JPH09252017A - Method for molding resin sealing of electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent voids produced in a molded resin sealing of an electronic component. SOLUTION: A resin tablet 113 at the room temperature, which is not subject to preliminary heating, is provided in a pot 108 and is expanded by heating under a reduced pressure. The moving speed (upward moving speed) of plungers 114 during resin pressurization is set lower than a predetermined speed during a part 152 of the stroke in which the expansion by heat of the room-temperature resin tablet 113 provided in the pot 108 is terminated. The air and moisture in a space 140 cut off from the outside air, the air and moisture discharged and released from the inside of the room-temperature resin table 113 during its expansion by heating, and the gases evolved during the heating of the room/ temperature resin table 113 are all efficiently and forcefully ejected by suction to the outside of the moulds (upper and lower moulds 101 and 102).

Description

Detailed Description of the Invention

[0001]

The present invention relates to, for example, ICs, LSs
The present invention relates to an improvement in a method for sealing and molding electronic components such as I, diodes, and capacitors with a resin, and in particular, formation of voids (air bubbles) inside and outside a resin-sealed molded body (mold package) of electronic components. Regarding things to prevent.

[0002]

2. Description of the Related Art Conventionally, resin molding of electronic parts has been carried out by a transfer molding method. In this method, for example, a resin molding die as shown in FIGS. , Usually as follows. In advance, the upper mold 1 and the lower mold 2 are heated to the resin molding temperature by the heating means 3. Next, the lead frame 5 on which the electronic component 4 is mounted is fitted and set in a predetermined position of the setting recess 6 provided on the mold surface of the lower mold 2, and the resin tablet 7 is supplied into the pot 8. Next, the lower mold 2 is moved upward, and the upper and lower molds (1, 2) are clamped as shown in FIG. At this time, the electronic component 4 and the lead frame 5 around the electronic component 4 are fitted in the cavities 9 opposite to the mold surfaces of the molds (1, 2). Further, since the resin tablets 7 in the pot 8 are heated and sequentially melted, when the resin tablets 7 are pressed by the plunger 10, the molten resin material is provided between the pot 8 and the cavity 9. The resin is transferred to both cavities 9 side through the resin flow path 11 and is injected / filled in the cavities 9. In addition,
Since the inside of the cavity 9 and the outside of the cavity are normally communicated with each other through an air vent formed by a narrow and shallow groove-shaped minute gap, a molten resin material is injected into both the cavities 9. At the time of filling, the residual air in the cavity 9 is naturally pushed out to the outside through the air vent by utilizing the resin injection / filling action. Therefore, the electronic component 4 and the lead frame 5 around the electronic component 4 are sealed in a resin-sealed molded body that is molded in accordance with the shapes of the cavities 9, so that the lower mold 2 is re-molded after the resin is cured. The lower mold is moved downward to open the upper and lower molds (1, 2), and at the same time as this, the resin-sealed molded body in both cavities 9 and the cured resin in the lead frame 5 and the resin flow path 11 are separated. The mold mechanism 12 may be used to release each mold.

[0003]

By the way, in the above-mentioned conventional mold structure, residual air and the like existing in the pot 8, the resin passage 11 and both cavities 9 are naturally discharged from the air vent to the outside. However, in the case of such natural discharge means of residual air, etc., void formation in the resin-sealed molded product is caused due to the fact that the discharge action is uncertain and incomplete. There was a problem that could not be effectively blocked.

Therefore, in order to solve the problem of void formation in the resin-sealed molded article, residual air and the like existing in the pot, the resin flow path and both cavities are forcibly discharged by the exhaust action of the vacuum source. Has been proposed (for example, JP-A-64-53555, JP-A-63-186435, JP-A-64-39033, etc.). These proposals, for example, when the upper and lower molds (1, 2) are clamped, as shown in FIGS. 9 and 10, through a seal member 13 provided around the mold surface of the upper mold 1. , The upper and lower mold (1 ・ 2) mold surfaces are isolated from the outside air,
In addition, the outside air cutoff range and a vacuum source provided outside are connected to each other through the air vent 14 and the vacuum path 15. However, such forced exhaust means
Although it is excellent in that the residual air and the like are not mixed in the molten resin material, it has not been put into practical use because it has the following technical problems.

