JP3028160B2 - Lead frame continuous manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A lead frame, which is indispensable as an assembling material for a semiconductor device, is required to have a multi-pin structure with fine leads and narrow spaces in response to the recent advancement of functions, integration and size of the semiconductor device. You.

[0003] Lead frames of, for example, 100 pins or more have been manufactured, and as one of the manufacturing methods of a multi-pin lead frame, a method of using both punching by pressing and etching has been proposed. For example, Japanese Patent Publication 3-666
No. 3 discloses a method of manufacturing a lead frame in which an inner lead portion and a pad portion are formed by etching, and an outer lead portion is formed by pressing. According to this, both advantages of a fine etching action of etching and a high-speed and high-stability punching action by a press are obtained, and there is an effect that a lead frame with high processing accuracy can be manufactured relatively inexpensively.

[0004]

When a lead frame is manufactured by using both pressing and etching, a part of the lead pattern, for example, an outer lead is formed by pressing, and the remaining lead pattern such as an inner lead is formed. However, there is a problem that the yield is high from the metal thin plate of the raw material, the lead patterns formed in both steps are precisely aligned with each other, the shape is good and the productivity is high.

[0005] It is difficult to dispose presses and etchings having different lead pattern forming mechanisms on a continuous line, and to form the lead pattern formed partially by precisely matching the remaining lead pattern with the remaining lead pattern. The fact is that there is no manufacturing equipment.

One of the reasons is that the application of a photoresist causes unevenness or variation in a thin metal plate, and it is not possible to form a lead pattern by etching with good consistency.

As a method for solving the problem of the application, there is a method of attaching a photoresist film. This eliminates coating unevenness, but the photoresist film is soft and extremely thin, so there are problems such as meandering, wrinkling, entrapment of bubbles, and incomplete sticking at the time of sticking to a metal sheet. After forming a part of the lead pattern with
The remaining lead patterns cannot be etched and aligned in a continuous line.

[0008] The lead frame on which the lead pattern has been completed is plated with a noble metal on the pad portion and the wire bonding portion of the inner lead. It is desirable from the viewpoint of cost reduction that the plating is applied only to a locally required portion,
The poor matching in the press and etching lead pattern formation also causes problems in plating.

According to the present invention, a thin metal sheet on which a part of a lead pattern is formed by pressing can be formed without any meandering, wrinkling, bubbles and local adhesion failure even if the speed of passing the photoresist film changes for some reason. An object of the present invention is to provide a continuous manufacturing apparatus in which the remaining lead patterns are adhered to each other with high precision by etching and formed with high precision, and subsequent operations from plating, taping to depressing can be continuously performed.

[0010]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a press for punching a part of a lead pattern in a metal sheet, a cleaning / drying apparatus for the sheet metal provided downstream of the press, and baking and developing the lead pattern. And a device for plating a desired portion of a lead frame on which a lead pattern is formed, a tape attaching device for attaching a tape to inner leads, an inspection device, and a depressing device for pushing down or pushing up a pad portion of a lead frame. Equipment and a cutting device for cutting a predetermined number of lead frames are provided, and in a continuous lead frame manufacturing device manufactured by using both pressing and etching, a metal is provided between the cleaning / drying device and the etching device. A photoresist film sticking apparatus provided with a driven rotatable and braking device in contact with a thin plate; And a support roll provided opposite the thin metal plate, and a positioning image processing device for imaging a guide hole formed in the thin metal plate and outputting a positioning transport signal so as to match a pilot reference predetermined in a pattern printing apparatus. And a continuous manufacturing apparatus for a lead frame.

