JPS5929146B2 - Method for manufacturing substrates for semiconductor devices - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a substrate for a semiconductor device in the form of an insulating film having a thin conductor pattern.

In recent years, in order to reduce the size and weight of semiconductor devices used in watches, calculators, etc., polyimide packages with a pattern of conductor strips made of Cu or the like have replaced conventional semiconductor device packages using ceramic or metal frames. Flexible insulating film-like substrates made of resin or the like are often used.

Generally, this insulating film-like substrate (hereinafter referred to as carrier tape) is made of 11, 1
A slit with a constant width such as 8.35n is formed, and a sprocket hole 1a is formed at both ends, and a hole lb for bonding a semiconductor element such as an IC or LSI in the center and an external lead when using a semiconductor device. An insulating film 1 is provided with a hole lc for forming a portion of
It is composed of conductor strips 2 made of plated Cu or the like.

Further, the conductor strips 2 of this carrier tape are arranged in predetermined holes 1a, Ib, I as shown in the AA' cross-sectional view in FIG.
A conductive base 2a made of Cu or the like is bonded onto the insulating film 1 formed with c, and a plating layer 2 of Au, S old solder or the like covers the surface of the conductive base 2a other than the part bonded to the insulating film 1.
It is formed from b. In the carrier tape configured in this way, a semiconductor element (not shown) such as an IC or LSI is bonded to the tip of the conductor strip 2 in the central hole lb portion by solder reflow, thermocompression bonding, etc., and that portion is bonded. Covered with resin or the like, the conductor strip 2 is cut at portions 3a and 3b, and the cut portion is used as an external input/output lead by being connected to a predetermined substrate (not shown) of a device such as a watch or a calculator.

However, in the carrier tape having the above structure, the conductor strip 2 has a diameter of 70 to 100, especially in the center hole Ib.
The conductor strips 2 must be patterned to have a width of about 1 tm, and therefore the thickness of the conductor strips 2 is about 35 μm.

For this reason, when the conductor strip 2 cut at the portions 3a and 3b is bonded to a predetermined substrate, its strength is weak and bends easily, so its width must be increased. In particular, when it comes to multi-terminal semiconductor devices, the shape tends to be large, which goes against the objective of miniaturization. SUMMARY OF THE INVENTION Accordingly, the present invention provides a method for manufacturing a substrate for a semiconductor device in which the necessary portions of the conductor strips are made thicker to increase the strength thereof, in order to solve the above-mentioned conventional drawbacks.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a semiconductor device substrate according to the present invention will be described in detail below with reference to the drawings. FIG. 3 is a cross-sectional view of essential parts showing an embodiment of a semiconductor device substrate formed by the method of manufacturing a semiconductor device substrate according to the present invention, particularly an insulating film-shaped semiconductor device substrate. Since the same symbols as in FIG. 2 are the same elements, their explanation will be omitted.

In the figure, the parts of the conductor base 2a on the insulating film 1 that require strength, that is, the conductor base 2a at the cut parts 3a and 3b, can be electrolytically plated with Ni or the like and are resistant to etching of the conductor base 2a. A metal layer 4 is deposited. In this case, the thickness t' of the conductor strip 5 formed by depositing the metal layer 4 such as Ni is the thickness t of the conventional conductor strip 2.
It is formed sufficiently thicker than the According to such a configuration, the conductor strip 5 has a thickness t at the cut portions 3a and 3b.
Since ' is thick (t'>t), sufficient strength can be obtained.

Therefore, even in a multi-terminal semiconductor device, practically sufficient strength can be obtained without increasing the size of the device, and the semiconductor device can be miniaturized. Next, a method of manufacturing the above-mentioned insulating film-shaped substrate for a semiconductor device will be explained using cross-sectional process diagrams shown in FIGS. 4a-h.

First, as shown in Figure a, a sprocket hole 1a1 is slit to a predetermined width, central holes 1b and 1c are provided, and a Cu foil 6 with a thickness of about 35 μm is placed on the upper surface of an insulating film 1 made of polyimide or the like. Paste. Next, as shown in FIG.
Organic material films 7A, 7b, having plating liquid resistance such as photoresist are placed at predetermined positions on the surface portions of portions b and 1c.
7c, and a predetermined pattern of conductive strips is printed on the surface of the Cu foil 6. Next, as shown in FIG. 4c, Ni plating is applied to a thickness of several μm by electrolytic plating on the conductor strip patterns that are not covered with the organic material films 7A, 7b, and 7c to form a Ni layer 8. Next, figure d
As shown in FIG. 3, a region 8a of the Ni layer 8 excluding the part where the thickness of the strips is desired to be thickened on the surface of the Nl layer 8 is coated with a plating-resistant organic material film 9 such as photoresist; The region 8b of the Ni layer 8 that is not covered with the film 9 is coated with N! to a thickness of several μm to several tens of μm. Plating is applied to form a Ni layer 10 {see e in the same figure}. After that, as shown in FIG.
After removing c, an organic material film 7 is placed only in the holes 1b and 1c.
Recoat B, 7c. Next, the portions of the Cu foil 6 that are not covered by the surface Ni layers 8, 10 and the organic material films 7B, 7c are removed by etching to form a conductive base 2a of Cu foil, and then the organic material films 7B, 7c are removed. {(See g in the same figure)}. Thereafter, as shown in FIG.
A plating layer 2b of Au or the like is formed by electrolysis or electrolysis to form conductor strips 5 as shown in FIG. As explained above, in the method of manufacturing a substrate for a semiconductor device according to the present invention, the bridging portion of the hole of the conductor strip is locally formed thick, and the portion is cut to form a predetermined substrate. When bonded, its strength becomes extremely high.

Therefore, even in a multi-terminal semiconductor device, its shape can be reduced, and excellent effects such as miniaturization of the device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view of essential parts showing an example of a conventional semiconductor device substrate, particularly a carrier tape, FIG. 2 is a cross-sectional view taken along line A-A' in FIG. 1, and FIG. 3 is a cross-sectional view of a semiconductor device substrate according to the present invention. FIGS. 4A to 4H are cross-sectional views of main parts showing one embodiment of a semiconductor device substrate formed by the manufacturing method, and FIGS. . 1...Insulating film, 1a, 1b, 1c...・
．． ．． QLl2... Conductor strip, 2a...
Conductor base, 2b... Plating layer, 3a, 3b...
... Cutting part, 4 ... Metal layer, 5 ...
・Conductor strips, 6...Foil, 7a, 7b, 7c...
...Organic material film, 8...Ni layer, 9
...Organic material film, 10...Ni
layer.

Claims (1)

[Claims] 1. A flexible insulating film having a hole in the center for connecting and arranging a semiconductor element and a hole in the outer periphery of the hole to form a part that will become an external lead, and a flexible insulating film that bridges the outer peripheral hole and is on the insulating film. In the substrate for a semiconductor device, the conductor strip is electrolytically plated with a metal that can be electrolytically plated onto the conductor strip base and is resistant to etching of the conductor base. A method of manufacturing a substrate for a semiconductor device, characterized by forming a thick film.