JP5352896B2 - Transfer molding method and transfer molding apparatus - Google Patents

Description

  The present invention relates to a transfer molding method and a transfer molding apparatus for resin molding a semiconductor device.

In the case of sealing a thin semiconductor device with resin, the present applicant has proposed various resin molding devices in order to improve the resin filling property into the cavity and prevent the generation of voids.
For example, in a resin mold apparatus in which a movable pin is provided above and below the cavity recess of the mold and a dummy cavity connected to the opposite side of the gate communicating with the cavity recess, the movable pin and the ejector pin are lowered to the retracted position. When the cavity is filled with molten resin, the movable pin and the ejector pin are pushed out to the proper position while the plunger is pressure-fed, and the excess resin overflows into the dummy cavity. Unfilling and voids are prevented from occurring (see Patent Document 1).

  Also, in a resin molding apparatus that resin seals between metal pillars of a semiconductor wafer provided with metal pillars as workpieces, the workpiece is placed in a cavity recess formed by a movable cavity block and a movable clamp, and a mold die is placed. Clamp and actuate the plunger to fill the molten resin. Then, by clamping the movable cavity block so that the cavity volume is reduced while the movable clamp clamps the workpiece, the sealing resin is made to flow backward to the pot side and the plunger is pushed back so as to be molded to a predetermined resin thickness. (See Patent Document 2).

JP-A-07-112453 JP 2001-79878 A

However, when the thickness of the package part is reduced to, for example, about 0.3 mm, the cured sealing resin is easily cured, and the range in which the resin can flow is limited by transfer molding. In addition, when the molten resin overflows from the cavity recess in order to eliminate unfilled sealing resin and voids, the resin pressure tends to become unstable, and the resin flow along the flow path of the resin flowing from the gate is relatively Large diameter fillers (phosphors in the case of white LEDs) are unevenly distributed, and minute bubbles are gathered and distributed to form flow marks. Furthermore, large wire flows are generated at the four corners of the package part (four corners of the cavity recess). In addition, a high molding resin pressure is required to prevent generation of an unfilled area that is likely to occur in a narrow gap between the bottom of the cavity and the upper surface of the semiconductor chip.
Even when a liquid resin for compression molding is used, an optimal resin is still under development, and the cost is high and mass production is difficult. It is also possible to drop and mold the pulverized resin into the cavity recess, or drop it into the cavity recess to form a resin mold. However, wire flow and voids occur, and the resin thickness is reduced to the limit. It has not yet become an effective means for solving the problem of thin molding.
Therefore, without using new equipment, a thin mold package with no distribution of filler and phosphor diameters mixed in the resin and unfilled areas of resin can be used with a resin molding apparatus by transfer molding that has been used conventionally. A technique for mass production using inexpensive resin has been desired.

  The present invention solves the above-mentioned problems of the prior art, and without using new equipment, the thickness of the package part is molded with the target thickness and the distribution of the filler diameter and phosphor diameter mixed in the resin is uneven. It is an object of the present invention to provide a transfer molding method and a transfer molding apparatus capable of mass-producing a thin package without an unfilled region of resin using an inexpensive resin.

In order to achieve the above object, the present invention comprises the following arrangement.
That is, a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. The cavity piece is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product and clamped by the clamper, and the clamper clamps the workpiece. While maintaining the predetermined first holding pressure by operating the plunger while filling the cavity recess, and after filling the resin, the cavity piece is further moved to the molding position corresponding to the thickness dimension of the molded product. Extruding and pushing back the excess resin in the cavity recess from the gate to the pot side, and actuating the plunger again Thereby comprising the step of heating and curing the left sealing resin maintaining the second pressure keeping higher than the first pressure-holding, in the step of pushing back the pot side the excess resin from the gate, the intermediate coercive lower than the first pressure-holding The excess resin is pushed back while maintaining the pressure.

Also, after heat curing the sealing resin, the clamper is characterized in that it comprises a step of releasing the molded product by moving only to the retracted position cavity pieces while clamping the workpiece.
The clamper is floatingly supported by a base block, and the cavity piece is fixed to the base block. After the clamper clamps a workpiece, the cavity piece is pushed out by further mold closing operation.
Alternatively, the clamper is fixed to a base block, the cavity piece is floatingly supported on the base block, and the cavity piece is switched between a retracted position and a molding position by a wedge mechanism.

Further, when the cavity piece is pushed out from the retracted position to the molding position, excess resin pushed back from the cavity concave portion to the gate side is absorbed by retreating the plunger into the pot.
Alternatively, the movable piston is floatingly supported on the mold cull forming surface of the clamper, and when the cavity piece is pushed from the retracted position to the molding position, the movable resin is pushed back from the cavity recess to the gate side. Absorbing is performed by retreating the piston.

The clamper clamps the workpiece by driving the press drive source for opening and closing the mold to the predetermined first press coordinate, and the plunger is operated by the transfer drive source to fill the cavity with molten resin. By maintaining the predetermined first holding pressure and lowering the resin pressure after filling the resin to an intermediate holding pressure lower than the first holding pressure, the press drive source is driven to the final second press coordinate, whereby the cavity recess The surplus resin inside is allowed to return from the gate to the pot side, and the plunger is operated again to increase the resin pressure to a predetermined second holding pressure higher than the first holding pressure, while maintaining the sealing resin. It is characterized by being heat-cured.
Alternatively, the clamp drive clamps the workpiece by driving a press drive source that opens and closes the mold to a predetermined first press coordinate, and the plunger is operated by the transfer drive source to fill the cavity with a molten resin and to perform the predetermined operation. The first drive pressure is maintained and the press drive source is driven to the third press coordinate before the final second press coordinate while the resin pressure after filling the resin is lowered to an intermediate hold pressure lower than the first hold pressure. By doing so, the excess resin in the cavity recess is allowed to return from the gate to the pot side, and the plunger is operated again to increase the resin pressure to a predetermined third holding pressure higher than the first holding pressure. The sealing resin is heat-cured as it is.

In the transfer molding apparatus, a cavity mold is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface including the cavity depression. A press drive source for opening and closing the mold, press coordinate detection means for detecting press coordinates from the drive amount of the press drive source, and sealing from a pot provided in the mold to the cavity recess a transfer drive source for driving the benefit the resin pumping plunger, a resin pressure detecting means for detecting the resin pressure acting on the plunger, and a control means for controlling each of the driving operation of the press drive source and the transfer drive source, the Resin pressure for a predetermined time from when one press coordinate is detected until the transfer drive source is activated A predetermined time for maintaining the first holding pressure, a predetermined time for maintaining the intermediate holding pressure lower than the first holding pressure, the press drive source is restarted, and the final second press coordinate or the third press coordinate before it is A timer that detects at least one of a predetermined time from when the transfer driving source is detected until the transfer driving source is restarted, and a predetermined time during which the transfer driving source is restarted and the second holding pressure is maintained; And when the timer informs that a predetermined time has elapsed, a press drive source is activated by the control means , and the mold is closed until reaching a first press coordinate where the workpiece is clamped by the clamper, With the first press coordinate detected by the coordinate detection means and the press drive source stopped, the transfer drive source is activated and sealed in the cavity recess When the oil is pumped and the resin pressure detected by the resin pressure detecting means detects the first holding pressure and a predetermined intermediate holding pressure lower than the first holding pressure, the control means ends the press drive source. By driving to the second press coordinate or the third press coordinate before that, it allows the excess resin in the cavity recess to return from the gate to the pot side, restarts the transfer drive source, and pushes the plunger. The resin is detected by being heated and pressurized while being kept at a predetermined second holding pressure higher than the first holding pressure.

