JP5364944B2 - Mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve mold releasability of a molding by installing an ejector pin in a mold using a lease film and to adsorb/hold a release film covering the ejector pin protruding from a mold parting surface by sticking it following the mold parting surface around the tip protrusion of the ejector pin. <P>SOLUTION: The mold 100, with the release film 180 covering the ejector pin 140 protruding from the mold parting surface in a mold opening state sucked into an air suction passage through a clearance 190, is stuck following the mold parting surface around the tip protrusion of the ejector pin 140 to be adsorbed/held. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a mold for using a release film.

  As a resin sealing method for an electronic component, a resin molding apparatus using a transfer molding method in which resin in a pot is pumped to a cavity by a plunger to seal the electronic component with resin is widely known. For example, a mold using a release film is used in a resin molding apparatus using this transfer molding method.

  In general, as disclosed in Patent Document 1, a mold mold using a release film is separated from a molded product by performing resin sealing with the release film adsorbed and held on either side of the mold surface. Improves moldability. In the mold using the release film, the molded product can be reliably released without using the ejector pin. In addition, since the mold parting surface is covered with the release film, it is possible to prevent resin stains on the mold parting surface. Thereby, the frequency of the cleaning process of the mold parting surface can be reduced, the maintenance cost can be reduced, and the apparatus operating rate can be prevented from being lowered.

JP-A-11-77734

  When using molds using release films to form multiple molded products in a single resin mold, so-called multi-cavity molding, a large number of irregularities are formed at the bottom of the mold mold cavity. There has been a problem that the film has deeply digged into the irregularities at the bottom of the cavity, making it difficult to release the molded product after resin molding.

  In general, in a mold using a release film, it is not necessary to provide an ejector pin because the release of a molded product can be performed by a release film. In particular, it is difficult to employ an ejector pin for releasing a molded product in a molded product in which a resin sealing portion is a lens, such as an LED.

  If the ejector pin is provided in the release film using mold, it is provided at a position where the wiring board other than the resin sealing portion is pressed. However, the release film is adsorbed to the mold parting surface when the mold is open, but the ejector pins are provided so as to protrude from the mold parting surface when the mold is open. Hereinafter, specific description will be given with reference to the drawings.

  10A and 11A are cross-sectional views of the main part of the upper mold, and FIGS. 10B and 11B are bottom views of the parting surface. As shown in FIGS. 10A and 10B, the release film 180 sucked and held by the upper mold cavity insert 130 is lifted by the ejector pin 140 to form the projecting portion 182 and cannot be sucked uniformly. When the mold for using the release film is clamped in this state, the ejector pin 140 is retracted from the clamping surface of the upper mold cavity insert 130 as shown in FIGS. The sagging portion of the release film 180 is caught in the cavity recess 120 and a wrinkle 184 is generated. If resin sealing is performed in a state where the wrinkles 184 are caught in the cavity recess 120, the shape of the resin sealing portion (package portion) differs from the design shape of the cavity recess 120, resulting in a product defect.

  An object of the present invention is to provide an ejector pin in a mold die using a release film to improve the mold release property of the molded product, and to provide a release film that covers the ejector pin protruding from the mold parting surface to project the tip of the ejector pin. An object of the present invention is to provide a mold that adheres closely to the parting surface of the mold and holds it by suction.

Means for solving the above problems and applied to the embodiment described below has the following configuration.
That is, a mold that performs resin molding by clamping a product to be molded while holding the release film on the mold parting surface including the cavity recess of the cavity insert, and the mold on which the release film is held by suction An ejector pin is provided in a pin hole provided on the suction surface of the parting surface so as to be opposed to the wiring board portion other than the resin sealing portion of the molded product, and the ejector pin is inserted into the pin hole. The gap portion is connected to an air suction path, and the release film covering the ejector pin protruding from the mold parting surface is sucked into the air suction path through the gap portion when the mold is in the mold open state. It is characterized by closely adhering to the mold parting surface around the protruding part of the tip of the ejector pin. To.

  In addition, a suction groove connected to the air suction path is formed along the longitudinal direction of the ejector pin on the outer periphery of the ejector pin inserted into the pin hole.

  Further, suction holes for connecting to the air suction path are respectively provided in portions facing the wiring board outer edge other than the corner of the cavity recess provided in the cavity insert and the resin sealing part of the workpiece. Features.

  Further, the tip peripheral edge portion of the ejector pin is formed in an R surface shape.

