JPS6233317Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a molding apparatus for resin-encapsulating semiconductor elements.

2. Description of the Related Art Conventionally, a so-called transfer molding apparatus has been used as an apparatus for resin-encapsulating semiconductor elements. For example, as shown in FIG. 1, this device is fixedly installed below a fixed platen 2 fixed to the upper end of a device frame 1 via a heat insulating plate 3, an upper mold space block 4, and an upper mold plate 5. A heat insulating plate 9 and a lower mold mounting plate 10 are mounted on the upper part of a movable platen 8 which is configured to be movable up and down by a fixed upper mold 6 and a vertical movement mechanism 7 using hydraulic pressure etc. provided at the lower part of the device frame 1.・Movable lower mold 1 fixed via lower mold space block 11 and lower mold plate 12
3, and a large cylindrical pot 14 is vertically provided in the center of the upper mold 6 side for charging a molding material such as silicone resin or epoxy resin. A transfer cylinder 16 equipped with a plunger 15 for pressurizing the molding material to be inserted into the pot 14 is arranged on the upper surface side, and the upper mold space block 4 connects the fixed platen 2 and the upper mold plate 5. The space with the required interval between the pots is provided as a material input space 17 required for an operator to input molding material into the pot 14 from the upper end opening, and is A plurality of upper mold cavities 18 for molding the upper half of the resin molded body are disposed on the mold surface. Furthermore, on the mold surface on the lower mold 13 side, there is a pot 14 on the upper mold side.
A curl 19 is provided at a position corresponding to the position of
In addition, lower mold cavities 20 for molding the lower half of the resin molded body are disposed at positions corresponding to the upper mold cavities 18 to face each other, and the curls 19 and the lower mold cavities 20 are made of molten resin material. The runners 21 and the lower die cavity 20 are communicated with each other via a runner 21 that serves as a transfer route and a gate 22 that connects the runner and the lower mold cavity 20. Furthermore, in the space 17 formed by the upper mold space block 4 and the space 23 constituted by the lower mold space block 11, there are an upper mold cavity 18 and a lower mold cavity 20.
Ejector pin 2 for pushing out the upper and lower half resin molded bodies molded in
Ejector plate 26,2 with 4,25
7 are arranged respectively. That is, on the upper ejector plate 26 side, there are a spring 28 for pushing down the plate and a return pin 2 for pushing up the plate.
9 is provided, and the elasticity of the spring 28 acts to push down the upper ejector pin 24 and push the resin-molded upper half inside the upper mold cavity 18 downward when the mold is opened, and also acts to push the upper half of the resin molded body in the upper mold cavity 18 downward. During mold clamping, the pin 29 moves the upper ejector plate 26 upward in response to the upward force of a return pin provided on the lower ejector plate 27 side, which will be described later. Mold cavity 18
It is configured to be pushed up to the position of the inner bottom surface of. Further, on the lower ejector plate 27 side, there are lower ejector pins 30 for pushing out the cured resin remaining in the curl 19 upward after the mold is opened, and a number of lower ejector pins 30 are provided at predetermined positions between the upper and lower molds 6 and 13. A push-up pin 31 for pushing up a loading frame (not shown) for attaching and detaching a book lead frame, and a spring 32 for pushing down the lower ejector plate 27 are provided. When the plate 27 is pushed down, the upper end surfaces of the lower ejector pins 25 and 30 on the plate are pushed down to the positions of the inner bottom surfaces of the lower die cavity 20 and the curl 19, respectively. Further, an ejector bar 34 is disposed below the lower ejector plate 27 and is movable up and down through a vertical through hole 33 formed in communication with the movable platen 8, the heat insulating plate 9, and the lower die mounting plate 10. Therefore, after opening the mold, by moving the ejector bar 34 upward to push up the lower ejector plate 27, the ejector pins 25, 30 are curled with the resin molded lower half in the lower mold cavity 20. 19. The hardened resin remaining in the runner 21 and gate 22 is pushed out at the same time, and the push-up pin 31 simultaneously pushes up the aforementioned loading frame, so remove the loading frame from between the upper and lower molds 6 and 13. This makes it possible to take out the lead frame after resin molding. In addition, a lower return pin 35 is provided at a position corresponding to the upper return pin 29 on the upper ejector plate 26, and the return pin 35 is used when the mold is clamped.
The upper ejector plate 26 is configured to be pushed up to the above-mentioned position via the upper return pin 29. Further, both upper and lower molds 6, 13 are provided between the upper mold plate 5 and the lower mold plate 12.
A guide pin 36 and a guide bush 37 are provided for positioning during mold clamping.

