JPH0689920A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the size of a TAB chip without deteriorating the resistance of a lead against a mechanical stress caused by the difference in coefficient of thermal expansion between the TAB chip and a high-density board on which the chip is mounted. CONSTITUTION:In a TAB chip composed of an LSI chip 3 and a plurality of copper leads formed in a pattern from TAB tapes which are arranged around the chip 3 and constituted by sticking rolled copper plates to insulating tapes, the length of the TAB leads 5 elongated in the direction coincident with the rolling direction of the rolled copper plates is made longer than that of the TAB leads 4 elongated in the direction perpendicular to the rolling direction of the copper plates.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, in a semiconductor device of this type, a copper lead arranged around an LSI chip 3 has a length T extending in a direction coinciding with a rolling direction of a rolled copper plate.
The same applies to the AB lead 4a and the TAB lead 4a extending in the direction perpendicular to the rolling direction of the rolled copper sheet.

[0003]

In the conventional semiconductor device described above, the tensile strength of the rolled copper sheet forming the TAB tape of the TAB chip is the same as the rolling direction of the rolled copper sheet and the direction perpendicular to the rolling direction. Despite being different in
The length of the copper lead that absorbs the mechanical stress caused by the difference in thermal expansion coefficient between the TAB chip and the high-density substrate such as a printed circuit board or a ceramic substrate on which the AB chip is mounted has a weaker tensile strength. Since the length is increased to match the copper lead extending in the direction perpendicular to the rolling direction of TA,
There is a problem that the B chip becomes large and high-density mounting cannot be realized.

[0004]

The semiconductor device of the present invention comprises:
A TAB chip including an LSI chip and a plurality of copper leads formed around the LSI chip and patterned from a TAB tape having a rolled copper plate adhered on an insulating tape, the TAB chip extending in a direction corresponding to the rolling direction of the rolled copper plate. Lead and a copper lead extending in a direction perpendicular to the rolling direction of the rolled copper sheet, which is shorter than the lead.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIGS. 1A and 1B are a plan view and a sectional view showing an embodiment of the present invention. The TAB lead 4 connected to the LSI chip 3 is manufactured by patterning a TAB tape having a thin rolled copper plate adhered on an insulating tape to an arbitrary width by etching or the like. One end of the TAB lead 4 is connected to the LSI chip 1 via an inner lead bonding portion 6, and the other end is connected to an LSI chip 1 via an outer lead bonding portion 7 which is a high density substrate 8 made of a printed circuit board or a ceramic substrate. Are connected by a technique such as soldering. Further, the TAB lead 4 is generally bent near the outer lead bonding portion 7 by molding. Here, of the TAB leads 4, the length of the TAB lead 5 in the rolling direction, which extends in the direction coinciding with the rolling direction of the rolled copper sheet, is shorter than the other TAB leads 4.

Along with the rapid progress of downsizing and weight saving of OA devices in recent years, OA devices are becoming more portable, and the environment in which they are used has become extremely severe. For example, looking at the temperature of the device, there is a temperature difference of about 40 ° C. between the hot weather in summer and the air-conditioned room. On the other hand, if the ambient temperature of the TAB chip 1 and the high-density substrate 8 changes, the TAB
The temperatures of the chip 1 and the high-density substrate 8 also change, and mechanical stress due to the difference in thermal expansion coefficient between the TAB chip 1 and the high-density substrate 8 is applied to the TAB lead 4. Since the TAB lead 4 is made of a thin copper plate, it is relatively malleable, and since it has a bent portion that absorbs mechanical stress, it can withstand repeated repeated stress to some extent, but extreme temperature differences and If the repeated stress continues for a long time, the TAB lead 4 is broken. The disconnection of the TAB lead 4 is related to its width, thickness, length and tensile strength of the material,
In the TAB chip 4 having the same width and thickness, the length and the tensile strength of the material determine the strength of the TAB lead 4. The longer the length and the larger the tensile strength, the stronger the mechanical stress.

The rolled copper sheet used for the TAB lead 4 has a tensile strength in the rolling direction larger than that in the direction perpendicular to the rolling direction. Therefore, the TAB lead in the rolling direction extended in the rolling direction by the amount corresponding to the larger tensile strength. Even if the length of 5 is shortened, the strength of the ATB lead 4 in the TAB chip 1 as a whole does not change. Therefore, by shortening the length of the TAB lead 5 extending in the rolling direction,
The size of the chip 1 can be reduced, and high-density mounting can be realized. Also, the TAB lead 5 in the rolling direction
When the length of the TAB chip 1 is shortened, the TA
Although the lengths of the B leads 4 are different, there is no problem in manufacturing only by forming the molding / cutting mold in accordance with the length.

[0009]

As described above, according to the present invention, with respect to the lead length of the TAB chip, the length of the lead extending in the direction coinciding with the rolling direction of the rolled copper plate which is the material of the lead is shorter than the other leads. By doing so, there is an effect that the TAB chip can be downsized and high-density mounting can be realized.

[Brief description of drawings]

1A and 1B are a plan view and a cross-sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view showing a conventional example.

[Explanation of symbols]

 1 TAB Chip 2 TAB Chip 3 LSI Chip 4 TAB Lead 5 TAB Lead in Rolling Direction 6 Inner Lead Bonding Part 7 Outer Lead Bonding Part 8 High Density Substrate

Claims (1)

[Claims] 1. A TAB having an LSI chip and a rolled copper plate which is arranged around the LSI chip and is adhered onto an insulating tape.
In a semiconductor device having a TAB chip composed of a plurality of copper leads patterned from a tape, the length of the copper leads extending in a direction coinciding with the rolling direction of the rolled copper plate is a direction perpendicular to the rolling direction of the rolled copper plate. A semiconductor device characterized in that it is shorter than the length of the copper lead extended to.