For example, the seal member 13 is O
It is known that a ring is used, but in this case,
By pressing the O-rings when the upper and lower molds (1, 2) are clamped, the outside of the range set by the O-rings is cut off. When such means is adopted, the mold clamping of the upper and lower molds (1 and 2) and the external air blocking action by the seal member 13 are performed substantially at the same time. Even when the lead frame 5 is not fitted and set in a predetermined position and state for some reason, the mold clamping action and the external air blocking action are performed substantially at the same time. There is a serious problem that the die surface of (1) and 2) or the electronic component 4 or the lead frame 5 is damaged, and when the seal member 13 itself is damaged, the function of blocking the outside air by the seal member 13 is impaired. There is a problem.

Further, at the time of completely clamping the upper and lower molds (1, 2), it is necessary to prevent the resin burrs from being generated on the both mold surfaces. Since the mold surfaces of (1) and (2) are tightly and strongly bonded (pressure contact), the air remaining in the cavity 9 is passed through the air vent 14 provided at a specific place between the mold surfaces of the both molds (1 and 2). It will be discharged to the outside of the cavity 9. However, the air vent has the function of discharging the residual air in the cavity 9 to the outside and also prevents the molten resin material injected and filled in the cavity 9 from flowing out of the cavity 9 through the air vent. Since it is necessary to have such a function as well, its shape is usually formed from a small groove having a narrow width and a shallow groove as described above. Therefore, it is extremely difficult to discharge (vacuum) residual air in the cavity 9 to the outside only from the air vent when the upper and lower molds (1 and 2) are completely clamped, or both molds are closed. Even if the vacuum source exhausts during complete mold clamping, the efficiency of exhausting residual air, etc. existing between the mold surfaces of the two molds is poor, so set the outside air cutoff range to a vacuum state. Has a technical problem that is virtually impossible to expect.

The resin tablet 7 supplied into the pot 8 is heated and melted by the heating action of the heating means 3. The action of transferring the melted resin material into the cavity 9 is performed by moving the plunger 10 upward by a predetermined stroke 16. Therefore, in order to melt the resin tablet 7 in the pot 8, the heating action by the heating means 3 must be applied to the resin tablet 7 in the pot 8 as long as possible. On the contrary, since a thermosetting resin material is used for this type of resin material, the molten resin material must be transferred to the cavity 9 within a short period of time when it has fluidity. For this reason, if the heating action (heating time) on the resin tablet 7 is set longer than necessary, the overall resin molding cycle time becomes longer, the fluidity of the molten resin material is lowered, and The high-viscosity molten resin material to be injected and filled has a harmful effect such as damage to electronic parts. On the contrary, when the heating action on the resin tablet 7 is set to be shorter than necessary, the resin tablet 7 cannot be sufficiently heated, and therefore the resin tablet 7 cannot be sufficiently expanded by heating. Even if the inside of the pot 8 is evacuated in this state, the air, water, etc. contained in the resin tablet 7 cannot be discharged to the outside. There is an adverse effect such that voids are formed in the sealing molded body.

When the resin tablet is supplied into the pot and the resin tablet is heated and melted by the heating means and the plunger, before the resin tablet is supplied into the pot for the purpose of assisting the heating and melting action. ,
Preheating of the resin tablet is performed. However, since a coating layer of molten resin is formed on the surface of the pre-heated resin tablet, if this is supplied into the pot and the original heating action of the heating means of the mold is applied to this, the resin tablet internal A large amount of air and water contained in the molten resin cannot be flowed out to the outside, that is, inside the pot because of being hindered by the coating layer of the molten resin, therefore, the large amount of air and water is mixed in the molten resin material. There is a problem that it flows into the cavity as a void and is formed as a void in the surface portion and inside of the resin-sealed molded body.

