JPH0521511A - Semiconductor element mounting structure - Google Patents

Abstract

PURPOSE:To prevent adjacent bumps from coming into contact with each other by providing a control member which controls the pressurizing force of a bonding head so that the electrode of a semiconductor element cannot come into direct contact with a wiring pattern. CONSTITUTION:A rectangular sheet-like polyimide protective film 15 is stuck in advance to the surface of a semiconductor element 3, on which bumps 2 are formed, as a control member. The thickness (e) of the film 15 is formed so that a relation b<e<b+d can be established among the thicknesses (e), (b), and (d) of the film 15, an inner lead 5, and the bumps 2. When such constitution is used, the pressing surface 8a of a bonding head 8 does not come into contact with the element 3, since the head 8 is brought into contact with the upper surface of the film 15 even when the bumps 3 melt due to heat and pressure at the time of bonding. In other words, when the pressing surface 8a of the head 8 is brought into contact with the upper surface of the film 15, the pressurizing force of the head 8 is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, TAB (Ta
pe Automated Bonding) technology, the invention relates to a mounting structure of a semiconductor device in which an inner lead of a film carrier and electrodes of a semiconductor device are connected via bumps (protruding electrodes).

[0002]

2. Description of the Related Art For example, TAB (Tape Automated Bonnd)
In the manufacturing process of a semiconductor device using the (ing) technique, there is an inner lead bonding process of mounting a semiconductor element on a film carrier as a circuit board.

In this inner lead bonding step, the semiconductor element is connected to the film by connecting the electrode portion of the semiconductor element and the inner lead (wiring pattern) of the film carrier through bumps. Implement on carrier. Generally, the inner lead bonding process is as shown in FIG.
This is performed by the inner lead bonding apparatus shown in (a) and (b).

Reference numeral 1 in FIG. 4 (a) is a bonding stage of the inner lead bonding apparatus. On the upper surface 1a of the bonding stage 1, a semiconductor element 3 having bumps (projection electrodes) 2 as connecting members formed on electrodes 3a is mounted with the surface on which the bumps 2 are formed facing upward. Placed. And this bonding stage 1
Positions the semiconductor element 3 in the vertical and XYθ directions.

Further, the inner lead bonding apparatus has a film carrier running means (not shown).
The film carrier running means feeds and drives the film carrier 4 in the direction shown by an arrow (a) in the figure, and the inner carrier is driven.
The device hall 6 having the protrusions 5 formed thereon is stopped above the semiconductor element 3.

Further, the inner lead bonding apparatus has a bonding head 8. The bonding head 8 is arranged above and above the bonding stage 1.

The bonding head 8 comprises a head body 9 and a heating chip 10 attached to the lower end surface of the head body 9. The head main body 9 is driven in the vertical direction by vertical drive means (not shown),
A heating heater 11 for heating the head body 9 to a predetermined temperature and keeping it warm is provided inside. Further, the lower surface of the heating chip 10 is formed to be substantially flat and constitutes a pressing surface 8a of the bonding head 8. Next, a mounting process of the semiconductor element 3 by this inner lead bonding apparatus will be described.

The above inner lead bonding apparatus is
By driving the bonding stage 1 in the XYθ directions, the bumps 2 of the semiconductor element 3 and the film carrier 4 are driven.
The inner leads 5 of the above are positioned so as to face each other.

Then, the inner lead bonding apparatus drives the bonding stage 1 to move upward, as shown in FIG.
As shown in (a), the clearance between the bumps 2 and the lower surface of the inner lead 5 is set to about 0 to 500 μm.
The inner lead bonding apparatus shown in FIG.
As shown in (b), the bonding head 8 is driven downward, and the inner leads 5 are pressed against the pressing surface 8a toward the semiconductor element 3 side and heated. As a result, the bump 2 is joined to the inner lead 5.

That is, gold is generally used as a material for the bumps 2 (gold bumps), and by heating under pressure, tin or the like plated on the inner lead 5 and a eutectic alloy are used. Combine and combine. As a result, the electrode 3a of the semiconductor element 3 and the inner lead 5 are connected via the bump 2.

[0011]

By the way, since the bumps 2 made of gold are very expensive, it has recently been considered to use a relatively inexpensive solder material (solder bump).
In this case, the electrode 3a of the semiconductor element 3 and the inner lead 5 are connected by utilizing the heat melting property of the solder material.

However, with the mounting structure as described above,
When the solder material reaches the melting point, the bumps 2 are melted all at once, and the inner lead 5 is transferred to the semiconductor element 3 by the bonding head 8 as shown in FIG. 4B.
The electrode 3a may be directly pressed. As a result, the bump 2 becomes the electrode 3 of the semiconductor element 3.
There is a problem that the bumps 2 which are extruded by the a and the inner lead 5 and are provided on the adjacent electrodes 3a come into contact with each other and are shorted.

The present invention has been made in view of the above circumstances, and when the electrodes of the semiconductor element and the wiring patterns of the circuit board are connected via the bumps, the bumps are bonded at the time of bonding. It is an object of the present invention to provide a semiconductor element mounting structure that can effectively prevent being pushed out and contacting adjacent bumps.

[0014]

SUMMARY OF THE INVENTION The present invention is a semiconductor element mounting structure in which an electrode of a semiconductor element and a wiring pattern are bonded via bumps by using a bonding head. At least one of the facing surface and the surface facing the bonding head side of the wiring pattern is provided with a sheet-shaped restricting member for restricting the pressure applied to the wiring pattern. Characterize.

