JPH0385740A - Semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a semiconductor device by a tape carrier method high in yield rate, low in cost, and high in reliability by bringing a bonding tool into contact from the side of an insulating film and heating and pressurizing it so as to mount a semiconductor chip, and then injecting resin into the connection between the semiconductor chip and the lead of a conductor pattern and sealing it. CONSTITUTION:A slit 9 is formed at an insulating film between adjacent leads 4 in the vicinity of the lead top of a conductor pattern so as to manufacture a tape carrier 10. This tape carrier is placed, with the conductor pattern down, on a semiconductor chip 5, where a bump 6 is formed on the top side, and the positions of the bumps 6 on the chip and the ends of the leads 4 of the conductor pattern are aligned. Successively, the semiconductor chip 5 is connected to the conductor pattern while applying and pressurizing a bonding tool against it from the side of insulating film 1. Lastly, to protect the connection between the semiconductor chip 5 and the lead of conductor pattern, resin 8 is poured into it to seal the chip 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor device in which a semiconductor chip is mounted on a tape carrier and sealed with resin.

[Conventional technology]

In recent years, tape carrier systems have been viewed as promising for devices using semiconductors, such as displays and electronic computers, because they are smaller, thinner, and more dense.

However, conventional tape carriers have the drawbacks of complicated processes because they require forming leads that protrude into device holes, poor yields due to unstable leads deformation, and extremely high costs. .

In order to solve these problems, the present inventors have invented and disclosed a method for mounting a semiconductor chip without first forming leads protruding into device holes. Figure 3 shows this method. First, the insulating film (1) and the conductor (
A semiconductor chip (5) having bumps (6) formed on its upper surface is aligned face-down to a conductive pattern formed on a flexible substrate made by bonding 2) with an adhesive (3). After that, the bonding tool (17) is brought into contact with the insulating film side, and the connection part of the lead tip of the conductive pattern and the bump (6) on the semiconductor chip are heated and pressurized through the insulating film (1). The semiconductor chip (5) is mounted using the following steps.

Finally, in order to protect the connection between the semiconductor chip (5) and the leads of the conductor pattern, resin (8) is injected through the opening (7) and sealed, as shown in FIG. A tape carrier type semiconductor device is completed. With this method, there is no need to form leads that protrude into the device hole, so there are fewer steps, and there are no defects caused by deformation of the conductor leads that protrude into the device hole, resulting in high yields and low costs. Moreover, the connection part was characterized by high reliability.

However, resin-sealed products are subjected to high-temperature testing (HHT).
), saturated humidity test (PCT), heat stress test (T/
C) etc., the linear expansion coefficient and
It has been found that defects such as cracks in the resin (8) and disconnection of the leads (4) of the conductor pattern occur due to differences in humidity expansion coefficients. A possible solution to this problem is to control the linear expansion coefficient and humidity expansion coefficient of the encapsulating resin and insulating film, but since the characteristics of the copper foil and semiconductor chips cannot be changed, they are effective in reducing defects. However, it was not a fundamental solution.

[Problem to be solved by the invention]

The present invention was made 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 type semiconductor with high yield, low cost, and high reliability. The goal is to provide equipment.

[Means to solve the problem]

That is, the present invention provides 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, in which insulation between adjacent leads near the lead tips of the conductor pattern is improved. A tape carrier with a conductive pattern facing downward is placed on a semiconductor chip having a slit formed in at least one force position of the insulating film and bumps formed on the upper surface, aligned, and a slit is formed from the insulating film side. This is a semiconductor device characterized in that a semiconductor chip is mounted by bringing a bonding tool into contact and applying heat and pressure, and then a resin is injected into the connection portion between the semiconductor chip and the lead of the conductive pattern to seal it.

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

FIG. 1 is a diagram showing a tape carrier before mounting a semiconductor chip according to the present invention, and FIG. 2 is a sectional view of a completed product in which a semiconductor chip is mounted and resin-sealed. Insulating film (
Plating is applied to the surface of the lead of the conductor (2) pattern formed by a method such as photoetching on a flexible substrate in which the conductor (1) and the conductor (2) are bonded together with an adhesive (3), and then, Using a punching press or the like, slits (9) are formed in the insulating film (1) between adjacent leads in the vicinity of the lead tips of the conductive pattern to produce a tape carrier (10) as shown in FIG.

With the conductor pattern of this tape carrier facing down, place it on top of the semiconductor chip (5) with bumps (6) formed on the top side, and connect the bumps (6) on the chip and the tips of the leads of the conductor pattern. Align with. Next, as shown in Figure 3, insert the bonding tool (
17) and connect the semiconductor chip (5) to the conductor pattern while pressing. Finally, a resin (8) is poured and sealed to protect the connection portions between the semiconductor chip (5) and the leads of the conductive pattern (2), thereby completing the semiconductor device as shown in FIG. 2.

