JPH0737918A - Manufacture of electronic component - Google Patents

Abstract

PURPOSE:To increase an elimination effect by increasing a flow rate of air, with a flow path of air jet out from an air jet-out port toward the surface of a die being reformed, and by blowing off and eliminating resin powder and a foreign material appearing on the surface of the die at the time of plastic molding. CONSTITUTION:When air is jet out, it flows along a cylinder-shaped narrow flow path that is constituted of a base 1, a cover 3, and the surface of a die. Air jet out from an air nozzle 2, with its flow rate being accelerated, does not allow resin dust and a foreign material, which are attaching to the surface of the die, to scatter outside the die or to stay on the surface of the die. Therefore, the resin dust and the foreign material are instantly blown off towards an air attraction duct 16 and then are attracted by the air attraction duct 16 and eventually eliminated. By this method, a producibility in the plastic molding process can be remarkably increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electronic component such as an IC manufactured by resin molding.

[0002]

2. Description of the Related Art Conventionally, semiconductor elements such as LSIs and light-emitting diodes, and electronic parts such as capacitors are manufactured by molding a main part of the electronic parts in order to maintain durability against external shock and humidity. In, a so-called resin encapsulation molding is performed in which a thermosetting synthetic resin, for example, a liquid epoxy resin is hardened by heating and sealed.

This resin encapsulation molding is as follows, taking an IC as an example. A strip-shaped lead frame on which a plurality of semiconductor elements are mounted at regular intervals, after connecting each semiconductor element and an external lead with a wire,
The mold is fixed in the lower mold cavity, and the upper mold is lowered and clamped. Then, melt resin is injected into the mold cavity to seal it into a predetermined shape, and the upper mold is lifted to open the mold, and then the resin-sealed lead frame is moved to the lower mold cavity. Take out from.

If this resin encapsulation molding is continuously carried out, resin scraps and foreign substances may adhere and remain on the cavity surface of the mold, and as a result, the resin encapsulation part of the resin-encapsulated component may be left. There are defects such as chipping and mixing of foreign matter, resulting in poor appearance, and foreign matter adhering to the elements and wires, resulting in poor quality.

In order to prevent the occurrence of such a defective appearance and defective quality, a conventional removing device as shown in FIGS. 7 and 8 is used as a removing method for removing resin scraps and foreign matters.

This conventional removing device comprises a base 21 as a main body and an air cylinder 22 connected to one side surface of the base 21. A plurality of brushes 23 and an air suction nozzle 24 are provided in parallel at the upper and lower ends of the base 21, respectively, and an air discharge nozzle 25 is provided on the upper and lower sides of one side surface of the base 21 so as to be parallel to these. Has been attached. Also, the air cylinder 2
2 is driven to expand and contract to reciprocate the base 21 in the horizontal direction. In order to obtain a stable horizontal reciprocating motion of the base 21, two slide guides 26 are arranged in parallel with the air cylinder 22 on both sides of the lower surface of the base 21.

When removing the foreign matter in the above-mentioned resin-sealing molding die by using the removing device having such a structure, first, as shown in FIG. When the upper mold 27 and the lower mold 28 are opened, the fixed air cylinder 22 is driven by the inflow of air from the compressor, and the brush 23 of the base 21 is moved so as to pass between the upper and lower molds. The removal is performed by utilizing the horizontal reciprocating motion of the base 21. That is, as shown in FIG. 9, while scraping off resin scraps 30 and foreign substances 31 adhering to the mold cavities 29 in the respective facing surfaces of the upper and lower molds with the brush 23 while reciprocating the base 21, the air is removed. Discharge nozzle 2
Floating resin scraps 3 scattered by the air blown from 5
0 and the foreign matter 31 are sucked and removed from the air suction nozzle 24.

