JPH11233705A - Electrodeposition treatment equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of pin holes on electrodeposition resist formed by electrodeposition, by forming an electrodeposition liquid supplying part supplying electrodeposition liquid from the lower side of an electrodeposition tank to the upperside, and an overflow receiver for collecting or circularly using overflow liquid on the upper surface side of electrodeposition liquid. SOLUTION: An electrodeposition liquid supplying part 150 sends electrodeposition liquid in an electrodeposition liquid pool 151 to the lower side part of an electrodeposition liquid tank 120 via a filter 153 by using a pump 152, and supplies electrodeposition liquid upward in a vertical direction, via a rectifying plate 137. An overflow receiver 125 is used for collecting or circularly using overflow liquid and installed on the upper surface side of the electrodeposition liquid 127. An electrode 130 is arranged at a position between the height of a turn roll 143 arranged in the electrodeposition liquid 127 and the height of the electrodeposition liquid 127, and a diaphragm 135 for preventing bubbles from passing is arranged between the electrode 130 and a member 110 to be electrodeposited. As a result, bubbles can be prevented from adhering to the member 110 to be electrodeposited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electro-deposited material made of a strip-shaped metal sheet or a thin sheet of resin or the like, which is continuously or intermittently conveyed while the strip-shaped state is maintained. The present invention relates to an electrodeposition processing apparatus for forming an electrodeposition resist by electrodeposition. Particularly, a lead in which the material to be electrodeposited is obtained by perforating a band-shaped metal plate material and processing one or more product parts via the connecting portion in the band-shaped metal plate material. The present invention relates to a photosensitive electrodeposition resist electrodeposition processing apparatus for producing a plating mask for a frame externally processed product.

[0002]

2. Description of the Related Art Conventionally, a (single-layer) lead frame used as an assembly member of a resin-encapsulated semiconductor device is formed by a pressing method or an etching method. Generally, as shown in FIG. A die pad 711 for mounting a semiconductor element, and an inner lead 712 for connecting to a semiconductor element provided around the die pad 711
And an outer lead 713 for connecting the inner lead 712 to an external circuit, a dam bar 714 serving as a dam for resin sealing, a frame (frame) portion 715 supporting the entire lead frame 710, and the like. Have.
Then, a lead frame (single-layer lead frame) 710
Is usually made of metal having excellent conductivity such as Kovar, 42 alloy (42% nickel-iron alloy), and copper-based alloy,
As shown in FIG. 7B, a semiconductor element 720 is mounted on a die pad 711, and terminals (pads) of the semiconductor element 720 are provided.
The semiconductor device 700 has been manufactured by connecting the wire 721 to the tip of the inner lead 712 with a wire 730 such as gold and then sealing it with a resin 740. As described above, since the terminal (pad) 721 of the semiconductor element 720 and the tip of the inner lead 712 are connected by the wire 730 such as gold, silver plating having excellent conductivity and strong bonding force with the wire is applied. In general, partial silver plating is applied to the tip of the inner lead on the semiconductor element mounting side.

Conventionally, this partial silver plating process uses a plating apparatus 500 as shown in FIG. 5 and a masking jig 520 except for a region to be plated of a continuous lead frame 510 having several lead frames. A jig plating method of a sparger type in which plating is performed while applying a plating solution 580 ejected from a nozzle 540 to an area to be plated is mainly performed. With this jig plating method, a jig is required for each type of lead frame, and it takes a long time to manufacture the jig, and wear and fatigue occur as the jig is used. Problems in terms of cost and cost. In consideration of plating quality, positioning is performed by positioning pins and plating is performed after pinching and holding a single lead frame with upper and lower jigs. Therefore, plating quality such as plating position accuracy and plating thickness uniformity is improved. It is susceptible to the accuracy of the manufactured jig and the accuracy of the mounting. In addition, there is a problem that plating easily deposits on the side and back surfaces of the lead frame, which does not originally require plating, and requires a high level of empirical technology for adjustment. Furthermore,
Due to the increase in the number of input / output terminals of semiconductor devices due to advances in semiconductor processes and the narrowing of the inner leads due to the miniaturization of package sizes, the dimensional accuracy of plated parts has become even more severe, and dimensional accuracy is also being addressed. It's getting harder.

