JPH02275650A - Mounting structure of semiconductor element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a mounting structure (hereinafter referred to as T
This is related to A B 4N construction).

[Conventional technology]

In the conventional TAB structure semiconductor device mounting structure, connection terminals are formed in a single row or in a staggered arrangement around the outer periphery of the semiconductor device.
A connecting medium of uniform height was used to connect one or two film carriers as described in Japanese Patent Publication No. 63-22461.

[Problem to be solved by the invention]

However, in the above-mentioned mounting structure, the terminal pitch of the connecting terminals is limited by the production capacity of the finger leads of the film carrier, and the terminal pitch is 7.
The limit was 0 μm to 80 μm. For this reason, the number of terminals that can be formed in one semiconductor element is limited by the outer periphery of the semiconductor element, making multi-bin mounting difficult. It's there to provide.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention provides a mounting structure for electrically connecting a semiconductor element terminal and a finger lead of a film carrier, in which a terminal is formed on at least either the semiconductor element or the finger lead of the film carrier. The height of the connecting medium is increased toward the inner circumference of the semiconductor element from the outer circumference of the semiconductor element, and a plurality of film carriers are connected to one semiconductor element in multiple layers.

〔Example〕

Embodiments of the present invention will be described below based on the drawings, but the present invention is not limited thereto.

FIG. 1 shows a mounting structure according to the present invention. Semiconductor element 1 and film carriers 5-7 are electrically connected by connection media 2-4. Here, the connecting media 2 to 4 are formed such that the height of the connecting medium increases from the outermost connecting medium 2 to the inner connecting medium 4.

Here, since there are three possible methods for forming the connection media 2 to 4, each method will be explained step by step.

1. A method of forming a connection medium on an aluminum pad formed on a semiconductor element by a plating method.

In this method, connecting media 2 to 4 are formed on all the aluminum pads by plating as shown in FIG. As shown in b), a resist 8 is applied onto the top of the connecting medium 2 using a spinner or a roll coater. This is then plated again to form a connecting medium 3.4. When the connecting medium 3 has grown to the desired height, a resist 9 is applied to the top of the connecting medium 3 using the above method as shown in FIG. 2(c). Apply and re-paste. By repeating this process multiple times, it is possible to obtain a desired number of connecting media with different heights. A semiconductor device constructed using this method is shown in FIG. Also, at this time, the natural quality of the connection medium is normal TAB.
Au, solder, etc. used in

2. A method of transferring a connecting medium to the finger leads of a film carrier.

This method is based on the National Technical Revo-t
- Using the method introduced in Vol. 31 (published in 1985), connecting media of different heights are transferred to a plurality of film carriers.

3. A method in which the finger leads of the film carrier are partially etched so that the parts that contact the aluminum pads of the semiconductor element are hardened.

In this method, as shown in FIG. 4, projections 13 are formed on the finger leads by applying a resist 12 to the portions of the conductor pattern 11 formed on the film carrier 11 that contact the aluminum pads of the semiconductor element and etching them.

At this time, the thickness of the conductor pattern becomes thicker as it goes toward the inner periphery, and the etching time at this time is made longer for the film carrier culm connected to the inner periphery of the semiconductor element, so that tall protrusions can be formed. It can be formed. At this time, the conductive pattern may be made of Cu or the like used in ordinary FPCs.

Next, the semiconductor element and the finger leads of the film carrier are electrically connected via the connection medium formed on the semiconductor chip side or the film carrier side as described above. Here, a connection method will be explained step by step for a device in which a connection medium is formed by plating on the semiconductor element side.

First, in FIG. 5(a), the outermost terminal 2 of the semiconductor element 1 and the first film carrier 5 are aligned and then thermocompression bonded using the heat tool 14. At this time, the heat tool 14 needs to have a concave structure so as not to come into contact with the connecting medium formed high inside. Next, the fifth
As shown in Figure (b), the semiconductor element and the second film carrier 6 are aligned using the second lowest connecting medium 3, and then thermocompression bonded using the heat tool 15. At this time, the heat tool 15 is connected to the connecting medium 4 formed high inside and as shown in FIG.
It is necessary to have a concave shape and a small external shape so as not to contact the fingers 5 connected in a).

Next, as shown in FIG. 5(C), a third film carrier 7 is connected in the same manner as described above.

By repeating this process multiple times, any number of film carriers can be connected. Here, in order to prevent the fingers of the overlapping film carriers from electrically contacting each other, it is desirable to form the fingers of the film carrier that will be connected later by pressing, etc. in the direction as shown in Figure 1. . Also, the heat tool can be a constant heat tool that heats up all the time, or a pulse heat tool that instantaneously generates heat when crimping, but when considering the temperature distribution inside the tool, a constant heat tool is more stable. It is desirable because it is

Next, in order to increase the connection strength of the modules connected as described above and to isolate them from the outside air, the connection portions are protected with epoxy resin 17 or the like as shown in FIG. 6.

Protection methods at this time include transfer molding,
A possible solution is to use a dispenser or the like to remove the green beans.

Furthermore, this mounting structure allows the fingers of the film carrier to be exposed in any manner corresponding to the terminal layout of the semiconductor chip with respect to the four sides of the semiconductor element.

〔Effect of the invention〕

As explained above, in the present invention, a semiconductor element is connected to one semiconductor chip by forming a connection medium at one of the nodes of a finger of a film carrier such that the height increases from the connection terminal on the outer periphery of the semiconductor chip toward the inner periphery. However, by connecting multiple film carriers in multiple layers, the terminal pitch of the connecting terminals can be mounted without being restricted by the manufacturing capacity of the film carrier or the outer periphery of the semiconductor element, allowing high-density mounting with conventional semiconductor elements. This has the effect of enabling multi-bin packaging.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a mounting fM structure of a semiconductor element of the present invention. FIGS. 2(a) to 2(C) are cross-sectional views illustrating the process of forming a connecting medium by a plating method. FIGS. 3(a) and 3(b) are diagrams showing a semiconductor chip with a connecting medium formed by the plating method, and (a) is a diagram showing a cross section (
b) is a top view. FIGS. 4(a) and 4(b) are cross-sectional views illustrating the process of forming a connecting medium by an etching method. FIGS. 5(a) to 5(c) are cross-sectional views illustrating the mounting process. FIG. 6 is a sectional view showing the protected state of the joint. 1... Semiconductor elements 2-4... Connection medium 5-7... Finger of film carrier 8.9...
・Resist 10...Film carrier 11...Conductor pattern 12...Resist 13...Protrusions 14 to 16...Heat tool 17...Protective film 2 Applicant: Seiko Epson Corporation Representative Patent attorney 1 (a) (b) (C) Figure 2 Figure 4 (a) Figure 3 Figure 5

Claims (1)

[Claims] In a semiconductor element mounting structure that electrically connects a semiconductor element terminal and a finger lead of a film carrier,
The height of the connecting medium formed on at least either the semiconductor element or the finger leads of the film carrier is increased from the outer periphery of the semiconductor element toward the inner periphery; A semiconductor device mounting structure characterized by a plurality of film carriers connected to the device in multiple layers.