[0008]

However, since the air discharge nozzles 25 are provided in the vertical directions with respect to the upper and lower mold surfaces, respectively, and the discharged air is blown in a direction perpendicular to the mold surfaces, Was disturbed, and a turbulent flow of air was likely to occur between the upper and lower molds, and the resin scraps and foreign matter remaining on the mold surface were scattered in multiple regions. Therefore, a part of the resin scraps and foreign matters scattered from the mold surface is not sucked into the air suction nozzle 24 at a short time, and it takes a lot of time to remove the resin scraps and foreign matters from the mold surface. Was there.

The present invention has been devised under the circumstances as described above. When manufacturing electronic components, resin scraps and foreign substances generated during resin encapsulation molding of electronic components are efficiently removed and removed. An object is to improve efficiency and productivity of a resin encapsulation molding apparatus.

[0010]

In order to solve this problem, the present invention provides a resin-sealing step of resin-sealing a predetermined portion of a lead frame on which a semiconductor element is mounted with a mold, and a resin-sealing step. A step of removing the lead frame from the mold, and air is discharged toward the surface of the mold from an air discharge port provided at a predetermined position with respect to the mold to remove resin pieces and foreign matter from the mold. A method of manufacturing an electronic component, comprising: a removing step of removing from a surface and a suction step of sucking a resin piece and foreign matter removed from the mold surface to an air suction port provided at a predetermined position with respect to the mold. A method for manufacturing an electronic component, wherein a resin piece and a foreign matter are removed from the mold surface while correcting a flow path of air discharged toward the surface of the mold in the removing step. Than it is.

[0011]

[Function] When removing resin scraps and foreign substances generated during the manufacture of electronic components, the air flow path to be discharged toward the surface of the mold from the air discharge port provided at a predetermined position with respect to the mold surface is corrected. Then, while increasing the flow velocity of the air, the resin powder and the foreign matter generated on the mold surface during the resin sealing molding are scattered and removed, and the removed resin powder and the foreign matter are sucked into the air suction port just after the removal.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

When a lead frame on which a semiconductor element is mounted is sealed with a resin using a mold and the lead frame is removed from the mold after the resin is cured, resin powder and foreign matter are left on the mold surface. Adhesion remains.

In the present invention, the removing device as shown in FIGS. 1 and 2 is used to remove and suction the resin powder and the foreign matter remaining on the mold surface as follows.

As shown in FIG. 1, this removing device has a base 1 for branching air, an air nozzle 2 attached to the base 1 for discharging air, and a base 1.
The cover 3 is fixed to both side surfaces of the base 3 and the air cylinder 4 for moving the base 1 in the front-rear direction.

In this removing apparatus, the cover 3 is made of a resin-made plate-like member, and is screwed to both side surfaces of the base 1 by unillustrated bolt screws so as to face each other over the entire surface. As shown in FIG. 2, the shape of the cover 3 has a width slightly smaller than the mold opening dimension A of the upper and lower molds, and the base 1 is movable between the upper and lower molds when the upper and lower molds are opened. And has a length substantially equal to the length dimension B of the mold.

In the present invention, the cover 3 has the above-mentioned shape, but the present invention is not limited to this, and if the width dimension is smaller than the die opening dimension A, the space between the upper and lower dies is not limited. Can be configured to be movable together with the base 1. Regarding the length dimension, if the length dimension is larger than the length dimension B of the mold, it is possible to further prevent scattering of the resin powder and foreign matter attached to the mold surface.

Further, the cover 3 may be fixed to the side surface of the base 1 by means of a bolt, a screw, or the like.

As shown in FIG. 3, the base 1 has a plurality of passages formed therein for branching air, and an outer wall portion provided with an air nozzle 2 communicating with these passages. An air pipe is connected to the above and communicates with the above passage to supply air from an air source. The air nozzle 2 is formed so that air is ejected at an acute angle with respect to the mold surface. One end of the air cylinder 4 is fixed and the other end is fixed to the holding plate 5, and the holding plate 5 fixes the base 1 via the cylindrical rod 6, so that the operation of the air cylinder 4 causes The base 1 is horizontally actuatable.

