JP2012248780A - Resin sealing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an art capable of enhancing the manufacturing yield of moldings.SOLUTION: A lower taper plate 25 having a tapered face 25a opposite to the tapered face 24a is shifted in a direction perpendicular to a mold open/close direction with respect to an upper taper plate 24 to slide between the tapered face 24a and the tapered face 25a, an insert block 22 is shifted in the open/close direction via the lower taper plate 25 to fix the clamp position. In a state that a work W is clamped with a second clamp force C2 larger than a first clamp force C1, a cavity 15a is completely filled with a molten resin 28a at a first resin pressure P1. Subsequently, in a state that the work W is clamped with a third clamp force C3 larger than the second clamp force C2, the molten resin 28a filled in the cavity 15a is pressurized at a second resin pressure P2 larger than the first resin pressure P1.

Description

  The present invention relates to a resin sealing technique, and more particularly to a technique that is effective when applied to a molded product obtained by resin-sealing an electronic component on a substrate.

  Japanese Patent Application Laid-Open No. 6-204379 (Patent Document 1) discloses a method of manufacturing a semiconductor device that uses a mold to cover a semiconductor element and a lead frame with a resin. In this manufacturing method, after the resin injection into the cavity is completed in the mold clamped by applying the first pressure, the pressure is increased to a second pressure higher than the first pressure, and the resin injected into the cavity is applied. Including a step of applying a final molding pressure.

  In Japanese Patent Laid-Open No. 2002-343819 (Patent Document 2), when a semiconductor chip is resin-sealed to a substrate made of a lead frame, a printed circuit board, or the like, the substrate is clamped with an appropriate pressure to be resin-sealed. Technology is disclosed.

JP-A-6-204379 JP 2002-343819 A

  In a resin sealing device by transfer molding, for example, a workpiece having an electronic component mounted on a substrate is clamped by a mold, and the cavity is filled with a molten resin, so that the electronic component is resin-sealed. When molding resin, it is necessary to apply high pressure (molding pressure) to the molten resin filled in the cavity, so the mold must clamp the workpiece with a constant high clamping force so that the resin does not leak. There is.

  However, if the thickness of the substrate varies, when the workpiece is clamped with a certain clamping force, the clamping force acts strongly on the substrate and damages the substrate, or the clamping force acts weakly on the substrate. The resin may leak. In such a case, a defect occurs in the molded product, and the manufacturing yield of the molded product decreases.

  By the way, it is known that when the molten resin starts to be injected into the cavity while the mold is clamping the work, the air in the cavity is compressed and the pressure inside is increased. If the pressure in the cavity is high, the molten resin cannot be filled and the cavity cannot be completely filled. Therefore, an air vent groove is formed on the clamping surface of the mold, and air in the cavity is discharged through the air vent groove when the resin is injected.

  However, when a workpiece is clamped with a mold for a substrate (for example, a resin substrate) covered with an insulating resin layer instead of a metal substrate, such as a lead frame, the clamping force is strong against the substrate. The air vent groove may be blocked by the insulating resin layer. In such a case, the cavity cannot be completely filled with the molten resin, and the production yield of the molded product is reduced.

  From the above, for the first time, the present inventor preferably injected the resin into the cavity with an optimum clamping force in consideration of the air vent in addition to the resin leakage when using a substrate such as a lead frame as well as the resin substrate. I found it.

  The objective of this invention provides the technique which can improve the manufacture yield of a molded article. The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows. In one embodiment of the present invention, a resin sealing method includes (a) a step of separating one and the other molds facing each other and placing a workpiece on the clamping surface of the other mold, and (b) (A) After the step, the one and other molds are brought close to each other, the work is clamped with a first clamping force, and a cavity is formed by the cavity concave portion of the one mold and the work; (C) After the step (b), the first taper plate that is assembled on the opposite side of the clamp surface of the mold block of the other mold and has the first taper surface is opposed to the first taper surface. The second taper plate having the second taper surface is moved in a direction perpendicular to the mold opening / closing direction and slid on the first and second taper surfaces, and the mold block is moved through the first taper plate. Mold opening A step of fixing the clamp position by moving in the direction, and (d) a second clamping force in which the one and the other molds are brought closer to each other after the step (c), and the workpiece is higher than the first clamping force. And a step of injecting molten resin into the cavity by pushing the plunger in a state of being clamped by.