By using the above transfer molding method and apparatus, the work carried into the mold is clamped by the clamper while the cavity piece is kept at the retracted position where the cavity piece is retracted by a predetermined thickness from the thickness of the molded product. The plunger is operated while being clamped to fill the cavity with the molten resin and maintain a predetermined first holding pressure. Thereby, while easily discharging the air in the cavity recess, the gap between the cavity recesses is enlarged and the melted resin can be easily filled into the cavity recess, and the unfilled region can be eliminated.
After filling the resin, the cavity piece is further pushed into the cavity recess to the molding position corresponding to the thickness dimension of the molded product, and the excess resin in the cavity recess is pushed back from the gate to the pot side to achieve the desired molding. The amount of resin can be adjusted to match the thickness of the product.
In addition, the first holding pressure may be thermally cured, but the sealing resin is heated and cured while the second holding pressure higher than the first holding pressure is maintained by operating the plunger again. Since the mixed voids can be crushed and molded, the molding quality can be improved.
Therefore, the package can be molded with the target thickness without using new equipment, and a molded product with high molding quality can be mass-produced at low cost.

  In addition, after filling the resin, the cavity piece is further pushed out to the molding position corresponding to the thickness dimension of the molded product while maintaining the intermediate holding pressure lower than the first holding pressure so that the excess resin in the cavity recess is pushed back from the gate to the pot side. If it does, return of the surplus resin with which the cavity recessed part was returned from the gate to the pot side can be promoted. Thereby, by maintaining the first holding pressure after filling the resin, the resin pressure in the cavity becomes too high to prevent the resin leakage, and the resistance of the resin path is increased so that the surplus resin is difficult to return from the gate to the pot side. Thus, it is possible to prevent the molded product from being damaged by increasing the viscosity of the sealing resin and reducing the fluidity.

  In addition, after the sealing resin is heat-cured, the molded product is released from the mold without any special means by releasing the molded product by moving only the cavity piece to the retracted position while the clamper clamps the workpiece. Can be easily separated.

  Further, when the cavity piece is pushed out from the retracted position to the molding position, the excess resin pushed back from the cavity concave portion to the gate side is absorbed by the retraction of the plunger into the pot, or it is movable on the pot facing surface of the clamper. Since the piston is floatingly supported with respect to the base block, excess resin pushed back from the cavity recess to the gate side when the cavity piece is pushed from the retracted position to the molding position is absorbed by the movable piston and absorbed. A space derived from the mold structure can be formed without providing a dummy cavity to absorb excess resin.

Further, by driving the press drive source to the final second press coordinate while maintaining the intermediate pressure lower than the first holding pressure after the resin filling, the excess resin in the cavity recess is moved from the gate to the pot side. The sealing resin is maintained while the resin pressure detected by positively allowing the return and restarting the transfer drive source and pushing the plunger is maintained at a predetermined second holding pressure higher than the first holding pressure. By heat-curing, a thin package having no uneven distribution of filler diameter and phosphor diameter and no resin-filled region can be mass-produced using an inexpensive resin. Further, since the voids that are the origins of the flow marks are pressed after flowing out of the cavity recesses, a package without voids and flow marks can be formed.
In addition, the press drive source is driven to the third press coordinate before the final second press coordinate while the resin pressure after the resin filling is maintained at the intermediate hold pressure lower than the first hold pressure, thereby surplus in the cavity recess The resin is positively allowed to return from the gate to the pot side, and the resin pressure detected by restarting the transfer drive source and pushing the plunger is a predetermined second holding pressure higher than the first holding pressure. By heat-curing the sealing resin while maintaining it high, the thickness of the package part can be molded as intended.

  In addition, if the transfer molding apparatus is used, the mold is closed until the first driving coordinate is reached by the press driving source activated by the control means and the workpiece is clamped by the press coordinate detecting means using the configuration of the existing mold. Then, the transfer drive source is activated and the sealing resin is pumped to the cavity recess, and the control means has a predetermined first holding pressure and a predetermined intermediate holding pressure lower than the first holding pressure. When the time is detected, by driving the press drive source to the final second press coordinate or the third press coordinate before it, the excess resin in the cavity recess is actively allowed to return from the gate to the pot side, The resin pressure detected by restarting the transfer drive source and pushing the plunger is maintained at a predetermined second holding pressure higher than the first holding pressure. And pressurized hot-press resin-sealed. Therefore, it is possible to mass-produce thin packages at low cost using existing equipment, without having to perform major setup changes, by simply detecting the press coordinates, transfer coordinates and resin pressure and controlling the drive of the press drive source and transfer drive source. Can be

  In addition, the resin pressure is maintained at an intermediate holding pressure lower than the first holding pressure for a predetermined time from when the first press coordinates are detected until the transfer driving source is activated, for a predetermined time during which the first holding pressure is maintained. The transfer drive source is restarted for a predetermined time after the press drive source is restarted for a predetermined time and the final second press coordinate or the third press coordinate before it is detected until the transfer drive source is restarted. (2) A timer for detecting at least one elapsed time of the predetermined time during which the pressure holding is maintained is provided, and when the timer informs that the predetermined time has elapsed, the control means performs the drive operation of the press drive source or the transfer drive source. Since each is controlled, the behavior of the pressing device and the behavior of the sealing resin are stabilized, and a higher quality molded product can be obtained.

FIG. 5 is a mold cross-sectional view illustrating a transfer molding operation according to the first embodiment. FIG. 5 is a mold cross-sectional view illustrating a transfer molding operation according to the first embodiment. FIG. 5 is a mold cross-sectional view illustrating a transfer molding operation according to the first embodiment. It is a graph which shows the relationship between the resin pressure by transfer molding, a transfer coordinate, and cavity depth. 6 is a mold cross-sectional view illustrating a transfer molding operation according to Embodiment 2. FIG. 6 is a mold cross-sectional view illustrating a transfer molding operation according to Embodiment 2. FIG. It is a graph which shows the relationship between the resin pressure and transfer coordinate by transfer molding, the displacement of a movable piston, and cavity depth. 10 is a mold cross-sectional view illustrating a transfer molding operation according to Embodiment 3. FIG. FIG. 10 is an explanatory diagram illustrating a configuration of a control system of a transfer molding device according to a fourth embodiment. It is a timing chart figure which shows the time change of metallic mold clamp pressure, press coordinates, resin pressure, cavity depth, and transfer coordinates by transfer molding.