When performing resin molding using the conventional apparatus as described above, both the upper and lower molds 6, 13 are heated to a predetermined temperature in advance, and the semiconductor element is mounted at a predetermined position between the two molds via a loading frame. A large number of lead frames are each set, and the molds are clamped in this state. Next, the operator normally measures the required amount of molding material into the input space 17.
The water is then artificially injected directly into the pot 14. Next, when the plunger 15 is inserted into the pot 14 and pressurizes the molding material, the material is compressed into both molds 6,
The molten resin is melted by the heat from the resin 13 and the pressure applied by the plunger 15, and the molten resin is injected under pressure into the upper and lower cavities 18 and 20 through the curl 19, runner 21 and gate 22.
The semiconductor element on the lead frame within the cavity is encapsulated in a resin molded body which is molded into a desired shape by the cavities 18 and 20. After the resin molding described above, when the mold is opened, the resin molded product is automatically pushed out from the upper and lower cavities 18, 20 by the upper and lower ejector pins 24, 25 as described above. , as shown in FIG.
Residual hardened resin 40, residual hardened resin 41 on the runner 21, and residual hardened resin 42 on the gate 22 are integrally connected.
Therefore, in such a conventional device, the amount of the residual cured resins 40, 41, and 42, which are unnecessary parts, is inevitably generated in a large amount due to its configuration, and furthermore, this type of molding material is a thermosetting resin. As a result, it has the disadvantage of not being able to be recycled and resulting in a significant drop in the effective utilization rate of the material, which is a serious drawback that goes against recent social demands for resource conservation and safe waste disposal. It is said that Also, for example,
In the arrangement positional relationship between the curl 19 and the upper and lower cavities 18, 20, when comparing the resin molding state in the cavity closest to the curl 19 side and the cavity located further away, it is found that the runner has a long molten resin. Due to the fact that the curing reaction is accelerated when the curl 21 is transferred, the viscosity of the resin differs when the resin is injected into each cavity. In the cavity where the resin is pressurized and injected into the cavity through the gate 20, the viscosity of the resin increases, resulting in an insufficient amount of resin injection, resulting in defective molded products due to insufficient filling, or the contact between the semiconductor element and the leads. Deforming or cutting the wires that electrically connect the wires can cause serious harm. Furthermore,
In the conventional device described above, since the pot 14 is provided on the upper mold 6 side due to its configuration, the elongated transfer cylinder 16 must be disposed on the upper surface of the upper fixed platen 2 in the vertical direction. , this means that the overall height of the device becomes significantly longer.
Therefore, when moving or installing the equipment, it is necessary to remove the transfer cylinder 16 part due to various height restrictions such as the height of the entrance to the factory or the low ceiling height of the installation location. In such a case, it becomes extremely difficult to restore accuracy when reassembling the device. In addition, in order to secure the space 17 for charging the molding material and to prevent danger to the worker, it is necessary to move the plunger 15 up to near the top surface of the fixed platen 2 when charging the molding material. However, from the perspective of the molding operation, the plunger 15 has to be pulled out from the pot 14 every molding cycle, and therefore the temperature of the plunger becomes uneven, which adversely affects the heating effect of the molding material. Since this has the disadvantage of reducing molding efficiency, it has been necessary to incorporate a dedicated heater 43 into the conventional plunger 15 to keep the temperature constant.

