JP2009066903A - Resin sealing mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin sealing mold, wherein closing ability in a closed space is not prevented by a work of a thick-controlling mechanism (movable cavity structure) even when a thick-controlling mechanism is adopted, and further a controlling width of the thick-controlling mechanism can be kept large and still further maintenance ability is excellent. <P>SOLUTION: The resin sealing mold includes a closing structure capable of closing parts around a substrate plate 20, a pressure-reducing mechanism capable of reducing pressure in the closed space closed by the closing structure, a thick-controlling mechanism 13 movable on a surface of a bottom mold 7 in a direction of an opposite side in order to absorbing an error of a thickness of the substrate plate 20, and a suction mechanism for adhering and fixing the substrate plate 20 to a surface of the bottom mold 7 under the condition that the substrate plate 20 is clamped by the opposite upper and bottom molds 1 and 7, whereby at least a part of a suction flow in the suction mechanism can be elongated or deformed in the opposite direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a technical field of a resin sealing device that seals a molded product on which a semiconductor chip is mounted with resin.

  Conventionally, a resin-sealed mold disclosed in Patent Document 1 is known.

  In the resin-sealed mold described in Patent Document 1, in order to absorb a thickness error of a substrate that is a molded product and secure an appropriate clamp (clamp by an upper mold and a lower mold), A so-called “movable cavity structure (plate thickness correction mechanism)” in which a part of the surface of the mold can move up and down is employed. This possible cavity structure is realized by appropriately sinking the movable cavity indicated by the disc spring by the applied pressure.

  Further, there is a case in which a pressure in the cavity is reduced when resin sealing is performed, thereby suppressing generation of voids that may occur in the resin and improving the quality of the resin sealing. For example, this method is realized by forming a sealed space including the cavity by closing the upper mold and the lower mold and sucking air in the sealed space.

Japanese Patent Laid-Open No. 11-16932

  The inventor adopts the movable cavity structure as described in Patent Document 1 to flexibly cope with the substrate thickness error, and at the same time, the pressure inside the cavity is reduced to improve the quality of the resin sealing. I got the idea of trying.

  In order to realize the idea, a sealed structure that can form a sealed space around the substrate to be clamped (for example, a seal member is arranged around the surface of the upper mold and the lower mold) is adopted. It is necessary to form a sealed space and clamp the substrate after decompressing the sealed space (if the substrate is clamped with a mold before the sealed space is formed and decompressed, the decompression will be insufficient. There is.)

  However, if the inside of the sealed space is depressurized while the substrate is simply placed on the mold surface (not clamped), the substrate may be lifted by the depressurization. Therefore, in order to avoid this lifting, it is necessary to decompress the inside of the sealed space after the substrate placed on the mold surface is fixed by suction, for example. At this time, when a so-called “movable cavity structure” is employed on the mold side (for example, the lower mold side) on which the substrate is to be sucked and fixed, the mold should be sucked from the hole opened in the movable mold surface. A suction path leading to the outside of the mold must be formed.

  In forming such a suction path, the inventor has developed a resin-sealed mold Y having a structure shown in FIG. 3 (unknown at the time of filing). This resin-sealed mold Y is composed of an upper mold 1 and a lower mold 7.

  The upper mold 1 includes an upper mold base 3, an upper mold cavity block 2 that is suspended substantially at the center of the upper mold base 3, and an upper mold frame block 4 that is disposed so as to surround the upper mold cavity block 2. And an upper mold end plate 5 disposed between the upper mold frame block 4 and the upper mold cavity block 2. Further, on the lower surface side (lower mold 7 side) of the upper mold block 4, a seal capable of forming a sealed space between the upper mold 1 and the lower mold 7 by contacting the lower mold 7. A member 6 is arranged. A cavity 30 filled with resin (not shown) is formed on the surface of the upper mold cavity block 2 (surface on the lower mold 7 side).