For this reason, a jig is not required, and it is possible to cope with an increase in the number of terminals of a semiconductor element and a reduction in an inner lead portion. Using a photosensitive electrodeposition resist having resistance to a plating solution as shown in the drawing, only a predetermined area of a lead frame of one frame (also referred to as a single unit) having a set of several lead frames is used as a plating solution. A silver plating method of a lead frame, which is masked and plated in an exposed state, has also been adopted. A partial silver plating method using the electrodeposition resist will be briefly described with reference to FIG. FIG. 4 shows a cross section of a part (characteristic portion) of a lead frame for explaining the partial silver plating method using the electrodeposition resist. First, the entire lead frame 410 is electrolytically degreased, pickled, and chemically polished (FIG. 4A), and then the entire surface of the lead frame 410 is subjected to copper strike plating 430 as base plating (FIG. 4).
(B)) Then, an electrodeposition resist 420 is formed on the entire surface. (FIG. 4C) Next, using a predetermined pattern plate 450, a predetermined portion (a tip portion of the die pad 411 and the inner lead 412).
Is exposed to ultraviolet light (exposure light) 460 to cure only the exposed portions (FIG. 4D). Then, development processing is performed to remove the electrodeposited resist 420 in the unexposed portions.
A is exposed (FIG. 4E). Next, after the exposed plating portion 440A is washed, the entire lead frame is immersed in a silver plating solution, plated with a predetermined current density and time while stirring, and a desired film is deposited on the plating portion 440A. A thick silver plating (film) 440 is obtained. (FIG. 4 (f)) Thereafter, the electrodeposited resist 420 is peeled off by a peeling solution to obtain a lead frame 410A having a silver plating (film) 440 only in a predetermined region. (FIG. 4 (g))

In order to form an electrodeposited resist in the silver plating method of a lead frame using the electrodeposited resist shown in FIG. 4, a strip-shaped metal sheet material is punched and processed to form a product. In recent years, a method of performing electrodeposition in a belt-like state holding ()) has been adopted from the viewpoint of processability and workability. In this method, as shown in FIG. 3, electrodeposition is performed in an electrodeposition bath 320 while the surface of the material to be electrodeposited 310 is kept in a belt shape while being conveyed in a substantially horizontal direction. However, in this method, the material to be electrodeposited 31
0 is conveyed in the horizontal direction, bubbles generated on the surface of the material 310 to be electrodeposited during electrodeposition tend to stay on the lower surface, and pits are formed on the electrodeposition resist formed by electrodeposition due to the bubbles. (Pinholes) often occur, which has been a problem. In addition, when the material to be electrodeposited 310 enters and exits the electrodeposition bath 320, a liquid leaks. Therefore, one end of the leaked electrodeposition liquid 313 is collected in an electrodeposition liquid storage 325, and the collected electrodeposition liquid 313 is filtered by a pump 340. Discharge piping 34 via 345
The electrodeposition liquid circulation system is circulated again from step 9 and returned to the electrodeposition tank 320. However, since the amount of liquid to be circulated is large, bubbles cannot be completely removed during the circulation, causing bubbles in the circulation path. The occurrence of pits (pinholes) in the electrodeposition resist is also observed, which is a problem. In the case of the apparatus shown in FIG. 3, bubbles generated when the material to be electrodeposited may be directly adhered to the surface of the material to be electrodeposited.

In the case of the method shown in FIG. 3, while being held by a strip-shaped (hoop-shaped) thin metal sheet material, a noble metal plating such as silver plating is continuously applied as shown in FIG. It has also been attempted to do so. In FIG. 6, reference numeral 611 denotes a hoop-shaped processing material holding a large number of externally processed products provided with an electrodeposition resist at connecting portions, 620 denotes a precious metal plating tank, 613 a precious metal plating solution, and 660 denotes a transport fixing. 670 is an electrode. Incidentally, FIG.
It is sectional drawing in B1-B2 of (a).