  Of the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows. According to this embodiment, the manufacturing yield of molded products can be improved.

It is sectional drawing which shows typically the principal part of the resin sealing apparatus in operation | movement in one Embodiment of this invention. It is sectional drawing which shows typically the principal part of the resin sealing apparatus in operation | movement following FIG. It is sectional drawing which shows typically the principal part of the resin sealing device in operation | movement following FIG. It is sectional drawing which shows typically the principal part of the resin sealing device in operation | movement following FIG. It is sectional drawing which shows typically the principal part of the resin sealing apparatus in operation | movement following FIG. It is a top view which shows typically the principal part of the workpiece | work of the process target of the resin sealing apparatus shown in FIG. It is a timing chart of clamping force and resin pressure at the time of resin sealing in one embodiment of the present invention. It is sectional drawing which shows typically the principal part of the workpiece | work at the time of the clamp corresponding to FIG. It is sectional drawing which shows typically the principal part of the workpiece | work at the time of the clamp corresponding to FIG. FIG. 8 is a timing chart of clamping force and resin pressure at the time of resin sealing different from the timing chart shown in FIG. 7.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof may be omitted.

  The cross section of the mold 12 which is the principal part of the resin sealing apparatus 11 in this embodiment is shown in FIGS. In FIG. 1 to FIG. 5, one side (right side) of the mold 12 symmetric with respect to the axis of the plunger 27 is shown. 1 to 5 show an operation state until the workpiece W is supplied to the mold 12 and sealed with resin.

  First, the operation of the resin sealing device 11 will be outlined. The resin sealing device 11 supplies the workpiece W (molded product) to the mold 12 with a loader from a molded product supply unit (not shown) (FIG. 1). Next, the workpiece W is clamped with the mold 12 (FIG. 2), and the thickness of the workpiece W is adjusted (FIG. 3). Next, the cavity 15a is injected until the resin is completely filled (FIG. 4), and the resin pressure is increased to the molding pressure to seal the resin (FIG. 5). Next, the workpiece W (molded product) is taken out from the mold mold 12 opened by the unloader and stored in a molded product storage unit (not shown).

  Next, the workpiece | work W used as the process target of the resin sealing apparatus 11 is demonstrated. The workpiece W is an electronic component mounted on a substrate. As shown in FIG. 8, the substrate of the workpiece W is, for example, a wiring pattern 35a, 35b, 32a, 32b (for example, copper or aluminum) via an insulating resin layer 36 (for example, epoxy resin or polyimide resin). The metal substrate is formed in multiple layers, and the surface is protected by an insulating resin layer 33 (for example, a solder resist). The wiring patterns 35a and 35b are formed in the same layer, and the wiring patterns 32a and 32b are formed in the same upper layer.

  Further, as shown in FIG. 1, the electronic component of the workpiece W is, for example, a semiconductor chip 2. The resin substrate 2 (wiring pattern) and the semiconductor chip 2 are electrically connected by bonding wires 3.

  As shown in FIG. 6, a plurality of semiconductor chips 2 (nine in FIG. 6) are mounted on the resin substrate 1 by being arranged in the center and mounted, and a mounting region 4 (first region) to be molded. A peripheral region 5 (second region) surrounding the mounting region 4 at the outer periphery is provided. In this peripheral region 5, a wiring pattern (not shown) is covered with an insulating resin layer (for example, solder resist) (see FIG. 8).

  The cross section of the resin substrate 1 taken along line AA in FIG. 6 is shown correspondingly in FIGS. In FIG. 6, the cavity recess 15, the runner 16, and the air vent groove 18 formed in the mold 12 are also shown in order to clarify the description of FIGS. 1 to 5.

  Next, the configuration of the resin sealing device 11 will be described. As shown in FIG. 1, the resin sealing device 11 includes a mold 12 having an upper mold 13 (mold) and a lower mold 14 (mold) disposed so as to face each other in the vertical direction. The mold 12 is closed when the upper mold 13 and the lower mold 14 are close to each other, and is opened while being spaced apart. When the upper mold 13 is a fixed mold and the lower mold 14 is a movable mold, the lower mold 14 comes close to the upper mold 13 and the mold 12 is closed, and the lower mold 14 is moved relative to the upper mold 13. The mold 12 is opened after being separated. The upper mold 13 may be a movable mold, the lower mold 14 may be a stationary mold, and both may be movable molds.