  On the other hand, the lower mold 7 includes a lower mold base 9, a lower mold movable cavity block 8 disposed substantially at the center of the lower mold base 9, and a lower mold frame provided around the lower mold movable cavity block 8. A block 10 and a lower mold end plate 11 arranged between the lower mold frame block 10 and the lower mold movable cavity block 8 are provided. The lower mold movable cavity block 8 which is a part of the surface of the lower mold 7 (the upper mold 1 side surface) is supported from the lower mold base 9 via the plate thickness adjusting mechanism 13. The plate thickness adjusting mechanism 13 includes a plurality of disc springs 12, and constantly urges the lower mold movable cavity block 8 upward (upward in FIG. 1) and also applies the lower mold movable cavity block 8 to the lower mold movable cavity block 8. On the other hand, it is possible to sink when a downward pressure is applied. That is, the thickness error of the substrate 20 is absorbed by moving the lower mold movable cavity block 8 up and down according to the thickness of the substrate (molded product) 20 clamped by the upper mold 1 and the lower mold 7. Is possible.

  The lower mold movable cavity block 8 is embedded with a pipe-like suction path 8A for fixing the substrate 20 by suction. The suction path 8 </ b> A provided in the lower mold movable cavity block 8 communicates with the outside of the resin-sealed mold Y through the end plate 11 and the lower mold block 10. Further, a suction device (for example, a vacuum pump) (not shown) is connected to the communication destination, and the air in the suction path 8A can be sucked at a predetermined timing. Further, the lower mold block 10 is provided with an O-ring 14 so as to surround the suction path 8A. When the O-ring 14 is allowed to move to some extent in the vertical direction of the suction path 8A, a sealed space is formed. It is possible to maintain the hermeticity.

  However, when such a structure is adopted, it has been difficult to accurately maintain the reduced pressure state in the sealed space for a long period of time. That is, pressure may leak from the portion of the suction path 8A and the O-ring 14.

  The lower mold movable cavity block 8 moves in the vertical direction (vertical direction in FIG. 3) according to the thickness of the substrate 20 to be clamped, and the suction path 8A also moves up and down with the movement. Then, the suction path 8A generates a force for crushing the O-ring 14, and in particular, an adhesion force (adhesion force between the suction path 8A and the O-ring 14) at a portion of the O-ring 14 opposite to the crushed side. Decreases. As a result of repeated crushing, the O-ring 14 is deteriorated, and outside air flows into the sealed space from the portion where the adhesion force is reduced, so that it is difficult to accurately maintain the decompressed state in the sealed space. It is considered a thing. This also means that, if viewed differently, the movable range of the lower mold movable cavity block 8 (adjustment width of the plate thickness adjustment mechanism) is limited, and the width of the substrate corresponding to the thickness error is limited. There was also a problem. Further, in order to ensure an appropriate sealed state, it is necessary to frequently replace the O-ring, and there is a problem that the maintenance work is complicated.

  The present invention has been made to solve these problems, and even when a plate thickness adjusting mechanism (movable cavity structure) is adopted, the sealing performance of the sealed space is hindered by the action of the plate thickness adjusting mechanism. In addition, an object of the present invention is to provide a resin-sealed mold that can secure a large adjustment width of the plate thickness adjusting mechanism and is excellent in maintainability.

  The present invention is an improvement of the above-described resin-sealed mold Y. That is, a resin-sealed mold that clamps a molded product by opposing first and second molds and seals at least a part of the molded product with resin, and clamps the molded product In order to absorb the thickness error of the molded product, a sealed structure capable of sealing the periphery of the molded product, a decompression mechanism capable of decompressing the sealed space sealed by the sealed structure, A plate thickness adjusting mechanism that allows the surface of the second mold on the first mold side to move in the facing direction, and suction for fixing the article to be molded to the surface of the second mold And at least a part of the suction path in the suction mechanism can be expanded / contracted or deformed in the facing direction.