In this invention, a transfer cylinder for pressurized injection of resin molding material is provided on the mold clamping part side of a movable lower mold placed opposite to a fixed upper mold, and a pot for introducing resin molding material is placed on the movable lower mold side. At the same time, a plunger for pressurizing the molding material is inserted into the pot so that it is always in a fitted state, so that the plunger always receives heat from the lower mold side, and a plunger for fixing the upper mold is configured. A molding device for resin encapsulation molding of semiconductors characterized by having an ejector mechanism for resin molded products disposed on the upper fixed plate side, the purpose of which is to significantly reduce the overall height of the molding device. In addition, the heating effect of the molding material is stabilized without the need for a heater dedicated to the plunger, and excellent resin molded products with consistent quality can be obtained.Furthermore, the mold removal time can be adjusted, making removal work easier. It is an object of the present invention to provide a molding device for semiconductor resin encapsulation molding, which can prevent danger and improve work efficiency.

Hereinafter, the molding apparatus of the present invention will be explained based on the embodiment diagrams shown in FIGS. 2 to 4 and 6.

The device of the present invention has a fixed upper mold 106 disposed below a fixed plate 102 fixed to the upper end of the device frame 101, and can be moved up and down by a vertical movement mechanism 107 provided at the bottom of the device frame 101. It has a configuration of a type of transfer molding device in which a movable lower mold 113 is disposed above the configured movable platen 108. The fixed upper mold 106 described above is fixedly installed below the fixed platen 102 via a heat insulating plate (not shown), upper mold space block 104 and upper mold plate 105, and the movable lower mold 113 is fixed to the lower part of the movable platen 108. It is fixed to the upper part via a heat insulating plate 109, a lower mold space block 111, and a lower mold plate 112. In addition, the upper space block 1
04, and space 1 formed by the lower mold space block 111.
23 includes an ejector plate 126 equipped with ejector pins 124 and 125 for pushing out the upper and lower half resin molded bodies formed in the upper mold cavity 118 and the lower mold cavity 120, 127 are arranged respectively. On the upper ejector plate 126 side, there is a spring 145 for pushing up the plate, an upper return pin 129 for pushing down the lower ejector plate 127, which will be described later, during mold clamping, and a hardened resin remaining in the curl 119. An ejector pin 130 for pushing downward is provided, and the elasticity of the spring 145 is such that when the mold is clamped, the upper ejector pins 124 and 130
The lower end surface of the upper mold cavity 118 and the curl 11
It acts to push it up to the position of the inner bottom surface of No.9. In addition, an upper ejector mechanism 146 to be described later
When the oil piston rod 147 is moved down at a predetermined time, the upper ejector plate 12
6 is configured to be forcibly pushed down against the upward force of the spring 145. Further, on the lower ejector plate 127 side, a lower return pin 13 is provided at a position corresponding to the return pin 129 on the upper ejector plate 126.
5 is provided on the lower surface of the lower ejector plate 127, and a spring 148 is provided on the lower surface of the lower ejector plate 127 to push up the plate when the mold is opened, and the spring contacts the upper return pin 129 when the mold is closed. It is compressed downward by the lower ejector plate 127 which is moved downward via the corresponding lower return pin 135, and at this time, the upper end surface of the lower ejector pin 125 is pushed down to the position of the inner bottom surface of the lower mold cavity 120. It is configured so that Further, a guide pin 136 and a guide bush 137 are provided between the upper mold plate 105 and the lower mold plate 112 for positioning when the upper and lower molds 106, 113 are clamped. In addition, the reference numeral 144 in the figure
The fixed plate 102 and the upper ejector plate 1
26.

Next, various points in which the configuration of the embodiment of the present invention is significantly different from those of conventional devices will be explained.