[0007]

As described above, when a noble metal plating is performed on a lead frame, a photosensitive electrodeposition resist having resistance to a plating solution is used as a plating mask without using a jig. Although plating methods have been adopted, pits (pinholes) are generated in the electrodeposited electrodeposited resist, and quality measures have been demanded in terms of productivity and mass productivity. The present invention is obtained in such a situation by punching a band-shaped metal sheet material and processing the outer shape,
In addition, plating of an electrodeposited resist for plating only a predetermined area on a lead frame externally processed product in which one or a plurality of product parts are held on the strip-shaped metal sheet material via a connecting part. To make a mask,
An electrodeposition processing apparatus for use in a process of electrodepositing a photosensitive electrodeposition resist, which is intended to provide an electrodeposition processing apparatus capable of suppressing generation of pits (pinholes) in the electrodeposited electrodeposition resist. Things.

[0008]

SUMMARY OF THE INVENTION An electrodeposition processing apparatus according to the present invention is an apparatus for electroplating a belt-like metal sheet or a thin sheet of resin or the like while transporting a material to be electrodeposited thereon. An electrodeposition processing apparatus for electrodepositing a resist, and a plurality of turn rolls on the upper side of the electrodeposition liquid surface of the electrodeposition tank,
At least one turn roll is provided in the electrodeposition solution, and the plurality of turn rolls on the upper side of the electrodeposition liquid surface of the electrodeposition tank and the turn roll provided in the electrodeposition solution are used to electrodeposit the material to be electrodeposited. It is transported in the vertical direction while submerged in the liquid.The flow of the electrodeposition liquid in the electrodeposition tank is set from bottom to top, and the bubbles in the electrodeposition liquid are allowed to flow out of the electrodeposition tank. An electrodeposition liquid supply unit for supplying the electrodeposition liquid upward from the bottom of the bath, and an overflow receiver for collecting or circulating the liquid overflowing on the upper surface side of the electrodeposition liquid are provided. It is characterized by the following. In the above, a diaphragm for preventing the passage of air bubbles is provided between the electrode and the material to be electrodeposited. Further, in the above, for the electrodeposition liquid in the vicinity of the material to be electrodeposited, a flow is locally generated in a predetermined direction, and a nozzle for controlling the flow of the electrodeposition liquid is provided. Wherein the nozzle is provided in the vicinity of a place where the material to be electrodeposited in the electrodeposition liquid enters the electrodeposition liquid. Further, in the above, in the direction of movement of the electrodeposited material, at a position ahead of the turn roll provided in the electrodeposition liquid, at a position near the position where the electrodeposited material is separated from the turn roll, and at a position near the electrodeposited material. A nozzle for locally generating a flow in an arbitrary direction with respect to liquid landing is provided. Further, in the above, the material to be electrodeposited is obtained by forming a hole in a band-shaped metal plate material, and one or more product parts are held in the band-shaped metal plate material via a connecting portion. Wherein the material to be electrodeposited has a lead frame as a product part. Then, on the turn roll provided in the electrodeposition liquid, near the turn roll, and at a position close to the material to be electrodeposited conveyed in the vertical direction, the flow of the electrodeposition liquid from the lower part of the electrodeposition tank is changed. It is characterized in that a front and back flow rate adjusting part for directing a part toward the material to be electrodeposited is provided. Further, in the above, the electrode is disposed at a position between the height of a turn roll provided in the electrodeposition liquid and the height of the electrodeposition liquid surface. Further, in the above, the invention is characterized in that a distance adjusting unit capable of changing a distance between the electrodeposited material and the electrode or a distance between the electrodeposited material and the diaphragm is provided.

[0009] Here, generating a flow in the electrodeposition liquid by means of the nozzle means that a flow for changing the liquid flow is provided in a predetermined direction with respect to the liquid flow without the nozzle.

[0010]

