JPH06318659A - Shape forming and treatment method of lead frame for semiconductor device - Google Patents

Abstract

PURPOSE:To comply with the diversification of the quality and the specification condition of a fine lead frame by a method wherein, while a thin-sheet stripe material is being run inside a line, a prescribed shape working and treatment is executed sequentially and continuously to the thin-sheet stripe material. CONSTITUTION:One shape working and treatment line is constituted in such a way that it is provided with a first shape working process group 10, a second shape working process group 11, a heat-treatment process group 12 continued after them, an electrolytic polishing process group 13, a multilayer plating process group 14, 3 tape pasting process group 15 and a third shape working process group and that it is connected via loop formation means 17 to 33 provided with a control device controlling the working and treatment process groups. Then, a thin-sheet stripe material in a vertical state is drawn out to the line, a required shape forming and treatment is executed sequentially on a lead frame while the thin-sheet stripe material is being run inside the line, and the lead frame provided with a prescribed quality and with prescribed specifications is former.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of processing and processing a lead frame for a semiconductor device. In detail, by forming a shape processing and processing line in which different kinds of shape processing and processing step groups are appropriately combined and connected, the transfer operation between the groups is made efficient, damage caused by the transfer is prevented, and diversified quality, The present invention relates to a shape processing and processing method of a lead frame for a semiconductor device, which provides a high quality lead frame corresponding to flexibility in use conditions.

[0002]

2. Description of the Related Art Conventionally, a method of processing and processing a lead frame for a semiconductor device, which is constructed as shown in FIG. 3, will be described with reference to FIG. 4, FIG. 5, FIG. Four
8, a thin strip material is attached upstream, and the thin strip material fed in a horizontal state is intermittently conveyed to the first shape processing device 48 by the intermittent conveying means 4
In step 2, a desired shape is formed while the tip of the inner lead is left while being intermittently supplied into the shape processing mold device 44 which is mounted on the press device 43 and integrated. And the coiled thin strip material is mounted upstream of the heat treatment apparatus 59 to
9, a bridging means provided upstream and downstream of the heat treatment device 59 while applying a required tension to the thin strip material and traveling in the heat treatment device 59 to remove the retained internal residual stress. And the coiling thin plate material formed in the above step is mounted upstream of the plating device 68, and is fed toward the plating device 68, and inside the plating device. While performing traveling, the pretreatment 62, the plating treatment 63, and the posttreatment 64 are performed, and the coiled thin plate material formed in the above step is wound into the coil shape on the winding means 67. The thin strip material, which is mounted upstream of the shape processing device and is fed horizontally toward the first shape processing device, is transferred to the press device 83 by the intermittent transfer means 82 provided in the first shape processing device 88. A batch which performs processing and processing in the order of the step of forming the tip end portion of the inner lead into a desired shape while intermittently supplying it into the shape processing mold device 84 that has been attached, and winding it into a coil by the winding means 87. A method of processing and processing the lead frame by a method is common.

[0003]

Recently, as semiconductor devices have become lighter, thinner, shorter, and smaller, higher quality and reliability have been required for lead frames for semiconductor devices. However, due to improvements in thin metal strip material, the lead has been improved. It is difficult to deal with the diversification of quality specifications required for the frame, and it is necessary to deal with the diversification of processing and treatment in the process of forming the lead frame. There is a demand for a method of manufacturing a lead frame for a semiconductor device, which is capable of performing one-step processing and treatment with flexibility so that connection and separation can be changed at any time.

Further, with the high integration of semiconductor devices, the number of leads for circuit formation increases, the lead width and the interval between leads become finer, and there is a delay during the forming and forming of thin sheet material and the forming and coining of leads. There is a problem that internal residual stress and punching burrs and protrusions cause minute deformation during formation and processing of the lead frame and reduce the quality and yield of the lead frame.Intermediate processing is required during shape processing and processing. There was a need to do so.

Further, it is difficult to form a fine shape required for a lead frame (the number of leads for forming a circuit is 160 or more) only by press punching, and it is necessary to appropriately combine different shape processing methods and processing methods. was there.