  Hereinafter, preferred embodiments of a transfer molding method and a transfer molding apparatus according to the present invention will be described in detail with reference to the accompanying drawings. In the following embodiments, a transfer molding method using a mold in which a cavity recess is formed on the upper mold side and a pot is formed on the lower mold side will be described. In the transfer molding apparatus, the lower mold is described as a movable mold and the upper mold is described as a fixed mold.

First, the schematic configuration of the transfer molding apparatus will be described with reference to FIG. The mold 1 includes an upper mold 2 and a lower mold 3.
The configuration of the upper mold 2 will be described. In the upper mold 2, a cavity piece 5 (cavity block) that forms a cavity bottom is fixed to the upper mold base block 4. A clamper 6 (clamper block) for clamping the workpiece W is suspended and supported around the cavity piece 5 via a spring 8 (floating support). The clamper 6 is provided with a plurality of through holes through which the cavity piece 5 is inserted into a single plate-shaped mold. A mold cull and a mold runner gate are formed at the center of the clamper 6. A cavity recess K is formed by the cavity piece 5 and the clamper 6 disposed so as to surround the cavity piece 5. Further, an upper stopper block 9 is fixed to the upper mold base block 4 outside the clamper 6.

  A release film 10 is stretched on the mold surface including the cavity recess K. The release film 10 is sucked and held on the upper mold surface by a known suction mechanism using a gap between blocks. The release film 10 has heat resistance that can withstand the heating temperature of the mold, and is easily peeled off from the mold surface, and is a film material having flexibility and extensibility, such as PTFE and ETFE. PET, FEP, fluorine-impregnated glass cloth, polypropylene, polyvinyl chloride, etc. are preferably used. For example, a long film material is used as the release film 10, and the release film 10 is provided so as to be drawn out from a feeding roll wound up in a roll shape, passed through an upper clamping surface, and wound up onto a winding roll. By using the release film 10, it is not necessary to provide an ejector pin on the mold 1. Further, resin leakage from the movable gap around the cavity piece 5 can be prevented, and the processing accuracy of the mold is not increased more than necessary, so that the mold 1 can be manufactured at low cost.

Next, the configuration of the lower mold 3 will be described.
The lower mold base block 11 is provided with a lower mold chase block 12. A lower insert block 13 is supported on the lower chase block 12. In addition, a pot 14 is assembled at the center of the lower mold chase block 12 and the lower mold insert block 13. A plunger 15 that moves up and down by a known transfer drive mechanism is provided in the pot 14. As the plunger 15, a multi-plunger in which a plurality of plungers 15 are provided on a support block (not shown) corresponding to the plurality of pots 14 is used. An elastic member (not shown) is provided on the support portion of each plunger 15, and each plunger 15 is slightly displaced by the elasticity of the elastic member to release an excessive pressing force and adapt to variations in the resin amount of the tablet during holding. Can be done.

  On the upper surface of the lower mold insert block 13, a workpiece placing portion 13a on which the workpiece W is placed is provided. As the workpiece W, a product for single-sided molding in which a semiconductor chip is mounted on one side is used. A lower stopper block 16 is fixed to the outer peripheral side of the lower mold insert block 13 of the lower mold chase block 12. The upper mold 2 and the lower mold 3 are clamped until the upper and lower stopper blocks 9 and 16 come into contact with each other.

Here, a transfer molding method using the transfer molding apparatus will be described with reference to FIGS. As an example, the thickness of the molded product of the workpiece W is described as 0.3 mm from the substrate surface.
The right half view of FIG. 1 shows that the workpiece W is carried into the workpiece mounting portion 13a of the lower mold insert block 13, and the lower mold 3 in which the sealing resin (resin tablet) 17 is supplied to the pot 14 is raised and clamped. The state which clamped the workpiece | work W with the upper mold | type 2 by which the release film 10 was adsorbed-held on the surface is shown. At this time, the workpiece W is clamped by the clamper 6 while maintaining the retracted position in which the cavity piece 5 of the upper mold 2 is retracted by a predetermined thickness (for example, 0.2 mm) from the thickness dimension (for example, 0.3 mm) of the molded product. At this time, the upper stopper block 9 is stopped at a predetermined interval (0.2 mm) from the lower stopper block 16. At this time, the gap between the clamper 6 and the upper mold base block 4 is floatingly supported so as to have the same distance (0.2 mm).

Next, as shown in the left half view of FIG. 1, the clamper 6 operates the transfer drive mechanism (not shown) while clamping the workpiece W to raise the plunger 15, and into the cavity recess K through the die cull and runner gate. The molten resin is filled to maintain the resin pressure at a predetermined first holding pressure (for example, 80 kgf / cm ² ) (see resin pressure in FIG. 4). As a result, it is possible to easily fill the cavity recess K with the melted sealing resin 17 by enlarging the volume of the cavity recess K, thereby eliminating the unfilled region.

In the right half view of FIG. 2, after filling the resin, the cavity piece 5 is further pushed out to the molding position corresponding to the thickness dimension (eg, 0.3 mm) of the molded product, and the excess resin in the cavity recess K is removed from the gate to the pot 14 side. Push back to. Specifically, as shown in the left half of FIG. 2, the lower die 3 is further raised and the clamper 6 pushes and shrinks the spring 8 until it hits the upper die base block 4 and the upper and lower stopper blocks 9 and 16 hit. Clamp. At this time, the plunger 15 is retracted into the pot 14 to absorb excess resin (see transfer coordinates in FIG. 4).
In this way, after the clamper 6 clamps the workpiece W, the cavity piece 5 is pushed out into the cavity recess K by further mold closing operation, so that the thickness dimension (for example, 0.3 mm) of the target molded product is adjusted. The amount of resin can be adjusted (see cavity depth in FIG. 4).

Then, the left half of FIG. 2, the second holding pressure higher about 20% than the first pressure-holding with the plunger 15 is raised again (e.g. 80 kgf / cm ²⁾ by a transfer drive mechanism (e.g., 100 kgf / cm ²⁾ The sealing resin 17 is heated and cured for a predetermined time while being maintained (see transfer coordinates in FIG. 4). Thereby, since the void mixed in the sealing resin 17 can be crushed and molded, the molding quality can be improved. Therefore, a molded product having a very thin package thickness can be mass-produced at a low cost without using a new facility.