According to the electrodeposition treatment apparatus of the present invention, the material to be electrodeposited made of a thin metal sheet or a thin sheet of resin or the like is conveyed while maintaining the belt-like state.
This is an electrodeposition processing apparatus for electrodepositing an electrodeposition resist on the surface, which makes it possible to provide an electrodeposition processing apparatus with less occurrence of pits (pinholes) in the electrodeposition resist and good workability. In particular, a lead frame in which the material to be electrodeposited is obtained by perforating a strip-shaped metal sheet material, and one or more product parts are held in the strip-shaped metal sheet material via a connecting portion. In the case of an externally processed product, the electrodeposition processing apparatus of the present invention is effective, and this apparatus makes it possible to produce a plating mask composed of an electrodeposition resist for plating only a predetermined area in quality. In addition, high efficiency can be achieved in terms of workability, and mass production can be expected. Specifically, a plurality of turn rolls above the electrodeposition liquid surface of the electrodeposition tank,
At least one turn roll is provided in the electrodeposition solution, and the plurality of turn rolls on the upper side of the electrodeposition liquid surface of the electrodeposition tank and the turn roll provided in the electrodeposition solution are used to electrodeposit the material to be electrodeposited. It is transported in the vertical direction while submerged in the liquid.The flow of the electrodeposition liquid in the electrodeposition tank is set from bottom to top, and the bubbles in the electrodeposition liquid are allowed to flow out of the electrodeposition tank. The electrodeposition liquid supply unit that supplies the electrodeposition liquid upward from the bottom of the bath and the overflow receiver for collecting or circulating the overflowed liquid on the top side of the electrodeposition liquid are provided. Has achieved this. That is, while the material to be electrodeposited is conveyed in the vertical direction, the flow of the electrodeposition liquid in the electrodeposition bath is made from the bottom to the top so as to follow the surface of the material to be electrodeposited (the traveling direction). By controlling with the liquid supply unit and overflow receiver, basically, bubbles generated on the surface of the electrodeposited material during electrodeposition or bubbles generated by other causes stay on the surface of the electrodeposited material. It is difficult. As a result, bubbles are prevented from causing pits (pinholes) in the electrodeposited resist film formed by electrodeposition. Furthermore, for the electrodeposition liquid in the vicinity of the material to be electrodeposited, a flow is locally generated in a predetermined direction, and a nozzle for controlling the flow of the electrodeposition liquid is provided. I have. In particular, by providing a nozzle near the position where the material to be electrodeposited in the electrodeposition liquid enters the electrodeposition liquid, the electrodeposition material of bubbles generated when the electrodeposited material enters the electrodeposition liquid. Thus, the formation of pits (pinholes) in the formed electrodeposition resist due to the bubbles is prevented. Also, the traveling direction of the material to be electrodeposited,
At a position ahead of the turn roll provided in the electrodeposition liquid, near the position where the material to be electrodeposited is separated from the turn roll, the electrodeposition liquid near the electrodeposition material flows locally in an arbitrary direction. By providing a nozzle for generating the electrodeposition, it is possible to prevent stagnation at this position where the electrodeposition liquid is likely to stagnate, prevent generation of excessive air bubbles from the material to be electrodeposited, and reduce the vicinity of the surface of the electrodeposited material. The retention of bubbles can be prevented. In particular, there are few through holes,
Alternatively, it is effective for electrodeposition of an electrodeposited material having no through-hole at all. In addition, by providing a diaphragm for preventing the passage of bubbles between the electrode and the material to be electrodeposited, it is possible to prevent bubbles generated on the electrode side during electrodeposition from adhering to the material to be electrodeposited and to cause the bubbles to be generated. The formation of pits (pinholes) in the formed electrodeposition resist is prevented.

Unlike the horizontal transfer as shown in FIG. 3, since the material to be electrodeposited enters the electrodeposition tank from above the surface of the electrodeposition liquid, there is no leakage of the electrodeposition liquid accompanying the entry. In the approach operation, the generation of bubbles is small, and the generation of pits (pinholes) in the formed electrodeposition resist due to the bubbles is prevented. Further, since the electrodeposition is performed while the material to be electrodeposited is transported in the vertical direction, the area occupied by the electrodeposition tank is small, and the entire electrodeposition processing apparatus can be made compact.

Further, when the electrode is disposed at a position between the height of the turn roll provided in the electrodeposition liquid and the height of the electrodeposition liquid surface, the electrode is wound at a position where the material is separated from the turn roll or around the turn roll. The amount of bubbles generated from the material at the attached position is small.

[0013] The material to be electrodeposited is obtained by perforating a band-shaped metal plate material and externally processing, and one or a plurality of product parts are held in the band-shaped metal plate material via a connecting portion. In the case of an externally processed product, for example, when the material to be electrodeposited is a framed externally processed product having a lead frame as a product part, on a turn roll provided in the electrodeposition liquid, near the turn roll, And, by providing a front and back flow rate adjustment unit for directing a part of the flow of the electrodeposition liquid from the lower part of the electrodeposition tank to the electrodeposited material side, at a position near the electrodeposited material transported in the vertical direction,
The thickness of the front and back electrodeposition films can be adjusted.

