JPH0551179B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a face-down bonding method.

[Prior art and its problems]

When a semiconductor chip such as a semiconductor integrated circuit is assembled onto a package or wiring board, the face-down bonding method is used to place the semiconductor chip face down, i.e., face down, and connect the electrode part with a surface with a larger area rather than with wires. ,
Compared to the face-up bonding method that involves wire bonding, the mechanical strength after connection is stronger.
It is said to be an advantageous method because only one bonding or connection is required.

This face-down bonding method usually
Bumps are formed in advance on the electrode portion of the semiconductor chip and the chips are fused downward (flip chip method), or bumps are formed in advance on the electrode portion of the substrate and the semiconductor chip is fused facing downward. The semiconductor chip and the substrate (package) are connected by the pedestal method.

This bump is chromium (Cr) - copper (Cu), aluminum (Al) - silicon (Si), aluminum -
Alloys such as copper, aluminum-copper-silicon, lead (Pb)-tin (Sn), titanium (Ti), aluminum,
It is made of metals such as chromium and nickel, or a laminate of these metals, and electrical connections are made by heating the semiconductor chip to a high temperature of 200 to 500°C and fusing it with the semiconductor chip placed on the desired position on the substrate. The goal is to achieve the following.

However, in these methods, (1) the steps required for bump formation are complicated and costly;

(2) Cracks are likely to occur when the bump is heated to a molten state.

(3) The metal forming the bumps diffuses into the element region within the semiconductor chip, degrading the characteristics of the element.

(4) When the metal forming the bump is heated and melted, it flows and shoots are generated, resulting in poor manufacturing yield.

There were other inconveniences.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a method for mounting a semiconductor device that eliminates the above-mentioned disadvantages, is easy to manufacture, and is highly reliable.

[Means for solving problems]

Therefore, in the present invention, a thermosetting adhesive having heat-shrinkable and insulating properties is used to seal the parts other than the electrode connecting parts on the substrate and the electrode connecting parts on the semiconductor chip so that they come into contact with each other. I'm trying to glue it together.

That is, by applying an insulating adhesive to a position other than the electrode connection part and heating it while applying pressure, the insulating adhesive is contracted and hardened, and the adhesive is applied to the electrode connection part and the area around the electrode connection part. Adhesion is achieved by curing.

[Effect]

That is, for example, as shown in FIG. 1a, metal bumps 2 are formed on the electrode portions 1a of the semiconductor chip, and heat-shrinkable and thermosetting bumps are formed at predetermined positions on the substrate 3 except for the electrode connection portions 3a. Fill with insulating adhesive 4.

Then, as shown in FIG. 1c, a semiconductor chip is placed on the substrate, and the adhesive is cured by heating in a reflow oven while applying pressure.

At this time, as the curing reaction progresses, the adhesive shrinks due to the vaporization of the solvent and reaction products, thereby increasing the adhesion between the semiconductor chip and the electrodes of the substrate and improving electrical connectivity.

In this way, a reliable connection is possible.

Furthermore, instead of forming the bumps on the electrode portions of the semiconductor chip, the bumps 2 may be formed on the electrode connection portions 3a on the substrate 3, as shown in FIG. 1B.

〔Example〕

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

Figure 2 a to d are for driving the image sensor.
FIG. 3 is a diagram showing an IC mounting process.

First, as shown in FIG. 2a, a wiring pattern (signal lead line) 12 made of a metal film for connection with a light receiving element part is formed on a glass substrate 11, and on an electrode pad part 12a of the wiring pattern 12, Bump 1 made of aluminum (Al) with a thickness of 1 μm using the thick film method
form 3.

Next, as shown in FIG. 2B, a thermosetting epoxy adhesive 14 is sequentially filled into predetermined positions on the substrate using a resin coater.

Subsequently, as shown in FIG.
Place it in a predetermined position and temporarily adhere it by applying pressure.

And finally, silicone sealing resin 16
was applied using a resin coater, and the adhesive and sealing resin were simultaneously cured at 150° C. for 30 minutes in a reflow oven, and the driving IC was bonded and sealed as shown in FIG. 2d.

In this way, a large number of semiconductor chips can be mounted in a single heating process, and workability is extremely good. In addition, since the electrodes are bonded under pressure, electrical Good connectivity and high reliability. Also, since the bumps only need to be in contact with the electrodes of the drive IC in a pressed state rather than fused, the heating temperature is low (adhesive curing temperature). There is no deterioration of device characteristics due to diffusion of bump constituent metal into the device region.

In addition, simple vertical pressure enables easy and reliable electrical connection and adhesion, and the periphery of each conductive pattern is fixed with insulating resin and well insulated. Therefore, there is no occurrence of shoots between adjacent electrodes.

Furthermore, if a connection failure occurs, the adhesive can be reused simply by melting and removing it with an organic solvent or the like, which improves yield.

In addition, since it occupies a small area in addition to being mounted using a wire bonding method or the like, it is possible to increase the packaging density and downsize the device.

In addition, in the example, it is used for driving the image sensor.
I explained the case where multiple ICs are mounted, but
Single semiconductor chip implementation or hybrid
This method can be applied to various situations including IC manufacturing, and this method can be used for wire bonding mounting,
Compared to bonding such as tab (TAB) and inner edge bonding, it is sufficiently superior in terms of takt time, material cost, and total cost.

Further, in the embodiment, the bumps were formed on the substrate, but they may also be formed on the semiconductor chip side.
If the electrode portion on the circuit pattern, semiconductor chip, or substrate has a convex shape, it may be used as is without forming any bumps.
Further, the metal constituting the bump is not limited to the examples, and any metal such as gold (Su), copper (Cu), chromium (Cr), etc. can be used.

Furthermore, the adhesive is not limited to epoxy resins, but may be any heat-shrinkable and thermosetting adhesive such as silicone resin or polyimide resin.

〔effect〕

As explained above, according to the present invention, by bonding the parts other than the electrode connection parts with an insulating thermosetting adhesive, the electrode connection parts on the substrate and the electrode connection parts on the semiconductor chip are bonded together. Since they are brought into contact with each other in a pressed state, it is possible to obtain a semiconductor device with a simple upper process requiring a low bonding temperature, a low cost, and high reliability.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of a method for mounting a semiconductor device according to the present invention, and FIGS. 2 a to 2 d are process diagrams for mounting an image sensor driving IC according to an embodiment of the present invention. 1... Semiconductor chip, 1a... Electrode connection part, 2
...Bump, 3...Substrate, 3a...Electrode connection part,
4... Insulating adhesive, 11... Glass substrate, 12
... Wiring pattern, 12a ... Electrode pad part, 1
3...Bump, 14...Epoxy adhesive, 15...
...Drive IC, 16...Sealing resin.

Claims (1)

[Claims] 1. When mounting a semiconductor chip consisting of a semiconductor integrated circuit element, etc. on a substrate provided with a wiring pattern, a heat-shrinkable and thermosetting material is placed at predetermined positions on the substrate excluding electrode connection portions. a coating step of applying an insulating adhesive; and a step of applying an insulating adhesive onto the substrate by heating and applying pressure to the electrode connection portion of the substrate and the semiconductor chip so that they come into contact with each other and electrical connection is possible. A method for manufacturing a semiconductor device, comprising an adhesion process for adhering semiconductor chips. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the substrate is formed by forming bumps on electrode pads serving as electrode connection parts.