  Next, as shown in the right half view of FIG. 3, after the sealing resin 17 is heated and cured, the lower die 3 is slightly moved down (for example, 0.2 mm) while the clamper 6 clamps the workpiece W, thereby the cavity piece 5. Only the mold is moved to the retracted position to release the molded product. At this time, the upper and lower stopper blocks 9 and 16 are also slightly separated (for example, 0.2 mm). Thereby, the molded product can be easily separated from the mold without providing the mold 1 with a releasing means such as an ejector pin.

  Finally, as shown in the left half of FIG. 3, when the lower die 3 is further moved downward to open the die, the clamper 6 opens away from the workpiece W, and then the workpiece W is taken out from the lower die 3. The lower mold surface is cleaned as necessary, and one molding operation is completed.

Next, another example of the transfer molding method and the transfer molding apparatus will be described with reference to FIGS.
The same members as those in the first embodiment are denoted by the same reference numerals and the description is incorporated. Hereinafter, different configurations of the mold 1 will be described.
In the upper mold 2, a movable piston 18 is floatingly supported by a spring 19 with respect to the upper mold base block 4 on the surface of the clamper 6 facing the pot 14.

The right half of FIG. 5 raises the lower mold 3 to close the mold, and the work piece W is retracted by a predetermined thickness (for example, 0.2 mm) from the thickness dimension (for example, 0.3 mm) of the molded product. The state in which the predetermined first holding pressure (for example, 80 kgf / cm ² ) is maintained by clamping with the clamper 6 while maintaining the retracted position and further raising the plunger 15 to fill the cavity recess K with the molten resin. Shown (see FIG. 7, resin pressure, transfer coordinates, cavity depth).

The left half of FIG. 5 shows that the lower die 3 is further raised after resin filling, and the cavity piece 5 is further pushed into the cavity recess K to the molding position corresponding to the thickness dimension (for example, 0.3 mm) of the molded product. A state in which excess resin in the cavity recess K is pushed back from the gate to the pot 14 side is shown.
At this time, the surplus resin pushed back from the cavity recess K to the gate side when the cavity piece 5 is pushed from the retracted position to the molding position is retracted into the clamper 6 so that the movable piston 18 presses and shrinks the spring 19. To absorb. (See FIG. 7, movable piston position). At this time, the elastic force of the spring 19 needs to be set to be weaker than the elastic force of the spring (elastic member) that supports the plunger 15. Further, the elastic force of the spring 19 needs to be set to be weaker than the pressure applied when the second holding pressure (Pr2) applied by the plunger 15 is applied.

As shown in the left half of FIG. 6, the first pressure holding (e.g. 80 kgf / cm ²⁾ higher than the second pressure holding (e.g. 100 kgf / cm ²⁾ while maintaining the sealing resin plunger 15 is raised again 17 Is cured by heating for a predetermined time (cure). At this time, the movable piston 18 is pushed up to the maximum so that the second holding pressure (for example, 100 kgf / cm ² ) can be maintained. Further, the amount of sinking of the plunger 15 into the pot 14 with respect to the surplus resin is absorbed by the movable piston 18 to facilitate release from the pot 14 (see resin pressure, transfer coordinates, and movable piston position in FIG. 7).

  Next, in the right half of FIG. 6, after the sealing resin 17 is heated and cured, the lower mold 3 is moved slightly downward (for example, 0.2 mm) while the clamper 6 clamps the workpiece W, and only the cavity piece 5 is retracted. The molded product is released by moving to a position. At this time, the upper and lower stopper blocks 9 and 16 are also slightly separated (for example, 0.2 mm). Thereby, the molded product can be easily separated from the mold without providing the mold 1 with a releasing means such as an ejector pin. In addition, with the mold opening operation, the movable piston 18 returns to the position flush with the mold cull of the clamper 6 by the elastic force of the spring 19.

  Finally, when the lower mold 3 is further moved downward to open the mold, the clamper 6 is separated from the work W to open the mold, and then the work W is taken out from the lower mold 3 and the lower mold surface is moved as necessary. After being cleaned, one molding operation is completed.

Next, another example of the transfer molding method and the transfer molding apparatus will be described with reference to FIG.
The same members as those in the first embodiment are denoted by the same reference numerals and the description is incorporated. Hereinafter, different configurations of the mold 1 will be described.
In the upper mold 2, the cavity piece 5 is floatingly supported on the upper mold base block 4 by a suspension pin 20 and a spring 21. The cavity piece 5 is switched between a retracted position and a molding position by a wedge mechanism. The clamper 6 is fixed to the upper mold base block 4.

  Specifically, a wedge-shaped movable piece 22 is provided between the upper mold base block 4 and the cavity piece 5. Each of the contact surfaces of the movable piece 22 and the cavity piece 5 is similarly formed with a tapered surface 23 inclined in the height direction with respect to the horizontal plane. For example, when the movable piece 22 is moved from the outside to the inside, the cavity piece 5 is pushed downward, and when the movable piece 22 is moved from the inside to the outside, the cavity piece 5 is retracted upward. A screw shaft 25 connected to a motor shaft of a servomotor 24 that can be driven in forward and reverse rotation is screwed to the movable piece 22. The servo motor 24 is rotated in a predetermined direction to move the movable piece 22 forward and backward.

The right half of FIG. 8 raises the lower mold 3 to close the mold, and the work piece W is retracted by a predetermined thickness (for example, 0.2 mm) from the thickness dimension (for example, 0.3 mm) of the molded product. The state in which the predetermined first holding pressure (for example, 80 kgf / cm ² ) is maintained by clamping with the clamper 6 while maintaining the retracted position and further raising the plunger 15 to fill the cavity recess K with the molten resin. Show.

In the left half of FIG. 8, after filling the resin, the servo motor 24 is activated to move the movable piece 22 into the mold, and the cavity piece 5 is molded corresponding to the thickness dimension (eg, 0.3 mm) of the molded product. This shows a state where the resin is further pushed into the cavity recess K to the position and the excess resin in the cavity recess K is pushed back from the gate to the pot 14 side.
At this time, when the cavity piece 5 is pushed out from the retracted position to the molding position, the excess resin pushed back from the cavity concave portion K to the gate side is moved back into the pot 14 to absorb the excess resin.

The above-described transfer molding method and transfer molding apparatus have been described using an upper mold cavity and a lower mold pot arrangement type mold mold, but may be a lower mold cavity, or an upper mold pot and a lower mold cavity arrangement. It may be a mold.
Further, although the fixed mold is described as the upper mold 2 and the movable mold is the lower mold 3, the present invention is not limited to this, and the fixed mold may be the lower mold 3 and the movable mold may be the upper mold 2.
Moreover, although the Example which absorbs surplus resin by retreating in the pot 14 of the plunger 15 and the Example which absorbs surplus resin by retracting in the clamper 6 of the movable piston 18 were demonstrated, these were used together. Also good.
Further, as the workpiece W, in addition to a semiconductor chip mounted on a substrate, a light emitting element such as a white LED in which a phosphor is mixed into a sealing resin can be applied.