  Further, as another means, there is provided a mold for performing resin molding by clamping a product to be molded while adsorbing and holding the release film on the mold parting surface including the cavity recess of the cavity insert, wherein the release film A pin on which the ejector pin is inserted in the pin hole provided on the die parting surface held by suction and facing the wiring board portion other than the resin sealing portion of the molded product, and the ejector pin is inserted An ejector pin protruding from the mold parting surface when the mold mold is in an open state, and a suction hole provided on the mold parting surface between the hole and the cavity recess is connected to an air suction path The release film covering the surface of the die is sucked into the suction hole and follows the mold parting surface around the tip protrusion of the ejector pin. Adhesion to, characterized in that it is suction-held Te.

  If the above-mentioned mold mold is used, an ejector pin is provided in the mold mold using a release film to improve the release property of the molded product, and the release film covering the ejector pin protruding from the mold parting surface is an ejector pin. It can be adsorbed and held uniformly by closely adhering to the mold parting surface around the tip protruding portion.

  In addition, if the suction groove connected to the air suction path is engraved along the longitudinal direction on the outer periphery of the ejector pin inserted into the pin hole, the clearance between the ejector pin and the pin hole is the same as the depth of the suction groove. By expanding, the air suction force can be increased, and the mold adhesion of the release film covering the periphery of the tip protruding portion of the ejector pin can be increased.

  In addition, when the suction holes connected to the air suction path are respectively provided in the portions facing the outer edge of the wiring board other than the corner of the cavity recess provided in the cavity insert and the resin sealing portion of the workpiece, the ejector By sucking the release film through the suction holes provided in the vicinity of the pins, it is possible to further increase the mold adhesion of the release film covering the periphery of the tip protruding portion of the ejector pin.

  In addition, since the tip peripheral edge of the ejector pin is formed in an R-surface shape, even if elongation occurs in the release film that covers the periphery of the tip protrusion of the ejector pin, it can be made difficult to break.

It is sectional drawing which shows schematic structure of the mold metal mold | die using the release film in 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is sectional drawing which shows the state of each resin mold process by the mold metal mold | die concerning 1st Embodiment. It is principal part sectional drawing (A) of the ejector pin vicinity of the mold die concerning 2nd Embodiment, and the bottom view top view (B) of an upper mold | type cavity insert. It is principal part sectional drawing (A) of the ejector pin vicinity of the mold die concerning 3rd Embodiment, and the bottom view top view (B) of upper mold cavity insert. It is principal part sectional drawing (A) near the ejector pin explaining the subject of the conventional mold metal mold | die, and a lower view top view (B) of an upper mold cavity insert. It is principal part sectional drawing (A) and the bottom view top view (B) of the ejector pin vicinity explaining the subject of the conventional mold die.

(First embodiment)
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic configuration of a mold using a release film in the present embodiment.
The mold die 300 includes an upper die 100 and a lower die 200, and clamps a wiring board 420 on which a plurality of semiconductor chips 410 as workpieces are mounted, and a semiconductor device is produced by resin molding the semiconductor chip 410. It is.

  The upper mold 100 includes an upper mold cavity insert 130 in which a cavity recess 120 is formed, an upper mold chase 110 to which the upper mold cavity insert 130 is assembled, and a back plate 105 provided on the back side of the upper mold chase 110. The ejector pin 140 is provided so as to protrude from the parting surface of the upper mold cavity insert 130 through the pin hole 150.

The ejector pin 140 is always biased downward by a spring 160 elastically mounted between the upper die chase 110 and the back plate 105.
The shape of the tip protruding from the parting surface of the ejector pin 140 is formed in a so-called R surface shape (R shape or curved surface shape) in which the tip peripheral edge is rounded.
Film adsorbing holes 170 for adsorbing and holding the release film 180 are provided at the corners (four corners) of the cavity recess 120 and the upper mold cavity insert 130.

  In FIG. 1, a spring accommodating portion 154 is provided on the back side of the upper chase 110, and a spring 160 is elastically mounted on the spring accommodating portion 154. The spring accommodating portion 154 communicates with the pin hole 150 into which the ejector pin 140 is inserted. The pin hole 150 is provided on the suction surface side of the release film 180 so as to face the wiring substrate 420 portion other than the resin sealing portion of the molded product. A flange portion 142 is provided at the upper end of the ejector pin 140. The ejector pin 140 is inserted from a spring accommodating portion 154 provided on the back side of the upper die chase 110 into a pin hole 150 provided through the upper die chase 110 and the upper die cavity insert 130. The spring 160 is accommodated in the spring accommodating portion 154, and the spring 160 is compressed by being disposed on the upper chase 110 so that the back plate 105 closes the spring accommodating portion 154, and the ejector passes through the flange portion 142. The pin 140 is urged so that the tip of the ejector pin 140 protrudes from the parting surface of the upper mold cavity insert 130.

