JPH0379050A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To improve yield, reduce cost, and achieve improved reliability by placing a tape carrier with a conductor pattern where a bump is formed at the tip of a lead being at the lower side onto a semiconductor chip, performing alignment, and then enabling a bonding tool to abut from an insulating film side and then performing heating and applying pressure. CONSTITUTION:With a conductor pattern of a tape carrier 9 at the lower side, the tape carrier 9 is placed on a semiconductor chip 5 where a bump 6 is formed on the upper-surface side, thus matching the position of the bump 6 on a chip and a bump 8 at the tip of a lead of the conductor pattern. Then, by applying a bonding tool 7 from the side of an insulating film 1, the semiconductor chip 5 is connected to a conductor pattern while pressing. Thus, by forming the slight bump 6 at the semiconductor chip 5, tolerance of setting such as temperature, time, and pressure of bonding can be expanded, thus achieving an improved yield, low cost, and improved reliability.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for mounting a semiconductor chip on a tape carrier.
The present invention relates to a method for manufacturing a tape carrier type semiconductor device.

[Conventional technology]

In recent years, tape carrier systems have been viewed as promising for devices using semiconductors, such as displays and electronic computers, to make them smaller, thinner, and more dense. however,
Conventional tape carriers have disadvantages in that the process is complicated because it is necessary to form leads that protrude into the device hole, the yield is poor because the leads are unstable and deform, and the cost is therefore extremely high.

In order to solve this problem, the present inventors have previously invented and disclosed a method for mounting a semiconductor chip without forming leads that protrude into device holes. As shown in Figure 2, bumps (6) are first formed on a conductor pattern formed on a flexible substrate made by gluing an insulating film (1) and a conductor (2) together with an adhesive (3). The semiconductor chip (5) having a structure formed on its upper surface is aligned face down. After that, the bonding tool (7) is brought into contact with the insulating film side, and the connection part of the lead end of the conductor pattern and the bump (6) on the semiconductor chip are heated and pressurized via the insulating film (1). The semiconductor chip (5) is mounted by this method, and a tape carrier type semiconductor device is completed.With this method, there is no need to form device holes, so the number of steps is reduced.
Moreover, since there is no defect such as deformation of the conductor lead protruding into the device hole, the yield is high and the cost is low, and the reliability of the connection part is high.

However, the temperature, time, and pressure during bonding are generally set depending on the insulating film that makes up the tape carrier, the copper foil (conductor), the type and thickness of the surface plating, etc., but this method In this case, the setting tolerance range is narrow, especially since bonding is performed at a high temperature of 400 to 500°C, so if the setting tolerance range is exceeded, the insulating film may thermally decompose or the connection will not be possible at all, resulting in lower yields. It turns out that the drawback is that it becomes lower.

[Problem to be solved by the invention]

The present invention was developed as a result of various studies in view of the above drawbacks of the prior art, and its purpose is to provide a tape carrier system with high yield, low cost, and high reliability. The purpose of the present invention is to provide a semiconductor device.

[Means to solve the problem]

That is, the present invention provides a method for manufacturing a semiconductor device in which a semiconductor chip is mounted on a tape carrier having a circuit pattern formed of a conductor on a flexible insulating film, and a conductor pattern having bumps formed at the tips of the leads. A tape carrier with the tape carrier facing downward is placed on a semiconductor chip on which bumps have been formed, and after alignment, a bonding tool is brought into contact with the insulating film side and heated and pressurized. It's a method.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a diagram showing a method of manufacturing a semiconductor device according to the present invention. Connect the insulating film (1) and conductor (2) with adhesive (
The tips of the leads of the conductive pattern formed by photo-etching or other methods on the flexible substrate bonded in step 3) are removed by plating, etching, or other methods to form bumps (8), and the surface is plated (4). ) A tape carrier (9) is prepared.

With the conductor pattern of this tape carrier (9) facing downward, the semiconductor chip (5) has bumps (6) formed on its upper surface.
) and align the bumps (6) on the chip with the bumps (8) at the ends of the leads of the conductor pattern. S*, apply the bonding tool (7) from the insulating film (1) side and connect the semiconductor chip (5) to the conductive pattern while pressing.

In this way, similarly to the semiconductor chip (5), by forming just a few bumps (8) on the leads of the conductive pattern, it is possible to expand the allowable range of temperature, time, and pressure settings for bonding. The semiconductor chip (5) can be mounted extremely easily.

The laminate of the insulating film (1) and the conductor port used in the present invention is not particularly limited as long as it is normally used as a flexible printed circuit board. ), it is desirable that the insulating film (1) and adhesive (3) be heat resistant, such as polyimide resin, and as thin as possible.

