TWI597164B - Sheet-type resin body, resin molding apparatus, resin molding method and molding product manufacturing method - Google Patents

Description

Sheet-shaped resin body, resin molding device, resin molding method, and method of manufacturing the shaped product

The present invention relates to a sheet-like resin which is a resin material used in the production of a shaped product, a resin molding apparatus using a sheet-like resin, a resin molding method, and a method of producing a shaped product.

When a molded article is produced by using a molding die having a cavity, the sheet-shaped resin is used to produce a molded article by a compression molding technique (see, for example, Patent Document 1). One or a plurality of shaped articles are produced from a resin molded body formed by resin. Examples of the resin molded body include a resin sealing body having a unitary substrate, a wafer-shaped member (hereinafter referred to as a "wafer"), and a plurality of semiconductors mounted on a plurality of regions of the entire substrate. And a sealing resin comprising a hardening resin which covers a plurality of regions and is formed into a flat plate shape. The sheet-like resin supplied to the cavity is melted to form a molten resin (liquid resin), and the fluid resin is cured to form a cured resin.

The resin sealing body is formed into a sheet by a method such as cutting or the like in each of a plurality of regions of the substrate or a specific number of regions. Thereby, a finished product of an electronic component equivalent to a shaped article in each region or a specific number of regions is manufactured. As electronic zero Examples of the finished product include electronic components such as a semiconductor integrated circuit (IC), an optical semiconductor element such as an LED, and a transistor.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2006-256195 (Patent No. 1 and Figs. 2 to 3)

In recent years, first, the demand for miniaturization and thinning of electronic components has increased. Secondly, in order to increase the number of electronic components manufactured from one substrate, the demand for large-sized substrates has increased due to the demand for lower price. In order to satisfy the above two requirements, the formation space of the hardened resin, that is, the tendency of the cavity to be thinned and enlarged is increased.

According to the conventional technique described in Patent Document 1, first, the amount of the particulate resin material corresponding to the material of the sheet-like resin and supplied to the cavity is uneven, and the fluidity of the resin is relative to the volume of the cavity. The volume may be too much or insufficient. When the fluidity resin is excessive or insufficient, for example, the thickness of the sealing resin may be uneven, and voids may be generated in the sealing resin, and an unfilled portion (depression) may be formed on the surface of the sealing resin. Poor appearance may occur. Secondly, when the molten resin is produced by supplying the required amount of the particulate resin material into the cavity for resin sealing and heating and melting, bubbles may be generated inside the molten resin. In this case, the sealing resin may generate voids. Third, as the tendency of the cavity to be thinned increases, the following adverse effects caused by the particle size unevenness in the particulate resin material tend to occur. These adverse effects firstly refer to the flow of the flowing resin, and the fluidity The resin flows to cause the metal thin wires (wires) for wiring to be broken or the like. Secondly, the thickness of the sealing resin is uneven due to the difference in the degree of easy melting between the large-diameter particles and the small-diameter particles. In either of the above three cases, there is a problem that the yield of the electronic component is lowered.

Fourth, according to the prior art, the particulate resin material is pressed and flattened before the granular resin material is supplied into the cavity, whereby the shape of the resin material is maintained as a sheet-like resin material. shape. Therefore, there is a problem of increased working hours.

The above problem also occurs when a molded article other than an electronic component is produced by a compression molding technique using a sheet-like resin. Examples of the molded article other than the electronic component include optical components such as a lens having a cured resin containing a light-transmitting resin.

In order to solve the above problems, an object of the present invention is to provide a sheet-like resin body, a resin molding apparatus, a resin molding method, and a molded article which can improve yield and reduce man-hours when a molded article is produced by compression molding. method.

In order to solve the above problems, the sheet-like resin body of the present invention is characterized by comprising a sheet-like resin which is used as a resin material when a molded article is produced using a molding die having a cavity, and a first film which is closely provided to a first surface of the surface constituting the sheet-like resin; and a second film that is closely provided on the second surface facing the first surface; and at least one of the first film and the second film includes a functional film. When the functional film is taken out from the molding die and the resin molded body including the plurality of molded articles is taken out, the functional film functions as a release film; the functional film and the sheet-like resin at least partially overlap each other.

In the sheet-like resin body of the present invention, the first film and the second film are respectively provided on the first surface and the first surface of the sheet-like resin for the purpose of protecting the sheet-like resin. A protective film on both sides, at least one of the protective films being a functional film.

In the sheet-like resin body of the present invention, the sheet-like resin is pressed from the one end of the sheet-like resin to the other end to the functional film, whereby the sheet-like resin is present in the sheet-like resin. The gas between the functional film and the functional film is removed, and the sheet-like resin is adhered to the functional film.

The method for producing a sheet-like resin body of the present invention is a sheet-like resin which is used as a resin material when a molded product having a cavity is used to produce a molded product, and a first film which is closely provided to form a sheet. a first surface of the surface of the resin; and a second film that is closely disposed on the second surface facing the first surface; and at least one of the first film and the second film includes a functional film. When the resin film of the one or a plurality of molded articles is taken out from the molding die, the film functions as a release film, and has a step of disposing the functional film on the molding die so as to cover the cavity. a step of placing the sheet-like resin on the functional film in such a manner that at least a portion of the functional film overlaps at least a portion of the sheet-like resin; and sequentially sequentially from one end of the sheet-like resin to the other end The sheet-like resin is pressed to the functional film, whereby the gas existing between the sheet-like resin and the functional film is removed, and the sheet-like resin is adhered to the functional film.

The method for producing a sheet-like resin body of the present invention is a sheet-like resin which is used as a resin material when a molded product having a cavity is used to produce a molded product, and a first film which is closely provided to form a sheet. a first surface of the surface of the resin; and a second film that is closely disposed on the second surface facing the first surface; and at least one of the first film and the second film includes a functional film. When the resin film of the one or a plurality of molded articles is taken out from the molding die, the film functions as a release film, and has a step of overlapping at least a part of the functional film with at least a part of the sheet-like resin. In the state, the functional film and the sheet resin are supplied a step of applying to the forming mold; a step of placing the functional film and the sheet-like resin on the forming mold in such a manner that the overlapping portion covers the cavity; and sequentially taking the sheet from one end of the sheet-like resin to the other end The resin is pressed to the functional film, whereby the gas existing between the sheet-like resin and the functional film is removed, and the sheet-like resin is adhered to the functional film.