  Further, the hole diameter of the pin hole 150 is formed to be slightly larger (for example, about 0.01 to 0.03 mm) than the outer dimension of the ejector pin 140. That is, a gap portion 190 is formed between the ejector pin 140 and the pin hole 150. This gap communicates with an air suction path (not shown) of the film suction hole 170. The air suction path is formed through a gap between the upper mold cavity insert 130 and the upper mold chase 110. In addition, the gap portion 190 between the ejector pin 140 and the pin hole 150 constitutes an air adsorbing portion around the tip protruding portion of the ejector pin 140.

  In this way, by connecting the gap portion 190 between the ejector pin 140 and the pin hole 150 to the air suction path, the release film 180 around the protruding portion of the ejector pin 140 protruding from the parting surface of the upper mold cavity insert 130 is removed. Adsorption can be held. As a result, the ejector pins 140 are provided in the mold 300 using the release film 180 to improve the releasability of the molded product, and the release film 180 covering the ejector pins 140 protruding from the mold parting surface is attached to the ejector pins. It can be adsorbed and held in close contact with the parting surface of the mold around the tip protruding portion of 140. Further, the peripheral edge portion of the tip of the ejector pin 140 is formed in a so-called R-surface shape (R shape or curved surface shape), so that even if the release film 180 covering the periphery of the protruding portion of the ejector pin 140 is stretched, it is damaged. Never do.

  The lower mold cavity insert 210 constituting the lower mold 200 is air-adsorbed with a wiring substrate 420 mounted with a semiconductor chip 410 as a molded product in alignment with the cavity recess 120 formed in the upper mold 100. A substrate suction unit 220 is provided. The substrate suction unit 220 communicates with an air suction path of the upper mold 100 or an air suction path (both not shown) provided in the lower mold 200. An air suction path (not shown) is connected to decompression means such as a vacuum pump. The lower mold 200 is provided with known mold parts such as a center insert, a pot insert and a lower mold chase block in addition to the lower mold cavity insert 210.

  An example of the resin molding operation by the mold 300 described above will be described with reference to FIGS. The mold 300 includes a known mold opening / closing mechanism that moves at least one of the upper mold 100 and the lower mold 200 constituting the mold 300 in contact with and separated from each other.

First, as shown in FIG. 2, the wiring board 420 on which the semiconductor chip 410 is mounted is set at a predetermined position of the lower mold cavity insert 210 when the mold 300 is in the mold open state. The wiring board 420 set in the lower mold cavity insert 210 is sucked by air from the air suction path communicating with the board suction part 220 and is sucked by air.
The release film 180 is unwound so as to cover the parting surface of the upper mold cavity block 130 by a film transport mechanism (not shown) provided in the resin mold apparatus, and is drawn to the parting surface. At this time, the ejector pin 140 protrudes downward from the pin hole 150.

  The release film 180 is adsorbed and held on the mold parting surface of the upper mold 100 (the clamp surface of the wiring board 420 and the cavity recess 120) by the film adsorption holes 170 and the gap portions 190 of the upper mold 100. At this time, the release film 180 covering the ejector pin 140 protruding from the mold parting surface is sucked and held in a state of being in close contact with the mold parting surface around the protruding portion of the ejector pin 140.

  Next, the mold 300 is closed as shown in FIG. At this time, the ejector pins 140 are pressed back so as to contact the wiring board 420 set on the lower mold 200 via the release film 180 and compress the spring 160. That is, the position of the tip portion (lower end portion in the drawing) of the ejector pin 140 is flush with the clamp surface of the wiring board 420 (hereinafter sometimes simply referred to as a clamp surface). Since the air suction by the film suction hole 170 and the gap portion 190 is continuously performed, an excessive portion of the portion protruding from the clamp surface of the ejector pin 140 can be reduced. Thus, even if the ejector pin 140 is retracted into the pin hole 150, the release film 180 that is in close contact with the outer periphery of the pin does not wrinkle toward the cavity recess 120 side.