Further, by providing a distance adjusting unit which can change the distance between the electrodeposited material and the electrode or the distance between the electrodeposited material and the diaphragm, various electrodeposition conditions can be adopted. The flow rate of the electrodeposition liquid can be controlled by controlling the flow rate from the electrodeposition liquid supply unit. By making this flow rate control variable, various electrodeposition conditions can be adopted.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an electrodeposition apparatus according to the present invention will be described with reference to the drawings. FIG. 1A is a schematic view showing an example of an embodiment of an electrodeposition processing apparatus according to the present invention.
FIG. 1B is an enlarged view of A1 in FIG.
(C) is an enlarged view of A2 in FIG. 1 (a), and FIG. 2 is a diagram showing a state of an electrodeposited material that has been drilled and externally processed using a product portion as a lead frame. In addition, in the electrodeposition tank in FIG.
The arrow of the electrodeposition liquid supply unit indicates the direction of the flow of the electrodeposition liquid. 1, reference numeral 100 denotes an electrodeposition processing apparatus, 110 denotes an electrodeposited material, 115 denotes an opening, 120 denotes an electrodeposition tank, 125 denotes an overflow receiver (overflow liquid discharge unit), 127 denotes an electrodeposition liquid, and 130 denotes an electrode. Reference numeral 135 denotes a partition, 137 denotes a rectifying plate, 141 to 145 turn rolls, 150 denotes an electrodeposition liquid supply unit, 151 denotes an electrodeposition liquid storage, 152 denotes a pump, 153 denotes a filter, 154 denotes a pipe, 160 denotes a nozzle, and 170 denotes a nozzle. A front and back liquid flow rate adjustment plate (front and back liquid flow rate adjustment unit), 180 is a distance adjustment unit, 181 is a motor, 182 is a belt, and 183 is a drive support unit. The electrodeposition processing apparatus 110 shown in FIG. 1 is composed of a strip-shaped metal sheet, in which a product portion is a lead frame, and a large number of product portions are punched and externally processed in a state where the product portion is held by a strip-shaped processed material at a connecting portion. This is an electrodeposition processing apparatus for electrodepositing a photosensitive electrodeposition resist on a surface of the material to be electrodeposited 110 while continuously or intermittently transporting the material to be electrodeposited in a belt-like state. Then, two turn rolls (141, 14) are provided on the upper side of the electrodeposition liquid 127 of the electrodeposition tank 110.
2), one turn roll 143 is provided in the electrodeposition liquid 127, a plurality of turn rolls 141 and 142 are provided above the electrodeposition liquid surface of the electrodeposition tank 110, and a turn provided in the electrodeposition liquid 127. The material to be electrodeposited 110 is rolled by the
In the state where the electrodeposition liquid 127 is submerged in the vertical direction, the flow of the electrodeposition liquid 127 in the electrodeposition tank 120 is changed from bottom to top, and bubbles in the electrodeposition liquid 127 flow out of the electrodeposition tank 120. For this purpose, an electrodeposition liquid supply unit 150 for supplying the electrodeposition liquid 127 upward from the lower side of the electrodeposition tank 120 and an overflow for collecting or circulating the liquid overflowing on the upper surface side of the electrodeposition liquid 127 A receiver 125 is provided.

The electrodeposition liquid supply unit 150 includes an electrodeposition liquid storage 151.
The electrodeposition liquid inside is sent to the lower part of the electrodeposition tank 120 through the filter 153 by the pump 152, and the current plate 137 is formed.
Through which the electrodeposition liquid is supplied vertically from the bottom to the top. The filter 153 removes bubbles in the electrodeposition liquid. The current plate 137 controls the flow of the electrodeposition liquid uniformly in the vertical direction, from bottom to top, by passing the electrodeposition liquid through a hole formed in the vertical direction. To the electrodeposition liquid storage 151,
A new predetermined electrodeposition liquid or an electrodeposition liquid from an overflow receiver 125 described later is supplied. The flow of the electrodeposition liquid is created by the electrodeposition liquid supply unit 150 and the overflow receiver 125 from the bottom in the vertical direction.