  By adopting such a structure, even if the plate thickness adjusting mechanism acts and the surface of the second mold moves in the opposite direction, the suction path itself expands and contracts in the moving direction, so that the movement It is possible to absorb the minute.

  Specifically, for example, the parallel member includes a tubular member having a hollow portion extending in the facing direction, a fitting member fitted into the hollow portion, and the fitting member with respect to the tubular member. And a seal member capable of maintaining the hermeticity of the suction path while allowing sliding in the opposite direction, even when the plate thickness adjusting mechanism is operated, a part of the seal member is pushed. No crushing force is applied, and the sealing performance of the sealing member can be maintained over a long period of time. As a result, it is not necessary to frequently replace the seal member, so that maintainability is also improved.

  Further, if the seal member is an O-ring disposed between the tubular member and the fitting member, it can be realized easily and at low cost.

  In addition, the same effect can be exhibited by configuring at least a part of the parallel portion as a bellows.

  Further, if the pressure in the suction path after suction by the suction mechanism is set lower than the pressure after decompression of the sealed space that is decompressed by the decompression mechanism, Lifting can be surely prevented.

  By applying the present invention, even when a plate thickness adjusting mechanism (movable cavity structure) is employed, the sealing property of the sealed space is not hindered by the action of the plate thickness adjusting mechanism, and the plate thickness adjusting mechanism is further adjusted. It is possible to provide a resin-sealed mold that can secure a large width and is excellent in maintainability.

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

  FIG. 1 is an immediate sectional view of a resin-sealed mold X showing an example of an embodiment of the present invention. FIG. 2 is an enlarged view of the periphery of the adapter in FIG.

<Configuration of resin-sealed mold>
The resin sealing mold X includes an upper mold 1 and a lower mold 7.

  The upper mold 1 includes an upper mold base 3, an upper mold cavity block 2 that is suspended substantially at the center of the upper mold base 3, and an upper mold frame block 4 that is disposed so as to surround the upper mold cavity block 2. And an upper mold end plate 5 disposed between the upper mold frame block 4 and the upper mold cavity block 2. Further, on the lower surface side (lower mold 7 side) of the upper mold block 4, a seal capable of forming a sealed space between the upper mold 1 and the lower mold 7 by contacting the lower mold 7. A member 6 is arranged. The “sealing structure” is realized by the seal member 6, the upper mold block 4 and the lower mold block 10 described later. A cavity 30 filled with resin (not shown) is formed on the surface of the upper mold cavity block 2 (surface on the lower mold 7 side).

  On the other hand, the lower mold 7 includes a lower mold base 9, a lower mold movable cavity block 8 disposed substantially at the center of the lower mold base 9, and a lower mold frame provided around the lower mold movable cavity block 8. A block 10 and a lower mold end plate 11 arranged between the lower mold frame block 10 and the lower mold movable cavity block 8 are provided. The lower mold movable cavity block 8 which is a part of the surface of the lower mold 7 (the upper mold 1 side surface) is supported from the lower mold base 9 via the plate thickness adjusting mechanism 13. The plate thickness adjusting mechanism 13 includes a plurality of disc springs 12, and constantly urges the lower mold movable cavity block 8 upward (upward in FIG. 1) and also applies the lower mold movable cavity block 8 to the lower mold movable cavity block 8. On the other hand, it is possible to sink when a downward pressure is applied. That is, the thickness error of the substrate 20 is absorbed by the sinking of the lower mold movable cavity block 8 according to the thickness of the substrate (molded product) 20 clamped by the upper mold 1 and the lower mold 7. Is possible.

