JP2015030235A - Resin sealing mold, resin sealing method, and method for cleaning resin sealing mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin sealing mold which can ensure workpiece adsorption.SOLUTION: An upper mold 11 includes cavity recesses 14 in which a sealing resin R is filled at the time of resin sealing. A lower mold 12 includes an insert 15 which is provided with a plurality of adsorption grooves 16 opening in a mold clamp surface on which a workpiece W is arranged, and a plurality of blocks 17 in the groove which are respectively provided in the plurality of adsorption grooves 16. A suction passage 21 sucking the workpiece W is formed in a clearance 22 between an inner wall surface of the adsorption groove 16 and an outer wall surface of the block 17 in the groove. A tip of the block 17 in the groove facing the mold clamping surface from the adsorption groove 16 is chamfered in a tapered shape.

Description

  The present invention relates to a resin-sealed mold, and in particular, a resin-sealed mold that includes one and the other molds, clamps a workpiece with the one and the other molds, and performs resin sealing, and uses the same. The present invention relates to a resin sealing method and a technique effective when applied to the cleaning method.

  When a workpiece is placed in the resin-sealed mold, the workpiece heated at the mold temperature is greatly warped until reaching a certain temperature. In order to alleviate this, it is a common practice to provide a suction mechanism in the resin-sealed mold to hold the lead frame by suction.

  Japanese Patent Application Laid-Open No. 2006-88692 (Patent Document 1) discloses a resin seal in which a circular hole for sucking (sucking) a workpiece (molded product) is provided on an end surface of a clamp block in which a movable block is provided in a sliding hole. A stop mold is described. Also, instead of providing a circular hole in the clamp block, a clearance is provided between the inner surface (inner wall surface) of the sliding hole and the side surface (outer wall surface) of the movable block, and this clearance is communicated with the air suction mechanism. And sucking the workpiece (see paragraph [0018] of the specification in particular).

JP 2006-88692 A

  For example, in a product such as a MAP (Molded Array Packaging) type QFN (Quad For Non-Lead Package), one side of a lead frame is sealed with resin. In order to prevent resin leakage on the back surface side of the lead frame during the resin sealing, a tape (for example, polyimide tape) is attached to the back surface of the lead frame, and the resin sealing is performed.

  Using a resin-sealed mold in which a gap is provided between the inner wall surface of the sliding hole of the insert block (clamp block) and the outer wall surface of the cavity block (movable block) as described in Patent Document 1 When the resin sealing is performed on the lead frame to which the tape is attached, the tape may be pushed into the gap by the resin pressure during the resin sealing. In particular, the structure that sucks and holds the workpiece on the mold clamping surface through the gap between the outer wall surface of the cavity block having the same size as the molding area and the inner wall surface of the sliding hole of the insert block is based on the suction operation and the resin pressure. The tape is easily pushed into the gap.

  That is, the tape is easily peeled off from the lead frame, and the sealing resin leaks to the back surface of the lead frame, resulting in bleed. In addition, when bleed occurs, it is necessary to remove it, and productivity is lowered. Therefore, it is conceivable to use a resin-sealed mold in which small circular holes are provided around the molding region as described in Patent Document 1. However, in the structure in which small circular holes are provided and held by suction, the suction capacity may be insufficient.

  By the way, when the mold clamping surface of a resin-sealed mold provided with a small circular hole is cleaned using a cleaning sheet (cleaning resin), the cleaning sheet that is closed and thinly stretched partially enters the circular hole. Therefore, even if it is attempted to remove the cleaning sheet, the portion that has entered the circular hole may be separated from the cleaning sheet main body and remain as it is. In this case, it becomes difficult to suck the workpiece onto the mold clamping surface in the subsequent steps. Further, when the cleaning sheet partially remains, it is necessary to remove it, and maintenance performance (workability) is deteriorated. This problem is not limited to the structure in which the work is sucked and held, but is provided with a gap between the inner wall surface of the sliding hole of the insert block and the outer wall surface of the cavity block. Also occurs.

