JPH0653384A - Continuous manufacturing apparatus of lead frame - Google Patents

Abstract

(57) [Summary] (Corrected) [Purpose] A photoresist film is firmly attached to a thin metal plate on which a part of the lead pattern is formed, and the remaining lead pattern is formed by etching with high accuracy. Manufacturing equipment that can continuously perform operations such as plating. [Structure] A press for narrowing a part of the lead pattern,
A washing / drying device provided on the press's threading line, a photoresist film sticking device provided with a rotatably driven and braking device, a support roll facing the device, and the remaining lead pattern printed on the photoresist film. Positioning image processing device, device for baking and developing lead pattern and etching, device 24 for plating on desired portion of lead frame, sticking device 25 for sticking tape to inner lead, inspection device 26, pad of lead frame This is a continuous lead frame manufacturing apparatus provided with a depressing device 27 for shaping a part and a cutting device 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous lead frame manufacturing apparatus for both pressing and etching.

[0002]

2. Description of the Related Art Lead frames, which are indispensable as a material for assembling semiconductor devices, are required to have a large number of pins with fine leads and a narrow interval in response to the recent trend toward higher functionality, higher integration and miniaturization of semiconductor devices. It

For example, a lead frame having 100 or more pins has been manufactured. As one of manufacturing a multi-pin lead frame, a method using both punching by a press and etching has been proposed. For example, Japanese Examined Patent Publication 3-666
Japanese Patent Publication No. 3 discloses a method of manufacturing a lead frame in which the inner lead portion and the pad portion are formed by etching and the outer lead portion is formed by pressing. According to this, the advantages of both the fine etching action of etching and the high-speed and stable punching action by the press are obtained, and there is an effect that a lead frame with high processing accuracy can be manufactured at a relatively low cost.

[0004]

By the way, when a lead frame is manufactured by using both pressing and etching, a part of the lead pattern, for example, outer leads are punched by the press and the remaining lead patterns such as inner leads are formed. Is formed by etching. However, it is a problem that the yield is higher than that of the metal thin plate of the material, the lead patterns formed in the both steps are closely aligned with each other to have a good shape, and the manufacturing is performed with high productivity.

It is difficult to form press patterns and etching having different lead pattern forming mechanisms in a continuous line, while at the same time accurately aligning the remaining lead patterns with one part of the formed lead pattern. The reality is that there is no manufacturing equipment.

One of the reasons for this is that the photoresist coating causes unevenness and variations in the metal thin plate, and lead pattern formation by etching cannot be performed with good consistency.

There is a method of attaching a photoresist film to solve the above-mentioned coating problem. Although coating unevenness and the like are eliminated by this, since the photoresist film is soft and extremely thin, there are problems such as meandering, wrinkling, entrapment of air bubbles, and incompletely adhered portions when attached to a metal thin plate. After forming a part of the lead pattern with
The remaining lead pattern can be etched in a continuous line and cannot be aligned exactly.

The lead frame having the completed lead pattern is plated with a noble metal on the pad portion and the wire bonding portion of the inner lead. It is desirable to apply the plating only to the locally required parts from the viewpoint of cost reduction,
Poor consistency in the press and etching lead pattern formation causes a problem in plating.

According to the present invention, a thin metal plate on which a part of a lead pattern is formed by a press is formed without causing meandering, wrinkling, air bubbles and local adhesion failure even if the passing speed of the photoresist film is changed for some reason. An object of the present invention is to provide a continuous manufacturing apparatus capable of continuously attaching and forming the remaining lead patterns by etching with high precision, and continuously performing the subsequent plating, taping and depressing operations.

[0010]

SUMMARY OF THE INVENTION The gist of the present invention is a press for punching a part of a lead pattern on a thin metal plate, and a washing / drying device for the thin metal plate provided on a sheet passing line downstream of the press. A photoresist film sticking device provided in contact with a metal thin plate and provided with a braking device, a supporting roll provided with the metal thin plate sandwiched between the braking sticking device facing the braking device, and a sticking device attached to the metal thin plate. A positioning image processing device that prints the remaining lead pattern on the photoresist film, a device that prints and develops the lead pattern, a device that plating on the desired part of the lead frame where the lead pattern is completed, and a tape on the inner lead. A tape sticking device for sticking, an inspection device, a depressing device that pushes down or pushes up the pad portion of the lead frame, and a cover. In continuous production device of a lead frame, characterized in that a and winding devices. Further, it is in a continuous manufacturing apparatus in which a cutting device is provided in front of the plating device as required.