The resin molding apparatus of the present invention includes a first mold having a cavity, a second mold facing the first mold, a resin supply mechanism for supplying the sheet-like resin to the cavity, and a supply of the release film to the cavity. A resin supply body comprising a cured resin formed by curing a sheet-like resin after being melted in a cavity, and a resin molding apparatus comprising: an arrangement mechanism for causing a release film a sheet-like resin is placed on the release film at least partially overlapping at least a portion of the sheet-like resin, and a pressing mechanism that sequentially presses the sheet-like resin from the one end of the sheet-like resin to the other end to the release film. Thereby, the gas existing between the sheet-like resin and the release film is removed, and the sheet-like resin is adhered to the release film.

In the resin molding apparatus of the present invention, the resin molding apparatus includes a conveying mechanism that also serves as a resin supply mechanism, a film supply mechanism, and an arrangement mechanism, and the conveying mechanism is in a state where the sheet-like resin is placed on the release film. The release film and the sheet resin are transferred to the cavity.

In the resin molding apparatus of the present invention, in the resin molding apparatus, the outline of the sheet-like resin projected to the opening of the cavity exceeds at least a part of the opening of the cavity, and the first die is formed on the outside of the cavity. The groove; the remaining resin in the molten resin that is not completely contained in the cavity is accommodated in the groove.

The resin molding method of the present invention comprises the steps of supplying a release film to a cavity of a molding die, the molding die including a first die having a cavity, and a phase of the first die a second mold facing the second mold; a step of supplying the sheet-like resin to the cavity; a step of melting the sheet-like resin in the cavity to form a molten resin; a step of sandwiching the first mold and the second mold; and melting the resin a step of forming a hardened resin by hardening; a step of opening the first mold and the second mold; and a step of taking out a resin molded body having a cured resin; and characterized in that at least a part of the functional film and the sheet-like resin are used a step of placing the sheet-like resin on the release film in a manner of at least partially overlapping; and sequentially pressing the sheet-like resin from the one end of the sheet-like resin to the other end to the release film, whereby the sheet-like resin is present The gas is removed from the release film, and the step of adhering the sheet resin to the release film is carried out.

The resin molding method of the present invention is characterized in that in the resin molding method, the step of supplying the release film to the cavity and the step of supplying the sheet resin to the cavity are shared; in the step of sharing, After the sheet-like resin is placed on the release film, the sheet-like resin and the release film are transferred to the cavity.

In the resin molding method of the present invention, in the resin molding method, the contour of the sheet-like resin projected to the opening of the cavity exceeds at least a portion of the opening of the cavity; and the first die and the second die are sandwiched In the step, the remaining resin which is not completely contained in the cavity in the molten resin is accommodated in the groove formed on the outer side of the cavity in the first mold.

The method for producing a shaped article of the present invention has the step of supplying a release film to a cavity of a molding die, the molding die including a first die having a cavity and a second die facing the first die a step of supplying the sheet-like resin to the cavity; a step of melting the sheet-like resin in the cavity to form a molten resin; a step of sandwiching the first die and the second die; and curing the molten resin to form a cured resin a step of opening the first mold and the second mold; a step of taking out the resin molded body having the cured resin; and manufacturing the resin molded body into individual pieces a step of forming a product; the step of placing a sheet-like resin on the release film in such a manner that at least a portion of the release film overlaps at least a portion of the sheet-like resin; and from one end of the sheet-like resin to the other The one end of the sheet-shaped resin is pressed to the release film in this order, whereby the gas existing between the sheet-like resin and the release film is removed, and the sheet-like resin is adhered to the release film.

The method for producing a shaped article of the present invention is characterized in that in the method for producing the shaped article, the step of supplying the release film to the cavity and the step of supplying the sheet resin to the cavity are shared; In the step, after the sheet-like resin is placed on the release film, the sheet-like resin and the release film are transferred to the cavity.

In the method for producing a shaped article of the present invention, in the method for producing a shaped article, the contour of the sheet-like resin projected to the opening of the cavity exceeds at least a portion of the opening of the cavity; and the first die is In the step of sandwiching the second mold, the remaining resin which is not completely contained in the cavity in the molten resin is accommodated in the groove formed on the outer side of the cavity in the first mold.

According to the present invention, it is possible to obtain a sheet-like resin body which is a sheet-like resin body which is adhered to a functional film which functions as a release film when the resin molded body is taken out from the molding die, and is characterized in that: The sheet-like resin and the functional film are sequentially pressed from one end of the sheet-like resin to the other end, whereby the gas existing between the sheet-like resin and the functional film is removed. By using such a sheet-like resin body, first, it is possible to suppress thickness unevenness, bubble, and surface depression of the cured resin in the resin molded body due to the gas existing between the sheet-like resin and the functional film. Wait. Further, it is possible to prevent adverse effects caused by uneven particle diameters as compared with the case of using a particulate resin material. Thereby, the yield at the time of manufacturing a molded product can be improved.

Secondly, a sheet-like resin which is a sheet-like resin which is adhered to a functional film which functions as a release film when the resin molded body is taken out from the molding die is used, thereby eliminating the need for resin molding. The release film is supplied to the mold cavity. Therefore, the man-hours at the time of resin molding can be reduced.

According to the invention, at least one of the first film and the second film includes a release film. The release film functions as a protective film which is attached to the opposing surface of the surface constituting the sheet-like resin for the purpose of protecting the sheet-like resin. Therefore, the following steps can be omitted, which means that at least one protective film is peeled off from the sheet-like resin before the resin molding is performed. Therefore, the man-hours at the time of resin molding can be reduced.