  The objective of this invention is providing the resin sealing metal mold | die which can ensure workpiece | work adsorption | suction. Another object of the present invention is to provide a resin-sealed mold capable of preventing the cleaning sheet remaining on the mold clamping surface. Another object of the present invention is to provide a resin-sealed mold that can prevent resin leakage. 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.

  The resin-sealed mold in one embodiment of the present invention is a resin-sealed mold that includes one and the other molds, clamps a workpiece with the one and the other molds, and performs resin sealing, The one mold has a cavity recess filled with resin at the time of resin sealing, and the other mold is provided with a plurality of grooves opened in a mold clamping surface on which the workpiece is arranged. 1 mold block and a plurality of second mold blocks provided in each of the plurality of grooves, and a gap between the inner wall surface of the groove and the outer wall surface of the second mold block A suction path for sucking the workpiece is provided, and a tip end of the second mold block facing the mold clamp surface from the groove is chamfered in a tapered shape.

  According to this, by providing the groove for sucking the workpiece, the area for attracting the workpiece can be made larger than that of the circular hole, and the workpiece can be sucked and held flat on the mold clamping surface. Further, by providing the second mold block in the groove and chamfering the tip of the second mold block in a tapered shape, it is possible to ensure the work adsorbability. In addition, since the tip of the second mold block is tapered and chamfered, the portion of the cleaning sheet that has entered the suction path has a thin tip and a base (base end) that is thick. The whole can be removed.

  In the resin-sealed mold, the first mold block has a molding region facing the cavity recess and a non-molding region around the molding region, and the groove is provided in the non-molding region. It is preferable.

  According to this, for example, even if a lead frame with a tape attached thereto is used as a workpiece, the groove is provided around the molding region (cavity recess) (non-molding region). The tape can be prevented from being pushed into the groove, and resin leakage can be prevented.

  Further, in the resin-sealed mold, a flange portion is provided at a base end of the second mold block, and the flange portion is assembled by being pressed by the first mold block. Is preferred.

  According to this, it is possible to prevent the second mold block from coming out of the groove.

  In the resin sealing method using the resin-sealed mold, (a) in a state where the mold is opened, placing the work on which the tape is attached to the first mold block on the tape side; (B) After the step (a), the work is sucked from the groove and clamped with the one and other molds while being adsorbed to the first mold block; and (c) the step (b) And filling the resin into the cavity recess and heat curing the resin in the cavity recess.

  According to this, resin leakage can be prevented, productivity can be improved, and manufacturing yield can be improved.

  In the method for cleaning the resin-sealed mold, (a) a step of placing a cleaning sheet on the first mold block of the resin-sealed mold that has been opened, and (b) after the step (a) A step of filling the cleaning sheet clamped with the one and other molds and filling the cleaning sheet between the one and other molds and heat-curing; and (c) after the step (b) And opening the mold to remove the cleaning sheet and cleaning the mold clamping surface.

  According to this, it is possible to prevent the cleaning sheet remaining on the mold clamping surface and improve the maintainability.

  If the effect acquired by a typical thing is simply demonstrated among the invention disclosed in this application, the resin sealing metal mold | die which can ensure workpiece | work adsorption | suction property can be provided.

It is a schematic layout figure of the resin sealing metal mold | die in one Embodiment of this invention. It is a schematic sectional drawing in the AA of FIG. It is a schematic layout figure of the block in a groove | channel in one Embodiment of this invention. It is a schematic sectional drawing in the AA of FIG. It is a schematic sectional drawing in the BB line of FIG. It is a schematic sectional drawing of the resin sealing metal mold | die in the manufacturing process in one Embodiment of this invention. It is a schematic sectional drawing of the resin sealing metal mold | die in the manufacturing process following FIG. It is a schematic sectional drawing of the resin sealing metal mold | die in the manufacturing process following FIG. It is a schematic sectional drawing of the resin sealing metal mold | die in the manufacturing process following FIG. It is a schematic sectional drawing of the resin sealing metal mold | die in the manufacturing process following FIG.