[0011]

According to the present invention, between the press for forming a part of the lead pattern and the etching production line for forming the remaining lead pattern, a washing / drying device for a thin metal plate and a driven rotation while being brought into contact with the thin metal plate and being braked. Then, a sticking device for sticking the photoresist film and a support roll are provided facing the sticking device with braking. Thus, the photoresist film tends to contract slightly while being unwound from the braking application device and applied to the cleaned thin metal plate. The resist film keeps a load state according to the winding tension, and the shrinkage phenomenon does not occur even when the sheet passing speed of the thin metal plate fluctuates, and it does not cause meandering, wrinkling, bubbles or defective adhesion and is continuous and exactly. Attached. As a result, the remaining lead pattern is formed on the part of the lead pattern previously formed by etching with good consistency on the continuous manufacturing line, and the subsequent partial plating and taping to predetermined portions of the lead frame are performed with high accuracy on the continuous line. Done.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings based on an embodiment. In the drawing, 1 is a press to form a part of a lead pattern, for example, an outer lead 3 as shown in FIG. Reference numeral 4 denotes an unwind reel that continuously feeds the thin metal plate 2. Reference numeral 5 is a leveler provided on the entrance side of the press 1, and 6 is a conveying roll. A cleaning / drying device 7 cleans the thin metal plate 2 with an alkali to remove adhered dirt and dry it. Reference numeral 8 is a loop that absorbs the difference in processing speed from the subsequent process and smooths continuous threading. In this embodiment, the loop 8 is provided at two places, but the present invention is not limited to this and may be provided as appropriate.

Denoted at 9 is a driven rotary sticking device with braking, which is attached with a photoresist film 10 attached to the thin metal plate 2 while being rotated while being driven, but the film 10 has a phenomenon of shrinking while being unwound and stuck, It is noted that this is a cause of occurrence of meandering, wrinkling, air bubbles, local sticking failure, etc., especially when the passing speed changes, and the prevention of this is the winding tension of the photoresist film 10 of the driven rotary sticking apparatus 9 concerned. It was found that it is good to apply an equal tension and unwind. A braking device 11 is attached to fulfill this. Guides 12 are provided on both sides of the driven rotary sticking device with braking 9,
The thin metal plate 2 passes between the guides 12 and the photoresist film 10 is attached.

Reference numeral 13 denotes a support roll, which is opposed to the driven rotary laminating apparatus 9 with braking and is rotatably driven by sandwiching the metal thin plate 2 therebetween. The burrs that were created in step 3 are corrected.

A similar driven rotary sticking device with braking 9-1 and a supporting roll 13-1 are provided rearwardly of the threading line of the driven rotary sticking device with braking 9 and the supporting roll 13 by changing the vertical arrangement. The photoresist film 10 is attached to the front and back surfaces of the thin plate 2.

Reference numeral 14 is a positioning image processing device for printing the lead pattern. For example, an image of the guide hole 15 formed in the thin metal plate 2 is imaged, and the pattern printing device 16 is positioned so as to be aligned with a predetermined pilot reference position. The carrier signal is output to a correction carrier device (not shown) for positioning.

A developing device 17 removes the photoresist film 10 other than the area exposed by the lead pattern printing to form an etching mask, for example, FIG. 4B.
The lead patterns of the inner leads 18, the pads 19, and the support bars 20 shown in FIG.

Reference numeral 22 denotes an etching device for injecting an etching solution onto the thin metal plate 2 to etch it, the inner lead 18 is aligned with the outer lead 3, and the pad 19, the support bar 20, and the tie bar 23 are formed with good alignment. , All patterns are completed as shown in FIG.

In this embodiment, the lead pattern formed by etching is the inner lead 18, the pad 19, and the support bar 20. However, the present invention is not limited to this. The inner lead tip portion, for example, the outer lead 3 is not limited to this. Alternatively, the pattern may be inward from the radial portion formed non-parallel to each other. In this case, a part of the inner lead 18 is formed by pressing.

A part of the outer leads 3, for example, the outer leads in the longitudinal direction of the metal thin plate 2 may be formed by pressing, and the other lead patterns may be formed by etching.

Reference numeral 24 is a predetermined portion of the lead frame having a lead pattern completed by a plating device, for example, a wire bonding scheduled portion at the tip of the inner lead 18 or the pad 1.
9 is plated with precious metals such as palladium, gold and platinum.
Reference numeral 25 denotes a tape sticking device for sticking an insulating tape to the middle portion of the inner lead 18 to prevent the tip end from fluctuating or deforming and facilitating the wire bonding work. 26
Is for inspecting the shape of the lead frame with an inspection device. A depressing device 27 pushes down the pad 19 portion to facilitate wire bonding between the chip (not shown) mounted on the pad 19 and the inner lead 18. In addition, the display device 27 uses the pad 19
May be pushed up and a heat dissipation plate or the like may be provided below it. A cutting device 28 cuts the lead frame every predetermined number. An apparatus for inspecting the shape or the like after depressing may be provided.

The second embodiment shown in FIG. 2 is provided with a cutting device 28 for cutting the thin metal plate 2 having the lead pattern completed before plating, into a predetermined number of lead frames, and plating with the cut plate lead frame. This is a manufacturing apparatus for performing the subsequent steps. The device configuration is the same as that of FIG. 1 except that the cutting device 28 is arranged in front of the plating device 24.