The present invention not only surely discharges air and moisture remaining in the outside air cutoff range to the outside of the resin molding die, but is also contained inside the resin tablet supplied into the pot. The air and water that are inside the outside air cutoff range (in the pot)
Efficiently and surely and open it, and also discharge these outflowing air etc. to the outside efficiently and surely, and further to efficiently and reliably discharge the gases generated when the resin tablet is heated to the outside. By doing so, it is possible to reliably prevent the formation of voids in the resin encapsulation molded product by mixing these residual air, moisture, and generated gases into the molten resin material, and making sure to prevent the resin encapsulation molding. The purpose is to provide a method.

[0010]

A method of resin-molding an electronic component according to the present invention for solving the above-mentioned problems is a resin-molding die comprising a fixed die and a movable die opposed to the fixed die. Section, and at least the resin tablet supply pot provided in the mold section, the resin molding cavity, and the air remaining in the flow path section of the molten resin material that connects and connects the pot and the cavity. By molding a resin around the electronic component supplied into the cavity of the mold part, using a resin molding mold provided with a vacuum drawing means for forcibly sucking and discharging moisture to the outside of the mold part. A method of sealing the electronic component, the supplying process of the electronic component supplying the electronic component into the cavity, and the room temperature resin tab supplying the resin tablet at room temperature which is not preheated into the pot. In the pot, a step of supplying the liquid, a step of blocking at least the pot, the cavity, and the resin flow path provided in the mold portion from the outside air, and the room temperature resin tablet supplied in the pot in the pot. Heat expansion process of room temperature resin tablet to be expanded by heat,
A vacuum evacuation step of forcibly sucking and discharging air / moisture within the outside air interception range maintained by the outside air interception step to the outside of the mold section; and the fixed mold while maintaining the outside air interception step and the evacuation step. Complete mold clamping step of joining the movable mold and completely clamping, resin tablet pressurizing step of moving the plunger to press the resin tablet supplied into the pot, and heating in the pot part A resin injecting step of injecting and filling a melted molten resin material into the cavity through the resin flow path to form a resin around the electronic component in the cavity, and further pressing the resin tablet The moving speed of the plunger in the step is higher than a predetermined speed until the heating and expanding step of the room temperature resin tablet supplied into the pot is completed. The air and moisture in the outside air cutoff range are suctioned and discharged and the heating and expansion of the resin tablet causes the air and moisture released from the inside to be released and the heating of the resin tablet. All of the gases generated at this time are forcibly sucked and discharged to the outside of the mold.

Further, in the method for resin-sealing and molding an electronic component according to the present invention, before the above-mentioned complete mold clamping step, air, moisture and generated gas are provided between the facing surfaces of the fixed mold and the movable mold. The intermediate mold clamping step of the fixed mold and the movable mold, which leaves the suction and discharge gap, is provided.

Further, the method of resin-sealing and molding an electronic component according to the present invention comprises, in the above-mentioned intermediate mold clamping step, a vacuum drawing step of sucking and discharging air / water and generated gas within the outside air cutoff range. It is characterized by that.

Further, in the resin encapsulation molding method for an electronic component according to the present invention, at least the pot, the cavity, and the resin flow path provided in the mold part are shielded from the outside air in the outside air blocking step, The vacuum degree within the outside air cutoff range is set to 1 Torr or less, and in this state, the heat expansion step of the room temperature resin tablet for heating and expanding the room temperature resin tablet is performed. .

[0014]

According to the present invention, it is possible to supply a resin tablet at room temperature which has not been preheated to the inside of the pot, and to heat and expand it under a predetermined reduced pressure in the evacuation step. And in the resin tablet pressurizing step,
By setting the moving speed of the plunger to be a speed slower than a predetermined speed until the heating and expanding step of the room temperature resin tablet supplied into the pot is completed, Efficiently and forcibly exhausting all of the air and moisture released from the inside of the room temperature resin tablet by the heat expansion of the room temperature resin tablet and the gas generated during the heating of the room temperature resin tablet to the outside of the mold part. Can be sucked and discharged.