  In the following embodiments of the present invention, the description will be divided into a plurality of sections when necessary. However, in principle, they are not irrelevant to each other, and one of them is related to some or all of the other modifications, details, etc. It is in. For this reason, the same code | symbol is attached | subjected to the member which has the same function in all the figures, and the repeated description is abbreviate | omitted.

  In addition, the number of components (including the number, numerical value, quantity, range, etc.) is limited to that specific number unless otherwise specified or in principle limited to a specific number in principle. It may be more than a specific number or less. In addition, when referring to the shape of a component, etc., it shall include substantially the same or similar to the shape, etc., unless explicitly stated or in principle otherwise considered otherwise .

  First, the resin sealing apparatus 100 provided with the resin sealing mold 10 in the present embodiment will be described mainly with reference to FIGS. 1 and 2. FIG. 1 is a schematic layout diagram for explaining the positional relationship of the constituent members of the resin-sealed mold 10 in a plan view parallel to the mold clamping surface when the workpiece W is clamped. FIG. It is a schematic sectional drawing in the -A line.

  In the case of mass production, the resin sealing device 100 is configured to include at least one press part (resin sealing mold 10) between a supply part (not shown) and a storage part. In this press section, the resin sealing mold 10 having a pair of upper mold 11 and lower mold 12 clamps the work W with the upper mold 11 and the lower mold 12 and performs resin sealing by the transfer method. In the supply unit, preparation and processing for supplying the workpiece W (molded product) and resin (for example, tablet-shaped, granular or liquid mold resin) to the pot 13 of the press unit are performed. In the storage section, preparation and processing for storing the workpiece W (molded product) molded with resin sealing are performed. A loader (not shown) for carrying in the press part and an unloader (not shown) for carrying out from the press part are used for transporting the workpiece W and the resin between the supply part, the press part, and the storage part. These are constituted by a known mechanism.

  The workpiece W is obtained by mounting, for example, a chip component (for example, a semiconductor chip such as a CPU or a component such as a chip capacitor) on a substrate 101 (for example, an organic substrate on which a lead frame or wiring is formed). . In the workpiece W shown in FIG. 1, a resin sealing portion (resin-filled with a cavity recess 14) that seals a chip component on a substrate 101 having a rectangular shape in plan view (longitudinal direction is X direction). Are formed at equal intervals in the X direction.

  The upper mold 11 has a plurality of cavity recesses 14 (four in FIG. 1 and FIG. 2) that are filled with resin during resin sealing (the cavity C is formed during resin sealing). In addition, it is good also as the upper mold | type 11 which has one cavity recessed part 14 (it becomes the cavity C at the time of resin sealing) with respect to one workpiece | work W. FIG. The cavity recess 14 has a rectangular shape in plan view, and has an inner wall surface (side surface) and a bottom surface, and is opened at the mold clamping surface of the upper mold 11.

  Moreover, the metal mold | die 12 has the insert 15 (1st metal mold | die block) by which the workpiece | work W is arrange | positioned. The insert 15 is provided with a plurality of suction grooves 16 (indicated by broken lines in FIG. 1) that open to the mold clamping surface. The work W is sucked to the mold clamping surface of the insert 15 by air suction from the suction groove 16.

  The insert 15 has a plurality of molding regions 20 facing the cavity recesses 14 on the mold clamping surface and a non-molding region around the molding regions 20. More specifically, the molding region 20 is a region having the same shape and the same size as the cavity concave portion 14 in a plan view shown in FIG. 1 and is secured (defined) on the mold clamping surface of the insert 15. In this way, the insert 15 has a mold clamping surface in which the molding region 20 and its periphery (non-molding region) are integrated.

  An adsorption groove 16 is provided along the molding region 20 in a non-molding region around the molding region 20. More specifically, as shown in FIG. 1, the suction grooves 16 are arranged in a row in the Y direction while maintaining a predetermined distance from the periphery of both sides (X direction side) of one molding region 20 (cavity recess 14). It extends two by two. That is, four suction grooves 16 are provided around one molding region 20. Further, since the upper mold 11 is provided with the plurality of cavity recesses 14, the suction grooves 16 are also provided between the adjacent molding regions 20.

