JPH0645493A - Outer lead correcting apparatus - Google Patents

Abstract

PURPOSE:To improve flatness of an end of an outer lead of a surface mounting type resin-sealed IC irrespective of a warpage of a package. CONSTITUTION:A lower block 3 for positioning to hold an IC 1', a holding block 7' for pressing an IC to the lower block, and a punch 4' for vertically moving to bend oppositely to the lower block are used, positioned to be held without correcting a warpage of a package, an end of an outer lead 2 is lifted, and a flatness of an end of the lead is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external lead straightening device, and more particularly to a resin-sealed SOP (SmollOutli).
(ne Package) type semiconductor device (hereinafter referred to as IC) and QFP (Quad Flat Package)
The present invention relates to an external lead straightening device for surface mounting type ICs such as type ICs.

[0002]

2. Description of the Related Art Generally, not only SOP type ICs and QFP type ICs, resin-sealed type ICs are manufactured by molding external leads with a lead molding die, put them in a tray or magazine, and then transferred to a shipping or inspection process. Such SOP type IC and QFP type I
Recently, in the surface mount type IC such as C, the flatness of the external lead tends to be more severely required, and the flatness of 100 μm is usually required, and the flatness of the high precision IC is required to be 55 μm. There is. However, due to the high integration, the size of the package became large (in the case of a large size, the size of the resin encapsulation part was 40 mm x 40 mm), and the warpage of the package was increased to 50 μm to 150 μm. The flatness afterwards deteriorated to 70 μm to 200 μm, and the requirement was not satisfied.

Therefore, a new device for correcting the external leads and improving the flatness is required.

The conventional external lead straightening device for SOP type ICs and QFP type ICs has a lower block for positioning and holding the external lead molded ICs, and an upper block for fixing the ICs together with the lower block by sandwiching the lead shoulders of the ICs. Using a bending punch that is guided by the upper block and presses the external lead tip against the lower block, after fixing the IC lead shoulder, the external lead tip deformed up and down is pressed and corrected by the lower block and the bending punch. Had improved the flat part.

[0005]

In this conventional external lead straightening die, the remolded IC is reworked in the same manner as in the lead molding to correct the lead vertical deformation and improve the lead flatness. However, since the lead shoulder is fixed with the upper block and the lower block and the warp of the package is corrected to some extent and the lead tip is corrected up and down, if the lead shoulder is opened after the lead is corrected, the package will be warped. Accordingly, there is a problem that the tip of the lead is vertically deformed, which makes it difficult to correct the lead.
In particular, when the warpage of the package is as much as 150 μm, the lead flatness of about 200 μm before straightening was 170 to 180 μm even after straightening, which was not enough to satisfy the required 100 μm.

[0006]

According to the external lead straightening device of the present invention, the lower block for positioning the resin sealing portion, the holding block for pressing the resin sealing portion against the lower block, and the external lead tip are made of resin. A device having a bending punch that pushes upwards relative to the seal is obtained. As a result, by holding the package warp without correction by the holding block and the lower block and pushing up the outer lead tip to form the lead, the flatness of the lead tip can be improved regardless of the lead shoulder position. it can.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present technology will be described with reference to the drawings.

FIG. 1 is a schematic view of a correction portion of an external lead correction type according to an embodiment of the present technology. The IC 1 is a package in which the central portion tends to be convex downward after resin encapsulation. In the lead forming process, the shoulder portion of the external lead 2 is θ ° (2 ° to 3 °).
The lead is formed by tilting downward. IC1
The lower block 3 which holds the position of is vertically guided by the bending punch 4 and the lower die set 11, and is pushed upward by the stopper pin 9 and the spring 10 to be fixed at the upper limit. The bending punch 4 is fixed to the lower die set 11, and the upper surface of the outer lead 2 in contact is mirror-finished. The upper block 5 guides the holding block 7 that is pushed downward by the spring 8 and fixed at the lower limit, and is fixed to the upper die set 20. The spring constant of the spring 8 is set larger than that of the spring 8.