  The upper die 13 is assembled with a member made of, for example, alloy tool steel. The upper mold 13 is formed with a clamp surface 13a for clamping the workpiece W. The upper mold 13 is formed with a cavity recess 15, a runner 16, and a cull 17 that communicate with each other.

  The cavity recess 15 has a rectangular shape in plan view that is recessed from the clamp surface 13a so as to correspond to the mounting area 4 (FIG. 6) of the resin substrate 1, and encloses the semiconductor chip 2 and the bonding wire 3 at the time of clamping. is there. The runner 16 is a resin path for injecting molten resin into the cavity recess 15, and the resin path is narrowed on the cavity recess 15 side to form a gate. Further, the cull 17 is formed at a position facing the pot 26 in which the resin (for example, the resin tablet 28) is loaded in the lower mold 14.

  The lower mold 14 is assembled with a member made of alloy tool steel, for example. The lower mold 14 is formed with a clamp surface 14a (see FIG. 4) for clamping the workpiece W. The lower mold 14 includes a chase block 21, an insert block 22 (mold block), a clamper block 23, an upper taper plate 24, a lower taper plate 25, and a pot 26. Among these, each of the insert block 22 and the clamper block 23 is formed with clamp surfaces 22a and 23a constituting the clamp surface 14a.

  A recess is formed in the chase block 21, and an insert block 22, a clamper block 23, an upper taper plate 24, and a lower taper plate 25 are assembled therein. A cylindrical pot 26 is provided inside the chase block 21 (left side in FIG. 1). A plunger 27 that can move up and down is inserted into the pot 26, and a resin tablet 28 is supplied so as to be placed at the tip (see FIG. 1).

  The lower taper plate 25 is provided on the bottom surface inside the chase block 21. A taper surface 25 a is formed on the lower taper plate 25 on the side opposite to the inner bottom surface of the chase block 21. Further, as shown in FIG. 1, a gap is formed between the side surface of the lower taper plate 25 and the inner wall surface of the chase block 21 to advance and retreat.

  Such a lower taper plate 25 can be moved back and forth in a direction (left and right direction in FIG. 1) perpendicular to the mold opening and closing direction (up and down direction in FIG. 1) by an advancing and retracting mechanism along the inner bottom surface of the chase block 21. Yes. This advance / retreat mechanism has a configuration in which, for example, the ball screw 29 is rotationally driven by a servo motor 30. The servo motor 30 is provided outside the lower mold 14, and one end of a ball screw 29 is attached to the servo motor 30. The ball screw 29 is inserted into a through hole formed in the chase block 21, and the other end is screwed to the side surface of the lower taper plate 25.

  The upper taper plate 24 is provided on the lower taper plate 25, and the side surface is provided in contact with the inner wall surface of the chase block 21. The upper taper plate 24 is formed with a taper surface 24 a that faces the taper surface 25 a of the lower taper plate 25. The tapered surface 24 a is in contact with the tapered surface 25 a, and the upper tapered plate 24 is provided on the lower tapered plate 25.

  The upper taper plate 24 can move up and down in the mold opening / closing direction along the inner wall surface of the chase block 21 by the lower taper plate 25 moving forward and backward along the inner bottom surface of the chase block 21. .

  The insert block 22 is provided on the upper taper plate 24. The insert block 22 is provided by being inserted into a through hole (guide hole) of the clamper block 23. That is, a clamper block 23 is provided around the side surface of the insert block 22. The thickness of the insert block 22 in the mold opening / closing direction is the same as that of the clamper block 22.

  Such an insert block 22 can be moved up and down in the mold opening / closing direction along the inner wall surface of the clamper block 23 by the upper taper plate 24 moving up and down along the inner wall surface of the chase block 21. The insert block 22 can be moved up and down integrally with the upper taper plate 24 even if it is in contact with the inner wall surface of the clamper block 23 by being fixedly assembled to the upper taper plate 24.

  The clamper block 23 is supported by an elastic member 31 that can expand and contract in the mold opening and closing direction. The elastic member 31 is, for example, a spring, and is assembled such that one end is in contact with the bottom surface inside the chase block 21 and the other end is in contact with the clamper block 23. When the mold 12 is opened (see FIG. 1), the clamp surface 23a of the clamper block 23 has a height from the inner bottom surface of the chase block 21 higher than the clamp surface 22a of the insert block 22 by the elastic member 31. It is high.