  By providing the suction groove 16 for sucking the workpiece W in this way, the area for sucking the workpiece W is made larger than the circular hole (suction path) described in Patent Document 1, for example. The adsorptivity to W can be improved. Thereby, even if it is going to generate | occur | produce a curvature to the workpiece | work W by metal mold | die temperature, generation | occurrence | production of curvature is suppressed by adsorption | suction force, and the workpiece | work W can be hold | maintained at the mold clamping surface more flatly.

  Here, in the present embodiment, the mold clamping surface of the insert 15 on the pot 13 side (Y direction side) of the molding region 20 is provided with a runner gate in the opposed upper mold 11, so that an adsorption groove is provided. Not. Moreover, since the air vent is provided in the upper mold | type 11 which opposes the metal mold clamp surface of the insert 15 on the opposite side to the pot 13 side (Y direction side) of the shaping | molding area | region 20, the adsorption | suction groove | channel is not provided. If no air vent is provided, for example, two suction grooves 16 extending in the X direction may be provided while maintaining a predetermined distance from the periphery of the molding region 20 on the side opposite to the pot 13 side (Y direction side). In this case, the adsorptivity to the workpiece W can be further improved.

  The lower mold 12 has a plurality of in-groove blocks 17 (second mold blocks) provided in each of the plurality of suction grooves 16. The shape and fixing structure of the in-groove block 17 will be described with reference to FIG. FIG. 3 is a schematic layout diagram for explaining the positional relationship of the in-groove block 17 in a plan view parallel to the mold clamping surface, and FIG. 4 is a schematic cross-sectional view taken along line AA in FIG. FIG. 4 is a schematic sectional view taken along line BB in FIG. 3.

  A thin plate-like groove is formed (provided) between the inner wall surface of the suction groove 16 and the outer wall surface of the groove inner block 17 so as to form (provide) a gap 22 having a suction path 21 for sucking the workpiece W into the air. An inner block 17 is provided in the suction groove 16. The gap 22 communicates with a gap 24 provided between the base 23 (mold block) provided in the lower mold 12 and the insert 15 to form a suction path 21. Further, the gap 24 communicates with a suction mechanism (not shown) provided outside the mold (for example, a vacuum pump). With such a configuration, the workpiece W is sucked to the mold clamping surface of the insert 15 by air suction from the suction groove 16 through the suction path 21.

  In the groove block 17 provided in the suction groove 16, the tip of the insert 15 facing the mold clamp surface is chamfered in a tapered shape. More specifically, at the tip of the in-groove block 17 having a rectangular shape in plan view (see FIG. 3), the tapered surface 17a is cut off with the corners on both sides (X direction side) inclined while leaving a part of the end face. , 17a are formed. A part (end surface) of the tip of the block in the groove comes into contact with the workpiece W when the workpiece W is arranged on the insert 15.

  Thus, even in the configuration in which the in-groove block 17 is provided (inserted) in the suction groove 16, the tip of the in-groove block 17 is chamfered (tapered) (see FIG. 4). ) In the gap 22, the distance on the distal end side in the Z direction is wider than the other part of the in-groove block 17 (for example, from the middle to the proximal end side). Accordingly, the area for adsorbing the workpiece W to the mold clamping surface of the insert 15 can be increased, and the adsorbability to the workpiece W can be ensured.

  On the base end side opposite to the tip of the in-groove block 17, a flange portion 17b is extended in a direction extending from the middle to the tip side groove width (width in the Y direction in FIG. 5). The flange portion 17 b is pressed against the base 23 side by the insert 15. More specifically, the flange 15 b is sandwiched between the base 23 and the insert 15 by attaching the insert 15 to the base 23 by screwing, and the in-groove block 17 is fixed and assembled. According to this, it is possible to easily prevent the in-groove block 17 from coming out of the suction groove 16. In addition, although it can also be set as the structure assembled by screwing the block 17 in a groove | channel to the base 23, the structure which provides the flange part 17b and presses with the insert 15 by the point which assembles the thin plate-shaped block 17 in a groove | channel is easier. is there.

