JP2010058472A - Method for sealing and molding laminated body and mold for molding used for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly precise method for sealing and molding by which peeling-off and positional shift are not generated when a resin is injected. <P>SOLUTION: The method for sealing and molding a laminated body 11 is a molding method in which a substrate 15 and the laminated body 11 prepared by laminating a plurality of sheets of metal foils 12 which are held on one face of this substrate 15 and form capacitor elements 13 each with a tongue piece shape whose one end is the free end and other end is the fixed end, are hung on a bottomed recessed part 19 provided in a mold for molding, and a molten resin 21 is poured into this recessed part 19 to impregnate the resin into the laminated body 11 and to seal and mold it. The impregnation is gradually performed from the main face of the laminated body 11 so that the impregnation becomes approximately in parallel to the surface of the resin 21 poured into the recessed part 19, and after the resin 21 is pressed for a definite time, the resin is cured. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a sealing molding method for sealing and molding an electronic component such as a laminate with a resin and a molding die used therefor.

  In order to manufacture electronic parts in a small size and at low cost, a so-called wafer process is used in which a plurality of parts are simultaneously formed on a large-area substrate and then cut and separated into pieces.

  FIG. 8 shows an example of a manufacturing method of an MCM (Multi chip module) in which a plurality of semiconductors 1 are mounted in one package. The lower mold 2 and the upper mold 4 having a recess 3 serving as a cavity on the lower surface sandwich the peripheral portion of the substrate 5 on which the semiconductor 1 is mounted on one surface. Among the four sides of the upper mold 4, a plurality of gates 6 communicating with the recess 3 are provided on the lower end surface 4 a of one side, while a plurality of gates are provided on the lower end surface 4 b of the opposite side facing the one side provided with the gate 6. A main air vent 7 is provided. And the sub air vent 8 connected to the recessed part 3 and the main air vent 7 is provided in the inner edge part of the lower end surface 4b of the opposing side facing the one side which provided the gate 6 along the said opposing side. Therefore, the resin 10 supplied from the plunger 9 spreads substantially horizontally with respect to the substrate 5 through the gate 6, and the air in the recess 3 is discharged through the sub air vent 8 and the main air vent 7, The surface of the substrate 5 is encapsulated with the resin 10 without leaving or mixing bubbles. Finally, the substrate 5 is released from the mold and cut into individual pieces.

As prior art document information relating to this application, for example, Patent Document 1 is known.
JP 2006-269786 A

  In the above method, the resin 10 melted by the plunger 9 is supplied from the horizontal direction of the substrate 5 through the gate 6. Therefore, when used for resin sealing of a laminate in which green sheets, metal foils, etc. are laminated, the resin 10 supplied from the horizontal direction enters between the layers, causing peeling and misalignment. There has been a problem of lowering.

  Then, this invention aims at improving the precision of sealing molding.

  In order to achieve this object, the present invention is a method for sealing and forming a laminate, which is held on one surface of the substrate, and has a tongue-shaped element having one end as a free end and the other end as a fixed end. After suspending a laminated body formed by laminating a plurality of metal foils formed with a bottomed recessed portion provided in a molding die, the molten resin is poured into the recessed portion to be immersed in the laminated body. A molding method for sealing molding, wherein the immersion is performed by gradually immersing from the main surface of the laminate so as to be substantially parallel to the surface of the resin injected into the recess, and pressurizing the resin for a certain period of time. It is to be cured.

  In the sealing molding method of the laminate according to the present invention, when the laminate in which the metal foil in which a plurality of elements are formed is laminated is molded with resin, the main surface of the laminate with respect to the surface of the molten resin, That is, the surface on which the element is formed is gradually immersed in a resin while being kept substantially parallel, pressed for a certain time, and then cured. Therefore, since only the pressure from the substantially vertical direction is applied to the main surface of the laminate when immersed in the resin, the immersed resin does not enter between the layers of the metal foil forming the element, and as a result, peeling There is an effect that sealing molding can be performed with high accuracy without any misalignment or misalignment.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view for explaining an example of a laminate that is a molded article using the sealing molding method of the present invention. In order to make the explanation easy to understand, the uppermost layer is shown separated upward.

  The laminated body 11 of the present embodiment is an intermediate for producing a solid electrolytic capacitor, and one end is formed by performing a substantially H-shaped through process 14 on a metal foil 12 such as aluminum having a valve action. A large number of tongue-shaped capacitor elements 13 having a free end and the other end as a fixed end are formed. Although the drawing is simplified, the capacitor elements 13 are formed on one surface of the metal foil 12.