  The clamper block 23 has an outer wall surface (side surface) in contact with the inner wall surface of the chase block 21. The clamper block 23 is formed with a through hole (guide hole) penetrating in the thickness direction (mold opening / closing direction), and the insert block 22 is inserted into the through hole. That is, the clamper block 23 has an inner wall surface in contact with the side surface of the insert block 22.

  In such a clamper block 23, the elastic member 31 acts so as to resist the clamping force for clamping the workpiece W by the upper die 13 and the lower die 14, and the elastic member 31 expands and contracts, so that It can be moved up and down in the mold opening / closing direction along the wall surface and the side surface of the chase block 21. 1 to 5, the elastic member 31 is illustrated so as to overlap with the upper taper plate 24 and the lower taper plate 25, but actually, the elastic member 31 is inserted into the through holes formed in these.

  Next, a resin sealing method for the workpiece W in the present embodiment, that is, an operation method of the resin sealing device 11 will be described with reference to FIGS. 1 to 5 and FIGS. 7 to 9. 1 to 5 are cross-sectional views schematically showing the main part of the resin sealing device 11 in operation, and FIG. 7 is a timing chart of clamping force and resin pressure during resin sealing. 8 and 9 are cross-sectional views schematically showing main parts of the workpiece W corresponding to FIGS. 4 and 5, respectively.

  As shown in FIG. 1, the upper mold 13 (one mold) and the lower mold 14 (the other mold) facing each other are separated, that is, the mold mold 12 is opened, and the clamp surface of the lower mold 14 is opened. The work W is placed on. In the present embodiment, the work W is placed with the insert block 22 corresponding to the mounting area 4 (see FIG. 6) of the wiring board 1 and the clamper block 23 corresponding to the surrounding area 5.

  In a state where the mold 12 is opened, the clamp surface 22 a of the insert block 22 is retracted from the clamp surface 23 a of the clamper block 23. In other words, the clamp surface 23 a of the clamper block 23 is higher in height from the inner bottom surface of the chase block 21 than the clamp surface 22 a of the insert block 22. For this reason, in the state where the mold 12 is opened, the workpiece W is the clamp surface 22a of the insert block 22 and the clamp surface 23a of the clamper block 23 that constitute the clamp surface 14a (see FIG. 4) of the lower mold 14. The clamper block 23 is placed on the clamp surface 23a.

  Here, in the state where the mold 12 is opened, the insert block 22 is adjusted to the most retracted position. Specifically, the lower taper plate 25 is most retracted in the direction orthogonal to the mold opening / closing direction with respect to the upper taper plate 24 on which the insert block 22 is provided. Thus, since the insert block 22 is in the most retracted position, the workpiece W can be reliably placed on the clamp surface 23a of the clamper block 23 of the mold 12 that has been opened. In addition, as a preparation for adjusting the thickness variation (plate thickness adjustment) of the wiring board 1 (work W) in the subsequent process, the insert block 22 is adjusted to the most retracted position.

  Subsequently, as shown in FIG. 2, the upper die 13 and the lower die 14 are brought close to each other (the die is closed), and the workpiece W is clamped with the first clamping force C <b> 1 (see FIG. 7). A cavity 15 a is formed by the cavity recess 15 and the workpiece W.

  Here, at time t1 in FIG. 7, the clamp surface 13a of the upper mold 13 and the peripheral region 5 (see FIG. 6) of the wiring board 1 come into contact with each other, and the elastic member 31 starts to shrink due to the application of the clamping force. When the mold closing of the mold 13 and the lower mold 14 is completed (at time t2 in FIG. 7), in other words, when the plate thickness adjustment is completed, the elastic member 31 stops when the first clamping force C1 is reached. To do. The elastic member 31 presses the clamper block 23 against the first clamping force C1. That is, even if the thickness of the wiring board 1 (work W) varies, the work W is clamped (plate thickness adjustment) with a predetermined first clamping force C1.