[0011]

According to the present invention, between a press for forming a part of a lead pattern and an etching production line for forming a remaining lead pattern, an apparatus for cleaning and drying a thin metal sheet, and a driven rotation while being braked against the thin metal sheet. An attaching device for attaching a photoresist film, and a support roll are provided to face the attaching device with braking. Thus, the photoresist film tends to slightly shrink while being unwound and affixed to the cleaned metal sheet from the affixing device with the braking device. The resist film is kept in a load state according to the winding tension, and even when the sheet passing speed of the metal sheet fluctuates, the shrinkage phenomenon does not occur, and meandering, wrinkling, air bubbles and poor adhesion are continuously and precisely generated. Affixed. As a result, the remaining lead pattern is formed on a part of the lead pattern formed earlier by etching with good consistency on a continuous manufacturing line, and then the partial plating and taping on a predetermined portion of the lead frame are accurately performed on the continuous line. Done.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on one embodiment with reference to the drawings. In the drawing, reference numeral 1 denotes a press for forming a part of a lead pattern, for example, an outer lead 3 as shown in FIG. Reference numeral 4 denotes an unwinding reel which continuously feeds the metal sheet 2. 5 is a leveler provided on the entry side of the press 1, and 6 is a transport roll. Reference numeral 7 denotes a washing / drying device for removing, for example, adhered dirt from the thin metal plate 2 by alkali washing and drying. Reference numeral 8 denotes a loop for absorbing a difference in processing speed from a subsequent process and smoothing a continuous sheet passing operation. In this embodiment, two loops 8 are provided. However, the present invention is not limited to this.

Reference numeral 9 denotes a driven rotating and sticking device with a brake. A photoresist film 10 is attached to the thin metal plate 2 and is adhered while being driven and rotated. The film 10 is unwound and shrinks while being attached. It is found that this is a cause of meandering, wrinkling, air bubbles, local sticking failure, etc., particularly when the passing speed changes, and in order to prevent this, the winding tension of the photoresist film 10 of the driven rotary sticking device 9 is reduced. It has been found that it is better to apply the same tension and unwind. A braking device 11 is provided to accomplish this. Guides 12 are provided on both sides of the driven rotation sticking device 9 with braking,
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 provided to be rotatable and rotatable with the thin metal plate 2 interposed therebetween, which is opposed to the driven rotary sticking device 9 with braking, assists the sticking of the photoresist film 10 and presses the thin metal plate 2 with the press 1. The burrs generated in the above are corrected.

Behind the passing line of the driven rotary sticking device 9 with brake and the support roll 13, a similar driven rotary sticking device 9-1 with support and a support roll 13-1 are provided with their upper and lower positions changed. A photoresist film 10 is attached to the front and back surfaces of the thin plate 2.

Reference numeral 14 denotes a positioning image processing device for printing a lead pattern. The positioning image processing device picks up an image of, for example, a guide hole 15 formed in the thin metal plate 2, and positions the pattern printing device 16 so as to match a pilot reference position which is predetermined. The transport signal is output to a correction transport device (not shown) to perform positioning.

Reference numeral 17 denotes a developing device, which removes the photoresist film 10 from a region other than a region exposed by baking a lead pattern to form an etching mask, for example, as shown in FIG.
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 etching and etching the thin metal plate 2 by spraying the same, the inner leads 18 are aligned with the outer leads 3, and the pads 19, the support bars 20, and the tie bars 23 are formed with good alignment. , All the patterns are completed as shown in FIG.

In this embodiment, the lead patterns formed by etching are the inner leads 18, the pads 19, and the support bars 20. However, the present invention is not limited to this, but is applied to not all of the inner leads 18 but the tip of the inner leads, for example, the outer leads 3. On the other hand, a pattern inside a radial portion formed non-parallel may be used. In this case, a part of the inner lead 18 is formed by pressing.

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

Reference numeral 24 denotes a predetermined portion of the lead frame on which the lead pattern has been completed by the plating apparatus, for example, a portion to be wire-bonded at the tip of the inner lead 18 or the pad
9 is plated with a noble metal such as palladium, gold, or platinum.
Numeral 25 denotes a tape sticking device, for example, in which an insulating tape is stuck to an intermediate portion of the inner lead 18 to prevent fluctuation or deformation of the tip portion and to facilitate wire bonding work. 26
The inspection device inspects the quality of the shape of the lead frame with an inspection device. Reference numeral 27 denotes a depressing device, which presses down the pad 19 to facilitate wire bonding between a chip (not shown) mounted on the pad 19 and the inner lead 18. Further, the pad 19 is
, And a heat radiating plate or the like may be provided below. Reference numeral 28 denotes a cutting device for cutting the lead frame at a predetermined number. Note that an apparatus for inspecting the shape and the like after depressing may be provided.