  That is, the release film 180 at the time of clamping is sucked in a state along the clamp surface of the upper mold 100 including the cavity recess 120. Even if the wrinkle of the release film is generated, the amount of the wrinkle is small, and the wrinkle generation location is sufficiently far from the cavity recess 120 that is the product. It does not reach the position in the cavity recess 120. As described above, since the release film 180 is in close contact with the clamp surface, the sealing resin 500 can be filled in a state in which the shape of the cavity recess 120 maintains the shape as designed.

  Next, as shown in FIG. 4, after the mold 300 is clamped, a plunger (not shown) is driven, and the sealing resin melted in the pot is transferred to the cavity recess 120 via a cull portion and a runner (not shown). Pump. The sealing resin 500 filled in the cavity recess 120 is thermally cured by heating and pressurizing the mold 300 in a clamped state, and a resin sealing portion (package portion) 510 is formed as shown in FIG. The

  After the semiconductor chip 410 is resin-molded, the mold 300 is opened as shown in FIG. When mold opening is performed, the ejector pin 140 is pushed out from the pin hole 150 by the urging force of the spring 160, and the ejector pin 140 protrudes from the parting surface of the upper mold cavity insert 130 toward the wiring board 420. At this time, the wiring substrate 420 remains adsorbed on the substrate adsorbing unit 220. Therefore, as the mold opening progresses, the protruding amount of the ejector pins 140 increases, and the separation between the release film 180 and the resin sealing portion 510 is promoted, and the release film 180 and the molded product 400 are reliably released. Can do.

  Thereafter, the molded product 400 placed on the lower mold cavity insert 210 is released from the suction of the wiring substrate 420 by the substrate suction unit 220, and the molded product 400 is taken out of the mold die 300 by an unloader (not shown). FIG. 7 shows a molded product 400 taken out from the mold 300 and from which unnecessary resin is removed. The molded product 400 is separated into pieces by dicing or the like for each semiconductor chip 410 that is resin-sealed as necessary.

  Further, after the suction by the film suction hole 170 and the gap portion 190 of the upper mold cavity insert 130 is released and the release film 180 is separated from the parting surface, a new release film 180 is put on the upper mold cavity by a film transport mechanism (not shown). It conveys to the position which covers the parting surface of the insert 130.

According to this embodiment, if the mold 300 is opened after resin molding, the wiring board 420 is pushed down by the ejector pins 140, so that the release film 180 and the resin sealing portion 510 can be reliably released. .
In addition, since a gap 190 between the pin hole 150 into which the ejector pin 140 is inserted is connected to the air suction path, the release film 180 is closely attached around the tip protruding portion of the ejector pin 180 along the mold parting surface. Can be uniformly adsorbed and held.
Therefore, even when the ejector pin 140 is retracted into the pin hole 150 at the time of mold clamping, there is little surplus of the release film 180, and this surplus does not wrinkle in the cavity recess 120. Therefore, even if the ejector pins 180 are provided, the occurrence of molding defects of the molded product 400 can be reduced and the molding quality can be maintained.

(Second Embodiment)
Next, the configuration of the second embodiment of the mold 300 will be described. The same members as those in the first embodiment are denoted by the same reference numerals, and the description is incorporated. Here, the configuration different from the first embodiment will be mainly described.
FIG. 8A is a cross-sectional view of the main part in the vicinity of the ejector pin of the release film using mold according to the second embodiment, and FIG. 8B is a plan view of the upper mold cavity insert as viewed from below (B). is there.

  8A and 8B, the diameter dimension of the pin hole 150 of the ejector pin 140 of the present embodiment is the same as that of the first embodiment, but a suction groove 144 is formed on the outer peripheral surface of the ejector pin 140. The pins 140 are formed in the longitudinal direction. A plurality of suction grooves 144 are formed in the circumferential direction of the outer peripheral surface of the ejector pin 180, but as shown in FIG. 8A, it is limited to a linear shape provided at equal intervals in the circumferential direction of the ejector pin 140. Is not to be done. In this embodiment, in addition to the gap portion 191 between the pin hole 150 and the ejector pin 140, the suction groove 144 formed on the outer peripheral surface of the ejector pin 140 is also used as an air adsorbing portion. As a result, the clearance between the ejector pin 140 and the pin hole 150 is increased by the depth of the suction groove 144 to increase the air suction force, and the mold adhesion of the release film 180 covering the periphery of the tip protruding portion of the ejector pin 140 is increased. Can be increased.