  In the present embodiment, the workpiece W is clamped by the clamper block 23 in a state where the elastic member 31 is contracted against the first clamping force C1. Therefore, since it is the structure clamped with respect to the surrounding area | region 5 of the wiring board 1, the situation where the clamping force of this area | region raises too much and a circuit is fractured | ruptured and a board | substrate can be prevented reliably.

  In FIG. 2, the clamp surface 22 a of the insert block 22 and the clamp surface 23 a of the clamper block 23 are shown to be in the same horizontal plane, but in reality, the insert block 22 is slightly retracted from the clamper block 23. ing.

  Subsequently, as shown in FIG. 3, with respect to the upper taper plate 24 assembled on the side opposite to the clamp surface 22 a of the insert block 22, the lower taper plate 25 is pulled out from the lower mold 14 in a direction orthogonal to the mold opening / closing direction. Push (move) in the right direction and slide on the taper surface 24a and taper surface 25a, and move the insert block 22 in the mold opening / closing direction (upward) via the upper taper plate 24 to set the clamp position. Fix it.

  The workpiece W is clamped with the first clamping force C1 from the completion of the plate thickness adjustment (at the time t2 in FIG. 7) until the clamping force starts to increase (at the time t3). That is, as shown in FIG. 7, the lower taper plate 25 starts to move at time t2, and the lower taper plate 25 is inserted between the upper taper plate 24 and the inner bottom surface of the chase block 21 at time t3.

  Here, the workpiece W is clamped by the upper mold 13 and the clamper block 23, in other words, the clamper block 23 is fixed to the upper mold 13 by the elastic member 31. Further, the insert block 22 and the clamper block 23 have the same thickness, and the insert block 22 is retracted from the clamper block 23 in the state described with reference to FIG. Therefore, the lower taper plate 25 is moved by this retracted amount, and the insert block 22 is moved via the upper taper plate 24. That is, the clamp surface 22a of the insert block 22 and the clamp surface 23a of the clamper block 23 are flush with each other to form the clamp surface 14a, and the position is fixed as the clamp position.

  Next, as shown in FIG. 7, the clamping force of the workpiece W starts to increase so as to become stronger than the first clamping force C1 at time t3, so that the second clamping force C2 is reached (time t4). The second clamping force C2 is generated by bringing the upper die 13 and the lower die 14 closer from the state of the first clamping force C1.

  Subsequently, as shown in FIG. 4, in the state where the workpiece W is clamped with the second clamping force C2 higher than the first clamping force C1, the plunger 27 is pushed to melt the cavity 15a until it is completely filled. 15a (molten resin tablet 15) is injected.

  In a state in which the workpiece W is clamped with the second clamping force C2 (from time t4 to time t7 in FIG. 7), the plunger 27 rises and injection of the molten resin 15a is started (time t5 in the same figure), and the resin pressure increases. When the molten resin 15a is filled, the first resin pressure P1 is applied to the cavity 15a (time t6 in the figure). That is, the resin filling into the cavity 15a is completed by the time t6.

  Further, in the time period from the time t4 to the time t7, as shown in FIG. 8, the clamp surface 13a of the upper mold 13 is pressed against the peripheral area 5 of the wiring board 1 (work W) so as to be between the wiring patterns 32a and 32b. An air path 34 is formed by unevenness of the insulating resin layer 33 (for example, solder resist). In the present embodiment, the molten resin 28a is injected into the cavity 15a while air venting through the air passage 34.

  As a result, the air in the cavity 15a is discharged through the air passage 34 in addition to the air vent groove 18 (see FIG. 6) when the resin is injected, so that the cavity 15a is completely filled with the molten resin 28a more reliably. can do. Therefore, the production yield of the molded product can be further improved. Further, since the clamping force C2 is applied after the plate thickness is adjusted and the insert block 22 is fixed by the upper and lower taper plates 24, 25, even if the thickness of the resin substrate 1 varies, all the wiring substrates 1 are clamped with a uniform clamping force. Therefore, air can be reliably discharged without causing resin leakage. Further, when the workpieces W are arranged on both sides of the pot 26 and are collectively sealed with resin, even if the thicknesses of the pair of substrates to be sealed simultaneously are different, it is possible to clamp with a uniform clamping force. Therefore, it is preferable.

  Next, as shown in FIG. 7, the clamping force of the workpiece W is increased so as to be stronger than the second clamping force C2 at time t7 so as to become the third clamping force C3 (time t8). The third clamping force C3 is generated by bringing the upper die 13 and the lower die 14 closer from the state of the first clamping force C2.