  The lower mold movable cavity block 8 is formed with a suction path 8A for fixing the substrate 20 by suction. The suction path 8A provided in the lower mold movable cavity block 8 is open to the side surface (left side surface in FIG. 1) of the lower mold movable cavity block 8. An adapter (fitting member) 15 is provided on the side surface. A small-diameter portion 15B is provided on the lower surface side of the adapter 15 (see FIG. 2). The adapter 15 is provided with a through hole 15A. The through hole 15A is turned 90 degrees in the adapter 15, and one of the through holes 15A is open at a substantially central portion of the small diameter portion 15B. Furthermore, the adapter 15 is provided in such a manner that the suction path 8A opened on the side surface of the lower mold movable cavity block 8 and the through hole 15A of the adapter 15 communicate with each other. As a result, the suction path 8 </ b> A extending in the substantially horizontal direction in the lower mold movable cavity block 8 is converted to a downward direction.

  The small diameter portion 15B is loosely fitted (fitted) into the hollow portion 16A of the cylindrical member 16 erected from the lower mold base 9. Further, an O-ring (seal member) 14 is provided between the tubular member 16 and the small diameter portion 15B of the adapter 15 so that the sealing between the hollow portion 16A of the tubular member 16 and the outside is maintained. Yes. As a result, the small-diameter portion 15B of the adapter 15 can be slid in the vertical direction with respect to the tubular member 16 while maintaining hermeticity via the O-ring 14.

  Further, a suction path 9 </ b> A is formed in the lower mold base 9 from the standing position of the cylindrical member 16 toward the outside of the resin-sealed mold X. As a result, the suction path 9A, the hollow portion 16A of the cylindrical member 16, the through-hole 15A in the adapter 15 and the suction path 8A provided in the lower mold movable cavity block 8 are all in communication, and the entire communication path is 1 It is configured to function as one suction path. Note that a suction device such as a vacuum pump is connected to the suction path 9A. The suction device and the suction path (suction path 8A, through hole 15A, hollow portion 16A, suction path 9A) constitute a suction mechanism.

  By adopting such a configuration, as the lower mold movable cavity block 8 moves in the vertical direction, the small diameter portion 15B slides up and down while being in close contact with the O-ring 14. As a result, the suction path (suction path 8A, The portions of the through hole 15A, the hollow portion 16A, and the suction path 9A) arranged in parallel with the opposing direction of the upper mold 1 and the lower mold 7 can be expanded and contracted. Of course, the mode of expansion and contraction is not limited to the above-described one. For example, the expansion and contraction of the suction path can be realized by disposing a “bellows” in a part of the parallel portion.

  Although not shown, the resin-sealed mold X is provided with a pressure reducing mechanism for reducing the pressure in the sealed space formed by contacting the upper mold 1 and the lower mold 7 via the seal member 6. ing. This decompression mechanism is configured by an independent path different from the above-described suction path (suction path 8A, through hole 15A, hollow portion 16A, suction path 9A).

<Operation of resin-sealed mold>
In a state where the upper mold 1 and the lower mold 7 are opened (separated), the substrate (molded product) 20 is transported onto the lower mold movable cavity block 8 by a transport mechanism (not shown). When the conveyance is completed, air in the suction path (suction path 8A, through hole 15A, hollow portion 16A, suction path 9A) is sucked by a suction device such as a vacuum pump, and the substrate 20 is placed on the lower mold movable cavity block 8. Adsorb and fix. Simultaneously with or after the adsorption, the upper mold 1 and the lower mold 7 approach each other. By this approach, the upper mold 1 and the lower mold 7 come into contact with each other through the seal member 6. From this contact, the periphery including the substrate 20 becomes a sealed space.

  After the sealed space is formed, the pressure-reducing mechanism depressurizes the sealed space to a predetermined pressure. In the present embodiment, since the substrate 20 has already been adsorbed and fixed on the surface of the lower mold movable cavity block 8 at this stage, the substrate 20 does not float even by the reduced pressure. In particular, in the present embodiment, in the suction path (suction path 8A, through-hole 15A, hollow portion 16A, suction path 9A) after suction by the vacuum pump, rather than the pressure after decompression of the sealed space decompressed by the decompression mechanism. Since the pressure is set lower, the substrate 20 is surely prevented from being lifted.