First, when the IC 1 is placed on the lower block 3 and the upper die set 20 is lowered along the side surface of the lower die set and fixed at a predetermined position, the upper block 5 is lowered on the side surface and the holding block 7 is held. Contacts the center of IC1,
Are positioned and held by the lower block 3. When the upper block 5 further descends, the spring 10 contracts, the lower block 3 descends, and the IC 1 descends. At this time, since the bending punch 4 is fixed to the lower die set 11, the outer lead 2 is pushed upward. Here, since the movement amount of the lower block 3, that is, the movement amount of the upper block 5 is adjusted so that the shoulder portion of the outer lead 2 is deformed upward by θ °, the outer lead 2 is adjusted.
Can perform lead straightening without being significantly deformed upward.

In this case, since the center of IC1 is convex downward, it is held without correcting the warp of the package, and the outer lead 2 has a flat lead tip regardless of the vertical displacement of the lead shoulder, The flatness of the lead is maintained even after the lead is straightened.

FIG. 2 is a partial cross-sectional view of a correction portion of an external lead correction device according to another embodiment of the present invention.

Unlike the embodiment, the IC 1'is a package in which the central portion tends to be convex upward after resin sealing, and four corners are provided by the holding block 7'and the spring 8'provided on the upper block 5 '. It is pressed and positioned and held by the lower block 3 '.

The bending punch 4'is rotatably (rotatably) held around a pin 16 fixed to the lower die block, and guided by a support block 14 fixed to the upper surface of the lower die set 11. The roller 13 is pressed by the spring 15 so as to contact the cam 12 provided on the lower block 3 '. The cam 12 is designed so that as the lower block 3'is lowered, the outer lead low contact point of the bending punch 4'makes an arc motion about the lead shoulder.

In one embodiment, the bending punch 4 only moves linearly up and down, so pushing the outer lead 2 upward causes the outer lead 2 to slide over the surface of the bending punch 4. Therefore, the lead plating is attached to the surface of the bending punch 4, or the lead is scratched, and the slipping of the lead is deteriorated. For example, a copper alloy lead frame or a thin lead frame (0.125 mm), If an attempt is made to correct the lead of an IC using a lead frame having a weak strength, the shoulder portion of the lead may be uncorrected and the inclined surface portion of the lead may be deformed. Therefore, in another embodiment, the bending punch 4'opens and closes according to the movement of the outer lead 2 and follows the movement of the tip of the lead, so that the outer lead 2 moves upward without sliding on the surface of the bending punch 4 '. It can be pushed up to straighten the lead shoulder only.

In one embodiment, a package that tends to be convex downward is used, and in the second embodiment, a package that tends to be convex upward is used. If the IC is the same, warping will occur in the same direction due to the thickness, etc.
It is necessary to change the position of the holding block and position and hold the package without correcting the warp of the package.

[0016]

As described above, according to the present invention, since the warp of the package is not corrected and the tip of the external lead is pushed up to make the height of the lead tip uniform, the warp of the package, that is, the shoulder of the lead. The flatness of the lead tip can be improved regardless of the upper and lower portions.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a correction portion of an external lead correction device according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of a correction portion of an external lead correction device according to another embodiment of the present invention.

[Explanation of symbols]

 1,1 'IC 2 External lead 3,3' Lower block 4,4 'Bending punch 5,5' Upper block 12 Cam 13 Roller 20 Upper die set

Claims (1)

[Claims] 1. A lower block for positioning a resin sealing portion of a semiconductor device having external leads, a holding block for pressing the resin sealing portion against the lower block, and an upper block for guiding the holding block. In an external lead straightening device having a bending punch that pushes an external lead tip, which is incorporated in a lower mold so as to be movable up and down relative to the lower block, the bending punch is moved upwards relative to the resin sealing portion. Let it work,
An external lead straightening device, characterized in that the outer lead tip is pushed upward to correct downward deformation of the external lead.