  Next, a resin sealing method using the resin sealing mold 10 (resin sealing device 100) in the present embodiment will be described mainly with reference to FIGS. 6 to 10 are schematic cross-sectional views of the resin-sealed mold 10 during the manufacturing process. In addition, it demonstrates using the lead frame 101 (board | substrate 101) by which tape T (for example, polyimide tape) was affixed on the whole back surface as the workpiece | work W. FIG.

  First, in a state where the mold is opened, the work W to which the tape T is attached is placed (carrying in) on the mold clamping surface of the insert 15 (lower mold 12) with the tape T side down. Further, the resin is supplied to the pot 13. Next, as shown in FIG. 6, the workpiece W is sucked from the suction groove 16 (suction path 21) (indicated by an arrow in FIG. 6) on the mold clamping surface of the insert 15 via the tape T. The upper mold 11 and the lower mold 12 are clamped (closed) while adsorbed.

  According to this, it is possible to ensure flatness and to attract the work to the mold clamping surface in the non-molding region. For example, a member mounted on the workpiece W (for example, a bonding wire electrically connected to a semiconductor chip) and the inner surface (for example, the bottom surface) of the cavity recess 14 come into contact with each other to prevent a product defect from occurring. can do.

  Subsequently, the sealing resin R supplied to the pot 13 is pressed by a plunger (not shown) that slides inside the pot 13, and the resin is filled in the cavity C (cavity recess 14) as shown in FIG. After that, the sealing resin R in the cavity C is heated and cured. As a result, one surface of the workpiece W (the surface on which the chip component is mounted) is resin-sealed. In the present embodiment, the in-groove block 17 is provided in the suction groove 16, and the tip of the in-groove block 17 is chamfered in a tapered shape, so that the work W adsorbability can be ensured.

  By the way, as shown in FIGS. 6 and 7, when there is a suction groove 116 (or suction hole) opening in the mold clamping surface in the molding region 20 (indicated by a broken line in the figure), the lead frame 101 is removed. Under the processed (penetrated) portion, it is conceivable that the tape T peels off without being able to withstand the resin pressure, and the tape T enters the suction groove 116. In this case, the sealing resin R leaks and adheres to the back surface of the lead frame 101 at the location of the peeled tape T.

  Therefore, in the present embodiment, the suction groove 16 is provided around the molding region 20 (non-molding region), that is, the suction groove 16 is provided in a region where the sealing resin R does not reach. For example, even if the lead frame 101 with the tape T attached thereto is used as the work W, the tape T is not pushed into the suction groove 16 due to the suction operation or the resin pressure, so that resin leakage can be prevented. Generation of bleeding can be prevented. Further, when there is no resin leakage, it is not necessary to add a work process for removing the bleed, so that productivity can be improved.

  Subsequently, after the mold is opened and the workpiece W is taken out, a cleaning method (cleaning process) for the resin-sealed mold 10 is performed. Specifically, as shown in FIG. 8, a cleaning sheet S (for example, a base material made of an unvulcanized rubber fabric) is disposed on the insert 15. Subsequently, as shown in FIG. 9, the cleaning sheet S is clamped by the upper mold 11 and the lower mold 12, and the molten cleaning sheet S is filled between the upper mold 11 and the lower mold 12 to be cured by heating. Subsequently, as shown in FIG. 10, the mold is opened, the cleaning sheet S is removed, and the mold clamping surface is cleaned.

  At this time, since the tip of the in-groove block 17 is chamfered, a part Sa of the cleaning sheet S has a thin tip that enters the suction path 21 (suction groove 16) and a thick base (base end). . For this reason, the cleaning sheet S does not remain in the suction groove 16, and the entire cleaning sheet S can be easily removed. In this way, it is possible to prevent the cleaning sheet S from remaining from the suction grooves 16 on the mold clamping surface, thereby improving the maintainability.

