JP2748759B2 - Method of manufacturing film carrier tape - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a film carrier tape.

[0002]

2. Description of the Related Art As shown in FIG. 6, a conventional semiconductor device based on a film carrier system has an insulating film 6 made of polyimide or the like having a sprocket hole 1 for transporting and positioning and a device hole 17 into which a semiconductor chip 2 enters. A metal foil such as copper is adhered to the film carrier tape, and the metal foil is selectively etched to form a lead 4 having a desired shape and a pad 5 for electrical selection. The semiconductor chip 2 provided with the bumps 7 is prepared, and then the leads 4 of the film carrier tape and the bumps 7 of the semiconductor chip are subjected to inner lead bonding by a thermocompression bonding method or a eutectic method, and the film carrier tape is formed. In the state described above, a contact is brought into contact with the electric selection pad 5 to perform an electric selection and a bias test. Cut of the length.

[0003] Next, as shown in FIG.
The semiconductor chip 2 is fixed thereon with an adhesive 9 and the leads 4
To the bonding pads on the printed circuit board 8 by outer lead bonding.

[0004] Such a semiconductor device using the film carrier system can be bonded at once regardless of the number of leads, so that the speed is high. Since a film carrier tape is used, assembly such as bonding and electric sorting work are performed. It has advantages such as automation and excellent mass productivity.

[0005]

The conventional film carrier semiconductor device described above has a drawback in that it is necessary to form bumps on the electrodes of a semiconductor chip, and if bumps are formed by electroplating in a wafer state, the cost increases. There is. Several bump forming methods are introduced to solve this. For example, Solid State Technology (Solid State Technology)
ogy) A film carrier tape with a bump (hereinafter referred to as B-Tape) introduced in the Japanese version, November 1978, pages 33 to 35, National Technical Report (National Technical Report)
Report) 1985, Vol. 31, No. 3, 116
-Transfer bumps introduced on page 124 or
There is a method of using metal balls as bumps in wire bonding (hereinafter referred to as ball bumps) disclosed in Japanese Patent Application Laid-Open No. 4-2662 and Japanese Patent Application Laid-Open No. Sho 60-194543.

[0006] Of these, B-Tape is one in which the other lead portion is half-etched while leaving the lead end portion of the film carrier tape, and the lead end portion left in a convex shape without being half-etched is used as a bump. However, in order to half-etch a part of the lead, it is necessary to pattern and etch both surfaces of the metal foil, respectively. Therefore, each lead is electrically connected, and it has a drawback that it is difficult to electrically sort in a film carrier tape state. In order to solve this problem, it is possible to similarly form bumps on leads formed on an insulating film as in the related art, but there is a disadvantage that the process becomes complicated and conversely the cost increases.

The transfer bump is a method in which a bump is formed on a substrate such as glass by an electroplating method, the lead of a film carrier tape is bonded, and the bump is transferred from the substrate to the lead. And the need for bonding for transfer to the lead, etc., has many advantages in terms of cost as compared with the conventional bump formation method in a wafer state, but is not perfect.

A ball bump is formed by bonding only a metal ball to be formed on a semiconductor chip electrode during thermocompression wire bonding to form a bump. At the time of forming a bump and bonding a lead of a film carrier tape to the bump. Since the thermal and mechanical stresses are applied to the electrodes of the semiconductor chip twice, the electrode portion is easily broken and the reliability is poor.

[0009]

According to a method of manufacturing a film carrier tape of the present invention, a step of arranging and forming a lead made of metal on an insulating film, and forming a lead at a predetermined position of the lead on a tip of a thin metal wire. Forming a bump by separating the metal ball from the fine metal wire after bonding the formed metal ball, and selectively removing the insulating film by etching to form an inner lead opening and an outer lead opening. Film cap
In the method for manufacturing a rear tape,
The lead fixing insulating film is
The inside of the hole is formed by sandwiching the bump.
Separate from the end of the opening for the knurled lead.
An opening for stopping is provided, and at least the tip of the lead is provided.
It is characterized by being formed in a shape covering the end.

[0010]

Next, the present invention will be described with reference to the drawings.

FIGS. 1A and 1B are plan views showing a first embodiment of the present invention in the order of steps, and FIGS.
(A), (b) is a schematic sectional view of FIG. 1 (a), (b).

First, as shown in FIGS. 1 (a) and 2 (a), a lead 4 patterned into a desired shape and a pad 5 for electric sorting are provided on an insulating film 6 provided with a sprocket hole 1. A bump 7 made of a metal ball is formed at a predetermined position on the lead 4.

Next, as shown in FIGS. 1 (b) and 2 (b), the insulating film 6 is selectively etched to form an outer lead opening 14, an inner lead opening 3, and a resin seal. The stopper opening 15 is formed to form a film carrier tape.

FIGS. 3 (a) to 3 (c) show a flowchart related to the present invention.
FIG. 4 is a cross-sectional view illustrating a method of forming a bump of the film carrier tape in the order of steps.