  A multilayer body 11 is formed by applying a conductive paste in which silver or copper is dispersed on the capacitor element 13 and laminating a plurality of sheets, and electrically connecting the condenser elements 13. By laminating in this way, the capacitor elements 13 are connected in parallel to obtain a certain capacity.

  The capacitor element 13 is formed by forming a dielectric oxide film layer by roughening the surface of the metal foil 12 as a base material by etching or the like, and then forming a solid electrolyte layer made of a conductive polymer, a conductor layer made of carbon or the like. These are formed in order, and the surface is used as a cathode. Prior to the formation of the cathode, the capacitor element 13 is separated from the cathode by coating a part of the dielectric oxide film layer with an insulating resist or the like to form an anode.

  The metal foil 12 on which the capacitor element 13 is formed is laminated to form a laminate 11, and the periphery of the laminate 11 including the capacitor element 13 is sealed with a resin, and then each capacitor element 13 is individually separated by dicing or the like. Tidy up. And after exposing the cross section of each capacitor | condenser element 13 containing the electrically conductive paste which laminates | stacks each capacitor | condenser element 13 from one side of the piece, and forms the cathode, and from the other side contains the insulating resist used as an anode, Plating, conductive resin paste, etc. are applied and taken out as external terminals serving as a cathode and an anode, respectively.

  The laminated body 11 is temporarily fixed on a substrate 15 such as a resin using an adhesive or the like, and then the periphery including the laminated capacitor elements 13 is sealed with an insulating resin to form an exterior body. . Next, an embodiment of a molding die used for this sealing molding will be described.

  FIG. 2 is a cross-sectional view for explaining an embodiment of a molding die used in the sealing molding method of the present invention. The molding die is opened, and the laminate is conveyed and placed.

  The molding die according to the present embodiment has a heating mechanism and is configured by combining two molds of a fixed mold 16 and a movable mold 17. The top surface 16a of the fixed die 16 is a separation surface, and the movable die 17 is movable up and down along a positioning pin 18 through which the fixed die 16 and the movable die 17 are inserted.

  A bottomed recess 19 for mounting and fixing the laminated body 11 is provided on the top surface 16 a of the fixed mold 16. The laminated body 11 temporarily fixed to the substrate 15 is placed in the concave portion 19 with the laminated body 11 facing downward, and supports both sides, that is, the two sides on the front and back of the paper surface. Suspended by.

  Further, a pot 20 is provided adjacent to the recess 19, and the pellet-shaped resin 21 is clamped and melted in the pot 20, and then the plunger 22 is raised and pressurized to press the recess 19. To be supplied and injected.

  Further, the recess 19 is provided with a protruding pin 23 that can be moved up and down through the fixed mold 16. After the resin is heat-cured and cooled to a certain temperature, the protruding pin 23 is raised. Thus, the molded product is extruded from the fixed mold 16 and released.

  The fixed mold 16 described above is elastically supported on the base 25 by an urging mechanism 24 including a spacer block 24a, a shoulder bolt 24b, a spring 24c, and the like, and the movable mold 17 is brought into contact with the fixed mold 16. Thereafter, both the movable mold 17 and the fixed mold 16 can be lowered by further lowering the movable mold 17. A compression plunger 26 is disposed on the bottom surface of the recess 19. The compression plunger 26 has a lower end fixed to the base 25 and an upper end slidably inserted into the fixed mold 16. . Therefore, when the fixed die 16 is lowered or raised by the urging mechanism 24, the top surface of the compression plunger 26 is raised or lowered relative to the fixed die 16, and as a result, the depth of the concave portion 19 is increased. Will fluctuate.

  When the fixed mold 16 is in an unloaded state, that is, when the mold is opened, the fixed mold 16 is biased to the uppermost position by the biasing mechanism 24 and the compression plunger 26 is positioned at the bottom dead center with respect to the fixed mold 16. It is in. At the bottom dead center, the top surface of the compression plunger 26 is adjusted so as not to contact the bottom surface of the laminated body 11 and to be at a lower position by a certain amount. A certain amount of molten resin 21 is stored in the gap between the bottom surface of the laminate 11.