In this way, in the present invention, adjacent conductor patterns (2)
The feature is that a slit (-f+) is provided near the tip of the lead, and with this structure, the sealing resin (8), the conductor (2), the insulating film (1), the semiconductor It is possible to absorb the stress caused by the difference in the coefficient of linear expansion and the coefficient of humidity expansion of the chip (5), and it is possible to prevent defects such as cranking of the resin and breakage of the leads.

In addition, when performing resin sealing in the present invention, the inside part surrounded by the leads of the conductor pattern is sealed so that the resin gets into every corner between the semiconductor chip (5) and the insulating film (1). By providing an opening (7) and pouring resin through this hole, it becomes possible to obtain a more reliable semiconductor device.

The method of forming the slits (9) in the present invention is not particularly limited, but in terms of cost, it is preferable to use press punching, and when the pitch of the leads becomes finer, use laser processing.

In addition, the insulating film (1,) used in the present invention
The laminate of the conductor (2) and the conductor (2) is not specified in any way as long as it is normally used as a flexible printed circuit board, but since it is heated and pressurized through the insulating film (1), it has an insulating property. It is desirable that the 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 garnishing, sputtering, or plating, or an insulating resin such as epoxy resin or polyimide resin is applied on the metal foil and dried. The resulting two-layer laminate that does not use an adhesive provides better results because there are fewer layers that reduce heat resistance or block heat during heating and pressing with a bonding tool.

The surface of the conductive pattern is plated, and its type, thickness, and groove bottom are not particularly limited, but gold, tin, solder, etc. are generally used to match the bumps (6) on the semiconductor chip (5). Those used are preferred.

Further, the sealing resin (8) is not particularly limited as long as it is generally used for sealing semiconductors, but a liquid epoxy resin with high moisture resistance is desirable.

The bonding tool (17) used in the method of the present invention may be a commonly used bonding tool that can heat and press 200 g/lead or more at 600°C for 11 seconds and has a parallelism with the semiconductor chip of 5 μm or less. It is not particularly limited.

As described above, the present invention solves the problems of cranking and breakage of leads after resin sealing, which have been problems in film carrier type semiconductor devices with a new structure that does not require leads protruding into device holes. It is possible to obtain a film carrier type semiconductor device with high yield, low cost, and high reliability.

A comparative example between an embodiment of the present invention and a conventional method will be shown below.

〔Example〕

A 25-μm-thick insulating layer was formed by coating a 35-μm-thick electrolytic copper foil with a polyimide resin and drying it to obtain a two-layered laminate. This was slit into a tape shape with a width of 35 mm, the copper foil surface was patterned by etching, and the surface was plated with 0.3 μm of gold with a nickel base of 5.0 μm. Next, a slit was formed at the tip of the lead of the copper pattern by press punching, and an opening smaller in area than the area surrounded by the electrode on the semiconductor chip was made.

Next, the connection gold bumps formed on the semiconductor chip and the tips of the copper pattern leads of the tape carrier were aligned, and heated at 430°C for 11,5 seconds using a bonding tool through the polyimide resin insulating layer. , load 120
The semiconductor chip was mounted by heating and pressurizing and bonding with g/lead. Furthermore, liquid epoxy resin was injected through the opening provided in the BORIID insulating layer and cured at 100°C for 13 hours.

When the obtained semiconductor device was subjected to an environmental test, HHT (8
5°C 185%) 1500 hours, PCT (121'C,
100%) 300 hours, T/C (55°C, 125°C
) After 300 hours, no defects such as cracks in the sealing resin or breakage of the leads occurred.

[Comparative example]

A tape carrier type semiconductor device having the same configuration as the example except that the slit was not formed was fabricated and the same environmental test was conducted.
26% defects occurred at CT 100 hours and 24% defects occurred at T/C 200 hours.

[Effects of the Invention] As described above, according to the present invention, problems such as cracks in the sealing resin and disconnection of the leads of the conductor pattern, which are disadvantages of tape carrier type semiconductor devices without leads protruding into device holes, can be avoided. As a result, it becomes possible to obtain a semiconductor device with high yield, low cost, and high reliability.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a tape carrier before mounting a semiconductor chip according to the present invention, Fig. 2 is a cross-sectional view of a finished product with a semiconductor chip mounted and resin-sealed, and Fig. 3 is a diagram showing a tape carrier before mounting a semiconductor chip according to the present invention. FIG. 3 is a diagram showing a mounting method.

Claims (1)

[Claims] (1) In 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, an insulating film is formed between adjacent leads near the lead tips of the conductor pattern. A tape carrier with a conductor pattern facing down is placed on a semiconductor chip having a slit in at least one location and bumps formed on the upper surface, aligned, and a bonding tool is inserted from the insulating film side. 1. A semiconductor device characterized in that a semiconductor chip is mounted by bringing the semiconductor chip into contact with the leads under heat and pressure, and then a resin is injected into a connection portion between the semiconductor chip and a lead of a conductive pattern to seal it.