The overflow receiver 125 is for collecting or circulating the overflowed liquid, and is provided on the upper surface side of the electrodeposition liquid 127. Although not explicitly shown in FIG. 1A, a slit hole is provided so that when the liquid level of the electrodeposition tank 120 reaches a predetermined height, the electrodeposition liquid spills on the overflow receiver 125 side. Nor is it limited to this.

Further, the electrode 130 is disposed at a position between the height of the turn roll 143 provided in the electrodeposition liquid 127 and the height of the surface of the electrodeposition liquid 127, so that the electrode 130 and the electrodeposition material 11
0 is provided with a diaphragm 135 for preventing the passage of air bubbles.
Thereby, it is possible to prevent bubbles generated in the electrode portion during electrodeposition from adhering to the material 110 to be electrodeposited.

Further, the vicinity of the electrodeposition material 110 entering the electrodeposition liquid 127 (position A1 in FIG. 1A) and the electrodeposition material 1
The nozzle 160 that generates the flow of the electrodeposition liquid 127 near the position where the material to be electrodeposited 110 is separated from the turn roll 143 at a position ahead of the turn roll 143 provided in the electrodeposition liquid 127 in the traveling direction of the It is arranged. In the apparatus 100 shown in FIG.
7, the nozzle 160 generates a flow of the electrodeposition liquid 127 in a direction obliquely applied to the surface of the material 110 to be electrodeposited.
In the vicinity of the position where the electrodeposited material 110 is separated from the turn roll 143, a nozzle 160 for generating a flow of the electrodeposition liquid in a direction parallel to the electrodeposited material 110 in the direction opposite to the traveling direction is provided. They may be provided as needed. Nozzle 160
As shown in FIG. 1 (b), an opening (slit shape or the like) is formed in a tubular one, and an electrodeposition liquid is blown out from the opening to generate a flow in the electrodeposition liquid 127 of the electrodeposition tank 120. It is. Although not shown, the electrodeposition processing apparatus 100 shown in FIG.
Of the electrodeposition liquid 127 of the electrodeposition tank 120
, And pressure is applied by a pump to blow out the electrodeposition liquid from the opening, but the present invention is not limited to this.

The electrodeposition apparatus 100 shown in FIG.
On the turn roll 143 provided in the electrodeposition liquid 127,
A position near the turn roll and near the electrodeposited material 110 conveyed in the vertical direction (position A2 in FIG. 1A).
In addition, a front and back liquid flow rate adjusting plate (front and back flow rate adjusting unit) 170 for directing a part of the flow of the electrodeposition liquid 127 from the lower part of the electrodeposition tank 120 toward the material to be electrodeposited 110 is provided. As shown in FIG. 1C, the front and back liquid flow rate adjusting plate (front and back flow rate adjusting unit) 170 partially obstructs the flow of the electrodeposition liquid 127 from under the electrodeposition tank 120, and causes the flow of the electrodeposited material. The remainder is sent in the direction of passing through the opening 115 of 110, and the rest passes upward through the holes of the front and back liquid flow rate adjustment plate 170 and goes upward in the vertical direction. Thereby, the flow amount of the electrodeposition liquid along the front and back surfaces of the electrodeposited material 110 can be adjusted. Note that the shape and the like of the front and back liquid flow rate adjustment plate 170 are not limited to this, and for example, a mesh shape may be used.

In addition, the electrodeposition processing apparatus 100
10 and electrode 130, or electrodeposited material 110 and diaphragm 1
The distance adjustment unit 180 that can change the distance up to 35 is provided. In the electrodeposition processing apparatus 100 shown in FIG. 1A, the distance adjustment unit 180 includes a motor 181 and a belt 18.
2, the driving support portion 183 and the like, the electrode 130, the partition wall 1
The horizontal position of 35 can be changed independently by driving the drive support 183 by rotating the motor 181, but the structure is not limited to this. This makes it possible to cope with various electrodeposition conditions.