[0015]

1 to 8 schematically show the construction of a resin sealing molding apparatus for electronic parts. An upper mold (fixed mold) 101 mounted on the upper fixed platen and a lower mold (movable mold) 102 mounted on the lower movable platen are paired with this apparatus. Further, an upper die chase block 104 is detachably mounted on the die base 103 on the upper die 101 side by a fitting means such as a dovetail groove. Similarly, a die base on the lower die 102 side is mounted.
A lower chase block 106 is detachably attached to 105 by a fitting means such as a dovetail groove.

The lower chase block 106 includes heating means 107 such as a heater, a plurality of required resin tablet supply pots 108, and a required number of resins arranged at predetermined positions around each of the pots 108. Molding cavity 109
Etc. are arranged respectively. Further, below the lower die chase block 106, a lower ejector plate 111 having an ejector pin 110 and the lower die cavity 109 by moving the lower ejector plate 111 upward.
A vertical movement mechanism 112 for releasing the resin-sealed molded product molded in the mold, and a pre-heated normal temperature resin tablet 113 supplied to the pots 108 for individually pressurizing them respectively. Plunger holders 115 and the like having the plungers 114 are arranged respectively. The upper end of each ejector pin 110 is fitted into a pin hole 116 communicating with each lower mold cavity 109. The upper end of each plunger 113 is fitted into each pot 108 through the through holes 117 and 118 formed in the mold base 105 and the ejector plate 111, respectively. Further, the plunger holder 114 is detachably mounted on a rail member (not shown) arranged below the mold base 105.

The upper chase block 104 is equipped with a heating means 119 such as a heater. Also,
The upper mold chase block 104 includes the lower mold pots.
Cull portion 120 corresponding to the position and number of 108 and upper mold cavity 12 corresponding to the position and number of lower mold cavity 109.
1 and 2 are opposite each other. Then, each cull portion 120
The lower mold cavity 109 and the lower mold cavity 109 are provided so as to be communicatively connected to each other via a short resin passage 122 communicating with each other at the time of mold clamping shown in FIG. In addition, each of the upper mold cavities
121 is an air vent formed as required depth and width
123 are connected to each other. Further, the ejector pin 124 is provided above the upper chase block 104.
And an upper ejector plate 125 provided with a resin-sealed molded body formed in the upper mold cavity 121 by lowering the upper ejector plate 125 and the cull portion.
An up-and-down moving mechanism 126 and the like for releasing the resin molded body molded in 120 are respectively arranged. The lower end of each ejector pin 124 has a pin hole 127 communicating with each upper mold cavity 121 and a pin hole communicating with the cull portion 120.
Mated to 128 respectively.

A vacuuming mechanism (pressure reducing mechanism) 129 equipped with a vacuum source such as a vacuum pump is mounted on the upper surface of the upper mold base 103. Also, the upper die base 10
The PL surface (parting line surface) in 3 and the fitting portion of the upper ejector plate 125 are provided with intake holes 13
0 is opened respectively. Further, the vacuum evacuation mechanism 129
And the intake hole portion 130 are connected to each other through a through hole 131. In the illustrated example, the lower mold base 105
Although the vacuum evacuation mechanism, the intake hole portion, the through hole, etc. are not shown on the side, if necessary, the upper mold base
A structure similar to that of the 103 side may be arranged on the lower mold base 105 side.

In addition, the lower mold base 105 includes a lower mold 10
2 mold surface, that is, the PL of the lower mold chase block 106
At least each pot in the plane 108 ・ each lower mold cavity
An outer air blocking member 132 having a round tubular shape or a rectangular tubular shape that covers the outer periphery of the resin 109 and the resin passages 122 is fitted.
The outside air blocking member 132 is a mechanical drive mechanism such as a rack and pinion mechanism as shown in the figure, an electric drive mechanism such as an electric motor, or a fluid drive mechanism such as hydraulic or pneumatic pressure. It is provided so as to be slidable in the mold opening / closing direction via a driving mechanism 133. In addition, a suitable seal member 134 is disposed on the fitting surface between the lower mold base 105 and the outside air blocking member 132.