Further, in the conventional method, since winding and winding are carried out in a coil shape for each processing and processing step, minute leads of the lead frame are bent, leaned, deformed or damaged such as curling, and processed. However, there is a problem in that an oxide film is formed on the treated portion, the number of post-treatment processes is increased, and the quality and yield of lead frames are reduced.

The present invention has been made in view of the above circumstances, and when carrying out a predetermined shape processing and processing of a lead frame for a semiconductor device, the respective carrying operations between the processing and the processing steps are made efficient and carried. A semiconductor device that can prevent damage caused in the process and configure a shape processing and processing line that can easily combine different kinds of processing and processing steps, and can respond to the diversification of fine lead frame quality and specification conditions. The purpose of the present invention is to provide a lead frame shape processing and processing method.

[0008]

According to the first aspect of the present invention, there is provided a method for processing and processing a lead frame for a semiconductor device, wherein the shape stages of a progressive die device for forming the lead frame are independently pressed. And a plurality of shape processing means are appropriately combined to form a plurality of shape processing step groups, and an internal residual stress that is retained by the shape processing upstream between the groups or between the groups. Heat treatment step group including a tension applying means for removing the metal, electrolytic polishing or / and chemical polishing step group for removing punching burrs and protrusions generated in the upstream shape processing, and plating treatment for metallizing a required portion of the lead frame. At least one of the above-mentioned processing step group among the different kinds of processing step groups such as the lead fixing processing step group such as taping for preventing deformation and deviation between the step group and the lead frame Are connected by a required number of loops through a loop controlled by a controller that maintains a required loop amount, and these constitute a U-shaped continuous one-step shape processing and processing line. And, the thin strip material fed in a vertical state or a horizontal state is supplied to the processing line, and the thin strip material is moved in the line by a conveying device provided in each of the processing and processing means. At the same time, the thin strip material is subjected to required shape processing and treatment successively in order to form required leads.

According to a second aspect of the present invention, there is provided a semiconductor device lead frame shape processing and processing method, wherein the semiconductor device lead frame shape processing and processing method comprises: A part of the shape processing step group is replaced with a different shape processing step group such as photo-etching.

[0010]

In the shape processing apparatus of the lead frame for a semiconductor device according to claim 1, the shape processing stages arranged in a conventional integral type progressive die apparatus are provided as independent shape driving means. Since it is divided, it is possible to easily form a plurality of shape processing steps by appropriately combining the shape processing means.

Further, since a plurality of shape processing process groups are formed separately, a heat treatment process group, an electrolytic polishing or / and chemical polishing process group, a plating process group, a lead fixing process such as taping are formed between the groups. It is possible to easily form various shape processing and processing lines in one step by appropriately combining different processing step groups such as groups.

Further, since the one-step shape processing and processing line is constructed, the number of times of winding and feeding the thin strip material into a coil can be reduced and the processing waiting can be eliminated.

In the method of processing and processing the lead for the semiconductor device according to the second aspect, since the shape processing process group is divided, the shape processing of the fine inner lead which requires the shape and size is performed. A combination line of different shape processing can be configured by easily replacing the different shape processing process group such as photo etching.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Below, based on the drawings attached to this specification,
Examples for embodying the present invention will be described to provide an understanding of the present invention. FIG. 1 is a block diagram for explaining the outline of the shape processing of a semiconductor device lead frame and the arrangement of processing lines according to an embodiment of the present invention. FIG. 2 shows a plan view of a single lead frame formed in this example.

According to the first embodiment of the present invention, a lead frame for a semiconductor device has a first shape processing step group 10 and a second shape processing step group 11 as shown in FIG. , The heat treatment process group 12 arranged after that
An electrolytic polishing step group 13, a multi-layer plating step group 14,
Loop forming means (17, 18, 19, 20) having a tape adhesion process group 15 and a third shape processing process group 16 and provided with a control device for controlling these processing and processing process groups.
21, 22, 23, 33) connected through the shape processing,
One line of processing is constituted, and the thin strip material is fed to this line in a vertical state, and while the thin strip material travels in the line, the required shape processing and processing of the lead frame are sequentially performed to perform predetermined processing. A lead frame with quality specifications is formed. These will be described in detail below.