Next, another example of the transfer molding method and the transfer molding apparatus will be described with reference to FIGS. Since the configuration of the mold 1 is the same as that shown in FIG. 1, the description will be used, and the control system of the transfer molding apparatus will be mainly described.
In FIG. 9, the lower mold 3 is supported on the lower mold platen 26. The lower mold platen 26 is linked to a screw shaft 27b that is rotationally driven by a press drive motor (press drive source) 27, and is driven up and down by being guided by a guide post 28 by driving the press drive source 18 forward and reverse. The mold 1 is opened and closed. An upper mold platen 29 is connected to the guide post 28, and the upper mold 2 is supported by the upper mold platen 29.

  The lower platen 26 is provided with a transfer drive motor (transfer drive source) 30. The transfer drive motor 30 moves the plunger 15 that presses the sealing resin 17 from the pot 14 provided in the lower mold 3 toward the cavity recess K up and down. As the plunger 15, a multi-plunger supported by an equal pressure unit or the like is used.

  The motor shaft of the press drive motor 27 is provided with an encoder 27a (press coordinate detection means), and the press coordinate (Cp) is detected from the motor rotation amount. The motor shaft of the transfer drive motor 30 is provided with an encoder 30a (transfer coordinate detection means), and the transfer coordinate (Ct) is detected from the motor rotation amount. Further, a pressure sensor 31 (resin pressure detecting means) for detecting a pressure (Pt) acting on the transfer mechanism (particularly the plunger 15) is provided at the bottom of the plunger 15. Since this pressure (Pt) has a proportional relationship with the resin pressure (resin pressure; Pr) acting on the sealing resin 17, the resin pressure (Pt) can be detected from the detection signal of the pressure sensor 31. Further, the guide post 28 is provided with a detection unit 32 that detects a strain (εp) of the guide post 28 at the time of clamping. Since this strain (εp) has a proportional relationship with the mold clamp pressure (Pc), the mold clamp pressure (Pc) can be detected from the detection signal of the detection unit 32. That is, in this embodiment, control using the detection signal of the pressure (Pt) acting on the transfer mechanism as the resin pressure (Pt) and the detection signal of the strain (εp) as the mold clamping pressure (Pc) is possible. It has become. As an example of the detection unit 32, a strain gauge or the like that detects an increase / decrease in the mold clamp pressure by converting the increase / decrease in the guide post 28 is used.

  The detection signal from each detection unit described above is input to the control unit 33 (control unit). The control unit 33 outputs a control signal based on each detection signal described above to control the drive operation of the press drive motor 27 and the transfer drive motor 30. The cavity depth (Dc), which will be described later, basically refers to the height (interval) from the clamp surface of the clamper 6 to the end surface of the cavity piece 5, and after clamping as shown in FIG. Corresponds to the height of the end face of the cavity piece 5 and the workpiece (substrate) W.

A timer 34 is connected to the control unit 33. When the timer 34 notifies that a predetermined time has elapsed, the control unit 33 controls the drive operation of the press drive motor 27 or the transfer drive motor 30, respectively.
For example, in FIG. 10, the timer 34 measures a predetermined time (T1) from when the first press coordinate (Cp1) is detected until the transfer drive motor 30 is activated. Further, a predetermined time (T2) during which the resin pressure is maintained at the first holding pressure (Pr1) and a predetermined time (T3) during which the resin pressure is maintained at a lower intermediate holding pressure (Prt) are measured. In addition, the transfer drive source is restarted for a predetermined time (T4) after the press drive motor 27 is restarted and the final second press coordinate (Cp2) (or the third press coordinate (Cp3) before it) is detected. At least one elapsed time of the predetermined time (T5) during which the second holding pressure (Pr2) is maintained is measured and notified to the control unit 33.

Here, a transfer molding method using the transfer molding apparatus will be described with reference to FIGS. 1 to 3 based on the timing chart of FIG. As an example, the thickness of the molded product of the workpiece W is described as 0.3 mm from the substrate surface.
The press drive motor 27 is activated by a control signal from the control unit 33, and the mold is closed until the encoder 27a detects that the work W has reached the first press coordinate (Cp1) after being clamped by the clamper 6. . The cavity depth (Dc) is maintained at a predetermined value until the workpiece W is clamped by the clamper 6. When the controller 33 detects that the cavity depth (Dc) has reached the first press coordinate (Cp1) at which the first cavity depth (Dc1) reaches the first cavity depth (Dc1), the controller 33 stops driving the press drive motor 27. . In this case, the first press coordinate (Cp1) is the mold clamp pressure (Cp1) when the press coordinate (Cp) reaches the final second press coordinate (Cp2) described later, for example. The coordinates are set to be sufficiently lower than Pc2). The first press coordinate (Cp1) is preferably a coordinate that provides a mold clamp pressure (Pc) that allows air venting while preventing resin leakage, and the mold clamp pressure (Pc1) is the mold clamp pressure (Pc1). It can also be made very low with respect to Pc2) (for example, 1/10 or less). In this case, when the low-pressure clamp state is set, if the resin is not a resin having a low viscosity and a long gel time like a liquid resin but a resin having a high viscosity such as a tablet resin for transfer molding containing a filler, the clamped release film 10 is used. It is possible to prevent resin leakage while venting from a slight gap remaining between the workpiece W and the workpiece W. Further, when the mold clamping pressure (Pc) is extremely low (almost 0) and the clamping is hardly performed, the release film 10 is stretched over the upper mold 2 and the corners of the clamper 6 are formed in the entire outer periphery of the cavity recess K. Although it is stretched so as to follow the portion, in reality, the film is bent so as to swell slightly in the vicinity of the apex of the corner portion of the clamper 6 due to the elasticity of the film itself, and is separated from the clamper 6. Therefore, since the lower surface of the release film 10 abuts on the workpiece W in the vicinity of the apex of the corner and the gap between the clamper 6 and the workpiece W is sealed, it is possible to prevent resin leakage while air venting if the resin is highly viscous. Become.

  The right half view of FIG. 1 shows that the workpiece W is carried into the workpiece mounting portion 13a of the lower mold insert block 13, and the lower mold 3 in which the sealing resin (resin tablet) 17 is supplied to the pot 14 is raised and clamped. The temporary clamp state in which the clamper 6 with the release film 10 held by suction on the surface clamps the workpiece W is shown. At this time, the workpiece W is clamped by the clamper 6 by moving to the retreat position where the cavity piece 5 of the upper mold 2 is retracted by a predetermined thickness (for example, 0.2 mm) from the thickness dimension (for example, 0.3 mm) of the molded product. Yes. In other words, at this time, the workpiece W is clamped by the clamper 6 while the cavity piece 5 of the upper mold 2 is kept in the retracted position. Further, the upper stopper block 9 is stopped at a predetermined interval (0.2 mm) from the lower stopper block 16. At this time, the gap between the clamper 6 and the upper mold base block 4 is floatingly supported so as to have the same distance (0.2 mm).