In addition, the upper die base 103 has an upper die 10
1 mold surface, that is, PL of the upper mold chase block 104
At least each cull portion 120 on each surface ・ Each resin channel 122 ・
Each upper mold cavity 121 is fitted with a round-tube / square-tubular outside air blocking member 135 that covers the outer periphery of each air vent 123, and the outside air blocking member 135 is a rack as shown in the figure. It is slidable in the mold opening / closing direction via an appropriate drive mechanism 136 consisting of a mechanical drive mechanism such as a pinion mechanism, an electric drive mechanism such as an electric motor, or a fluid drive mechanism such as hydraulic or pneumatic pressure. It is provided so that. Further, a suitable seal member 137 is disposed on the fitting surface between the upper mold base 103 and the outside air blocking member 135.

Also, the upper and lower molds (101 and 102) shown in FIG.
Of the upper and lower molds (101
・ 102) When the mold is completely clamped, both drive mechanisms (133 ・ 13
When both the outside air blocking members (132, 135) are moved forward in the mold clamping direction via 6), the tips of them are provided so as to be fitted. At this time, since a suitable seal member 138 is disposed on the tip end fitting surfaces of both the outside air blocking members (132, 135), the fitting parts can be sealed. In the illustrated example, the lower mold base 10
The upper end of the outside air blocking member 132 fitted in the
Move up to near the PL surface of 2 and also the upper mold base
The outside air shut-off member 135 fitted in 103 is attached to the lower mold base.
10 shows the case of fitting to the outer peripheral surface of the outside air blocking member 132 of 105. In the case of the example shown in the drawing, the both outside air blocking members (132, 135) are fitted to each other at their tip ends, but the tip surfaces of both members provided with an appropriate seal member are joined together. It does not matter if the configuration is adopted,
In short, it is sufficient that the seal member can block the flow of air and moisture between the two.

In addition, a suitable seal member 139 is interposed between the mold bases (103, 105) and the chase blocks (104, 106) and the like. Therefore, at the time of intermediate mold clamping and complete mold clamping of the upper and lower molds (101, 102) shown in FIGS. 3 and 4, the tip ends of the outside air blocking members (132, 135) should be fitted. Thus, the space between the mold surfaces of the upper and lower molds (101 and 102) is the member for blocking both outside air
(132/135) and the seal members (134/137/138/139) form a space 140 in which the outside air is blocked. Therefore, when the vacuum evacuation mechanism 129 is operated during the intermediate mold clamping shown in FIG.
108 ・ Cull part 120 ・ Resin flow channel 122 ・ Cavity (1
09/121) ・ For each air vent 123 and both upper and lower types (101 ・ 102)
The entire outside air blocking space 140 formed between the PL surfaces can be brought to a vacuum state (a reduced pressure state), and the air and water remaining in the outside air blocking space 140 and the pots
It is possible to forcibly suck and discharge the gas, which is generated when the resin tablet supplied inside is heated, to the outside.
Further, when the vacuum evacuation mechanism 129 is operated during the complete mold clamping shown in FIG. 4, the pots 108, the cull portions 120, the resin flow paths 122, the cavities (109, 121),
Air and moisture remaining in each air vent 123, the generated gas, etc., are passed through the air vents 123, and the upper and lower molds (101
・ 102) is forcibly sucked between the PL surfaces, and then forcibly sucked and discharged to the outside.
It is possible to maintain the vacuum state of the entire outside air blocking space 140. That is, the vacuum state in the outside air blocking space 140 is obtained by continuously performing the vacuum drawing step during the intermediate mold clamping of the upper and lower molds (101, 102) and the vacuum drawing step during the complete mold clamping. , Will be more certain.