(Third embodiment)
Next, the configuration of the third embodiment of the mold 300 will be described. The same members as those in the first embodiment are denoted by the same reference numerals, and the description is incorporated. Here, the configuration different from the first embodiment will be mainly described.
FIG. 9A is a cross-sectional view of a main part in the vicinity of an ejector pin of a release film using mold according to the third embodiment, and FIG. 9B is a plan view of the lower mold cavity insert.

As another example of the film suction hole 170 disposed in the vicinity of the ejector pin 140, as shown in FIG. 9, the upper mold cavity corresponding to the space between the pin hole 150 of the ejector pin 140 and the cavity recess 120 is shown. A film suction hole 171 connected to the air suction path may be provided on the parting surface of the insert 130. By adsorbing the release film 180 from the film adsorbing holes 171, the release film 180 is closely adhered between the tip protruding portion of the ejector pin 180 and the cavity concave portion 120 along the mold parting surface and uniformly adsorbed and held. can do.
Therefore, even when the ejector pin 140 is retracted into the pin hole 150 at the time of mold clamping, the excess of the release film 180 is small, so that wrinkles are not caught in the cavity recess 120.

In this embodiment, the film adsorbing portion 171 is provided separately from the pin hole 150 in which the ejector pin 140 is mounted. However, the gap portion 190 between the pin hole 150 and the ejector pin 140 described in the first embodiment is used together. Thus, the release film 180 can be air-adsorbed.
In addition, the suction groove 144 is formed on the outer peripheral surface of the ejector pin 140 described in the second embodiment, and the gap portion between the ejector pin 140 and the pin hole 150 is enlarged by the suction groove 144, and the ejector pin air adsorbing portion 191. It can also be used in combination.
In addition, although the front-end | tip peripheral part of the ejector pin 140 shown to FIG. 9 (A), (B) is not formed in what is called R shape (R surface shape or curved surface shape), it may be formed in what is called R shape. .

  As mentioned above, although it demonstrated in detail based on each embodiment of this invention, of course, it is not limited to each embodiment mentioned above. For example, not only a mold mold in which the upper mold cavity insert is covered with a release film but also a mold mold in which the lower mold cavity insert is covered with a release film may be used. Further, although the wiring substrate 420 on which the semiconductor chip 410 is mounted is illustrated as an object to be molded, an LED chip on which a light emitting diode is mounted in addition to the semiconductor chip 410 may be used. Of course, a lead frame or the like can be used as the wiring board.

100 Upper mold 120 Cavity concave portion 140 Ejector pin 144 Suction groove 150 Pin hole 160 Spring 170 Film adsorption hole 180 Release film 182 Stretching portion 184 Wrinkle 190 Gap portion 200 Lower mold 300 Release film using mold 400 Molded article 410 Semiconductor Chip 420 Wiring board 500 Molding resin 510 Resin molding part

Claims (5)

A mold that clamps a molded product while holding the release film on the mold parting surface including the cavity recess of the cavity insert and performs resin molding,
An ejector pin is provided in a pin hole provided on the suction surface of the mold parting surface on which the release film is sucked and held so as to face the wiring board portion other than the resin sealing portion of the molded product, The gap portion between the pin hole into which the ejector pin is inserted is connected to the air suction path, and the release film covering the ejector pin protruding from the mold parting surface when the mold die is open is the gap. A mold die that is sucked into an air suction path through the portion and is closely attached and held around the tip protruding portion of the ejector pin in accordance with the die parting surface.   2. The mold metal according to claim 1, wherein a suction groove connected to the air suction path is formed on an outer periphery of the ejector pin inserted into the pin hole along a longitudinal direction of the ejector pin. Type.   A suction hole for connecting to the air suction path is provided in a portion facing the outer edge of the wiring board other than the corner portion of the cavity recess provided in the cavity insert and the resin sealing portion of the workpiece. The mold according to claim 1 or 2.   The mold die according to any one of claims 1 to 3, wherein a peripheral edge portion of the tip of the ejector pin is formed in an R-surface shape. A mold that clamps a molded product while holding the release film on the mold parting surface including the cavity recess of the cavity insert and performs resin molding,
An ejector pin is provided on a mold parting surface on which the release film is adsorbed and held so as to face a wiring board portion other than a resin sealing portion of a molded product so as to protrude, and the ejector pin is The suction hole provided in the mold parting surface between the pin hole to be inserted and the cavity recess is connected to an air suction path, and the mold mold is opened from the mold parting surface when the mold is open. The release film covering the projecting ejector pin is sucked into the suction hole, and is closely held by suction following the mold parting surface between the tip projecting portion of the ejector pin and the cavity recess. Mold mold.