  Subsequently, as shown in FIG. 5, in a state where the workpiece W is clamped with the third clamping force C3 higher than the second clamping force C2, the plunger 27 is further pushed to the molten resin 28a filled with the cavity 15a. In contrast, the second resin pressure P2 (molding pressure) higher than the first resin pressure P1 is applied.

  As shown in FIG. 7, the workpiece W remains clamped with the third clamping force C3 from time t8. At this time, after the third clamping force C3 is applied, the plunger 27 further rises and starts to pressurize the molten resin 15a filled in the cavity 15a (time t9), and the plunger 27 is raised to a predetermined position. At the time (time t10), the second resin pressure P2 is applied to the cavity 15a. That is, after time t10, the second resin pressure P2 (molding pressure) is applied to the molten resin 15a filled in the cavity 15a. The second resin pressure P2 is applied for a predetermined time from time t10 to heat and cure the molten resin 28a, and then the mold 12 is opened and the workpiece W (molded product) is taken out.

  Further, in the time zone after the time t8, as shown in FIG. 9, the clamp surface 13a of the upper mold 13 is pressed against the peripheral region 5 of the wiring board 1 (work W) with the third clamping force C3, thereby FIG. The air passage 34 shown in FIG. Thereby, even when the second resin pressure P2 is applied to the molten resin 28a in the cavity 15a, the resin leakage in the peripheral region 5 can be prevented. Therefore, the production yield of the molded product can be further improved.

  Although the present invention has been specifically described above based on the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.

  For example, in the above-described embodiment, the case where it is applied to a resin substrate as a substrate constituting the workpiece has been described. However, the present invention is not limited to this, and the present invention can also be applied to a semiconductor wafer, a ceramic substrate, a lead frame, or the like whose surface is covered with a film (for example, a protective film or a plating film). Moreover, the case where it applied to the electronic component as a member sealed with resin with a workpiece | work was demonstrated. The present invention is not limited to this, and can also be applied to components that are protected by resin sealing. For example, as an electronic component, it can be applied to a capacitor of a chip-shaped component.

  In the above embodiment, the case where the insert block 22 and the clamper block 23 are provided separately and the clamper block 23 is supported by the elastic member 31 has been described. The present invention is not limited to this, and the present invention can also be applied to a case where the insert block 22 and the clamper block 23 are formed as an integral mold block and supported by the elastic member 31.

  In the above embodiment, the case where the molten resin 28a is injected into the cavity 15a while the air passage 34 (see FIG. 8) is formed and the air in the cavity 15a is discharged has been described. Not limited to this, if the air path is secured in the air vent groove 18 (see FIG. 6), the air in the cavity 15a can be discharged when the molten resin 28a is injected. It does not have to be formed. However, as shown in the embodiment, when the air passage 34 is formed in addition to the air vent groove 18, the discharge effect can be expected more.

  Moreover, although the said embodiment demonstrated the case where the process of adjusting plate | board thickness was included, it is effective also when not including the process of plate | board thickness adjustment. For example, first, the upper mold 13 and the lower mold 14 facing each other are separated from each other, and the workpiece W is placed on the clamp surface of the lower mold 14. Next, the upper die 13 and the lower die 14 are brought close to each other to clamp the workpiece W with a low clamping force (corresponding to the first clamping force C1), and the cavity 15a is formed by the cavity concave portion 15 of the upper die 13 and the workpiece W. The molten resin 28a is injected at the first resin pressure P1 until the cavity 15a is completely filled. Next, in a state where the workpiece W is clamped with a high clamping force (corresponding to the third clamping force C3) higher than the low clamping force, the second higher than the first resin pressure P1 with respect to the molten resin 28a filled in the cavity 15a. Pressurize with resin pressure P2. Since the work W is clamped with a low clamping force when the cavity 15a is completely filled in this way, air in the cavity 15a is supplied to the air passage 34 in addition to the air vent groove 18 (see FIG. 6) during resin injection. But it can be discharged. Thereby, the inside of the cavity 15a can be reliably filled with the molten resin 28a. Therefore, the production yield of the molded product can be further improved.