  The control unit 33 activates the transfer drive motor 30 when the timer 34 measures the elapse of a predetermined time (T1) after the first press coordinate (Cp1) is detected.

As shown in the left half view of FIG. 1, the plunger 15 is lifted while the clamper 6 clamps the workpiece W, and the molten sealing resin 17 is filled into the cavity recess K through the die cull and runner gate. The control unit 33 monitors the transfer drive motor 30 with the signal of the encoder 30a so as not to reach the uppermost end position of the transfer mechanism, and sends a signal indicating that the resin pressure (Pr) has reached a predetermined first holding pressure (Pr1). When obtained from the pressure sensor 31, the transfer drive motor 30 is controlled so as to stop the raising of the plunger 15 and start the servo control (see transfer coordinates (Ct) in FIG. 10). Thereby, the transfer drive motor 30 is servo-controlled so that the resin pressure (Pr) becomes the predetermined first holding pressure (Pr1). In addition, at the time of all holding pressure control indicated by the wavy line in FIG. 10, the resin pressure (Pr) is maintained at a predetermined pressure by servo-controlling the transfer drive motor 30. After the resin filling (see the right half of FIG. 2), the control unit 33 determines that the resin pressure (Pr) detected by the pressure sensor 31 is the first holding pressure (Pr1; for example, 50 kgf / cm ² ) over a predetermined time (T2). Then, the transfer drive motor 30 is reversed. Subsequently, the control unit 33 starts servo control of the transfer drive motor 30 with a signal in which a predetermined intermediate holding pressure (Prt; for example, 30 kgf / cm ² ) lower than the first holding pressure (Pr1) is detected, and at the same time The timer 34 measures that the intermediate holding pressure (Prt) is maintained for a predetermined time (T3) (see FIG. 5 resin pressure (Pr)).

  Regarding the resin pressure (Pr) detected by the pressure sensor 31, the first holding pressure (Pr1) is maintained for a predetermined time (T2), and the intermediate holding pressure (Prt) lower than that is maintained for a predetermined time (T3). When detected, the control unit 33 restarts the press drive motor 27, moves the lower die 3 to the final second press coordinate (Cp2), and stops. Thereby, it will be in this clamp state. At this time, the mold clamping pressure (Pc) becomes a mold clamping pressure (Pc2) higher than the mold clamping pressure (Pc1), and the air vent is hardly performed, but the resin leakage can be surely prevented. Further, since the cavity piece 5 is pushed out from the retracted position to the molding position, it is allowed that the surplus resin in the cavity recess K is positively returned from the gate to the pot 14 side (see FIG. 10, transfer coordinates (Ct)).

  In the right half view of FIG. 2, after filling the resin, the cavity piece 5 is further pushed out to the molding position corresponding to the thickness dimension (eg, 0.3 mm) of the molded product, and the excess resin in the cavity recess K is removed from the gate to the pot 14 side. Push back. Specifically, as shown in the left half of FIG. 2, the lower die 3 is further raised, and the clamper 6 pushes and shrinks the spring 8 until it hits the upper die base block 4 and the upper and lower stopper blocks 9 and 16 hit. Clamp. At this time, the plunger 15 is retracted into the pot 14 while servo-controlling the speed of the plunger 15 so as to maintain the intermediate holding pressure (Prt), and the excess resin is absorbed.

  As a result, it is possible to easily fill the cavity recess K with the melted sealing resin 17 by enlarging the volume of the cavity recess K, thereby eliminating the unfilled region. In this case, as shown in FIG. 1, even if the workpiece W has a thin sealing thickness on the chip, the flow path of the sealing resin 17 can be extended to the entire cavity width including the upper surface of the chip. A thin package in which there are no 17 unfilled regions and fillers and phosphors are distributed without deviation in particle size can be mass-produced with an inexpensive resin. In addition, since the surplus resin is pushed back to the pot 14 after the predetermined intermediate holding pressure (Prt) lower than the first holding pressure (Pr1), the first holding pressure (Pr1) after the resin filling is maintained, so that the cavity Prevents resin leakage caused by an increase in the resin pressure inside, increases the resistance of the resin path, makes it difficult for excess resin to return from the gate to the pot side, increases the viscosity of the sealing resin, lowers the fluidity, and moldings Can prevent damage.

  Further, the control unit 33 detects the final second press coordinate (Cp2) at which the cavity depth (Dc) becomes the second cavity depth (Dc2) based on the signal of the encoder 27a, and then the timer 23 detects the predetermined time (T4). ) Is detected, the transfer drive motor 30 is restarted to push the plunger 15 to the second transfer coordinate (Ct2). As a result, the resin pressure (Pr) detected by the pressure sensor 31 is heated and pressurized while being maintained at a predetermined second holding pressure (Pr2) higher than the first holding pressure (Pr1) to be resin-sealed (FIG. 10). Resin pressure (see Pr)).

In the left half of FIG. 2, the first holding pressure by the plunger 14 is raised again by the transfer drive motor 20 maintained; (e.g. 100kgf / cm ² Pr2) (Pr1 e.g. 50 kgf / cm ²⁾ higher than the second pressure-holding The sealing resin 17 is heated and cured for a predetermined time (T5) as it is (see resin pressure (Pr) in FIG. 10).

In this way, after the clamper 6 clamps the workpiece W, the cavity piece 5 is pushed out into the cavity recess K by further mold closing operation, so that the thickness dimension (for example, 0.3 mm) of the target molded product is adjusted. The amount of resin can be adjusted (see cavity depth (Dc) in FIG. 10).
Thereby, since the void mixed in the sealing resin 17 can be crushed and molded, the molding quality can be improved. Therefore, a molded product having a very thin package thickness can be mass-produced at a low cost without using a new facility.

  Next, as shown in the right half of FIG. 3, after the sealing resin 17 is heated and cured, the press drive motor 27 is driven reversely while the clamper 6 clamps the workpiece W, so that the lower mold 3 is slightly (for example, 0. 0). 2 mm), the molded product is released from the mold by moving only the cavity piece 5 to the retracted position. At this time, the upper and lower stopper blocks 9 and 16 are also slightly separated (for example, 0.2 mm). Thereby, the molded product can be easily separated from the mold without providing the mold 1 with a releasing means such as an ejector pin.

  Finally, as shown in the left half view of FIG. 3, when the press drive motor 27 is driven in reverse to further move the lower die 3 downward to open the die, the clamper 6 opens away from the workpiece W, The workpiece W is taken out from the lower mold 3, the lower mold surface is cleaned as necessary, and one molding operation is completed.

