JPH06333991A - Manufacture of film carrier - Google Patents

Abstract

PURPOSE:To remove such burrs as to become a hindrance in the lithography process at patterning or in positioning at I.L.B by diminishing burrs occurring at an opening or at the edge of a groove, using a cutting tool with a tapered peripheral edge. CONSTITUTION:The plastic deformation onto the surface of the tape of an organic insulator a, which occurs at the edge d of an aperture in cutting, is suppressed by making a taper e at the peripheral edge of the cutting tool. The manufacture of a film carrier substantially free of burrs become possible by suppressing the occurrence of large burrs by this action. For the taper angle thetaof the cutting tool, good result can be obtained at 30-80 deg.. Hereby, large burrs, which occur when using a conventional cutting tool, vanish, and a film carrier without a hindrance in lithography process at patterning or in positioning at I.L.B can be manufactured.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for manufacturing a film carrier for semiconductor assembly.

[0002]

2. Description of the Related Art In recent years, electronic devices have been made highly functional, light, thin, short and small, and the semiconductors mounted on them have been required to be highly integrated and highly functional, and their packages are also required to be small and thin. ing. In order to meet such demands, a mounting method by a TAB (Tape Automated Bonding) method using a film carrier is widely used. On the film carrier used in the TAB method, a film carrier having a two-layer structure consisting of only a metal conductor layer and an organic insulating layer, and a metal conductor layer and an organic insulating layer were attached via an adhesive layer.
There are layered film carriers.

In a film carrier having a three-layer structure, a mounting hole for a semiconductor element in an organic insulating layer, a lead hole for taking out a connection lead, and / or a positioning hole used for assembling and mounting an opening portion are formed in an organic layer. It has excellent productivity because it is formed by pressing at the stage where the adhesive is applied to the insulating layer and then the metal conductor layer is attached, but it takes days to manufacture the pressing die, and it also intervenes. There is a problem in that the heat resistance is lowered due to the adhesive agent and the reliability of the mounted semiconductor device is lacked due to the contained impurity chlorine ions. The film carrier having a two-layer structure is manufactured by an additive method or a casting method in a state where the metal conductor layer and the organic insulating layer are in close contact with each other,
Since there is no adhesive layer, it has excellent heat resistance and electrical characteristics and has higher reliability than the three-layer product. However, when forming the above-mentioned opening portion, it is necessary to remove the organic insulating layer in the opening portion while leaving the metal conductor layer, and therefore press working cannot be used.

Examples of the method of forming the openings include a wet etching method, a dry etching method, and / or a laser etching method. The wet etching method requires a lithography process, requires a long process, is inferior in economic efficiency, and has a problem that the material of the organic insulating layer is limited. As a dry etching method, a sputtering method and an ion milling method are known, but each requires an expensive and large-scale device, and further, continuous production is difficult, and there is a problem in economical efficiency, productivity, and workability. . In recent years, the laser etching method, which has been attracting attention, has problems that the conductor metal layer is melted and damaged by heat, and carbon that is difficult to remove is generated and adhered.

As a method for producing a film carrier having a two-layer structure which does not have the above problems, the inventors of the present invention invented the method for producing a hole portion formed by cutting as disclosed in JP-A-2-161740. There is a forming method. The formation of the opening by cutting is performed by a numerical control type processing machine with a small-diameter counterboring cutting tool attached to the spindle, and it is possible to manufacture a film carrier with a two-layer structure and various shapes of opening. Since the parts can be formed by programming the control device and a die for press is not required, it has an advantage in a small amount of trial manufacture and a short-term production even in the production of a film carrier having a three-layer structure. .

[0006]

When a cutting tool having a blade shape which is generally used for counterboring a printed circuit board or peripheral cutting is used as a cutting tool for a processing machine, the boundary between the opening and the opening is irrelevant regardless of the processing conditions. A large burr is formed on the upper part of the organic insulating layer forming the. This burr not only interferes with the lithography process at the time of patterning but also I.V. for mounting a semiconductor chip. L. B. (Inner Lead Bonding) has a problem of hindering alignment. In order to solve the above problems, as a result of examining the cutting tool to be used, it was found that burr can be suppressed by using a tapered outer peripheral blade in contact with the surface of the organic insulating layer when forming the opening. The present invention has been reached. The present invention has been made in view of such a background, and when manufacturing a film carrier having a two-layer structure and a film carrier having a three-layer structure by a cutting method, a lithographic step at the time of patterning, an I.D.
L. B. It is an object of the present invention to provide a method for manufacturing a film carrier that does not have burrs that may interfere with time alignment.

