JPH02230608A - Raw material for tab tape and tab tape - Google Patents

Abstract

PURPOSE:To obtain a tape for TAB with a little expansion and contraction by providing a polyimide film in one surface, at least, of a copper foil, and providing wiring in a surface corresponding to the copper foil of the polyimide film. CONSTITUTION:The adhesive 2 is coated on both surfaces of a copper foil 1, and a hole a little larger than a semiconductor element is opened in the central part, and the copper foil 1 having the predetermined width is bonded on it. Photoetching is performed on the copper foil, and a wiring pattern is formed so that finger leads project open-sidedly from the hole. Al and covar can be used as a substitute for copper foil. Other insulating resin can be used as a substitute for polyimide. With this structure, the thermal shrink is remarkably reduced, and the stress to leads caused by the thermal shrink of a film is reduced after bonding, and the deformation of leads can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a new TAB tape material with low elasticity and a TAB tape.

[Prior Art] Normally, TAB tape is made by bonding a 35 μm thick copper foil to a polyimide film 1 having an opening and having a thickness of about 125 μm, and photo-etching this copper foil to form a wiring pattern. ．． The finger lead portion of this wiring pattern overhangs the opening in a cantilevered manner, and in use, the tip of the finger lead is heat-pressed to the electrode portion of the semiconductor element. At this time, the polyimide film shrinks slightly. This shrinkage rate is, for example, TA only for Kapton H (manufactured by DuPont), which is a commercially available polyimide film.
When used as a material for B tape, it has a temperature of 0.
07χ, 0 at 200°C, 13χ, 250
°C Te0.22 Z Te%ri, 300°c Teo. 3
Z, and only Corbilex SS (manufactured by Ube Industries) is T.
150°C T when used as material for AB tape
O. 03 Z Te, 200°C Te 0.06 Z, 250°C 0.08χ, 300°C 0
．． It is 2z. In this way, when only polyimide film is used as the material for TAB tape, the shrinkage rate is O. Although it is only n% or less, it becomes an important problem for the electrode part of a semiconductor device of about 100 x 100 μm. For example, 13
On one side of the semiconductor element of X 13 a++a, the width is approximately 1
If 100 00 μm electrodes are lined up at a pitch of 125 μm, a cumulative error of about 40 μm per side will occur at a shrinkage rate of 0.3%. In such a case, one side of the semiconductor element! This is because if the pole center is aligned with the center of the finger lead, the electrode at the other end will protrude from the tip of the corresponding finger lead, and as a result, it will be difficult to apply the TAB method.

[Problems to be solved by the invention] The present invention solves the above problems and provides a new TA with less expansion and contraction.
The present invention provides a B tape material and a TAB tape using the same.

[Means for Solving the Problems] The method of the present invention for solving the above problems is a TAB tape material having a polyimide film on at least one side of a copper foil, and a material for a TAB tape having a polyimide film on at least one side of the copper foil. , is a TAB tape having a wiring pattern on the surface facing the copper foil of the polyimide film.

[Effect] The present invention will be explained below using an example of implementation.

FIG. 1 shows an example of the implementation of the TAB tape of the present invention, which includes a TAB tape material 4 consisting of a copper foil 1, a polyimide film 3 adhered to both sides with an adhesive 2, and the material. In the device hole 5 opened in the center of 4,
FIG. 2 is a cross-sectional view of a TAB tape consisting of a wiring pattern 7 with finger leads 6 extending in a cantilevered manner, and FIG. 2 is a plan view of the TAB tape. When manufacturing this TAB tape, adhesive was applied to both sides of a copper foil with a width of 35 mm and a thickness of 35 μm at approximately 20 μI.
A TA. Apply approximately 20 μm of adhesive to one side of the B-table material, make a device hole slightly larger than the semiconductor element in the center, and place a 2-width device hole on top of it.
A 6 mm thick, 35 μm thick copper foil is bonded, and the copper foil is photo-etched to form a desired wiring pattern so that the finger leads cantilever out from the device hole. In the present invention, the polyimide film is bonded to at least one side of the copper foil in order to suppress heat shrinkage of the polyimide film by the copper foil and to reduce heat shrinkage of the TAB tape material itself. Therefore, it is desirable to change the thickness of the copper foil used depending on the degree of heat shrinkage of the polyimide film.17 The TAB tape material of this example is a copper foil with polyimide films bonded to both sides. is insulated, but if you do not need insulation on both sides, you can bond a polyimide film to only one side of the copper foil. In addition, TA. When creating a B-tape, pattern-forming copper foils may be bonded to both sides of the TAB tape material, and patterned using these to form a wiring pattern. Furthermore, the device hole of the TAB tape in the above embodiment was provided to facilitate alignment of the electrode on the semiconductor element and the tip of the finger lead when bonding, and is not necessarily required. It is also possible to use AI, Kover, 42 alloy, etc. instead of copper foil, and it is also possible to use other insulating resin films instead of polyimide film.

[Example-11 20 Jl was applied to both sides of silver foil with a width of 35 mm and a thickness of 35 μm.
An adhesive was applied to the adhesive to a thickness of m, and a 25 micron thick polyimide film (Kobi I/Tux S manufactured by Ube Industries, Ltd.) was laminated thereon to obtain a material for a TAB tape. This material was pressed, device holes for finger lead formation were opened, and copper foil for pattern formation with a width of 26.4 a+m and a thickness of 35 nm was pasted. Next, the lead width is 50
A pattern with a lead pitch of 125 and 11 nodes and a length of 2 mm was placed on each side of the device hole with 100 leads, patterned, and etched to form a pattern to form a TAB tape. Note that the lead pitch of this TAB tape is 12.375 mm.

This TAB tape at 150, 200, 250, 300°
Each lead was heated on a hot brake for 1 hour at C, and the difference in the total pitch of the lead before and after heating was taken as the amount of shrinkage. The obtained results are 0.01 z at 150°C and 0 at 200°C.
．． 01 z, 250 "C"C: 0.04 z, 30
The shrinkage rate is 0°C, 0.09Z, and has been reduced to less than half that of conventional polyimide film alone. [Effects of the Invention] According to the method of the present invention, the thermal shrinkage of the TAB tape material can be significantly reduced, resulting in the following advantages. Excellent dimensional stability can be obtained against various thermal histories during the TAB assembly process. Stress caused by film heat and shrinkage on the leads after bonding can be reduced, preventing deformation of the leads and reducing the protrusion of the leads into device holes.

[Brief explanation of the drawing]

FIG. 1 shows a cross-sectional view of one embodiment of the TAB tape of the present invention, and FIG. 2 is a plan view of the TAB tape. 4---T A B tape material 5-11 Device hole 6-11 Finger lead 7-11 Wiring pattern

Claims (1)

[Claims] 1. Material for TAB tape having a polyimide film on at least one side of the copper foil 2. Having a polyimide film on at least one side of the copper foil, and having a wiring pattern on the surface of the polyimide film facing the copper foil TAB tape