1‧‧‧Down mold (1st mold, 2nd mold)

2‧‧‧Upper mold (2nd mold, 1st mold)

3‧‧‧forming mould

4‧‧‧ cavity

5, 42‧‧‧ sheet resin

6, 28‧‧‧ release film (functional film, first film, second film)

7‧‧‧ Sealing the front substrate

8‧‧‧Whole substrate

9‧‧‧ wafer

10‧‧‧ wire

11‧‧‧ imaginary line

12‧‧‧ Area

13, 21‧‧‧ suction holes

14, 23, 38‧‧‧ Inhaled gas

15‧‧‧ molten resin

16, 50‧‧‧ sealing resin

17, 30, 51‧‧‧ resin sealing body (resin molded body)

18‧‧‧ platform

19‧‧‧Rotary knife

20‧‧‧Adsorption recess

22‧‧‧ clearance slot

24‧‧‧Electronic parts (formed products)

25‧‧‧ separate substrate

26‧‧‧Single sealing resin

27‧‧‧Corner-shaped concave and convex

29‧‧‧Corner-shaped concave-convex resin

31‧‧‧Workbench

32‧‧‧Transporting jig (resin supply mechanism, film supply mechanism)

33‧‧‧ Space

34‧‧‧Rotary shaft (pressing mechanism)

35‧‧‧Rotating roller (pressing mechanism)

36‧‧‧ gas

37‧‧‧sucking mechanism

39‧‧‧Exhaust gas

40‧‧‧Scraper

41‧‧‧Sheet resin with protective film

43‧‧‧Protective film (1st film, 2nd film)

44‧‧‧Protective film, release film (functional film, second film, first film)

45‧‧‧Overlap

46‧‧‧ slots

47‧‧‧ Remaining resin

48‧‧‧ Thin path

49‧‧‧The recess of the release film

52‧‧‧Sheet Department

53‧‧‧ Protrusion

54‧‧‧Protruding

55‧‧‧No resin department

D1, d2‧‧ ‧ step difference

Fig. 1 is a schematic cross-sectional view showing a resin molding method using a sheet-like resin of the present invention in order of steps.

2(1) and (2) are schematic cross-sectional views showing a resin molding method in accordance with the order of steps, followed by Fig. 1 . (3) and (4) are schematic cross-sectional views showing a modification of the resin molding method using the sheet-like resin of the present invention in the order of steps.

Fig. 3 (1) is a perspective view showing a step of sequentially pressing the sheet-like resin from the one end of the sheet-like resin to the other end to the release film when the sheet-like resin body of the present invention is produced or used. (2) is a schematic cross-sectional view showing a state in which the sheet-like resin of the present invention is transferred to a cavity.

4(1) and (2) show the outline of one method of sequentially pressing the sheet-like resin from one end of the sheet-like resin to the other end to the release film when the sheet-like resin body of the present invention is produced or used. Sectional view. (3) is a schematic cross-sectional view showing another method of pressing the sheet-like resin to the release film.

Fig. 5 is a schematic cross-sectional view showing a resin molding method using a sheet-like resin of the present invention, that is, a sheet-like resin having a protective film which also serves as a release film.

6 is a schematic cross-sectional view showing a resin molding method using a sheet-like resin of the present invention, that is, a sheet-like resin having a planar shape in which a cavity is planar, and containing the remaining resin, in accordance with the procedure of the steps. In the step of the slot.

A release film 6 which is provided in close contact with the lower surface of the sheet-like resin 5 is provided in the sheet-like resin 5, and the sheet-like resin 5 is used as a resin material when a molded article is produced using the molding die 3 having the cavity 4. . The sheet-like resin 5 is sequentially pressed from the one end to the other end to the release film 6, whereby the gas 36 existing between the sheet-like resin 5 and the release film 6 is removed, and the sheet-like resin 5 and the release film are removed. 6 close. In a state in which the sheet-like resin 5 and the release film 6 are adhered to each other, the entire release film 6 and the sheet-like resin 5 are simultaneously conveyed and supplied to the cavity 4.

[Example 1]

An embodiment of the resin molding apparatus of the present invention will be described with reference to Figs. 1 and 2 (1), (2) and Fig. 3 . The resin molding apparatus uses a sheet-like resin as a resin material to mold a sealing resin for resin sealing a wafer mounted on the substrate. As shown in Fig. 1 (1), a molding die 3 having a lower mold 1 and an upper mold 2 is provided in a resin molding apparatus. A cavity 4, which is a space formed by a recess, is provided in the lower mold 1. The sheet-like resin 5 containing a thermosetting resin is supplied from the outside of the forming die 3 to the cavity 4. The sheet-like resin 5 is placed on the release film 6, and the release film 6 and the sheet-like resin 5 are simultaneously supplied to the cavity 4 in a state where the sheet-like resin 5 and the release film 6 are adhered.

As described below, in the present embodiment, the sheet-like resin 5 shown in Fig. 1 (1) is pressed from the one end of the sheet-like resin 5 to the other end to the release film 6 outside the molding die 3. By pressing The sheet-like resin 5 excludes the gas existing between the sheet-like resin 5 and the release film 6. Then, the sheet-like resin 5 is supplied to the cavity 4 in a state of being adhered to the release film 6.

Further, in the present application, the space formed by the concave portion provided in the lower mold 1 is referred to as a cavity 4 itself. Further, for convenience, a space for forming a hardened resin which is formed by covering the space by the release film 6 is also referred to as a cavity 4.

As shown in Fig. 1 (1), the pre-sealed substrate 7 is fixed to a mold surface (a lower surface in the drawing) of the upper mold 2 by a well-known method such as suction and clamping. The front substrate 7 is sealed to have a unitary substrate 8 and a wafer 9. The terminals of the entire substrate 8 and the wafer 9 are electrically connected to each other by the wires 10. The entire substrate 8 is divided into a plurality of regions 12 in a lattice shape by an imaginary line 11.

As shown in Figs. 1 (1) and (2), a plurality of suction holes 13 are provided in the lower mold 1. A plurality of suction holes 13 are connected to a suction source (not shown) such as a suction pump. The release film 6 on which the sheet-like resin 5 is placed is adsorbed to the die face of the cavity 4 by suction of the gas 14. The release film 6 is heated by a heater (not shown) provided in the lower mold 1 to be soft. Therefore, the release film 6 is elongated toward the outer edge of the cavity 4 by the suction of the gas 14, and is adsorbed to the die face of the cavity 4 in a state of no wrinkles.

An embodiment of a resin molding method using the sheet-like resin 5 of the present invention will be described with reference to Fig. 1 and Figs. 2 (1) and (2). First, as shown in Fig. 1 (1), the sheet-like resin 5 placed in the state of being placed on the release film 6 is supplied from the outside of the mold 3 to the cavity 4. The release film 6 on which the sheet-like resin 5 is placed is adsorbed to the die face of the cavity 4 by the suction gas 14. Thereby, gas is prevented from remaining between the release film 6 and the die face of the cavity 4.

Next, as shown in Fig. 1 (2), the sheet-like resin 5 is heated by a heater (not shown) provided in the lower mold 1, and the sheet-like resin 5 is melted. Thereby, the molten resin 15 is produced.