Furthermore, a metal film is formed on the insulating film (1) by a method such as vapor deposition, sputtering, plating, or
No adhesive is used, obtained by coating insulating resin such as epoxy resin or polyimide resin on metal foil and drying it.
A laminate with a layered structure provides better results because there are fewer layers that reduce heat resistance or block heat during heating and pressurization using a bonding tool.

In tape carrier type semiconductor devices with normal device holes, plating and bumps are used instead of bumps on the semiconductor chip.
Etching, transfer, etc. have been devised to form bumps on the tips of the leads that protrude into the device holes, but because the leads are thin and unstable, the process is long and yields are high (and costs are high). In contrast, the bump (8) on the tip of the lead of the conductor pattern in the present invention
Since there is an insulating film (1) on the back of the lead, the formation of the lead is done by applying a thick plating to only the tip of the lead.
This can be easily done by a commonly used method such as applying a conductive paste or etching the part other than the tip, and the method is not particularly limited.
Further, the height of the bump (8) is not particularly limited, but considering the effect, it is preferably between 1 and 50 μm.

The surface of the conductor pattern is plated (4), and the material is not limited to gold, tin, solder, etc., but it is better to match the material of the bumps (6) on the semiconductor chip (5). preferable.

The bonding tool (7) used in the method of the present invention is:
It is not particularly limited as long as it can be heated and pressed at 600° C. for 1 second at 200 g/lead or more and has a parallelism with the semiconductor chip of 5 μm or less and is commonly used.

As described above, the present invention can eliminate the drawback of difficulty in controlling the bonding conditions of the new film carrier type semiconductor device manufacturing method that does not require device holes, and can achieve high yield, low cost, and high multiplication. A film carrier type semiconductor device is obtained.

Examples of the present invention and comparative examples using conventional methods will be shown below.

〔Example〕

A polyimide resin was coated on an electrolytic copper foil having a thickness of 35 μm and dried to form an insulating layer having a thickness of 25 μm to obtain a laminate having a two-layer structure. This was slit into a tape shape with a width of 35 m, and the copper foil surface was patterned by etching. After that, apply a mask and partially plate the tip of the lead to a height of about 10μ.
A tape carrier was obtained by forming bumps of m in diameter and plating the surface with 1.0 μm of gold using a nickel base of 4.0 tIm.

Using a bonding tool, adjust the temperature to 400.4
30.450℃, time 0.5.1.2 seconds, load 80
．． 100.120 g/lead and bonding conditions were changed and the semiconductor chips were bonded by heating and pressurizing and mounting the semiconductor chip.

In the obtained semiconductor device, there was no deformation such as bending of the leads of the copper pattern, and the shear strength between the leads and the chip was 5 g/l 000 under any setting conditions.
It was more than μ point and there was no problem in practical use.

(Comparative example) A 35 m wide 35 m thick electrolytic copper foil with a thickness of 35 m and a 75 m thick polyimide film with device holes and sprocket holes punched out are pasted together using epoxy adhesive.
The copper foil surface of the layered tape was patterned and plated with 0.5 μm of Ni and 1 μm of Au to create a conventional tape carrier.

Next, the gold bumps on the semiconductor chip and the leads protruding into the device holes of the tape carrier were heated at 400°C for 1 hour.
When the wires were connected by heating and pressurizing the wires under a load of 100 g/lead, defects such as bending of the leads were noticeable in some parts, and the yield was as low as 78%.

〔Effect of the invention〕

As described above, according to the method of the present invention, it is possible not only to overcome the conventional drawbacks of tape carrier type semiconductor devices, such as low yield and high cost, but also to overcome the narrow tolerance range of bonding conditions. This allows semiconductor chips to be mounted with extremely simple bonding conditions, resulting in high yields and low costs.
Moreover, it becomes possible to obtain a highly reliable semiconductor device.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a method for manufacturing a semiconductor device according to the present invention. FIG. 2 is a diagram showing a conventional method for manufacturing a tape carrier type semiconductor device without device holes.

Claims (1)

[Claims] (1) In a method for manufacturing a semiconductor device in which a semiconductor chip is mounted on a tape carrier having a circuit pattern formed of a conductor on a flexible insulating film, a conductor pattern with bumps formed at the tips of the leads is placed on the tape carrier. A method for manufacturing a semiconductor device, which comprises placing a tape carrier with a tape carrier on its side on a semiconductor chip on which bumps have been formed, aligning the same, and then bringing a bonding tool into contact with the insulating film side to apply heat and pressure.