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

Reference numeral 29 denotes a photoresist coating device provided as needed, which applies a liquid photoresist to the end surface of the thin metal plate 2.
If it is difficult to attach 0 to the end face,
This is effective in making the lead frame product width equal to the lead frame product width in order to improve the yield of the lead frame from the metal sheet 2.

The configuration of the apparatus is as described above. Next, the operation will be described. The metal thin 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,
Driven rotation sticking devices 9 and 9-1 with braking and support roll 1
The photoresist film 10 can be stuck tightly without causing a shrinkage phenomenon, and does not meander, wrinkle, or generate air bubbles.

In order to print the remaining lead patterns, for example, the inner leads 19, the pads 20, and the support bars 21, on the metal thin plate 2 having the photoresist film 10 adhered on both sides thereof, the guide holes 15 are formed by the positioning image processing apparatus 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, development is performed to form a photoresist mask in which the patterns of the pad 19, the support bar 20, and the tie bar 23 are aligned with the inner lead 18 on the previously formed outer lead 3, and the remaining lead is etched. Complete the pattern by etching.

Next, the noble metal is plated on the pad 19 of the lead frame and the portion to be wire-bonded on the inner lead 18, or the metal thin plate 2 is cut into strips by a predetermined number of lead frames, and then the plating is performed. Next, for example, the middle portion of the inner lead 18 is taped with an insulating tape, the shape, the presence or absence of a short circuit, and the like are inspected. If the cutting is not performed before plating, the cutting is performed after depressing.

[0028]

According to the present invention, when a lead frame is manufactured in a continuous line by using both a press and an etch tag, the thin metal plate on which a part of the lead pattern is formed by the press is washed, dried, contacted and driven to rotate. Since a device with a brake for applying a photoresist film is provided, it is possible to apply the film exactly continuously. In addition, subsequent baking of the lead pattern can be performed with good positioning accuracy,
Lead frames of excellent quality can be produced with good quality for both tape and depress, and are manufactured on a continuous production line that combines press and etching.

[Brief description of the drawings]

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Press 2 Metal thin plate 3 Outer lead 4 Unwinding reel 5 Leveler 6 Conveying roll 7 Cleaning / drying device 8 Loop 9 Brake driven rotation sticking device 10 Photoresist film 11 Braking device 12 Guide 13 Support roll 14 Positioning image processing device 15 Guide Hole 16 Pattern baking device 17 Developing device 18 Inner lead 19 Pad 20 Support bar 21 Etching area 22 Etching device 23 Tie bar 24 Plating device 25 Tape attaching device 26 Inspection device 27 Depress device 28 Cutting device

Continuation of the front page (56) References JP-A-63-148667 (JP, A) JP-A-4-94157 (JP, A) JP-A-3-136267 (JP, A) JP-A-62-154766 (JP) JP-A-3-8364 (JP, A) JP-A-4-206957 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 23/50 C23C 18/31 C23F 1/00 102

Claims (2)

(57) [Claims] 1. A press for punching a part of a lead pattern in a metal sheet, and a cleaning and cleaning of the metal sheet provided downstream of the press.
A drying device, a device for baking and developing and etching a lead pattern, a device for plating a desired portion of a lead frame on which a lead pattern is formed, a tape attaching device for attaching a tape to inner leads, an inspection device, and a lead frame A depressing device that pushes down or pushes up a pad, and a cutting device that cuts a predetermined number of lead frames, and a continuous manufacturing device for lead frames manufactured by using both pressing and etching. A photoresist film sticking device that is rotatably driven in contact with a metal sheet and is provided with a braking device between the etching device and the etching device; a support roll provided opposite to the sticking device and provided with the metal sheet therebetween; An image of the guide hole drilled in the Continuous production apparatus of the lead frame, characterized in that is provided a positioning image processing apparatus for outputting a positioning carrier signal to match the reference position. 2. The continuous lead frame manufacturing apparatus according to claim 1, wherein said cutting device is provided between said etching device and said plating device.