Next, as shown in Fig. 1 (3), the lower mold 1 is raised and lowered relative to the upper mold 2, and the lower mold is lowered. The die 1 is sandwiched by the upper die 2. Thereby, first, the entire substrate 8 is sandwiched by using the lower mold 1 and the upper mold 2. Second, the wafer 9 mounted on the unitary substrate 8 and the wire 10 are immersed (immersed) in the molten resin 15.

Next, as shown in Fig. 1 (4), the molten resin 15 is continuously heated, whereby the molten resin 15 is cured to form a sealing resin 16 containing a cured resin. Thereby, the resin sealing body 17 having the integral substrate 8, the wafer 9, the wire 10, and the sealing resin 16 is completed. The resin sealing body 17 corresponds to a resin molded body. The lower mold 1 and the upper mold 2 are opened, and the resin sealing body 17 is taken out from the mold surface of the upper mold 2. The surface shape of the release film 6 is transferred to the surface of the sealing resin 16. Therefore, when the surface shape of the release film 6 is a mirror surface, the surface of the sealing resin 16 can be mirror-finished.

Next, as shown in Fig. 2 (1), the resin sealing body 17 is conveyed to a stage 18 of a chip forming apparatus such as a cutter. The sheet forming device has a cutting means such as a rotary blade 19. The platform 18 is provided with a plurality of adsorption recesses 20 for adsorbing the resin sealing body 17 in each of the regions 12, and a plurality of suction holes 21 connected to the adsorption recesses 20, respectively. Further, a clearance groove 22 is provided in the platform 18, and the clearance groove 22 accommodates the outer peripheral end of the rotary blade 19. The resin sealing body 17 is adsorbed to the upper surface of the stage 18 by using the suction gas 23 through a plurality of suction holes 21.

Next, as shown in Figs. 2 (1) and (2), cutting water (not shown) is supplied to the contact portion between the rotary blade 19 and the resin sealing body 17 while rotating the blade 19, along the respective imaginary lines 11 The resin sealing body 17 is cut. Thereby, the resin sealing body 17 is piece-formed, and the finished product of the several electronic component 24 is manufactured. Each electronic component 24 has a separate substrate 25, a wafer 9, a wire 10, and a separate sealing resin 26. The excess portion (the left end portion and the right end portion in the drawing) of the resin sealing body 17 is removed by the cutting water during the process of forming the resin sealing body 17 into pieces.

In the present embodiment, a modification shown in Figs. 2 (3) to (4) can be employed. In the present modification, as shown in Fig. 2 (3), a release film 28 is used, and the release film 28 is formed on the surface with minute A pyramid-shaped uneven portion 27. As shown in Fig. 2 (4), the resin film is formed by using the release film 28, whereby the resin sealing body 30 in which the uneven pyramid-shaped uneven resin 29 is formed on the surface of the sealing resin 16 is completed. This modification can be adopted when the wafer 9 is a light-emitting element such as an LED. The minute pyramid-shaped uneven resin 29 functions as a scattering portion that scatters light emitted from the LED.

According to this modification, when the surface shape of the release film 28 is transferred to the surface of the sealing resin 16 of the resin sealing body 30, the gas is suppressed from being present on the surface of the sealing resin 16. Therefore, for example, generation of minute depressions caused by the gas existing on the surface of the sealing resin 16 is suppressed. Instead of the minute pyramid-shaped uneven portion 27 in the present modification, finer irregularities can be formed on the surface of the release film 28. In this case, the surface of the sealing resin 16 can be matted.

The step of pressing the sheet-like resin 5 shown in Fig. 1 (1) to the release film 6 from the outside of the molding die 3 until it is supplied to the cavity 4 will be described with reference to Fig. 3 . As shown in Fig. 3 (1), first, a rectangular release film 6 is placed on the table 31. The release film 6 is pulled toward the outer periphery, and the release film 6 is adsorbed on the upper surface of the table 31. Thereby, the release film 6 in a state of no wrinkles can be adsorbed to the upper surface of the table 31.

Then, the outer edge portion of the rectangular release film 6 is pressed by, for example, a frame-shaped transfer jig 32. Then, the sheet-like resin 5 is placed on the release film 6 in the space 33 surrounded by the transfer jig 32.

Next, as shown in Fig. 3 (1), the sheet-like resin 5 is pressed from the one end of the sheet-like resin 5 to the other end in order (from the right side to the left side in the drawing) to the release film 6. The sheet-like resin 5 is pressed to the release film 6 by using the rotating roller 35 having the rotating shaft 34. Thereby, the gas 36 existing between the sheet-like resin 5 and the release film 6 outside the molding die 3 is excluded from between the sheet-like resin 5 and the release film 6.

Next, as shown in Fig. 3 (2), the release film 6 is sucked by the suction gas 37 by a suction mechanism (not shown). The release film 6 is stopped from being adsorbed on the upper surface of the table 31. Thereby, the release film 6 in the state of the wrinkle-free state is adhered to the lower surface of the frame-shaped conveyance jig 32.

Next, the frame-shaped conveyance jig 32 is conveyed to the upper side of the cavity 4 by using a conveyance mechanism (not shown). Then, the suction by the suction mechanism 37 is released, and the release film 6 is adsorbed to the mold surface of the cavity 4 by the suction gas 14 shown in Fig. 1 (1). The state before the release of the release film 6 is as shown in Fig. 1 (1) (the conveyance jig 32 shown in Fig. 3 (1) is not shown).

According to the present embodiment, the sheet-like resin 5 is pressed outside the molding die 3, whereby the gas 36 (see Fig. 3 (1)) existing between the sheet-like resin 5 and the release film 6 is removed. Then, in a state in which the sheet-like resin 5 is adhered to the release film 6, the entire release film 6 and the sheet-like resin 5 are supplied to the cavity 4. By the first effect, the thickness of the sealing resin 16 (hardened resin) of the resin sealing body 17 (resin molded body) which is generated by the gas 36 existing between the sheet-like resin 5 and the release film 6 can be suppressed. Unevenness, bubbles, depressions on the surface, etc.

In addition, as a second effect, the following effects due to the exclusion of the gas 36 (see FIG. 3 (1)) existing between the sheet-like resin 5 and the release film 6 outside the molding die 3 can be obtained. This effect is such that, even when the sheet-like resin 5 has the following characteristics, it is possible to reliably present the sheet-like resin 5 (in other words, the sheet-like resin 5 which has not yet started to be melted) which has not been heated to the outside of the mold 3. The gas 36 between the release films 6 is excluded, and the above characteristics mean that the reaction caused by the heating of the sheet-like resin 5 starts to occur in a short time.