  What is important at this time is the resin supply path from the pot 20. In this embodiment, the spigot block 27 is provided on the bottom surface of the movable mold 17, and when the fixed mold 16 and the movable mold 17 are clamped, the spigot block 27 and the bottom surface of the recess 19 have a fixed gap, that is, A gate 28 serving as a supply port for the resin 21 is formed. The resin 21 melted in the pot 20 is supplied and injected into the recess 19 through a runner (not shown) and a gate 28. The position of the gate 28 is arranged on the side of the bottom dead center of the compression plunger 26, that is, the lower end of the gate 28 is not less than the bottom dead center and the upper end is less than the bottom surface of the laminate 11. By arranging in this way, when the resin 21 is supplied to the recess 19, a certain amount can be stored by gradually filling the resin 21 from the bottom surface of the recess 19 without contacting the laminate 11. As a result, the resin 21 does not enter between the layers of the stacked body 11, and it is possible to prevent the separation and misalignment between the layers.

  After the resin 21 is once stored in the recess 19 in this way, the movable die 17 is further lowered to push down the fixed die 16. In this way, the compression plunger 26 is relatively raised, the resin 21 is brought into contact with the laminated body 11 substantially horizontally, and then the resin 21 is immersed at a constant pressure for sealing molding.

  Note that the movable die 17 is provided with a pressure adjusting pin 29, and the resin 21 in the recess 19 is controlled to have a constant pressure by flowing in excess resin 21 when immersed.

  Next, an example of the sealing molding method using this molding die will be described in order using the sectional view of the molding die.

  First, as shown in FIG. 3, the laminated body 11 temporarily fixed on the substrate 15 is placed in the concave portion 19 with the laminated body 11 as the lower surface side, and the pellet-shaped resin 21 to be sealed is supplied to the pot 20. To do. At this time, the laminate 11 is suspended on the recess 19 while supporting two sides (two sides on the back and front of the paper). Further, the compression plunger 26 is at the bottom dead center position with respect to the fixed mold 16, does not contact the bottom surface of the stacked body 11, and is in a lower position. Therefore, a certain amount of gap is provided between the bottom surface of the stacked body 11 and the top surface of the compression plunger 26.

  Next, as shown in FIG. 4, the movable mold 17 is lowered and lightly brought into contact with the fixed mold 16 to sandwich the two sides of the laminated body 11 and temporarily stop. Then, the resin 21 melted in the pot 20 is supplied and injected into the recess 19 through the gate 28 and filled so as not to contact the bottom surface of the laminate 11. What is important at this time is the position and size of the gate 28. In other words, the lower end of the gate 28 is provided on a side slightly higher than the bottom dead center of the compression plunger 26, and the diameter thereof is set so that the upper end side is less than the bottom surface of the laminate 11. By doing so, the molten resin 21 is injected from the bottom surface of the recess 19 without being brought into contact with the laminated body 11 in the vicinity of the gate 28 and gradually filled. As a result, the resin 21 does not enter between the layers, and peeling or misalignment does not occur. Further, even when excessive resin 21 is supplied to the recess 19 and reaches the bottom surface of the laminated body 11 due to variations in the supply amount, the resin 21 comes into contact with the bottom surface of the laminated body 11 almost horizontally, Misalignment does not occur.

  The reason why the lower end of the gate 28 is slightly higher than the bottom dead center of the compression plunger 26 is that the compression plunger 26 is slightly raised when the laminate 11 is sandwiched. The position of the lower end of the gate 28 is appropriately adjusted in accordance with the pressure for sandwiching the stacked body 11, that is, the pressing force by the movable die 17.

  Next, as shown in FIG. 5, the movable die 17 is lowered again, and the fixed die 16 is lowered together via the biasing mechanism 24. By the lowering of the fixed mold 16, the compression plunger 26 rises relative to the fixed mold 16, and the molten resin 21 stored in the concave portion 19 is brought into contact with the laminated body 11 and is gradually immersed. What is important at this time is the immersion of the resin 21 in the laminate 11 and the flow of the resin 21 at that time. By raising the compression plunger 26, the surface of the resin 21 stored in the concave portion 19 comes into contact with the bottom surface of the laminate 11 in a substantially parallel state. Therefore, since the resin 21 is pressurized and immersed in the laminated body 11 almost vertically, the resin 21 does not penetrate between the layers of the laminated body 11, and as a result, the separation or misalignment between the layers is prevented. It is possible to perform high-precision sealing molding that does not occur.

  In this way, the periphery of the laminate 11 is sealed with the resin 21, and the movable die 17 is further lowered to compress and compress the resin 21. By doing so, the resin 21 can be reliably filled into a narrow gap such as the substantially H-shaped through portion (14 portion in FIG. 1) of the present embodiment. In addition, at the time of pressurization and compression, the excess resin 21 is caused to flow into the pot 20 or the pressure adjusting pin 29 so that the pressure is controlled at a constant pressure so that the resin 21 in the recess 19 does not become excessive pressure. By carrying out like this, it can seal-mold with high precision, without applying excessive load to the laminated body 11. FIG.