The electrodeposition liquid is, for example, an acrylic unsaturated compound having a carboxyl group, which is dissolved in an acrylic monomer or styrene and neutralized with an organic amine, and a small amount of a photosensitizer is added. And the like. However, the electrodeposition liquid is not limited to the acrylic type, and may be, for example, a polyolefin-based or polybutadiene-based electrodeposition solution. Also,
Examples of the photosensitizer include benzoin ether.
The electrodeposition resist film may be either an anion deposition type or a cation deposition type. The photosensitive electrodeposition resist is not particularly limited to a positive type or a negative type. The electrodeposition resist is deposited on the cathode in the case of the cation type, and is deposited on the anode in the case of the anion type. Therefore, the polarity on the side of the object to be electrodeposited (lead frame outer processed product) is determined according to the type. In addition, as the lead frame material, 42 alloy (42% nickel-iron alloy), Kovar, various copper alloys can be applied, and expensive precious metal plating such as silver plating, palladium plating, and palladium alloy plating can be efficiently used. It can be attached only to the desired part.

When the material to be electrodeposited 110 is a lead frame as a product portion, for example, as shown in FIG. As shown in FIG. 7A, a single lead frame 210 shown in FIG. 2B (also referred to as a single unit) in which a single lead frame 210 is held and connected by a plurality of frames or connecting portions. 210A is replaced with a strip-shaped processing material 205.
A plurality of holes are drilled and externally processed while being held by the connecting portion 220.

[0024]

As described above, according to the present invention, an electrodeposition resist is electrodeposited on a surface of a strip-shaped metal sheet or a thin sheet of resin or the like while conveying the material to be electrodeposited. An electrodeposition processing apparatus for forming an electrodeposition resist can be provided which has less pits (pinholes) in an electrodeposition resist and has good workability. In particular, the material to be electrodeposited is obtained by punching a strip-shaped sheet metal material and processing the outer shape, and the product portion is connected to the strip-shaped sheet metal material via a connecting portion.
In the case of a lead frame externally processed product in which one or a plurality of pieces are held, the electrodeposition processing apparatus of the present invention is effective, and this apparatus is used to form a plating comprising an electrodeposition resist for plating only a predetermined area thereof. Since masks can be manufactured in terms of quality, high efficiency can be achieved in terms of workability, and mass production can be expected. In plating of a lead frame using an electrodeposition resist, there is no need to worry about plating leakage as in the jig plating method, and it is possible to plate an expensive noble metal such as silver only in a necessary area. In addition, since it is possible to cope with the miniaturization of the lead frame, that is, the narrow pitch of the inner leads, the electrodeposition processing apparatus of the present invention can cope with mass production and miniaturization of the lead frame. Further, in the present invention, the area occupied by the electrodeposition tank can be made smaller than that of the system for horizontally transporting the inside of the electrodeposition tank shown in FIG. 3, and the entire processing apparatus can be made compact.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of an embodiment of an electrodeposition processing apparatus of the present invention.

FIG. 2 is a diagram showing a state of an electrodeposited material which has been drilled and externally processed using a product portion as a lead frame.

FIG. 3 is a diagram of a conventional electrodeposition processing apparatus for coating an electrodeposition resist.

FIG. 4 is a process diagram for explaining a plating process using a conventional electrodeposition resist film.

FIG. 5 is a schematic diagram of a masking type partial plating apparatus using a jig.

FIG. 6 is a schematic view for explaining a noble metal plating method for a strip-shaped plate whose outer shape is processed using an electrodeposition resist film as a mask.

FIG. 7 is a diagram illustrating a lead frame and a semiconductor device;

[Explanation of symbols]