[Embodiment 2]

Another embodiment of the resin molding method of the present invention using the sheet-like resin 5 will be described with reference to Fig. 4 example. In FIG. 4, the illustration of the conveyance jig 32 shown in FIG. 3 (1) is abbreviate|omitted.

The present embodiment is characterized in that the release film 6 which is heated and softened is adsorbed on the mold surface of the cavity 4, and the sheet-like resin 5 is placed on the adsorbed release film 6, and then in the cavity 4. Inside, the sheet-like resin 5 is pressed to the release film 6. Thereby, first, gas is prevented from remaining between the release film 6 and the die face of the cavity 4. Second, in the inside of the cavity 4, the gas existing between the sheet-like resin 5 and the release film 6 in a state before the start of melting can be surely removed as the exhaust gas 39. This embodiment is particularly effective in the case where the sheet-like resin 5 has the following characteristics, which means that the reaction caused by the heating of the sheet-like resin 5 does not start to occur in a short time.

In the present embodiment, as shown in Figs. 4(1) and 4(2), the sheet-like resin 5 is pressed to the release film 6 by using the rotary roller 35 having the rotary shaft 34. Alternatively, as shown in Fig. 4 (3), the sheet-like resin 5 may be pressed to the release film 6 by using a squeegee 40 composed of a plate member. The sheet-like resin 5 can also be pressed to the release film 6 by using a roll that does not rotate. In other embodiments, the above means of pressing the sheet-like resin 5 can also be used.

[Example 3]

Another embodiment of the sheet-like resin of the present invention and a resin molding method using the sheet-like resin will be described with reference to Fig. 5 . As shown in FIG. 5, the sheet-like resin 41 with a protective film in the present embodiment has a sheet-like resin 42 and a protective film 43 adhered to the upper surface of the sheet-like resin 42 and adhered to the lower surface of the sheet-like resin 42. Protective film 44. Each of the protective films 43, 44 has the following functions. These functions are a function of protecting the sheet-like resin 42 from external force, a function of preventing dust from adhering to the sheet-like resin 42, a function of preventing the sheet-like resin 42 from adhering to each other, and a function of easily processing a plurality of sheet-like resins 42.

The protective film 43 is formed according to an appropriate method described with reference to FIGS. 3 and 4. 44 is adhered to the sheet resin 42. Thereby, the gas between the upper surface of the sheet-like resin 42 and the protective film 43, and the gas between the lower surface of the sheet-like resin 42 and the protective film 44 are removed in advance. The protective film 44 on the lower surface of the sheet-like resin 42 functions as the release film 44. Therefore, the thickness unevenness of the cured resin of the resin molded body, the bubbles, the depression of the surface, and the like which are generated by the gas existing between the sheet-like resin 42 and the protective film 44 as the release film 44 can be suppressed. The sheet-like resin 42 and the protective film 43 and the protective film (release film) 44 which are adhered to the upper surface and the lower surface of the sheet-like resin 42 respectively constitute the sheet-like resin body of the present invention.

The present embodiment is characterized in that the protective film 44 on the lower surface of the sheet-like resin 42 functions as the release film 44. The protective film 44 on the lower surface of the sheet-like resin 42 has the size and shape of the cavity 4 shown in Fig. 5 (2) in a complete view. Further, in the present application, the term "in-package in a plan view" includes a case where the objects to be compared have the same planar shape and completely overlap each other in plan view. The phrase "completely inclusive when viewed from the top" means that the plane shape of the other object in the contrast object is completely contained inside the planar shape of one side.

First, as shown in Fig. 5 (1), the protective film 43 is peeled off from the upper surface of the sheet-like resin 42 outside the molding die 3. Then, as shown in Fig. 5 (2), the release film 44 and the sheet-like resin 42 in the state in which the sheet-like resin 42 is adhered to the release film 44 are supplied from the outside of the mold 3 to the cavity 4. Next, as shown in Fig. 5 (3), the sheet-like resin 42 is heated by a heater (not shown) provided in the lower mold 1, and the sheet-like resin 42 is melted. Thereby, the molten resin 15 is produced.

Next, as shown in Fig. 5 (4), the lower mold 1 and the upper mold 2 are lifted and lowered, and the lower mold 1 and the upper mold 2 are sandwiched. Thereby, first, the entire substrate 8 is sandwiched by using the lower mold 1 and the upper mold 2. Second, the wafer 9 mounted on the unitary substrate 8 and the wire 10 are immersed (immersed) in the molten resin 15. Hereinafter, in the same manner as the steps described with reference to FIGS. 1(4) to 2(2), the complex shown in FIG. 2(2) is produced. A finished product of several electronic parts 24.

According to the present embodiment, the protective film 44 on the lower surface of the sheet-like resin 42 functions as the release film 44. The gas between the lower surface of the sheet-like resin 42 and the release film 44 is removed in advance. By this, it is possible to suppress thickness unevenness, bubbles, surface depressions, and the like of the cured resin of the resin molded body which is generated by the gas existing between the sheet-like resin 42 and the release film 44.

According to the present embodiment, it is not necessary to exclude the gas existing between the sheet-like resin 42 and the release film 44 in the resin molding apparatus and the resin molding step. Further, it is not necessary to peel off the protective film 44 from the sheet-like resin 42. Therefore, first, the mechanism of the resin molding apparatus can be simplified. Second, the man-hour of the resin forming step can be reduced.

In the present embodiment, the protective film 44 that functions as the release film 44 on the lower surface of the sheet-like resin 42 is used to have the size of the cavity 4 shown in Fig. 5 (2) in a plan view. Shape protective film 44. Instead, first, it is possible to use the protective film 44 having the size and shape of the cavity 4 partially covered in a plan view. For example, the protective film 44 having the size and shape of the inner cavity 4 in plan view can be used in the lateral direction (the right direction and the left direction) in FIG. 5 (2). In this case, the protective film 44 protrudes beyond the right side and the left side of the side of the cavity 4 to the outside of the cavity 4.