  In addition, since the process of removing part of Sa from the suction path 21 after cleaning the mold clamping surface is not required, it is possible to immediately move to the resin sealing process for another workpiece W, improving the productivity. can do. The cleaning of the resin sealing mold 10 can also be performed after starting the resin sealing device 100 and before starting the first resin sealing.

  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 a plurality of cavity recesses 14 are provided in the upper mold 11 has been described. Not only this but the case where one cavity recessed part was provided in the upper mold | type may be sufficient. In the case where there is one cavity recess, only one molding region facing this is defined, and a plurality of suction grooves and a plurality of in-groove blocks are provided around it.

  For example, in the above-described embodiment, the case where the two suction grooves 16 are provided in a row in the Y direction around the molding region 20 has been described. For example, one suction groove in which two suction grooves 16 are communicated may be provided, or three suction grooves may be provided.

  For example, in the above-described embodiment, the case where the suction grooves 16 provided around the molding region 20 are provided as the two suction grooves 16 between the adjacent molding regions 20 has been described. For example, two suction grooves may be provided in each of adjacent molding regions. At this time, two rows of two suction grooves are provided between adjacent molding regions.

  For example, in the above-described embodiment, the case where the cavity concave portion 14 is provided in the upper die 11 and the insert 15, the suction groove 16 and the in-groove block 17 are provided in the lower die 12 has been described. The present invention is not limited to this, and the upper and lower mold configurations may be reversed, and a cavity recess may be provided in the lower mold, and an insert, a suction groove, and an in-groove block may be provided in the upper mold.

  For example, in the above-described embodiment, the case where the lead frame 101 with the tape T attached thereto is used as the work W has been described. However, an organic substrate (wiring board) on which a wiring layer is formed as the work may be used. .

  Further, for example, in the above-described embodiment, the present invention has been described by taking a transfer type resin-sealed mold as an example, but the present invention can also be implemented in a resin-sealed mold for compression molding.

10 Resin sealing mold 11 Upper mold (first mold)
12 Lower mold (second mold)
14 Cavity recess 15 Insert (first mold block)
16 Adsorption groove 17 Block in groove (second mold block)
21 Suction path 22 Clearance W Workpiece

Claims (5)

A resin-sealed mold that includes one and the other molds, clamps a workpiece with the one and the other molds, and performs resin sealing,
The one mold has a cavity recess filled with resin at the time of resin sealing,
The other mold includes a first mold block provided with a plurality of grooves opened in a mold clamping surface on which the workpiece is disposed, and a plurality of second molds provided in each of the plurality of grooves. A mold block,
In the gap between the inner wall surface of the groove and the outer wall surface of the second mold block, a suction path for sucking the workpiece is provided,
The resin-sealed mold, wherein a tip of the second mold block facing the mold clamping surface from the groove is chamfered in a tapered shape. In the resin-sealed mold according to claim 1,
The first mold block has a molding region facing the cavity recess and a non-molding region around the molding region, and the groove is opened in the non-molding region. Sealing mold. In the resin-sealed mold according to claim 1 or 2,
A flange portion is provided at the base end of the second mold block,
The resin-sealed mold, wherein the flange portion is pressed and assembled by the first mold block. In the resin sealing method using the resin sealing mold according to any one of claims 1 to 3,
(A) a step of disposing the work with the tape attached thereto in the mold open state on the first mold block on the tape side;
(B) After the step (a), the step of sucking the workpiece from the groove and clamping it with the one and other molds while adsorbing to the first mold block;
(C) after the step (b), filling the cavity recess with resin and heat curing the resin in the cavity recess;
A resin sealing method comprising: In the cleaning method of the resin sealing mold according to any one of claims 1 to 3,
(A) placing a cleaning sheet on the first mold block of the resin-sealed mold that has been opened;
(B) After the step (a), the step of clamping and melting the cleaning sheet with the one and the other molds, filling between the one and the other molds, and heat-curing the cleaning sheet;
(C) after the step (b), opening the mold and removing the cleaning sheet to clean the mold clamping surface;
A method for cleaning a resin-sealed mold, comprising:

Images