When resin encapsulation molding is performed using the above-described removing device, for example, in the case of an IC, it operates as follows.

First, the upper mold 27 and the lower mold 28, which are molding dies, are the same as those of the conventional one, and the above-mentioned removing device is arranged in the vicinity of the molding dies.

The strip-shaped lead frame 7 shown in FIG.
A plurality of semiconductor elements 10 connected to the external leads 9 via the wires 8 are arranged at regular intervals in the longitudinal direction.

Then, the lead frame 7 is transferred to a desired position on the lower mold surface by a transfer means (not shown) so that each semiconductor element 10 is placed in the mold cavity 11, and a hydraulic cylinder (not shown) is driven. To lower the upper die 27 connected to the upper die 27 and the lower die 2
8 and the lead frame 7 are fixed so as to sandwich the lead frame 7.

Next, the molten resin is poured into the mold cavity 11
After the resin encapsulant that is injected into the inside to mold the resin encapsulant is fixed to the lead frame 7, the upper die 27 is lifted by the hydraulic cylinder to open the upper die 27 and the lower die 28. .

After that, the lead frame 7 is taken out from the lower mold 28 by a conveying means (not shown). At this time, the resin burr generated at the time of the resin encapsulation molding adheres to the surface of the resin encapsulant, and while the lead frame 7 is taken out and conveyed, the resin burr is separated from the resin encapsulant and becomes a resin scrap. Mold surface 2
8a, or foreign matter floats from the outside and adheres to the upper and lower mold surfaces. In order to remove the resin burr and foreign matter from the upper and lower mold surfaces, the removing device of the present invention is operated.

Air is supplied from the air source 12 to the air pipe 13
Air flows into the air supply holes 14 through the through holes 15, and the air is discharged from the air nozzles 2 through the respective through holes 15. At the same time, the dust collector 17 is operated so that the air is sucked into the air suction duct 16. Next, the base 1 horizontally reciprocates between the upper die 27 and the lower die 28 by the operation of the air cylinder 4, and at the same time, air is blown onto the upper and lower die surfaces.

At this time, the upper and lower mold surfaces are substantially surrounded by the base 1 and the cover 3 in the height direction and the lead frame conveying direction, and air suction is performed in the portion surrounded by the hatched portion shown in FIG. The state is such that two pipes are formed in the duct 16 direction.

The blown air flows along the narrow tubular flow path formed by the base 1, the cover 3 and the mold surface. Therefore, the air blown onto the die surface flows without leaking from the narrow tubular region without being dispersed and the flow path is corrected in the direction of the air suction duct 16 while increasing the flow velocity. That is, the air discharged from the air nozzle 2 does not allow resin dust or foreign matter adhering to the mold surface to be scattered to the outside of the mold or remain adhered to the mold surface while increasing the flow velocity thereof. The air is scattered in the direction of the suction duct 16 and is sucked and removed by the air suction acting in the air suction duct 16. Then, after the resin scraps and foreign substances are removed in this manner, the above-described operation is repeated.

As described above, since the high-velocity air obtained by correcting the air flow path can be blown onto the mold surface and sucked into the air suction duct 16, the upper and lower metal molds in the resin sealing molding process can be obtained. The resin dust and foreign matter remaining on the mold surface are scattered and removed in a short time, and the air suction duct 16
By sucking and removing the resin scraps and foreign substances almost completely scattered from the mold surface to the air suction duct 16 quickly and efficiently, the time required for removing the resin scraps and foreign substances can be greatly shortened. In addition, resin chips and foreign matter remain in the mold cavity 11 for resin encapsulation, and the resin encapsulant is free from chipping and foreign matter biting, resulting in no defective appearance.