That is, a required plurality of pots 114 for charging resin molding material are provided at predetermined positions of a movable lower mold 113 disposed opposite to a fixed upper mold 106, and plungers 115 for pressurizing the molding material are respectively installed in the pots. A cavity 1 is always disposed in a fitted state and is disposed facing between the pot 114 and the upper and lower molds 106 and 113.
18, 120 and curl 119 and gate 122
This is a point where communication is formed only by

Further, an upper ejector mechanism using hydraulic pressure or the like is provided on the fixed plate 102 side fixed to the upper end of the device frame 101, and is configured to be able to adjust and control the timing of pushing down the upper ejector pin 124 with respect to the resin molded body. 146 is arranged.

In addition, the injection of the molding material into the pot 114 is as follows:
After opening the mold, the parting line for both molds (P.
Since it is possible to do this from the L) side, there is a dedicated loading space 17 in the conventional device (Fig. 1).
Furthermore, since the pot 114 and the plunger 115 are arranged on the movable lower mold 113 side, the overall height of the device of the present invention is at least as large as the space 17 and the length of the upper transfer cylinder 16 in the conventional device. The point is that it is configured so that it is lowered by a certain amount.

In addition, the plunger 115 is moved upward in order to prevent danger to the worker, and pressurizes the molding material in the pot 14, as shown in FIG. However, as shown in FIG. 2, the upward movement is performed only to pressurize the molding material in the pot 114. Since the vertical movement is performed over a short distance of ₁ minute, a small lower transfer cylinder 116 necessary for vertically moving the plunger 115 is disposed below the movable plate 108.

Further, the plunger 115 is connected to the pot 114.
Since the plunger is always fitted inside and constantly receives heat from the lower mold 113 side, there is no built-in heater dedicated to heating the plunger to a constant temperature.

In addition, as shown in FIG. 3, both upper and lower molds 106,
Pallet 150 for taking out the molded product 149 between 113 and 113
The point is that it is arranged so that it can move forward and backward.

In addition, the pot 114 and the plunger 115
Basically, the same number of cavities are provided (in the example shown, two sets of cavities 118 and 120 are provided for one set of pot 114 and plunger 115). )
Therefore, the sizes of the individual pots 114, the plungers 115, and the curls 119 provided on the upper die 106 can be significantly reduced in size.

In the above configuration, in order to perform resin encapsulation molding of a semiconductor element, both molds 106 and 113 that have been heated to a predetermined temperature are opened, and then a lead with a semiconductor element attached to a predetermined position between the two molds is opened. The frames are set appropriately, and the molding materials are poured into the pots 114 from the parting line (PL) surface and the molds are clamped.

Next, when the plunger 115 is moved upward to pressurize the molding materials in the pots 114, each of the molding materials is melted by the heat from both molds 106, 113 and the pressing force by the plunger 115, and The molten resin is curl 119 and gate 1
Upper and lower cavities 1 communicated only through 22
Since the resin is injected under pressure into the cavities 18 and 120, the semiconductor element on the lead frame within the cavity is encapsulated in a resin molded body which is molded into a desired shape by the cavity.

Next, when the mold is opened, the lower ejector pin 125 moves upward due to the elasticity of the lower spring 148 as the lower mold 113 side moves downward, and the resin molded body is removed from the lower mold cavity 120 and gate 122. Push upwards. However, at this time, the upper ejector plate 126 provided on the side of the fixed upper mold 106 is pushed up by the elasticity of the spring 145, and therefore the resin molded body is pushed up into the upper mold cavity 118 and the curl 119. It remains fitted and fixed.

Next, in the above state, as shown in Figure 3,
When the pallet 150 is inserted below the upper mold 106 and the upper ejector mechanism 146 is activated to move its oil piston rod 147 downward, the upper ejector plate 126 is pushed down against the elasticity of the spring 145. , the ejector pins 124 and 130 are the molded product 14
9 onto the pallet 150 below, which is then retracted and the molded article 14
9 can be taken out.