The first shape working process group 10 forms and maintains a winding device 24 for intermittently feeding the strip-shaped thin strip material A wound in a coil upstream of the working process group 10 and a constant loop amount. The loop forming means 17 and the intermittent conveying device 25 for feeding according to the machining speed of the machining step group 10 are arranged on both sides thereof, and the thin strip material A is fed to the machining step group 10.

The first shape processing step group 10 includes an outer lead 73 and an inner / outer frame 70 that supports the outer lead 73, as shown in FIG.
Also, the processing stage for forming the shape of the pilot hole 75 and the like is divided into shape processing means provided with an independent pressure driving means (not shown) and appropriately arranged.

In the shape processing step group 10, an outer lead 73, an inner and outer frame 70 and a pilot hole 75 for supporting the outer lead 73 are formed in the thin strip material A, and a part of the shape of a lead frame (not shown) is formed. The thin strip material B in which is formed is obtained.

The thin strip material B formed by the shape processing step group 10 forms a loop of the thin strip material B having a constant loop amount by the loop forming means 18 arranged downstream of the processing step group 10. .

Next, the second shape processing step group 11
The processing step group 11 for intermittently feeding out the thin strip material B formed by the loop forming means 18 upstream of the processing step group 11
The thin sheet strip B is sent to the working step group 11 by disposing the intermittent feeding devices 25 for feeding at the working speed of No. 2 on both sides thereof.

In the second shape processing step group 11, as shown in FIG. 2, an element mounting portion 71 in the center, a suspension lead 74 for supporting the element mounting portion 71, a processing stage for forming the inner lead 72 and the like are not shown and are independent. The pressure driving means is divided and appropriately arranged.

In the shape processing step group 11, the element mounting portion 71 and the inner lead 72 having a shape in which a connecting piece for connecting the leading end portions is left are additionally processed on the thin strip material B and not shown. A thin strip material C having an intermediate shape of the lead frame is obtained.

The thin strip material C formed in the shape processing step group 11 forms a loop of the thin strip material material C having a constant loop amount by the loop forming means 19 arranged downstream of the processing step group 11. .

Next, the heat treatment step group 12 conveys the thin strip material C formed by the loop forming means 19 upstream of the heat treatment step group 12 at a processing speed of the heat treatment step group 12 which is fed out. Are provided on both sides thereof, and the conveying device 26 is provided with a bridal roll (not shown) for applying a required tension to the thin strip material C, and the thin strip material having a predetermined tension applied to the heat treatment step group 12. I am sending C.

The heat treatment step group 12 comprises an oxidation preventive atmosphere furnace comprising means for residual heat 27, heating 28, and slow cooling 29.

In the heat treatment step group 12, the thin strip material C is supplied to the oxidation preventive atmosphere furnace, and is subjected to residual heat 27, heating 28, and gradual cooling 29 to perform first and second shape processing. A thin strip material D from which the generated internal residual stress is removed is obtained.

The thin strip material D processed in the heat treatment step group 12 forms a loop of the thin strip material D in which a constant loop amount is maintained by the loop forming means 20 arranged downstream of the heat treatment step group 12. To do.

Next, the electrolytic polishing step group 13 sends the thin strip material D formed by the loop forming means 20 upstream of the electrolytic polishing step group 13 according to the processing speed of the electrolytic polishing step group 13 which is fed out. The transport devices 25 are arranged on both sides of the
The thin strip material D is sent to the electrolytic polishing step group 13.

The electropolishing process group 13 comprises an electrolytic solution tank (not shown) and a power supply device for applying an electrolytic current to the thin strip material D.

In the electropolishing step group 13, the thin strip material D is supplied to the electropolishing step group 13 and subjected to anodic electropolishing treatment using CrO ₃ system as an electropolishing solution. A thin strip material E from which punching burrs and protrusions such as protrusions generated in the second shape processing are removed is obtained.

The thin strip material E processed in the electropolishing process group 13 is maintained in a constant loop amount by the loop forming means 21 arranged downstream of the electrolytic polishing means group 13. Form a loop.

Next, the multi-layer plating step group 14 feeds the thin strip material E formed by the loop forming means 21 upstream of the multi-layer plating step group 14 in accordance with the processing speed of the multi-layer plating step group 14. Devices 30a, 30b, 30
c is arranged at a required position, and the transfer devices 30a, 30b,
30c applies a required tension to the thin strip material E, adds the thin strip material E to the multi-layer plating step group 14 and sends the thin strip material E.