  Next, as shown in FIG. 6, the resin 21 is heated and cured for both the fixed mold 16 and the movable mold 17 and cooled to a predetermined temperature or lower, and then the movable mold 17 is raised to relatively lower the compression plunger 26. Let the mold release. By doing so, the compression plunger 26 is surely released from the bottom surface of the molded article 29, and the movable mold 17 is further raised to open the mold, and then the push pin 23 is raised to remove the molded article 29. By pushing up, the molded product 29 shown in FIG. 7 is released from the fixed mold 16 and taken out.

  In FIG. 7, 29a, 29b, 29c, and 29d are portions where the resin 21 remaining in the supply path from the pot 20 to the recess 19 is solidified. 29a is the pot 20, 29b is a runner, and 29c is an inlay block. 27 and 29 d correspond to the gate 28. In the sealing molding method described above, the supply path from the pot 20 to the recess 19 has been described as a straight line for easy understanding. However, as shown in FIG. 7, the gate 28 and the inlay block 27 are sandwiched between the pot 20. It may be arranged. By doing so, the mold can be reduced in size, and the resin 21 can be supplied from the single pot 20 to the plurality of gates 28 and supplied to the recesses 19. However, it can be stably and surely sealed without bubbles and the like being mixed.

  By using the above molding die and sealing molding method, a laminate such as a solid electrolytic capacitor can be sealed and molded without causing delamination or misalignment between layers, and formed into a laminate. It is possible to reliably fill and seal the resin in the narrow gap. As a result, the laminate can be molded with high accuracy.

  In the above description, the solid electrolytic capacitor has been described as an example of a laminated body, but the present invention can also be applied to other electronic components that seal-mold the laminated body using a wafer process.

  In the sealing molding method of the laminate according to the present invention, when the laminate in which the metal foil in which a plurality of elements are formed is laminated is molded with resin, the main surface of the laminate with respect to the surface of the molten resin, That is, the surface on which the element is formed is gradually immersed in a resin while being kept substantially parallel, pressed for a certain time, and then cured. Therefore, since only the pressure from the substantially vertical direction is applied to the main surface of the laminate when immersed in the resin, the immersed resin does not enter between the layers of the metal foil forming the element, and as a result, peeling The sealing molding method for molding an electronic component such as a laminate with a resin and the molding die used for the same are achieved. Useful.

The perspective view explaining an example of the laminated body using the sealing molding method of this invention Sectional drawing explaining an example of the metal mold | die for molding of this invention Sectional drawing of the metal mold | die explaining the sealing molding method of this invention Sectional drawing of the metal mold | die explaining the sealing molding method of this invention Sectional drawing of the metal mold | die explaining the sealing molding method of this invention Sectional drawing of the metal mold | die explaining the sealing molding method of this invention The perspective view explaining an example of the molded article using the sealing molding method of this invention Cross-sectional view of relevant parts for explaining a conventional molding die

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Laminated body 12 Metal foil 13 Capacitor element 15 Board | substrate 16 Fixed type 17 Moving type 19 Recessed part 22 Plunger 26 Compression plunger 28 Gate

Claims (3)

A molding die is provided with a substrate and a laminate formed by laminating a plurality of metal foils that are held on one surface of the substrate and have one end as a free end and the other end as a fixed end to form a tongue-shaped element. It is a molding method in which after being suspended on a bottomed recess, the molten resin is injected into the recess so as to be immersed in the laminate and sealed, and the immersion is the surface of the resin injected into the recess The laminate is molded by immersing gradually from the main surface of the laminate so as to be substantially parallel to the substrate, pressurizing the resin for a certain time, and then curing the laminate. While having a bottomed recess for placing the laminate on the top surface, a fixed mold provided with a plunger for supplying molten resin to the recess, and a movable mold disposed facing the recess, A molding die that can be freely moved up and down with the top surface as a separation surface, and a compression plunger that is vertically inserted is provided on the bottom surface of the recess, and the compression plunger is stacked at the bottom dead center position. After a certain amount of molten resin is stored in the gap with the body, the resin is brought into contact with the main surface of the laminated body by being raised and gradually immersed so as to be heated and cured by pressing for a certain time. Mold for molding. The molding die according to claim 2, wherein a gate for supplying molten resin from the plunger portion to the concave portion is provided on the side of the bottom dead center of the compression plunger.

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