REFERENCE SIGNS LIST 100 electrodeposition processing apparatus 110 electrodeposited material 115 opening 120 electrodeposition tank 125 overflow receiver (overflow liquid discharge unit) 127 electrodeposition liquid 130 electrode 135 partition wall 137 rectifying plate 141 to 145 turn roll 150 electrodeposition liquid supply unit 151 Electrodeposition liquid storage 152 Pump 153 Filter 154 Piping 160 Nozzle 170 Front and back liquid flow rate adjustment plate (Front and back liquid flow rate adjustment unit) 180 Distance adjustment unit 181 Motor 182 Belt 183 Drive support unit 200 Electrodeposited material 205 Processing material 210 One lead frame 210A One frame of lead frame (one series) 220 Connection part 310 Electrodeposition material 313 Electrodeposition liquid 313A Supplementary charging liquid 320 Electrodeposition tank 323 Overflow receiver 325 Electrodeposition liquid storage 340 Pump 345 Filter 347 Pipe 349 Discharge pipe 35 Electrodeposition liquid circulation part 410 Lead frame 410A Silver-plated lead frame 411 Die pad 412 Inner lead 412A Side (edge part) 420 Electrodeposition resist film 430 Copper strike plating 440 Silver plating (film) 440A Plating part 450 Pattern plate 460 Ultraviolet ( Exposure light) 500 Plating apparatus 510 Lead frame 520 Masking jig 530 Press jig 530A Press material 530B Elastic material 540 Nozzle 550 Constant current source 560 Anode electrode 570 Cathode electrode 611 Electrodeposited material 613 Precious metal plating solution 620 Precious metal plating tank 660 Roll for transport fixing 670 Electrode 700 Semiconductor device 710 Lead frame 711 Die pad 712 Inner lead 713 Outer lead 714 Dam bar 715 Frame (frame) part 720 Semiconductor element 721 Terminal (pad) 730 Wire 740 Resin

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Teruju Momose 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Nobuhiro Sakihama 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1 Dai Nippon Printing Co., Ltd.

Claims (10)

[Claims] 1. A belt-shaped metal sheet or a thin plate made of a resin or the like while being transported, and while being transferred,
An electrodeposition processing apparatus for electrodepositing an electrodeposition resist on the surface, comprising a plurality of turn rolls on an upper side of an electrodeposition liquid surface of an electrodeposition tank, and at least one turn roll in the electrodeposition liquid. With the plurality of turn rolls on the upper side of the electrodeposition liquid surface of the electrodeposition tank and the turn rolls provided in the electrodeposition liquid, the material to be electrodeposited is submerged in the electrodeposition liquid and transported in the vertical direction. In order to make the flow of the electrodeposition solution in the electrodeposition tank from bottom to top, and to allow bubbles in the electrodeposition solution to flow out of the electrodeposition tank, An electrodeposition processing apparatus comprising: an electrodeposition liquid supply unit for supplying a liquid; and an overflow receiver for collecting or circulating the liquid overflowing on the upper surface side of the electrodeposition liquid. 2. The electrodeposition processing apparatus according to claim 1, wherein a diaphragm for preventing air bubble passage is provided between the electrode and the material to be electrodeposited. 3. An electrode according to claim 1, further comprising a nozzle for locally generating a flow of the electrodeposition liquid in a predetermined direction with respect to the electrodeposition liquid near the material to be electrodeposited. Dressing equipment. 4. An electrodeposition processing apparatus comprising the nozzle according to claim 3, wherein the nozzle according to claim 3 is provided in the vicinity of a place where the material to be electrodeposited in the electrodeposition liquid enters the electrodeposition liquid. 5. The method according to claim 1, wherein, in a traveling direction of the material to be electrodeposited, at a position ahead of a turn roll provided in the electrodeposition liquid, near a position where the material to be electroplated is separated from the turn roll, An electrodeposition processing apparatus comprising a nozzle for locally generating a flow in an arbitrary direction with respect to an electrodeposition liquid near an electrodeposition material. 6. The material to be electrodeposited according to claim 1, wherein the material to be electrodeposited is obtained by perforating a band-shaped metal plate material to form an outer shape, and the product portion is connected to the band-shaped metal plate material via a connecting portion. An electrodeposition processing apparatus characterized by being one or more externally processed products held. 7. An electrodeposition processing apparatus according to claim 6, wherein the material to be electrodeposited uses a lead frame as a product part. 8. The method according to claim 6, wherein on the turn roll provided in the electrodeposition liquid, near the turn roll,
In addition, at a position close to the material to be conveyed in the vertical direction, a front and back flow rate adjusting unit for directing a part of the flow of the electrodeposition liquid from the lower part of the electrodeposition tank toward the material to be electrodeposited is provided. Electrodeposition equipment. 9. The electrodeposition process according to claim 1, wherein the electrode is disposed at a position between a height of a turn roll provided in the electrodeposition liquid and a level of the electrodeposition liquid surface. apparatus. 10. An electrodeposition processing apparatus according to claim 1, further comprising a distance adjusting unit capable of changing a distance between the electrodeposited material and the electrode or a distance between the electrodeposited material and the diaphragm.