  Further, in FIG. 10, the press drive motor 27 is moved from the final second press coordinate (Cp2) while maintaining the intermediate pressure (Prt) lower than the first pressure (Pr1) after the resin filling. By driving to the third press coordinate (Cp3) on the near side, it is possible to allow the excess resin in the cavity recess K to return from the gate to the pot 15 side. In this case, the cavity depth (Dc) is the third cavity depth (Dc3) deeper than the second cavity depth (Dc2). The mold clamp pressure (Pc) is a mold clamp pressure (Pc3) higher than the mold clamp pressure (Pc1). As a result, although the air vent is hardly performed as in the case of setting the mold clamping pressure (Pc2), the mold mold 1 has a clamping force increased by the elastic force of the spring 8 that presses the clamper 6. There is no risk. The third press coordinate (Cp3) can be arbitrarily set by the drive control of the press drive motor 27. However, at least before the upper and lower stopper blocks 9 and 16 abut, the work W is clamped by the clamper 6 and the resin does not leak. The coordinate position needs to obtain a sufficient clamping force. In the case of such molding, the spring 8 may be strengthened according to the flow viscosity of the sealing resin 17. For example, when the flow viscosity is small, the resin spring can be surely prevented by using the strong spring 8. The third press coordinate (Cp3) is higher than the pressure (resin pressure) applied by the plunger 15 when the pressure applied to the cavity piece 5 (mold clamping pressure) is applied to the second holding pressure. Is set.

In this state, the transfer drive motor 30 is started and the plunger 15 is pushed until the third transfer coordinate (Ct3) higher than the second transfer coordinate (Ct2) is detected by the pressure sensor 31. The sealing resin 17 is heated and cured while the resin pressure (Pr) is maintained at a predetermined second holding pressure (Pr2) higher than the first holding pressure (Pr1). At this time, since the cavity depth (Dc) is an arbitrary third cavity depth (Dc3) deeper than the second cavity depth Dc2, the thickness dimension of the package portion of the molded product is set as described above. It can be molded with any desired thickness within a range that is thicker than the case.
Although the control unit 33 controls the driving of the press drive motor 27 and the transfer drive motor 30 based on the measurement of the timer 34, a series of control operations may be performed by sequence control without using the timer 34. . In addition, the configuration in which the next operation is performed after the lapse of each predetermined time T1 to T5 has been described. May be performed immediately.

As described above, the excess resin in the cavity recess is removed from the gate by driving the press drive source to the final second press coordinate while maintaining the intermediate pressure lower than the first holding pressure after the resin filling. The sealing resin is allowed to return to the pot side, and the resin pressure detected by restarting the transfer drive source and pushing the plunger is maintained at a predetermined second holding pressure higher than the first holding pressure. By heat-curing, a thin package having no uneven distribution of filler diameter and phosphor diameter and no resin-filled region can be mass-produced using an inexpensive resin.
In addition, the press drive source is driven to the third press coordinate before the final second press coordinate while the resin pressure after the resin filling is maintained at the intermediate hold pressure lower than the first hold pressure, thereby surplus in the cavity recess The resin is allowed to return from the gate to the pot side, and the resin pressure detected by restarting the transfer drive source and pushing the plunger is increased and maintained at a predetermined second holding pressure higher than the first holding pressure. By heating and curing the sealing resin as it is, the thickness dimension of the package part can be molded as intended.

The above-described transfer molding method and transfer molding apparatus have been described using an upper mold cavity and a lower mold pot arrangement type mold mold, but may be a lower mold cavity, or an upper mold pot and a lower mold cavity arrangement. It may be a mold.
Further, although the fixed mold is described as the upper mold 2 and the movable mold is the lower mold 3, the present invention is not limited to this, and the fixed mold may be the lower mold 3 and the movable mold may be the upper mold 2.
Further, the present invention can be applied not only to products for single-sided molding but also to products for double-sided molding. For example, a structure for adjusting the depth of the cavity recess by a clamper using a spring can be provided in one mold, and a configuration for adjusting the depth of the cavity recess by a wedge mechanism can be provided in the other mold. In this case, by performing double-sided molding using the method according to the present invention, even a thin substrate can be sealed very thin without warping. Further, it is possible to control the order in which the cavity resin is filled first from the upper and lower cavity recesses, or to control the filling timing of the sealing resin 17 and the timing of returning the surplus resin. The upper mold 2 and the lower mold 3 may be driven by the same drive source without using the upper mold 2 and the lower mold 3 as separate drives.
Further, as the workpiece W, in addition to a semiconductor chip mounted on a substrate, a light emitting element such as a white LED in which a phosphor is mixed into a sealing resin can be applied.

  In the transfer molding apparatus described above, the configuration example using the upper mold 2 that clamps the workpiece W and includes the clamper 6 having the mold cull and the mold runner gate formed at the center has been described. It is not limited to. For example, a clamper that clamps the workpiece W around the cavity piece 5 and a center block in which a mold cull and a mold runner gate are arranged to face the pot are separated from each other and supported by being suspended via springs 8. The upper mold 2 can also be used. Also, in the transfer molding apparatus shown in FIG. 8, the clamper 6 may be floatingly supported by the spring 8 to control the mold clamping pressure as shown in FIG.

W Work
K cavity recess 1 mold mold
2 Upper mold
3 Lower mold
4 Upper mold base block
5 Cavity piece
6 Clamper
8, 19, 21 Spring
9 Upper stopper block
10 Release film
11 Lower mold base block
12 Lower chase block
13 Lower insert block
14 pots
15 Plunger
16 Lower stopper block
17 Sealing resin
18 Movable piston
20 Hanging pin
22 Movable piece
23 Tapered surface
24 Servo motor
25, 27b Screw shaft
26 Lower platen
27 Press drive motor 27a, 30a Encoder
28 Guide post
29 Upper platen
30 Transfer drive motor
31 Pressure sensor
32 detector
33 Control unit
34 Timer

Claims (13)