  In the above embodiment, the case where the cavity 15a is completely filled with the molten resin 28a with the first resin pressure P1 that is weaker than the final second resin pressure P2 has been described with reference to FIG. That is, a case has been described in which resin molding is performed with a two-stage resin pressure while maintaining each of the first resin pressure P1 (filling pressure) and the second resin pressure P2 (final molding pressure) for a predetermined time. Not limited to this, as shown in FIG. 10, the second resin pressure P2 is also effective when resin molding is performed with a single-stage resin pressure maintained for a predetermined time. For example, first, the workpiece W is placed on the clamp surface of the lower mold 14. Next, the upper die 13 and the lower die 14 are brought close to each other, the workpiece W is clamped with a low clamping force (corresponding to the first clamping force C1) by the plate thickness adjusting mechanism, and then clamped with the second clamping force. At this time, the plunger 27 is raised (pushed) to start injection of the molten resin 28a. Next, in a stage sufficiently before the filling of the molten resin 28a is completed, after clamping with a high clamping force (corresponding to the third clamping force C3), the filling of the molten resin 28a is completed. Next, the plunger 27 is further raised (pushed), and the molten resin 28a filled in the cavity 15a is pressurized with a resin pressure (final molding pressure) corresponding to the second resin pressure P2. Since the workpiece W is clamped with a low clamping force (corresponding to the second clamping force C2) just before the cavity 15a is completely filled, the air vent groove 18 (see FIG. 6), and the air passage 34 can also be discharged. Thereby, the inside of the cavity 15a can be reliably filled with the molten resin 28a. Therefore, the production yield of the molded product can be further improved.

13 Upper mold 13a Clamp surface 14 Lower mold 14a Clamp surface 15 Cavity recess 15a Cavity 22 Insert block (mold block)
24 Upper taper plate 24a Tapered surface 25 Lower taper plate 25a Tapered surface 27 Plunger 28a Molten resin W Workpiece

Claims (5)

(A) separating the opposing one and other molds and placing a workpiece on the clamping surface of the other mold;
(B) After the step (a), the one and the other molds are brought close to each other to clamp the workpiece with a first clamping force, and a cavity is formed by the cavity concave portion of the one mold and the workpiece. And a process of
(C) After the step (b), the first taper plate that is assembled on the opposite side of the clamp surface of the mold block of the other mold and has the first taper surface is opposed to the first taper surface. The second taper plate having the second taper surface is moved in a direction perpendicular to the mold opening / closing direction and slid on the first and second taper surfaces, and the mold block is moved through the first taper plate. Moving in the mold opening and closing direction to fix the clamp position;
(D) After the step (c), the one and the other molds are brought closer together, and the plunger is pushed in a state where the workpiece is clamped with a second clamping force higher than the first clamping force. Injecting molten resin into the cavity;
A resin sealing method comprising: The resin sealing method according to claim 1,
In the step (d), molten resin is injected at a first resin pressure until the cavity is completely filled,
(E) After the step (d), the one and the other molds are brought closer together, and the plunger is further pushed in a state where the workpiece is clamped with a third clamping force higher than the second clamping force. And pressurizing the molten resin filled in the cavity with a second resin pressure higher than the first resin pressure. The resin sealing method according to claim 1,
(E) After the step (d), the one and the other molds are brought closer together, and the plunger is further pushed in a state where the workpiece is clamped with a third clamping force higher than the second clamping force. And a step of pressurizing the molten resin filled in the cavity with a molding pressure. In the resin sealing method of Claim 1, 2, or 3,
The other mold is supported by an elastic member that can expand and contract in the mold opening and closing direction, and has a clamper block that surrounds the mold block,
In the step (b), the resin sealing method is characterized in that the workpiece is clamped by the clamper block in a state where the elastic member is contracted against the first clamping force. In the resin sealing method of Claim 4,
The workpiece is a substrate in which a first region and a second region surrounding the first region are provided, electronic parts are mounted in the first region, and a wiring pattern is covered with an insulating resin layer in the second region. Yes,
In the step (a), the mold block is made to correspond to the first area, the workpiece is placed with the clamper block made to correspond to the second area,
In the step (d), the clamp surface of the one mold is pressed against the second region and melted into the cavity while air venting in an air path formed by the unevenness of the insulating resin layer between the wiring patterns. A resin sealing method characterized by injecting a resin.

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