Further, the protective film 44 having the size and shape of the inner cavity 4 in a plan view in the right direction and the near direction in Fig. 5 (2) can be used. In this case, the protective film 44 protrudes beyond the side of the right side and the front side of the side of the cavity 4 toward the outside of the cavity 4. In such a case, the overlapping area of the cavity 4 and the protective film 44 may be expanded to such an extent that the protective film 44 does not interfere with the protective film and the release film.

Second, it is possible to use a protective film 44 having a cavity 4 The bottom surface has the same size and shape and functions as the release film 44. The "protective film 44 having the same size and shape" includes "a size and a shape having a degree that does not hinder the function as a protective film and a release film, that is, protection of a size and shape smaller than the bottom surface of the cavity 4. membrane". Even when such a protective film 44 is used, uneven thickness, bubbles, and surface of the cured resin of the resin molded body due to the gas existing between the sheet-like resin 42 and the release film 44 can be suppressed. The depression and so on. Further, since the protective film 44 functions as the release film 44, it is not necessary to peel off the protective film 44 from the sheet-like resin 42.

In the present embodiment, the protective film 43 is peeled off from the upper surface of the sheet-like resin 42 outside the molding die 3. Alternatively, the protective film 43 may be peeled off from the upper surface of the sheet-like resin 42 inside the molding die 3.

[Example 4]

Another embodiment of any one of the sheet-like resin of the present invention, the resin molding apparatus using the sheet-like resin, and the resin molding method will be described with reference to Fig. 6 . The features of this embodiment are as follows. First, as shown in Figs. 6 (1) and (2), the sheet-like resin 42 has the size and shape of the inner cavity 4 completely in plan view. In other words, in a state where the sheet-like resin 42 has been supplied to the cavity 4, the sheet-like resin 42 completely exceeds the outer edge of the cavity 4 in plan view. Therefore, the overlapping portion 45 in which the sheet-like resin 42 is superposed on the mold surface outside the cavity 4 is formed at the entire end portion of the sheet-like resin 42.

Second, in the lower mold 1, a groove 46 is provided in such a manner as to completely surround the cavity 4 in a plan view and completely enclose the release film 44.

Third, the size and shape of the sheet-like resin 42 are determined such that the volume of the molten resin 15 which is formed by melting the sheet-like resin 42 exceeds the volume of the cavity 4 by an appropriate amount. The "appropriate amount" associated with the volume of the molten resin 15 corresponds to the sheet at the overlapping portion 45 shown in Fig. 6 (2). The volume of the resin 42. In a state in which the lower mold 1 and the upper mold 2 are sandwiched, the remaining resin 47 containing the excess amount of the molten resin 15 in an amount exceeding the volume of the cavity 4 flows in the thin passage 48 on the die surface of the lower mold 1. And flows into the slot 46.

Fourth, the position, width and depth of the groove 46 are determined in the following manner. The position, width and depth of the groove 46 are determined such that the excess resin 47 that exceeds the volume of the cavity 4 is hardened in the thin passage 48 and the groove 46. The outer side of the groove 46 is raised by the step d1 (refer to the figure on the right side of the center line CL drawn on the side of the lower mold 1 in FIGS. 6(2) to (4)) so that the molten resin as the remaining resin 47 is made. 15 does not flow out to the outside of the groove 46. For example, about 10 to 50 μm can be used as the size of the step d1.

The resin molding method of this embodiment will be described with reference to Fig. 6 . First, as shown in Fig. 6 (1), the protective film 43 is peeled off from the upper surface of the sheet-like resin 42 outside the molding die 3.

Next, as shown in Fig. 6 (2), in the state where the sheet-like resin 42 has been placed on the release film 44 and adhered to the release film 44, the release film 44 and the sheet-like resin 42 are simultaneously integrated. The outside of the forming die 3 is supplied to the cavity 4. The overlapping portion 45 is formed at the end portion of the sheet-like resin 42 supplied to the cavity 4 (the left end portion and the right end portion are shown). Further, the upper portion of the groove 46 is completely covered by the release film 44.

Then, as shown in Fig. 6 (3), the sheet-like resin 42 is heated by a heater (not shown) provided in the lower mold 1, and the sheet-like resin 42 is melted, whereby the molten resin 15 is produced. Next, the lower mold 1 and the upper mold 2 are sandwiched. Thereby, the entire substrate 8 is sandwiched by the lower mold 1 and the upper mold 2, and the wafer 9 attached to the integral substrate 8 and the wires 10 are immersed (immersed) in the molten resin 15. The remaining resin 47 including the molten resin 15 overflowing from the cavity 4 flows into the groove 46 via the thin via 48. The remaining resin 47 overflowing from the cavity 4 flows into the concave of the release film 44 in the groove 46. Part 49 (also refer to Figure 6 (4)).

Next, as shown in Fig. 6 (3) and Fig. 6 (4), the molten resin 15 is continuously heated, whereby the molten resin 15 is cured to form a sealing resin 50 containing a cured resin. Thereby, the resin sealing body 51 having the integral substrate 8, the wafer 9, the wire 10, and the sealing resin 50 is completed. The lower mold 1 and the upper mold 2 are opened, and the resin sealing body 51 is taken out from the mold surface of the upper mold 2. Hereinafter, the finished products of the plurality of electronic components 24 shown in Fig. 2 (2) are manufactured in the same manner as the steps described with reference to Figs. 2 (1) and (2).

As shown in the right side of the center line CL drawn on the lower mold 1 side in Fig. 6 (4), a thin passage 48 is formed at the end portion of the resin sealing body 51 (refer to the right side of the center line CL in Fig. 6 (3) The thin plate portion 52 including the hardened resin and the protrusion 53 containing the hardened resin in the concave portion 49 of the release film 44. In the step shown in Fig. 2 (1), the thin plate portion 52 and the projections 53 are removed as redundant portions. Further, the height of the projection 53 is preferably smaller than the height of the sealing resin 50 for the reason that the resin sealing body 51 is easily conveyed or the like. Therefore, in the lower mold 1, the depth dimension of the groove 46 is preferably smaller than the depth dimension of the cavity 4.

According to the present embodiment, the remaining resin 47 is hardened on the outside of the cavity 4. Thereby, the sealing resin 50 is obtained in a space corresponding to the volume of the cavity 4 (accurately, the volume of the cavity 4 surrounded by the release film 44) in a state in which the molding die 3 is sandwiched. In other words, the sealing resin 50 having a volume obtained by subtracting the total volume of the plurality of wafers 9 from the volume of the cavity 4 surrounded by the release film 44 in a state where the molding die 3 has been sandwiched is obtained. .