[0007]

The present invention has the following configurations (1) and (2). (1) In a method of manufacturing a film carrier having a two-layer structure including a metal conductor layer and an organic insulating layer, a mounting hole for a semiconductor element, a lead hole for taking out a connection lead, and / or a positioning hole used during assembly and mounting. A film characterized by reducing burrs generated at the edges of openings or grooves by using a cutting tool with a tapered outer peripheral edge when forming other openings or grooves by cutting. Carrier manufacturing method. (2) In a method for producing a film carrier having a three-layer structure in which a metal conductor layer and an organic insulating layer are bonded together with an adhesive, a mounting hole for a semiconductor element, a lead hole for taking out a connection lead, and / or By using a cutting tool with a tapered outer peripheral edge when forming holes or grooves such as positioning holes used during assembly and mounting by cutting, burrs that occur at the edges of holes and grooves are reduced. A method for manufacturing a film carrier, which comprises:

The structure and effect of the present invention will be described in detail below. The types of cutting tools used in the present invention are classified into the following two types depending on the position of the tapered portion. (1) A taper over the range to be cut from the cutting edge to the upper part of the organic insulating layer. (2) A taper is not applied from the cutting edge to the middle of the layer, but is tapered from the middle to the upper part of the organic insulating layer to be cut. The effects of suppressing burrs are the same, but the manufacturing of the cutting tool can be performed more easily in (1). An example of a cutting tool having a structure corresponding to the above (1) and (2) is shown in FIGS. 1 and 2. The figure shows the blade shape of the cutting tool and the cross-sectional shape when the two-layer tape is counterbored. The shape of this blade is not affected by the number of blades of the cutting tool and exhibits the same burr suppression effect. Also, since the cross-sectional shape of the side surface of the opening differs depending on the position and angle of the taper, use a cutting tool with a shape that conforms to the product standard, but a taper angle of 30 ° to 80 ° gives good results. To be

The method of using the cutting tool used in the present invention is the same as that of the cutting tool used up to now, and it is not necessary to change the holding method, the processing conditions and the like. The constituent material of the metal conductor layer is copper, aluminum, gold, silver, iron, tin,
Examples thereof include lead, alloys thereof, and those obtained by plating these. Polyimide resin, polyethylene terephthalate resin, glass reinforced epoxy resin and the like are typical examples of the organic insulating layer constituent material, but in addition to these, polybutylene terephthalate resin, polyparabanic acid resin, polyphenylsulfone resin, polyetherimide resin, polyether. Examples include ketone resins. Further, as an adhesive layer constituent material in the three-layer structure, an epoxy adhesive,
Examples thereof include polyimide adhesives, urethane adhesives, acrylic and methacrylic adhesives, isocyanate adhesives, and the like. As the constituent material of the blade of the cutting tool, HSS,
Cemented carbides, cermets, ceramics and those coated with titanium compounds, diamonds, etc., single crystal diamonds, sintered diamonds, etc. can be used, and all materials used for cutting tools can be used. .

[0010]

[Operation] By tapering the outer peripheral edge of the cutting tool,
Plastic deformation of the organic insulating material on the tape surface, which occurs at the edge of the hole during cutting, is suppressed, and the generation of large burrs is suppressed by this action, enabling the production of a film carrier having almost no burrs.

[0011]

EXAMPLE When manufacturing a film carrier having a two-layer structure,
An example of machining using the cutting tool according to the present invention will be introduced.
FIG. 3 shows a cross-sectional shape of an opening portion formed by a cutting tool having a taper angle of 45 °, and FIG. 4 shows a cross-sectional shape of an opening portion formed by a conventionally used cutting tool. In the cutting tool used conventionally, a large burr having a root thickness of 10 μm to 50 μm and a height of 10 μm or more to about 1 mm was generated at the edge of the hole, but using the tapered cutting tool of the present invention Thus, the size of the burr generated could be suppressed to 5 μm or less.

[0012]

Since the present invention is constructed as described above, it has the following effects. In the method of manufacturing a film carrier in which the organic insulating layer is cut and removed by a cutting machine to form device holes and the like, there is no large burr generated when a conventionally known cutting tool is used, and patterning can be performed. Lithography process and I.V. L. B. It is possible to manufacture a film carrier that does not hinder time alignment.

[Brief description of drawings]

FIG. 1 is an illustration of a structure of a cutting tool according to the present invention.

FIG. 2 is another example of the structure of the cutting tool according to the present invention.

FIG. 3 is a cross-sectional shape of an opening portion formed by the cutting tool according to the present invention.

FIG. 4 is a view showing an example of a cross-sectional shape of a burr that occurs when processed with a known cutting tool.

[Explanation of symbols]

 a organic insulating layer b metal conductor layer c opening part d opening part edge e taper part f burr g burr root thickness h burr height θ taper angle

Claims (2)

[Claims] 1. A method for producing a film carrier having a two-layer structure comprising a metal conductor layer and an organic insulating layer, which is used for mounting holes for semiconductor elements, lead holes for taking out leads for connection, and / or for assembly and mounting. When forming positioning holes and other openings or grooves by cutting,
A method for manufacturing a film carrier, characterized in that by using a cutting tool having a tapered outer peripheral edge, burrs generated at the edges of holes and grooves are reduced. 2. A method of manufacturing a film carrier having a three-layer structure in which a metal conductor layer and an organic insulating layer are bonded together by using an adhesive, a mounting hole for a semiconductor element, a lead hole for taking out a connection lead, And / or, when forming a positioning hole or other openings or grooves used during assembly and mounting by cutting, use a cutting tool with a tapered outer peripheral edge to allow burrs to occur at the edges of the openings or grooves. A method for producing a film carrier, which comprises reducing