The multi-layer plating step group 14 is a power feeding means for applying a predetermined plating current to the contact surface of the thin strip E, and the transfer devices 30a, 30b, 30c for transferring while vertically controlling the swing. A pretreatment means 31 for treating the thin strip material E with a pretreatment for plating and a base plating; a multi-layer plating treatment means 32 for treating a required portion of the thin strip material E with the undercoat with peeling and cleaning. It is configured to have a post-processing means 34 for processing.

In the multi-layer plating step group 14, pre-plating treatment and formation of an underplating layer of copper, nickel or the like is performed on a predetermined portion of the thin strip material E, and the underplated thin strip material E is formed. Multilayer plating of noble metal such as gold, silver and palladium on required parts, then peel off unnecessary parts such as copper,
Washing is performed to obtain a thin strip material F in which the thin strip material E is subjected to multi-layer plating.

The thin strip material F processed in the multi-layer plating step group 14 forms a loop of a constant loop amount by the loop forming means 22 arranged downstream of the multi-layer plating step group 14.

Next, the tape adhering process group 15 sends the thin plate material F formed by the loop forming means 22 upstream of the tape adhering process group 15 according to the processing speed of the tape adhering process group 15. Device 35 and tape supply device 3 for supplying a tape 36 to be adhered to the thin strip material F
7 and a shape processing device 40 having a forming and processing means 38 for forming a desired tape shape and a thermocompression bonding means 39,
The thin strip material F and the tape 36 are configured to adhere in a predetermined tape shape at the intersecting position.

In the tape adhering step group 15, a tape of a predetermined shape is adhered to a lead required portion of the thin strip material F at a crossing position of the supplied thin strip material F and the tape 36, and leads are attached. The adhered thin strip material G is obtained.

The loop forming means 23 arranged downstream of the tape adhering process group 15 forms a loop of the thin strip material G with a constant loop amount.

Next, the third shape processing group 16
Intermittent conveying devices 25 for feeding the thin strip material G formed by the loop forming means 22 on the upstream side of the processing group 16 at intermittent intervals are arranged on both sides of the conveying means 25. The thin strip material G is sent to the processing means group 16.

The third shape processing step group 16 includes shape processing such as removal of connecting pieces (not shown) connecting the tips of the inner leads 72, straightening of the tips, punching such as depressing of the element mounting portion, coining and bending. Is divided into shape processing means provided with independent driving means, and is appropriately arranged.

In the third shape processing step group 16, the leading end of the thin strip material G and the element mounting portion are subjected to processing such as coining and bending to remove the connecting piece from the required lead frame. A thin strip material H that has been subjected to shape processing is obtained.

The thin strip material H formed in the third shape processing step group 16 is sequentially wound by the winding device 39 arranged downstream of the processing step group 16, or the third shape processing step 16 is performed. An intermittent cutting means is provided in the processing group 16 to form a unit frame in which a required number of individual lead frames are connected to obtain the lead frame.

Furthermore, the method of processing and processing the lead frame for a semiconductor device according to the second embodiment of the present invention is shown in FIG.
As shown in, a first shape processing step group 301, an electrolytic polishing step group 302, a second shape processing step group 303 that is an etching process, a multilayer plating means group 304, a tape adhesion step group 305, A loop forming means (307, 308, 309, 3) having a third shape processing step group 306 and including a control device for controlling the processing and processing step groups.
10, 311, 312, 313, 314), and a line for forming and processing is formed in the same manner as in the first embodiment, and a thin strip material is vertically fed to the line, While the thin strip material is running in the line, the lead frame is shaped in the first shaping step group 301 to remove the punching burrs and protrusions generated by the above-mentioned processing. After performing shape processing to form a fine inner lead portion by an etching method using a film, the steps before the multilayer plating processing step group 304, the lead fixing processing step group 305, and the third shape processing step group 306 are sequentially performed. A lead frame in which fine lead portions have predetermined quality specifications is obtained.

[0044]

As described above, the method of processing and processing the lead frame for a semiconductor device according to claim 1 is
Since the shape processing step group is easily configured by the shape processing means having the independent driving means, various shape processing step groups can be easily configured as compared with the conventional integrated type progressive die. It is possible to easily and swiftly respond to the demand for diversified shapes.