Reference numeral 141 in FIG. 1 indicates a simultaneous material feeding and supplying device. The material simultaneous feeding and supplying device 14
Reference numeral 1 denotes a room temperature resin tablet 113 that has not been preheated and a lead frame 143 equipped with an electronic component 142, which are simultaneously conveyed and supplied to a predetermined position between the upper and lower molds (101 and 102). Attaching / detaching mechanism of the tablet 113 144
And the lead frame 143 attachment / detachment mechanism 145. The room temperature resin tablet 113 is placed in the lower mold pot 108 via the both attachment / detachment mechanisms (144, 145) and the lead frame 143. The lower mold cavity 109
Are provided so that they can be supplied into the fitting recesses 146 provided at predetermined positions. Also, the reference numerals in FIG.
Reference numeral 147 indicates a device for taking out the resin molded product. As will be described later, the resin-molded product take-out device 147 includes a sealed lead frame attaching / detaching mechanism 148 in which electronic components are resin-sealed. The resin encapsulation molded article, the lead frame, and the cured resin in the resin flow path) 149 are provided so as to be taken out of the upper and lower molds (101, 102).

A method of resin-molding the electronic component 142 mounted on the lead frame 143 using the resin-molding apparatus will be described below.

First, as shown in FIG. 1, the room temperature resin tablet 11 which is not preheated through the both attachment / detachment mechanisms (144, 145) in the material simultaneous feeding and supplying device 141.
3 and the lead frame 143 on which the electronic component 142 is mounted are engaged, and in this state, the material simultaneous feeding and supplying device 141
Is moved forward to a predetermined position between the upper and lower molds (101, 102).

Next, as shown in FIG. 2, the room temperature resin tablet 11 which is not preheated through the both attachment / detachment mechanisms (144, 145) in the material simultaneous conveying and supplying device 141.
3 and the lead frame 143, the room temperature resin tablet 113 is placed in the lower mold pot 108,
In addition, the lead frame 143 is attached to the lower mold cavity 10
Supply and set in the fitting recesses 146 of the 9 parts respectively. The room temperature resin tablets 113 supplied into the pots 108 are sequentially heated and expanded by the heating means (107, 119) and melted.

Next, the lower mold 10 is passed through the lower movable plate.
The upper and lower molds (101, 102) are clamped by moving 2 upwards. In this mold clamping step, for example, as shown in FIG. 3, intermediate mold clamping in a state where a required gap 150 is maintained between the upper and lower molds (101, 102) and as shown in FIGS. 4 and 5. , The lower mold 102 is further moved upward to move the upper and lower molds together.
Complete mold clamping with the mold surfaces of (101 ・ 102) joined. It should be noted that the intermediate mold clamping and the complete mold clamping are a continuous mold clamping operation in which both the operations are performed continuously for the purpose of shortening the overall molding cycle time, and the upper and lower mold clamping (101
102), for the purpose of more effectively performing the vacuuming action of the outside air blocking space 140 formed between the lower mold 10 and the lower mold 10
The stepwise mold clamping operation, such as performing the intermediate mold clamping with the upward movement of 2 stopped for a few seconds, is conceivable, either of which can be adopted.

Next, at the time of intermediate mold clamping and complete mold clamping shown in FIGS. 3 to 5 (or in parallel with these mold clamping operations), both drive mechanisms (133, 136) are used. Both the outside air blocking members (132, 135) are moved forward in the mold clamping direction, and their tips are fitted to seal the fitting portions of these tips. At this time, the upper and lower molds
Between the mold surfaces of (101/102), that is, between the PL surfaces of both molds, the both outside air blocking members (132/135) and the sealing members (134/137)
・ 138 ・ 139) will form the space 140 where the outside air is blocked.