In the present invention, the width dimension of the cover 3 is slightly smaller than the die opening dimension A of the upper and lower dies, but the air blown onto the die surface is the cover 3
It is desirable that the size is substantially the same as the size A so that the gas does not leak from the gap between the upper and lower molds.

The cover 3 is made of a resin to which resin dust or foreign matter is unlikely to adhere, but a metal such as aluminum may be used as long as it is difficult to deposit resin dust or foreign matter. , But not limited to this.

Although only the upper mold is movable during the resin encapsulation molding, the present invention is not limited to this. When only the lower mold is movable or the upper mold and the lower mold are movable. It can also be applied to the case.

Further, a plurality of air nozzles 2 are provided on the upper and lower surfaces of the base 1, but the present invention is not limited to this, and one air nozzle 2 may be provided on each of the upper and lower surfaces of the base 1.

In addition, in the case of using a hoop-shaped lead frame in which the lead frame is sequentially transferred without being removed after the resin sealing, as shown in FIG. With the U-shape, it is possible to move between upper and lower molds, and the present invention can be applied.

The drive of the base 1 is not limited to the air cylinder, and the drive of the die is not limited to the hydraulic cylinder.

[0036]

As described above, according to the present invention, an electronic component is manufactured through the resin sealing molding process as described above. Therefore, the resin piece and the foreign matter are corrected while correcting the flow path of the air discharged toward the surface of the mold. When removing the resin from the mold surface, while increasing the air flow rate, most of the resin scraps and foreign matter that remain on the mold surface are efficiently sucked into the air suction port, and The time required to remove it from the mold surface can be greatly shortened, and the productivity in the resin sealing step can be greatly improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a method for removing resin scraps and foreign matter remaining on a mold surface in the production of an electronic component according to the present invention.

FIG. 2 is a side view showing a method of removing resin scraps and foreign matter remaining on the mold surface in the resin sealing molding step according to the present invention.

FIG. 3 is a plan view showing a means for removing resin scraps and foreign matter attached and remaining on the mold surface in the resin sealing molding step of the present invention.

FIG. 4 is a perspective view showing a lead frame placed on the lower mold surface in the resin sealing molding step of the present invention.

FIG. 5 is a front view showing the flow paths of air blown onto the upper and lower mold surfaces in the resin sealing molding step of the present invention.

FIG. 6 is a side view showing a method of removing resin scraps and foreign matter remaining on the mold surface when a hoop-shaped lead frame is used in the resin sealing molding step of the present invention.

FIG. 7 is a perspective view showing a means for removing resin scraps and foreign matter attached and remaining on the mold surface in a conventional resin sealing molding step.

FIG. 8 is a side view showing a means for removing resin scraps and foreign matter remaining on the die surface in the conventional resin sealing molding step.

FIG. 9 is a perspective view showing resin scraps and foreign matter remaining on the lower mold surface in the conventional resin sealing molding step.

[Explanation of symbols]

 1 Base 2 Cover 3 Air Nozzle 4 Air Cylinder 5 Holding Plate 6 Cylindrical Rod 7 Lead Frame 8 Wire 9 External Lead 10 Semiconductor Element 11 Mold Cavity 12 Air Source 13 Air Piping 14 Air Supply Hole 15 Through Hole 16 Air Suction Duct 17 dust collector

Claims (1)

[Claims] 1. A resin sealing step of resin-molding a predetermined portion of a lead frame on which a semiconductor element is mounted with a mold, a step of removing the resin-sealed lead frame from the mold, and the metal mold. A removing step of ejecting air toward the surface of the die from an air ejection port provided at a predetermined position with respect to the die to remove resin pieces and foreign matters from the die surface, and removing from the die surface. In a method of manufacturing an electronic component, which comprises a suction step of sucking resin pieces and foreign matter into an air suction port provided at a predetermined position with respect to the mold, discharging toward the surface of the mold in the removing step. A method of manufacturing an electronic component, characterized in that a resin piece and a foreign substance are removed from the mold surface while correcting the air flow path.