connected to an electrode on a board. CONSTITUTION:A semiconductor device 2 is mounted on a board 3 in a faced-down state. At the mounting method of the semiconductor device 2, an electrode 5 for the semiconductor device 2 is coated with a conductive adhesive 1, conductive components 6 in the adhesive 1 are made to cohere to the central part of the electrode 5 and, after that, the electrode 5 on the semiconductor device 2 is connected to an electrode 4 on a board 3. For example, the face of an active element having an electrode 5 for a semiconductor device 2 is faced downward. Then, the electrode 5 for the semiconductor device 2 is coated with an anisotropic conductive resin (resin) 1. While the electrode 5 is faced downward and the viscosity of the resin 2 is lowered by instantaneously heating the electrode 5, conductive components 6 are made to cohere to a part near the central part of the resin 1. Then, the electrode 5 is aligned with an electrode 4 on a board. Both electrodes are connected by executing a pulse heating operation which repeates a heating operation and a cooling operation.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for mounting a semiconductor device, and particularly to a method for directly mounting a semiconductor device on a substrate in a face-down manner.

<Prior art> Various methods are used for mounting semiconductor devices, but in response to the increasing number of pins in integrated circuits, there are various methods ranging from wire bonding to T A B (Tape Auto).
Mounting methods such as bonding (attached bonding) and flip chip bonding are used. In addition, for face-down mounting methods, stamping methods using conductive paste or anisotropic conductive adhesive have recently begun to be widely adopted, but the conductive component in the adhesive is always dispersed into powder. is taken into consideration.

<Problems to be Solved by the Invention> In the face-down mounting method described above, when the size of the electrodes on the semiconductor device is reduced due to high-density mounting, the conductive component in the conductive resin The number of particles present decreases, reducing the reliability and quality of the connection. In order to cope with this, increasing the concentration of particles in the resin causes problems such as leakage between electrodes and a decrease in adhesive strength between the semiconductor device and the substrate. Therefore, the present invention has been developed to improve the connection reliability,
The purpose is to maintain quality.

<Means for Solving the Problems> In order to solve the above problems, the present invention provides a mounting method for a semiconductor device in which a semiconductor device is mounted face down on a substrate. A method is used in which a conductive adhesive is applied, a conductive component in the adhesive is aggregated at the center of the electrode, and then the electrode on the semiconductor device and the electrode on the substrate are connected.

<Function> By using the above means, when the semiconductor device and the electrode on the substrate are connected,! The concentration of the conductive component near the very center becomes high, resulting in good conduction.

<Example> The present invention will be described in detail below using an example in which an anisotropic conductive adhesive is used.

FIG. 1 shows an example of the present invention using an anisotropic conductive resin (hereinafter referred to as "
1) is applied to the electrode 5 of the semiconductor device 2, and with the surface of the semiconductor device 2 facing downward, the resin 1 is applied.
It shows that the conductive components 6 are gathered near the center of the figure. FIG. 2 shows that the resin l is applied to the electrode 5,
The conductive component 6 is shown concentrated in the center of the resin 1 and then bonded to the electrode 4 on the wired substrate 3. As the conductive resin 1, for example, in an epoxy adhesive, fine particles of Cu and C, which are conductive components, are mixed with A g+
This is a dispersion of N i + A u plating.

Next, the implementation procedure will be explained.

The active element surface of the semiconductor device 2 with the electrode 5 is faced down.

Next, as shown in FIG. 3, the resin l is placed on the rotating plate 8,
Apply Nuki-Sif to spread the paste layer, press the electrode 5 on the resin surface, apply the resin 1 to the surface of the electrode 5 or the entire active element surface, and make sure that the electrode 5 is facing downward and By momentarily heating the electrode 5 and lowering the viscosity of the resin 1, the conductive component 6 is aggregated near the center of the resin 1. As a heating method, a heater (tungsten, molybdenum heater) is provided in the cholera 1 part that chucks the semiconductor device, and the back surface of the semiconductor device 2 is pressed with a heated collet to heat the semiconductor device 2 from the back surface to 150°C.
A method is used in which the material is heated for a few seconds at around tSO°C and then cooled down to 100°C or less by cooling down with air blowing or the like.

Even when the resin 1 is applied to the entire active surface, the electrode 5 has a convex shape, so when the electrode 5 faces downward, the applied resin 1 also becomes convex downward, so the electrode 5 should be moved downward. By directing and heating the conductive component 6, it is possible to aggregate the conductive component 6 in the center of the resin 1.

After the conductive component 6 is aggregated in the center of the resin 1 by the above procedure, the heating and cooling described above are repeated to align and connect the tFM 5 to the substrate electrode 4.
Connection is made by vs heating.

In addition, when using an isotropic conductive resin as an adhesive, the isotropic conductive resin is applied only to the electrode 50 surface, and is made to aggregate in the center in the same manner as described above, and then connection is performed.

<Effects of the Invention> As explained in detail above, by using the present invention, even if the content of the conductive component is reduced, good electrical conductivity can be maintained at the center of the electrode by aggregating it in the center. Not only can connection be made, but also the mechanical adhesion strength can be increased in the peripheral area where there is little conductive component. Furthermore, even if the resin bleeds out of the electrodes during adhesion, the concentration of the conductive component in this bleed component is low, so that leakage between the electrodes is also prevented.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conductive component concentrated near the center of the resin in an embodiment of the present invention. FIG. 2 is a diagram showing a bonding state between an electrode of a semiconductor device and an electrode of a substrate. 3rd oral history) and et al.) are diagrams showing the squeegee method. Explanation of symbols 1: Anisotropic conductive resin, 2: Semiconductor device, 3: Substrate,
4: Wiring electrode on connection substrate, 5: Wiring electrode on semiconductor device for connection, 6: Conductive component in anisotropic conductive resin,
7: Squeegee, 8: Rotating plate. Agent Patent attorney Ume 1) Katsu (and 2 others) Figure ■

Claims (1)

[Claims] 1. In a semiconductor device mounting method in which a semiconductor device is mounted face down on a substrate, a conductive adhesive is applied onto the electrode of the semiconductor device, and the conductive component in the adhesive is applied to the center of the electrode. 1. A method for mounting a semiconductor device, which comprises connecting an electrode on the semiconductor device and an electrode on a substrate after agglomerating the semiconductor device into a portion.