Reference numeral 29 denotes a photoresist coating device which is provided as needed, and which coats liquid photoresist on the end face of the thin metal plate 2.
If it is difficult to stick 0 to the end face,
This is effective when the lead frame product width is made equal in order to improve the extraction yield of the lead frame from the metal thin plate 2.

The structure of the apparatus is as described above. Next, the operation will be described. The thin metal plate 2 from the unwinding reel 4 is formed with the press 1 to form the outer leads 3 and the guide holes 15, and then washed and dried. Then, in order to form the remaining lead patterns such as the inner leads 18 by etching,
Subsequent rotary sticking devices with braking 9, 9-1 and support roll 1
The photoresist film 10 can be firmly attached to the metal thin plate 2 which passes between 3 and 13-1 without causing a shrinkage phenomenon, and does not cause meandering, wrinkling, and bubbles.

In order to print the remaining lead patterns such as the inner leads 19, pads 20, and support bars 21 on the thin metal plate 2 having the photoresist film 10 attached on both sides, a guide hole 15 is formed by the positioning image processing device 14.
Is detected at every intermittent conveyance interval, and the guide hole 15 is conveyed and printed so as to match the reference pilot of the pattern printing apparatus 16.

Subsequently, after development, a photoresist mask in which the patterns of the pads 19, support bars 20, and tie bars 23 including the inner leads 18 are aligned with the outer leads 3 previously formed is formed, and the remaining leads are etched. Complete the pattern by etching.

Then, the noble metal is plated on the portion of the lead frame pad 19 and the inner lead 18 where wire bonding is to be performed, or the thin metal plate 2 is cut into a strip shape every predetermined number of lead frames, and then the plating is performed. Next, for example, the intermediate portion of the inner lead 18 is taped with an insulating tape, the shape and the presence or absence of a short circuit are inspected, and then the depressing for pushing down the pad 19 is performed. If the cutting is not performed before the plating, the cutting is performed after the depressing.

[0028]

According to the present invention, when a lead frame is manufactured in a continuous line by using a press and an etch together, the metal thin plate having a part of the lead pattern formed by the press is washed and dried, and then contacted and rotated by rotation. Since a device with a brake for sticking the photoresist film is provided, it can be sticked in a continuous manner. In addition, the subsequent baking of the lead pattern can be done with good positioning accuracy, and the plating including the shape,
Both tape and depress can be performed well, and lead frames of excellent quality are produced in a continuous production line that combines pressing and etching.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a continuous manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing an outline of a continuous manufacturing apparatus according to another embodiment of the present invention.

FIG. 3 is a view showing an application device with a brake for a photoresist film according to an embodiment of the present invention.

FIG. 4 is a diagram showing manufacturing of a lead frame by using both pressing and etching in one embodiment of the present invention.

[Explanation of symbols]

 1 Press 2 Metal Thin Plate 3 Outer Lead 4 Unwinding Reel 5 Leveler 6 Conveyor Roll 7 Cleaning / Drying Device 8 Loop 9 Driven Rotating Laminating Device with Braking 10 Photoresist Film 11 Braking Device 12 Guide 13 Support Roll 14 Positioning Image Processing Device 15 Guide Hall 16 Pattern baking device 17 Imaging device 18 Inner lead 19 Pad 20 Support bar 21 Etching area 22 Etching device 23 Tie bar 24 Plating device 25 Tape sticking device 26 Inspection device 27 Depressing device 28 Cutting device 29 Photoresist device

Claims (2)

[Claims] 1. A press for punching a part of a lead pattern on a thin metal plate, a device for washing and drying the thin metal plate provided on a plate passing line downstream of the press, and a driven rotatable and braking device in contact with the thin metal plate. A device for attaching a photoresist film, a supporting roll provided opposite the braking device for sandwiching a thin metal plate, and a remaining lead pattern on the photoresist film attached to the thin metal plate. A positioning image processing device, a device for baking and developing a lead pattern, an etching device, a device for plating a desired portion of a lead frame with a completed lead pattern, a tape applying device for applying a tape to an inner lead, and an inspection device, A depressing device that pushes down or pushes up the pad portion of the lead frame, and a cutter that cuts the lead frame every predetermined number. An apparatus for continuously manufacturing a lead frame, comprising: 2. A press for punching a part of a lead pattern on a thin metal plate, a washing / drying device for the thin metal plate provided on a plate passing line downstream of the press, and a driven rotatable and braking device in contact with the thin metal plate. A device for attaching a photoresist film, a supporting roll provided opposite the braking device for sandwiching a thin metal plate, and a remaining lead pattern on the photoresist film attached to the thin metal plate. Positioning image processing device, a device for baking and developing a lead pattern, an etching device, a cutting device for cutting a thin metal plate having a completed lead pattern for each predetermined number of lead frames, and a device for plating a desired portion of the lead frame. The tape applying device that applies the tape to the inner lead, the inspection device, and the lead frame pad are pushed down or pushed up. And a lead frame continuous manufacturing apparatus.