Therefore, in addition to the effects of the respective embodiments described above, the following effects can be obtained. This effect is a case where a plurality of sealed front substrates 7 are resin-sealed, and even if the thickness of the wafer 9 and the size of the sheet-like resin 42 are not uniform, a uniform thickness can be obtained. Seal the resin 50. This effect is apparent when manufacturing the electronic component 24 having a small thickness of the sealing resin 50 (for example, having a thickness of 1.5 mm or less, more preferably 1.0 mm or less).

In the present embodiment, the following two modifications can be employed. First, a first modification will be described with reference to a diagram on the left side of the center line CL drawn on the lower mold 1 side in FIGS. 6(2) to (4). As shown on the left side of FIG. 6(2), the groove 46 formed in the lower mold 1 and the cavity 4 are compared with the height of the die face between the groove 46 and the outer side (the left side in the drawing) of the lower mold 1. The height of the die face increases by a step difference d2. Thereby, a projection 54 is formed between the groove 46 and the cavity 4. The protruding portion 54 is fitted into the release film 44, whereby the remaining resin 47 is suppressed from flowing back to the cavity 4. Further, in the portion of the resin sealing body 51 corresponding to the protruding portion 54, a resin-free portion 55 composed of a portion where the entire substrate 8 is exposed is formed. For example, a size of about 10 to 50 μm can be used as the step size, and about 0.3 to 1.0 mm can be used as the width of the upper surface of the protruding portion 54 (the size in the left-right direction in the drawing).

In the second modification, the heights of the die faces on both sides of the groove 46 shown in Fig. 6 are at the same position. This modification is not shown in FIG. 6. In this case, the height of the upper surface of the groove 46 is at the same position as the height of the upper surface of the cavity 4. Depending on the characteristics of the molten resin 15 (viscosity, ratio of filler, etc.), the configuration shown on the right side of Fig. 6 (2), the configuration shown on the left side of Fig. 6 (2), and a modification (not shown) are selected. Any of the components.

In the present embodiment, in a state where the sheet-like resin 42 has been supplied to the cavity 4, the sheet-like resin 42 completely encloses the cavity 4 in a plan view. Alternatively, the cavity 4 can be completely filled with the sheet-like resin 42 in a plan view, and the thickness of the sheet-like resin 42 can be increased. Thereby, the volume of the molten resin 15 which is formed by melting the sheet-like resin 42 can exceed the volume of the cavity 4 by an appropriate amount.

In the present embodiment, the sheet-like resin 42 may partially enclose the cavity 4 in a plan view. For example, when using the horizontal direction (the right direction and the left direction) in FIG. 6 (2), it has a plan view. A sheet-like resin 42 that encloses the size and shape of the cavity 4. In this case, the sheet-like resin 42 protrudes beyond the right side and the left side of the side of the cavity 4 toward the outside of the cavity 4. Grooves 46 are provided on the outer sides of the right side and the left side. Even in the case where the sheet-like resin 42 is used, the remaining resin 47 can be hardened in the groove 46 outside the cavity 4.

Further, the sheet-like resin 42 having the size and shape of the inner cavity 4 in a plan view in the right direction and the near direction in Fig. 6 (2) can be used. In this case, the sheet-like resin 42 protrudes to the outside of the cavity 4 beyond the right side and the near side of the side of the cavity 4. Grooves 46 are provided on the outer sides of the right side and the front side. Even in the case where the sheet-like resin 42 is used, the remaining resin 47 can be hardened in the groove 46 outside the cavity 4.

Further, in each of the embodiments described so far, the electronic component 24 as a molded article is produced by singulating the resin molded body. In the present application, the term "single piece" means that a plurality of shaped articles corresponding to the respective regions 12 are produced by singulating the resin molded body in a plurality of regions 12 as a unit. In addition, the term "segmentation" means that a resin molded body is cut to remove excess portions of the resin molded body, thereby producing a molded article.

The term "cutting" in the case of cutting the resin molded body includes, in addition to full cut, a half cut, and the resin molded body is broken by an external force.

The whole substrate 8 includes a printed circuit board (printed wiring board) which is a laminate including a lead frame such as copper or an iron-based alloy, a glass epoxy laminate, or a copper-coated polyimide film. As a substrate. Further, the unitary substrate 8 includes a ceramic substrate made of alumina, tantalum carbide, sapphire or the like, a metal base substrate made of a metal such as copper or aluminum, a glass base substrate made of glass as a base material, and a polyfluorene. The imine film or the like is a film base substrate of a substrate or the like. The wafer 9 includes a semiconductor integrated circuit (IC) and a light each in a wafer shape. Semiconductor components, transistors, diodes, resistors, capacitors, thermal resistors, and the like. In a region 12 of the unitary substrate 8, a wafer 9 can be mounted, and a plurality of wafers 9 can be mounted. The plurality of wafers 9 mounted in one region 12 may be of the same type or different types.

In each of the embodiments, the terminals of the entire substrate 8 and the wafer 9 are electrically connected to each other by wire bonding using the wires 10. Not limited to this, the terminals of the entire substrate 8 and the wafer 9 can be connected to each other by flip chip bonding.

A curing resin formed by curing with a thermosetting resin such as an epoxy resin or a polyoxyn resin is used as the sealing resins 16 and 50. When an optical semiconductor element such as an LED is used as the wafer 9, a light-transmitting resin is used.

In each of the embodiments, the sheet resin 5, 42 may be melted until the lower mold 1 and the upper mold 2 are sandwiched (for example, from the state shown in FIG. 1 (2) to FIG. 1 (3). In the period from the state shown, the inside of the cavity 4 is decompressed using a flow path (not shown) provided in the molding die 3. Thereby, the gas remaining inside the cavity 4 can be removed. Further, when the sheet-like resins 5 and 42 themselves are produced, when the sheet-like resins 5 and 42 contain air bubbles, the bubbles can be removed. Therefore, the yield at the time of producing a resin molded body can be further improved.

In each of the embodiments, the cavity 4 is placed in the lower mold 1. Not limited to this, the cavity 4 can be placed in the upper mold 2. In this case, the release films 6 and 44 may be placed on the upper surfaces of the sheet-like resins 5 and 42, and the release films 6 and 44 may be pressed to the sheet-like resins 5 and 42 to thereby form the sheet-like resin 5 . 42 is in close contact with the release film 6, 44. After the sheet-like resins 5 and 42 are adhered to the release films 6 and 44, the sheet-like resins 5 and 42 are heated. After the sheet-like resins 5 and 42 are heated and softened, the sheet-like resins 5 and 42 and the release film 6 and 44 adhered to the upper surface thereof can be conveyed without dropping the sheet-like resins 5 and 42.