As shown in FIG. 3A, a thin metal layer such as copper is formed on an insulating film 6 such as polyimide which can be etched by electroless plating or vapor deposition. A photoresist film is selectively provided, a metal layer is used as an electrode, a metal such as copper is electroplated using the photoresist film as a mask to form a metal layer having a thickness of about 35 μm, and then the whole is lightly etched. The lead 4 is formed by removing an unnecessary portion of the thin metal layer. Next, the surface of the lead 4 is plated with gold, tin or solder. Next, a thin metal wire 10 of gold, silver, copper, aluminum, etc.
The metal ball 11 is formed at the tip of the substrate by electric discharge or hydrogen flame.

Next, as shown in FIG. 3B, the metal ball 11 is connected to a predetermined position of the lead 4 by a connecting means such as a thermocompression bonding method or an ultrasonic compression bonding method.

Next, as shown in FIG. 3 (c), the metal thin wire 10 is cut at the joint with the metal ball 11 by lifting while holding the metal thin wire 10 by the clamp 12, thereby obtaining a desired bump 7.

Here, in order to improve the bonding property, the lead of the bump forming portion is plated with a metal suitable for bonding such as gold or silver, and the other portions are improved in the mountability of the semiconductor device. It is also possible to selectively perform plating of solder or the like in advance. Even when plating is performed, since the leads are fixed to the insulating film, selective plating can be performed without causing problems such as deformation of the leads during masking in selective plating.

FIGS. 4A and 4B are a plan view and a schematic sectional view showing an application example of the present invention.

As shown in FIGS. 4A and 4B, after the electrodes of the semiconductor chip 2 are aligned with the bumps 7 using the film carrier tape of the present invention, the opening 3 for the inner lead is formed. The bonding is performed by pressing the heating tool through the opening, and then the sealing resin 16 is dropped and cured in the resin sealing opening 15 to form a film carrier semiconductor device.

FIGS. 5A to 5D are sectional views shown in the order of steps for explaining a second embodiment of the present invention.

As shown in FIG. 5A, similarly to the first embodiment, the leads 4 and the pads for electrical selection are formed on an insulating film 6 such as polyimide, which can be etched.

Next, as shown in FIG. 5B, the insulating film 6 is selectively etched to form the outer lead opening 1.
4 is formed and plated with gold, tin, solder or the like. Here, similarly to the first embodiment, plating by changing the plating type of the inner lead portion and the outer lead portion can be easily performed by a mechanical masking method or a photoresist method.

Next, as shown in FIG. 5C, a metal ball is pressed to a predetermined position of the lead 4 by a thermocompression wire bonding method to form a bump 7.

Next, as shown in FIG. 5 (d), the insulating film 6 is selectively etched to form the inner lead opening 3, thereby forming a film carrier tape. In this embodiment, since plating is performed after forming the outer lead opening portion 14, a plating layer is formed on the entire surface of the outer lead, and the film carrier semiconductor device to which the semiconductor chip is bonded is mounted in both directions. It has the advantage of being able to.

In each of the first and second embodiments, the metal ball 11 can be press-bonded to the lead 4 while the tip of the lead is supported by the insulating film 6. There is no lifting of the lead when disconnecting.

[0027]

As described above, according to the present invention, a metal ball in wire bonding is removed from an insulating film.
To form a bump by pressing on the film carrier tape.
A bump inside the inner lead hole
To leave an insulating film on the area including the lead tip.
Pressure bonding of semiconductor chip and bump on lead
The deformation of the inner lead at the time of performing can be avoided.

[0028]

[Brief description of the drawings]

FIG. 1 is a plan view illustrating a first embodiment of the present invention in a process order.

FIG. 2 is a schematic sectional view of FIG.

FIG. 3 is a perspective view of a film carrier tape related to the present invention.
Sectional drawing which showed the formation method of the pump in process order.

FIG. 4 is a plan view and a schematic cross-sectional view showing an example of using the film carrier tape of the present invention.

FIG. 5 is a sectional view shown in order of steps for explaining a second embodiment of the present invention.

FIG. 6 is a plan view showing an example of a conventional film carrier tape.

FIG. 7 is a sectional view showing an example of use of a conventional film carrier tape.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sprocket hole 2 Semiconductor chip 3 Inner lead opening 4 Lead 5 Sorting pad 6 Insulating film 7 Bump 8 Printed circuit board 9 Adhesive 10 Fine metal wire 11 Metal ball 12 Clamp 13 Discharge rod 14 Outer lead opening 15 Resin Sealing opening 16 Sealing resin 17 Device hole

Claims (1)

(57) [Claims] 1. A step of arranging and forming a lead made of metal on an insulating film, and bonding the metal ball formed at the tip of the thin metal wire to a predetermined position of the lead and separating the metal ball from the thin metal wire. forming a bump Te, the insulating film is selectively etched and removed and a step of forming an opening portion and an outer lead for opening inner leads film carrier tape
In the method of manufacturing a tape, a lead comprising the insulating film is provided.
The insulating film for fixing the lead is the opening for the inner lead.
The inner lead is sandwiched between the bumps inside the
Away from the edge of the opening for
And at least a tip of the lead is covered.
A method for producing a film carrier tape, characterized in that the film carrier tape is formed in a shape like a circle.