[0015]

According to this structure, at the time of bonding,
Even if the bump is melted, the regulating member prevents the electrode of the semiconductor element and the wiring pattern of the circuit board from directly contacting each other.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The same components as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1A, on the surface (upper surface) of the semiconductor element 3 used in the mounting structure of the present invention on which the bumps 2 are formed, a rectangular sheet-shaped polyimide as a regulating member is formed. The protective film 15 made of is attached in advance.

As shown in FIG. 2, this protective film 15
The thickness e of the inner lead 5 is formed to have a relationship of b <e <b + d, where b is the thickness of the inner lead 5 and d is the thickness of the bump 2.

With such a structure, as shown in FIG. 1B, even if the bump 2 is melted by being heated and pressed during bonding, the pressing surface 8a of the bonding head 8 is pressed. Touches the upper surface of the protective film 15 and cannot approach the semiconductor element 3 any more.

That is, when the pressing surface 8a of the bonding head 8 comes into contact with the upper surface of the protective film 15, the pressing force of the bonding head 8 is restricted. The thickness e of the protective film 15 is the inner layer.
The inner lead 5 is not directly pressed against the electrode 3a of the semiconductor element 15 because it is formed to be thicker than the thickness b of the terminal 5.

This prevents the bump 2 from being extruded by the bonding head 8 from between the inner lead 5 and the electrode 3a of the semiconductor element 3, so that the bump 2 is adjacent to the bump 2. The contact with the bumps 2 is reduced.

Therefore, even when a highly fusible material such as a solder material is used as the material of the bumps 2, it is possible to effectively prevent the adjacent electrodes 3a and 3a of the semiconductor element 3 from being short-circuited. Therefore, high quality bonding can be performed. The present invention is not limited to the above-described embodiment, and various modifications can be made without changing the gist of the invention.

In the above embodiment, the semiconductor element 3 is
The mounting structure is one in which the semiconductor device 3 is mounted on the film carrier 4, but the mounting structure is not limited to this.
Can also be applied to a mounting structure in the case of directly mounting (flip chip type) on a glass substrate as a circuit substrate on which a wiring pattern is formed.

That is, as shown in FIG. 3A, a protective tape 15 'made of polyimide is attached to the portion of the circuit board 16 where the wiring pattern 17 is formed. Openings 19 are provided in portions of the protective tape 15 'corresponding to the bumps 2 ...

Then, the thickness e'of the protective tape 15 'is
Similarly to the above-mentioned embodiment, b '<e'<b'+, where b'of the wiring pattern and d'is the thickness of the bump 2.
They are formed to have a relationship of d '.

Therefore, even when the semiconductor element 3 is mounted on the circuit board 16 by the flip-chip method, as shown in FIG. 3B, the distance between the semiconductor element 3 and the circuit board 16 is set to the protective tape. -Regulated by 15p '. As a result, the amount of lowering of the bonding head 8 can be regulated to such an amount that the electrode 3a of the semiconductor element 3 does not directly contact the wiring pattern 17 of the circuit board 16.

Further, in the above-mentioned embodiment, the sheet-like regulating member has the structure in which the protective tape 15 is attached, but an electrically insulating member having a predetermined thickness (either organic or inorganic may be used). If it is good. For example, a resin having a predetermined thickness is coated on the semiconductor element 3 before the bumps 2 are formed, and only the resin on the electrode 3a of the semiconductor element 3 is removed by means such as etching to form an opening. By means such as plating on the electrode 3a exposed in the opening,
The bump 2 having a height equal to or larger than the thickness of the coated resin may be formed.

In the above embodiment, the protection tape 15 is used.
Although the position of the pressing surface 8a is regulated by the above, a sheet-shaped regulating member lower than the height of the bump 2 may be provided around the bump 2.

[0029]

As described above, in the semiconductor element mounting structure of the present invention, the regulating member for regulating the pressing force of the bonding head so that the electrodes of the semiconductor element and the wiring pattern do not come into direct contact with each other. Was set up.

According to this structure, even if the bump is made of a heat-meltable material, the bump is pushed out by the electrode of the semiconductor element and the electrode of the wiring pattern at the time of bonding to be adjacent to the bump. It is possible to effectively prevent the matching bumps from contacting each other.

[Brief description of drawings]

1A and 1B are front views with a partial cross section showing an embodiment of the present invention.

FIG. 2 is an enlarged front view showing the same.

FIG. 3A and FIG. 3B are front views with partial cross-sections showing other embodiments.

4A and 4B are front views each showing a conventional example with a partial cross section.

[Explanation of Codes] 2 ... Gold bump, 3 ... Semiconductor element, 3a ... Electrode, 4 ... Film carrier, 5 ... Inner lead (wiring pattern),
8 ... Bonding head, 15 ... Protective film (regulating member).

Claims (1)

Claim: What is claimed is: 1. A semiconductor element mounting structure in which an electrode of a semiconductor element and a wiring pattern are bonded via bumps by using a bonding head, and the semiconductor head is opposed to the bonding head side of the semiconductor element. At least one of the surface and the surface of the wiring pattern facing the bonding head side is provided with a sheet-shaped regulating member for regulating the pressure applied to the wiring pattern. Semiconductor element mounting structure.