Next, at the time of the mold clamping, the vacuuming mechanism 12
9 to operate each pot 108, each cull part 120, each resin flow path 122, each cavity (109, 121), each air vent
The entire inside of the outside air blocking space 140 formed between the PL surfaces of the 123 and the upper and lower molds (101, 102) is set to a vacuum state (for example,
Set the degree of vacuum in the outside air blocking space 140 to 1 Torr or less). As described above, when the vacuuming step is performed during the intermediate mold clamping, air and moisture remaining in the outside air blocking space 140, and the resin supplied into the pots 108 are retained. Gases generated when the tablet is heated can be forcibly sucked and discharged to the outside. Also,
When the evacuation step is performed during the complete mold clamping, each pot 108, each cull portion 120, each resin flow path 122, each cavity (109, 121), residual air in each air vent 123,
Moisture, generated gas, and the like can be forcibly sucked between the PL surfaces of the upper and lower molds (101, 102) through the air vents 123, and then similarly, can be forcibly sucked and discharged to the outside. Therefore, in both the intermediate mold clamping and the complete mold clamping, the vacuum state of the entire outside air blocking space 140 can be maintained and the outside air blocking space 140 can be maintained.
The inner vacuum state becomes more reliable by continuously performing the vacuum drawing process during the intermediate mold clamping and the complete mold clamping.

Next, during the complete mold clamping shown in FIGS. 4 and 5, as shown in FIGS.
By moving 114 upward, the molten resin material in the pot 108 is passed through the resin passages 122 and the cavities (109, 121)
A resin injection step of injecting into the inside is performed. At this time, resin is molded around the electronic component 142 on the lead frame 143 fitted and set in each cavity (109, 121) by the molten resin material injected and filled in each cavity (109, 121). Therefore, this allows the electronic component 142 to be resin-sealed. By the way, in the conventional resin injection process, as described above, since thermosetting resin material is used for this kind of molding, heating and melting of the resin tablet and cavity are performed in order not to lower the fluidity of the molten resin material. It is necessary to carry out the transfer and injecting action into the interior in a short time, and
For the purpose of shortening the overall resin molding cycle time, after the complete mold clamping step is performed, immediately after this, the resin tablet pressurizing step for moving the plunger 114 upward is performed. There is. In this case, the solid resin tablet 113 which is not sufficiently expanded by heating at the tip (upper end surface) of the plunger 114 is pressed against the cull portion 120. In other words, in the past,
By positively and strongly pressing the solid resin tablet against the cull portion, the resin tablet is sequentially heated and melted from the pressing surface of the cull portion. The resin tablet pressing step in the molding method according to the present invention shown in FIGS. 5 to 7 is different from the conventional resin tablet pressing step in the following points. That is, as shown in FIGS. 6 and 7, it is necessary to perform the resin injection step of injecting the molten resin material in the pot 108 into the cavities (109, 121) through the resin passages 122. Plunger
Of the predetermined stroke 151 of 114, the room temperature resin tablet 113 supplied into the pot 108 is heated and expanded in the pot 108 until the heat expansion step of the room temperature resin tablet is completed 152 (see FIG. 6). Is set so that the moving speed (upward moving speed) of the plunger 114 is slower than a predetermined moving speed of the plunger, and the heat expansion process of the room temperature resin tablet is completed and the room temperature resin tablet 113 is sufficiently After the heat-expanded state, the moving speed of the plunger 114 is set to a predetermined plunger moving speed. Therefore, until the heat expansion process of this room temperature resin tablet is completed, 152
Air and moisture remaining in the outside air blocking space 140,
The air and moisture released from the inside of the room temperature resin tablet 113 due to the thermal expansion and released, and all of the gases generated during the heating of the room temperature resin tablet 113 are external to the upper and lower molds (101/102). Can be forcibly sucked and discharged. Therefore, unlike the conventional case, since it does not heat and melt while pressing the solid resin tablet against the cull portion, air and water inside the resin tablet during the heating and melting are not melted in the molten resin material. It is possible to prevent the harmful effects of mixing.