This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
In the step of pushing back the surplus resin from the gate to the pot side, the surplus resin is pushed back while maintaining an intermediate holding pressure lower than the first holding pressure. This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
A transfer molding method comprising a step of releasing a molded product by moving only a cavity piece to a retracted position while a clamper clamps a workpiece after heat-curing the sealing resin . This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
The transfer molding method, wherein the clamper is floatingly supported by a base block, the cavity piece is fixed to the base block, and after the clamper clamps a workpiece, the cavity piece is pushed out by a further mold closing operation . This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
The transfer molding method, wherein the clamper is fixed to a base block, the cavity piece is floatingly supported by the base block, and the cavity piece is switched between a retracted position and a molding position by a wedge mechanism . This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
A transfer molding method characterized in that, when the cavity piece is pushed out from the retracted position to the molding position, excess resin pushed back from the cavity concave portion to the gate side is absorbed by retreating the plunger into the pot . This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
A movable piston is supported in a floating manner on the mold cull forming surface of the clamper, and when the cavity piece is pushed from the retracted position to the molding position, excess resin pushed back from the cavity recess to the gate side is transferred to the movable piston. A transfer molding method comprising absorbing by retreat . The clamper clamps the work by driving the press drive source for opening and closing the mold to a predetermined first press coordinate, and the plunger is operated by the transfer drive source to fill the cavity recess with the molten resin. By maintaining the first holding pressure and lowering the resin pressure after filling the resin to an intermediate holding pressure lower than the first holding pressure, the press drive source is driven to the final second press coordinate, Allow the surplus resin to return from the gate to the pot side, and actuate the plunger again to heat and cure the sealing resin while maintaining the resin pressure at a predetermined second holding pressure higher than the first holding pressure. The transfer molding method according to any one of claims 1 to 6. This is a transfer molding method using a mold in which a cavity recess is formed by a cavity piece forming a cavity bottom and a clamper disposed so as to surround the cavity, and a release film is stretched on a mold surface including the cavity recess. And
The workpiece carried into the mold is moved to a retracted position where the cavity piece is retracted by a predetermined thickness from the thickness dimension of the molded product, and clamped by the clamper;
Maintaining the predetermined first holding pressure by operating the plunger while the clamper clamps the workpiece to fill the cavity with the molten resin;
After resin filling, a step of further extruding the cavity piece to a molding position corresponding to the thickness dimension of the molded product and pushing back excess resin in the cavity recess from the gate to the pot side;
Including the step of heat-curing the sealing resin while maintaining the second holding pressure higher than the first holding pressure by operating the plunger again.
The clamper clamps the work by driving the press drive source for opening and closing the mold to a predetermined first press coordinate, and the plunger is operated by the transfer drive source to fill the cavity recess with the molten resin. The press drive source is driven to the third press coordinate before the final second press coordinate while maintaining the first holding pressure and lowering the resin pressure after filling the resin to an intermediate holding pressure lower than the first holding pressure. Thus, the excess resin in the cavity recess is allowed to return from the gate to the pot side, the plunger is operated again, and the resin pressure is maintained at a predetermined third holding pressure higher than the first holding pressure. A transfer molding method characterized by heat-curing a sealing resin . A cavity mold is formed by a cavity piece that forms a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface that includes the cavity depression, and
A press drive source for opening and closing the mold,
Press coordinate detection means for detecting press coordinates from the drive amount of the press drive source;
A transfer drive source for driving a plunger for pressure-feeding a sealing resin from a pot provided in the mold to the cavity recess;
A resin pressure detecting means for detecting a resin pressure acting on the plunger;
Control means for controlling drive operations of the press drive source and the transfer drive source,
A predetermined time from when the first press coordinate is detected to when the transfer driving source is activated, a predetermined time during which the resin pressure is maintained at the first holding pressure, and a predetermined holding at an intermediate holding pressure lower than the first holding pressure. The transfer drive source is restarted for a predetermined time after the press drive source is restarted and the final second press coordinate or the third press coordinate before it is detected until the transfer drive source is restarted. And a timer for detecting at least one elapsed time of a predetermined time during which the second holding pressure is maintained,
When the timer informs that a predetermined time has elapsed, a press driving source is activated by the control means, and the mold is closed until reaching a first press coordinate at which a workpiece is clamped by a clamper, and the press coordinate detecting means With the first press coordinates detected and the press drive source stopped, the transfer drive source is activated and the sealing resin is pumped into the cavity recess, and the resin pressure detected by the resin pressure detecting means is When the first holding pressure and a predetermined intermediate holding pressure lower than the first holding pressure are detected for a predetermined time, the control means drives the press drive source to the final second press coordinate or the third press coordinate before it, Allowing excess resin in the cavity recess to return from the gate to the pot side, restarting the transfer drive source and pushing the plunger Transfer molding apparatus characterized by the resin pressure detected by Rukoto is locked heated pressurized by resin molding while keeping the second pressure holding predetermined higher than the first pressure-holding. A cavity mold is formed by a cavity piece that forms a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface that includes the cavity depression, and
A press drive source for opening and closing the mold,
Press coordinate detection means for detecting press coordinates from the drive amount of the press drive source;
A transfer drive source for driving a plunger for pressure-feeding a sealing resin from a pot provided in the mold to the cavity recess;
A resin pressure detecting means for detecting a resin pressure acting on the plunger;
Control means for controlling the drive operation of the press drive source and the transfer drive source, respectively,
The clamper is floatingly supported by a base block, the cavity piece is fixed to the base block, and after the clamper clamps a workpiece, the cavity piece is pushed out by further mold closing operation by the press drive source. The transfer molding device characterized by this. A cavity mold is formed by a cavity piece that forms a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface that includes the cavity depression, and
A press drive source for opening and closing the mold,
Press coordinate detection means for detecting press coordinates from the drive amount of the press drive source;
A transfer drive source for driving a plunger for pressure-feeding a sealing resin from a pot provided in the mold to the cavity recess;
A resin pressure detecting means for detecting a resin pressure acting on the plunger;
Control means for controlling the drive operation of the press drive source and the transfer drive source, respectively,
The transfer molding apparatus according to claim 1, wherein the clamper is fixed to a base block, the cavity piece is floatingly supported by the base block, and the cavity piece is switched between a retracted position and a molding position by a wedge mechanism. A cavity mold is formed by a cavity piece that forms a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface that includes the cavity depression, and
A press drive source for opening and closing the mold,
Press coordinate detection means for detecting press coordinates from the drive amount of the press drive source;
A transfer drive source for driving a plunger for pressure-feeding a sealing resin from a pot provided in the mold to the cavity recess;
A resin pressure detecting means for detecting a resin pressure acting on the plunger;
Control means for controlling the drive operation of the press drive source and the transfer drive source, respectively,
A transfer molding apparatus that absorbs surplus resin pushed back from the cavity recess to the gate side when the cavity piece is pushed from the retracted position to the molding position by retreating the plunger into the pot. A cavity mold is formed by a cavity piece that forms a cavity bottom and a clamper disposed so as to surround the cavity piece, and a release film is stretched on a mold surface that includes the cavity depression, and
A press drive source for opening and closing the mold,
Press coordinate detection means for detecting press coordinates from the drive amount of the press drive source;
A transfer drive source for driving a plunger for pressure-feeding a sealing resin from a pot provided in the mold to the cavity recess;
A resin pressure detecting means for detecting a resin pressure acting on the plunger;
Control means for controlling the drive operation of the press drive source and the transfer drive source, respectively,
A movable piston is supported in a floating manner on the mold cull forming surface of the clamper, and when the cavity piece is pushed from the retracted position to the molding position, excess resin pushed back from the cavity recess to the gate side is transferred to the movable piston. A transfer molding device that absorbs by retreating.

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