As shown in FIG. 6, the molded product 149 taken out includes a resin molded body 139 encapsulating a lead frame 138 and a semiconductor element, and a hardened resin 1 remaining in the curl 119 and the gate 122.
40 and 142 are integrally connected. Therefore, in the embodiment of the present invention, the above-mentioned residual cured resins 140 and 142 are generated as unnecessary parts, but the total amount generated is determined by the shape of the curl 119 and the gate 122 having the minimum required size. The amount is extremely small because it is made up of Moreover, since the molten resin injected into the cavities 118 and 120 under pressure is immediately transferred through the curl 119 and the gate 122, the molten resin is injected under pressure into the cavities 118 and 120, respectively. All conditions are equal.

As described above, the device shown in the embodiment of the present invention is
Since there is no need to construct a runner for the transfer path of the molten resin, the effective utilization rate of the molding material is significantly improved, which can greatly contribute to the recent social demands such as resource conservation, and it also maintains a certain level of quality. It is possible to provide a molding apparatus that can simultaneously produce large quantities of resin molded products and is optimal for highly efficient production.

The device of this invention can omit the space for inputting the molding material, which was indispensable in conventional devices, and also eliminates the space for installing the transfer cylinder for the plunger on the top side of the molding device. As a result, the overall height of the molding device can be configured to be significantly lower than that of conventional devices, making it easier to handle the device and making it easier to charge the molding material into the pot. Since the work can be done from the parting line surface, the work space for the worker can be reduced and work efficiency can be improved.

In addition, a pot for introducing resin molding material is provided on the movable lower mold side, and a plunger for pressurizing the molding material is inserted into the pot so that it is always in a fitted state, so that the plunger heats the mold from the lower mold side. Since it was configured so that it always receives
This prevents the temperature of the plunger from becoming uneven due to the plunger being pulled out of the pot every molding cycle. Therefore, the heating effect of the molding material is stabilized without the need for a dedicated heater for the plunger, resulting in consistent quality. A resin molded product having the following properties can be obtained.

Furthermore, an ejector mechanism for the resin molded product is installed on the upper fixed platen side to fix the upper mold.
It is possible to use hydraulic pressure, etc. that is configured to adjust and control the timing of pushing down the upper ejector pin against the resin molded body, and therefore, when opening the mold, the upper ejector pin is pushed up. By keeping the resin molded body in the upper mold cavity,
As a result, it becomes possible to adjust the timing of mold removal, which brings about remarkable effects such as eliminating the danger of the work and improving work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing a conventional molding apparatus, and FIG. 5 is a front view and a plan view of a molded product molded by the apparatus. Figures 2 to 4
The figures show an embodiment of the device of the present invention; FIG. 2 is a partially cutaway front view of the device, FIG. 3 is a partially cutaway front view showing the device in the mold opening and molded product removal state, and FIG. 4 is a partially cutaway front view of the device.
The figure is a partially cutaway perspective view showing essential parts of both the upper and lower molds of the apparatus, and FIG. 6 is a front view and a plan view of a molded product molded by the apparatus. 101...Device frame, 102...Fixed plate,
106... Upper die, 113... Lower die, 114... Pot, 115... Plunger, 118... Upper die cavity, 119... Curl, 120... Lower die cavity, 122... Gate, 146... Ejector. Mechanism, 149... Molded product, 150... Palette.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A transfer cylinder for pressurized injection of resin molding material is provided on the mold clamping side of a movable lower mold placed opposite to a fixed upper mold, and a pot for introducing the resin molding material is provided. It is arranged on the movable lower mold side, and a plunger for pressurizing the molding material is inserted into the pot so as to be always in a fitted state so that the plunger always receives heat from the lower mold side, and further,
A molding device for semiconductor resin encapsulation molding, characterized in that an ejector mechanism for resin molded products is disposed on the upper fixed plate side for fixing the upper mold. (2) A molding device for semiconductor resin encapsulation molding according to claim (1) of the utility model registration claim, characterized in that a pallet for taking out resin molded products is arranged so as to be able to move forward and backward between the upper and lower molds.