Further, the cavity 4 can be disposed on both the die 1 and the upper die 2 as shown in Figs. 1, 5, and 6. In this case, both the protective film 44 adhered to the lower surface of the sheet-like resin 42 and the protective film 43 adhered to the upper surface shown in Fig. 5 (1) and Fig. 6 (1) function as a release film. Features.

The present invention is not limited to the case where the electronic component 24 is manufactured by resin sealing, and the present invention can be applied to the case of manufacturing an optical component such as a lens, an optical module, or a light guide plate by resin molding, or a general molding by a resin molded body. The situation of the product, etc. Even in such cases, the contents described so far can be applied.

The present invention is not limited to the above-described embodiments, and may be combined, changed, or selected as desired, without departing from the spirit and scope of the invention.

1‧‧‧Down mold (1st mold, 2nd mold)

4‧‧‧ cavity

5‧‧‧Sheet resin

6‧‧‧ Release film (functional film, first film, second film)

13‧‧‧ suction hole

31‧‧‧Workbench

32‧‧‧Transporting jig (resin supply mechanism, film supply mechanism)

33‧‧‧ Space

34‧‧‧Rotary shaft (pressing mechanism)

35‧‧‧Rotating roller (pressing mechanism)

36‧‧‧ gas

37‧‧‧sucking mechanism

38‧‧‧Inhalation gas

Claims (10)

A method for producing a molded article, comprising using a molding die having a cavity and using a sheet-like resin as a resin material, and performing resin molding to produce a shaped article, comprising the steps of: disposing the release film in such a manner as to cover the cavity a step of forming the above-mentioned molding die; a step of placing the sheet-like resin on the release film so that at least a part of the release film overlaps at least a part of the sheet-like resin; and the sheet-like resin In the state of being placed on the release film, the sheet-like resin is sequentially pressed from the one end of the sheet-like resin to the other end to the release film, whereby the sheet-like resin and the release film are present. The gas is removed, and the sheet-like resin is adhered to the release film; after the step of adhering, the step of molding the resin using the sheet-like resin is carried out using the molding die. A resin molding apparatus including a first mold having a cavity, a second mold facing the first mold, a resin supply mechanism for supplying the sheet-like resin to the cavity, and a release film to the mold A film-forming apparatus for producing a resin molded body comprising a cured resin formed by curing the sheet-like resin after being melted in the cavity, and comprising a disposing film for arranging the release film The sheet-like resin is placed on the release film so that at least a portion thereof overlaps with at least a portion of the sheet-like resin, and a pressing mechanism sequentially sequentially applies the sheet-like resin from one end of the sheet-like resin to the other end The film is pressed to the release film, whereby the gas existing between the sheet-like resin and the release film is removed, and the sheet-like resin is adhered to the release film. The resin molding apparatus according to claim 2, further comprising: a transfer mechanism that also serves as the resin supply mechanism, the film supply mechanism, and the arrangement mechanism; and the transfer mechanism in which the sheet-like resin is placed on the release film In this state, the release film and the sheet-like resin are transferred to the cavity. The resin molding apparatus according to claim 2, wherein the contour of the sheet-like resin projected to the opening of the cavity exceeds at least a portion of the opening of the cavity; and the first mold is formed in the first mold. a groove outside the cavity; the remaining resin of the molten resin not completely accommodated in the cavity is accommodated in the groove. A resin molding method comprising the steps of: supplying a release film to a cavity of a molding die, the molding die comprising a first die having the cavity, and a second die facing the first die; a step of supplying the sheet-like resin to the cavity; a step of melting the sheet-like resin in the cavity to form a molten resin; a step of sandwiching the first die and the second die; and hardening the molten resin a step of forming a cured resin; a step of opening the first mold and the second mold; and a step of taking out a resin molded body having the cured resin; and at least a part of the release film and the sheet a step of placing the sheet-like resin on the release film so that at least a part of the resin overlaps; and sequentially pressing the sheet-like resin from the one end of the sheet-like resin to the other end to the release film. Here, the gas existing between the sheet-like resin and the release film is removed, and the sheet-like resin is adhered to the release film. The resin molding method of claim 5, wherein the step of supplying the release film to the cavity and the step of supplying the sheet resin to the cavity are shared; in the step of sharing After the sheet-like resin is placed on the release film, the sheet-like resin and the release film are transferred to the cavity. The resin molding method of claim 5, wherein the contour of the sheet-like resin projected to the opening of the cavity exceeds at least a portion of the opening of the cavity; and the first mold and the second In the step of clamping the mold, the remaining resin of the molten resin that is not completely contained in the cavity is housed in a groove formed in the first mold and formed outside the cavity. A method for producing a shaped article, comprising the step of supplying a release film to a cavity of a molding die, the molding die comprising a first die having the cavity, and a second face facing the first die a step of supplying a sheet-like resin to the cavity; a step of melting the sheet-like resin in the cavity to form a molten resin; a step of sandwiching the first die and the second die; and melting the same a step of curing the resin to form a cured resin; a step of opening the first mold and the second mold; a step of taking out the resin molded body having the cured resin; and a step of forming the molded product into a molded product The step of placing the sheet-like resin on the release film so that at least a part of the release film overlaps at least a part of the sheet-like resin; and from one end of the sheet-like resin The other end sequentially presses the sheet-like resin to the release film, whereby the gas existing between the sheet-like resin and the release film is removed, and Make The step of adhering the sheet-like resin to the release film. The method for producing a shaped article according to the eighth aspect of the invention, wherein the step of supplying the release film to the cavity and the step of supplying the sheet resin to the cavity are shared; In the step, after the sheet-like resin is placed on the release film, the sheet-like resin and the release film are transferred to the cavity. The method of manufacturing a shaped article according to claim 8 or 9, wherein the contour of the sheet-like resin projected to the opening of the cavity exceeds at least a portion of the opening of the cavity; and the first die and the In the step of sandwiching the second mold, the remaining resin of the molten resin that is not completely contained in the cavity is housed in a groove formed in the first mold and formed outside the cavity.