Further, one group of the above-mentioned groups or groups can be easily connected by a heterogeneous group of treatment steps such as a heat treatment step group, an electrolytic polishing and / or chemical polishing step group, a plating treatment step group and a lead fixing treatment step group. Since it is possible to easily configure various shape processing and processing lines, it is possible to easily provide lead frames of a large number of small quantities and similar kinds.

Furthermore, the thin plate material is wound into a coil, the number of times of feeding is reduced, and the waiting time for processing is reduced. Therefore, damage such as deformation of the lead frame due to winding and feeding is reduced, and rust and oxide film due to waiting for processing are reduced. Is reduced, and the yield of the subsequent process is improved to improve the quality of the lead frame.

In the shape processing and processing of the lead frame for the semi-conductive device according to the second aspect, since the shape processing process group is divided, the shape processing of the fine inner lead which requires the shape and size is performed. A combination line of different shape processing and processing can be configured by easily replacing the photo etching different shape processing process group.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating an outline of a shape processing of a semiconductor device lead frame and an arrangement of processing lines according to an embodiment of the present invention.

FIG. 2 is a plan view of a single lead frame formed in the first embodiment.

FIG. 3 is a block diagram illustrating an outline of the shape processing of the semiconductor device lead frame and the arrangement of the processing lines in the second embodiment of the present invention.

FIG. 4 is a schematic explanatory view showing a conventional shape processing apparatus.

FIG. 5 is a schematic explanatory view showing a conventional heat treatment apparatus.

FIG. 6 is a schematic explanatory view showing a conventional plating apparatus.

FIG. 7 is a schematic explanatory view showing a conventional plating apparatus.

[Explanation of symbols]

 10 First Shape Processing Step Group 11 Second Shape Processing Step Group 12 Heat Treatment Step Group 13 Electropolishing Step Group 14 Multilayer Plating Step Group 15 Lead Fixing Step Group 16 Third Shape Processing Step Group 17-23 Loop Formation Means 24 Unwinding device 25 Intermittent conveying device 26 Conveying device 27 Preheating part 28 Heating part 29 Slow cooling part 30a to 30c Conveying device 31 Pretreatment means 32 Multilayer plating means 33 Loop forming means 34 Post-treatment means 35 Conveying device 36 Tape 37 Tape supply device 38 Forming processing means 39 Thermocompression bonding means 40 Shape processing device AK Thin sheet material 301 First shape processing step group 302 Electropolishing step group 303 Second shape processing step group 304 Multi-layer plating step group 305 Tape Adhesive process group 306 Third shape processing process group 17-23 Loop forming process 307- 13 loop forming means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Muneya Shibata 2-10-1 Komine, Hachimansai-ku, Kitakyushu City, Fukuoka Mitsui High-Tech Co., Ltd.

Claims (2)

[Claims] 1. A shape processing stage of a progressive die apparatus for forming a lead frame is divided into shape processing means each provided with an independent pressure driving means, and the shape processing means are appropriately combined to form a plurality of shape processing means. A heat treatment step group that constitutes a step group and is provided between the groups or between the groups with a tension applying means for removing an internal residual stress that has remained in the upstream shape processing, and a punching burr or protrusion generated in the upstream shape processing. Heterogeneous treatments such as electrolytic polishing and / or chemical polishing treatment step group for removing the lead and plating treatment step group for metal-coating a required portion of the lead frame and lead fixing treatment step group such as taping for preventing deformation or deviation between the leads Among the process groups, at least one of the processing process groups is connected in a required number through a loop controlled by a controller that maintains a required loop amount, and these are U-shaped. Form a continuous one-step shape processing and processing line, and supply the thin strip material fed in the vertical state or the horizontal state to the shape processing and treatment line, And, while the thin strip material is traveling in the line by a transport device provided for each of the processing step groups, the thin strip material is successively subjected to required shape processing and treatment to form a required lead frame. A method for processing and processing a lead frame for a semiconductor device, comprising: 2. The lead for a semiconductor device according to claim 1, wherein the shape processing and processing line is configured by replacing a part of the shape processing step group with a photoetching shape processing step group. Frame shape processing and processing method.