  Thereafter, the upper mold 1 and the lower mold 7 are further brought closer, and the substrate 20 is clamped. With the clamp, the lower mold movable cavity block 8 sinks according to the thickness of the substrate 20. That is, the thickness error of the substrate 20 is absorbed and adjusted by the “sinking”. In the present embodiment, since the above-described configuration (particularly the configuration of the suction path) is employed, even when the lower mold movable cavity block 8 moves up and down, the suction path itself expands and contracts in the movement direction. It is possible to absorb the movement. At this time, since the force which crushes a part of O-ring 14 is not added, the confidentiality of the O-ring 14 and the small diameter part 15B does not deteriorate. That is, even when the lower mold movable cavity block 8 moves up and down, the force does not apply to the O-ring 14 due to the movement, so that the sealing performance of the O-ring 14 can be maintained for a long period of time. As a result, it is not necessary to frequently replace the O-ring 14, so that maintainability is also improved.

  In the above embodiment, a part of the suction path is arranged in parallel with the opposing direction of the mold, and the parallel part expands and contracts (or deforms). However, the suction paths do not have to be parallel as long as the movement of the opposing component of the mold can be absorbed. For example, even if the suction path extends in a direction orthogonal to the facing direction, it is possible to absorb the movement in the facing direction if a part of the suction path is formed of a flexible pipe. .

  The present invention is suitable as a resin-sealed mold, particularly as a transfer-type resin-sealed mold.

Immediate sectional view of resin-sealed mold X showing an example of an embodiment of the present invention 1 is an enlarged view around the adapter in FIG. Side sectional view of the resin-sealed mold Y before improvement, which was conceived by the inventor

Explanation of symbols

X ... Resin sealing mold 1 ... Upper mold 2 ... Upper mold cavity block 3 ... Upper mold base 4 ... Upper mold frame block 5 ... Upper mold end plate 6 ... Seal member 7 ... Lower mold 8 ... Lower mold movable cavity Block 8A ... Suction path 9 ... Lower mold base 9A ... Suction path 10 ... Lower mold block 11 ... Lower mold end plate 12 ... Belleville spring 13 ... Plate thickness adjustment mechanism 14 ... O-ring 15 ... Adapter 15A ... Through hole 15B ... Small diameter Part 16: Cylindrical member 20 ... Substrate (molded product)
30 ... cavity

Claims (6)

A resin-sealed mold that clamps a molded product by opposing first and second molds and seals at least a part of the molded product with resin,
A sealed structure capable of sealing the periphery of the molded product in a state where the molded product is clamped,
A decompression mechanism capable of decompressing the sealed space sealed by the sealed structure;
In order to absorb the thickness error of the molded article, a plate thickness adjusting mechanism that enables the surface of the second mold on the first mold side to be moved in the facing direction;
A suction mechanism for adsorbing and fixing the article to be molded on the surface of the second mold,
A resin-sealed mold, wherein at least a part of a suction path in the suction mechanism can be expanded and contracted or deformed in the facing direction. In claim 1,
A resin-sealed mold, wherein at least a part of a suction path in the suction mechanism is arranged in parallel with the facing direction, and the parallel part can be expanded and contracted or deformed in the facing direction. In claim 2,
The parallel part has a tubular member having a hollow portion extending in the facing direction, a fitting member fitted into the hollow portion, and sliding of the fitting member with respect to the tubular member in the facing direction. And a sealing member capable of maintaining the airtightness of the suction path while allowing the resin-sealing mold. In claim 3,
The sealing member is an O-ring disposed between the tubular member and the fitting member. A resin-sealed mold. In claim 1,
A resin-sealed mold, wherein at least a part of the suction path is a bellows. In any one of Claims 1 thru | or 5,
The resin-sealed mold, wherein the pressure in the suction path after suction by the suction mechanism is lower than the pressure after decompression of the sealed space decompressed by the decompression mechanism.

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