Next, the molten resin material 153 heated and melted in the pot 108 is injected and filled into the respective cavities (109, 121) through the resin flow passages (cull portion 120, resin flow passage 122). Then, a resin injection step of molding a resin around the electronic component 142 is performed.

Next, as shown in FIG. 8, the resin molded product 149 is released between the upper and lower molds (101, 102) through the both vertical movement mechanisms (112, 126), and The 149 may be taken out through the resin molded product taking-out device 147.

The present invention is not limited to the above-mentioned embodiments, but can be arbitrarily and appropriately modified / selected as necessary within the scope of the gist of the present invention. Is.

For example, the moving speed of the plunger (predetermined moving speed) and the moving speed of the plunger (moving speed lower than the predetermined moving speed until the heating and expanding step of the normal temperature resin tablet are completed). The setting of) may be appropriately selected and determined according to the thermosetting resin material used.

[0035]

According to the present invention, the room temperature resin tablet is heated and expanded in the pot, and the moving speed of the plunger is kept lower than the predetermined moving speed of the plunger until the heating and expanding step is completed. The air and moisture remaining in the outside air blocking space, the air and moisture flowing out from the inside of the room temperature resin tablet due to the thermal expansion of the room temperature resin tablet, and the air and moisture released when the room temperature resin tablet is heated. Since all of the generated gases can be forcibly sucked and discharged to the outside of the mold part, the conventional adverse effect that the residual air, moisture, generated gases, etc. are mixed in the molten resin material is caused. In addition, it can be prevented efficiently and surely. Therefore, the resin of the electronic component that can prevent the formation of voids or defects due to the residual air, moisture, generated gas, etc. inside or on the surface of the molded resin-sealed molded product. There is an effect that a sealing molding method can be provided. Further, this brings about an excellent effect that a product of this kind having high quality and high reliability can be molded.

Further, according to the present invention, the moving speed of the plunger is lower than the predetermined moving speed of the plunger until the heating and expanding step of the normal temperature resin tablet in which the normal temperature resin tablet is heated and expanded in the pot is completed. And the room temperature resin tablet heat expansion step is completed and the room temperature resin tablet is in a sufficiently heat expanded state so that the moving speed of the plunger becomes a predetermined plunger moving speed. Since it is set, the entire resin molding cycle time can be shortened as compared with the case where the heat expansion step of the room temperature resin tablet is performed in the state where the movement of the plunger is completely stopped.

[Brief description of drawings]

FIG. 1 is a partially cutaway vertical sectional view schematically showing a main part of a mold in a resin sealing molding apparatus for electronic parts, showing a mold open state before resin sealing molding.

FIG. 2 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 1, showing a supply state of a lead frame on which a room temperature resin tablet and electronic parts are mounted.

FIG. 3 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 1, showing an intermediate mold clamping state.

FIG. 4 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 1, showing a completely clamped state.

FIG. 5 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 4, showing a heat expansion step of a room temperature resin tablet.

FIG. 6 is a partially cutaway enlarged vertical sectional view of a main part of a mold corresponding to FIG. 5, showing a heat expansion step of a room temperature resin tablet.

7 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 6, showing a resin injection step.

FIG. 8 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 1, showing a mold open state after resin sealing molding.

FIG. 9 is a partially cutaway vertical sectional view showing a main part of a mold in a conventional resin encapsulation molding apparatus for electronic parts, showing a mold open state before resin encapsulation molding.

10 is a partially cutaway vertical sectional view of a main part of a mold corresponding to FIG. 9, showing a complete mold clamping state at the time of resin sealing molding.

[Explanation of symbols]

101 Upper mold 102 Lower mold 103 Mold base 104 Upper mold chase block 105 Mold base 106 Lower mold chase block 107 Heating means 108 Pot 109 Lower mold cavity 110 Ejector pin 111 Lower ejector plate 112 Vertical movement mechanism 113 Room temperature resin tablet 114 Plunger 115 Plunger holder 116 Pin hole 117 Insertion hole 118 Insertion hole 119 Heating means 120 Cull part 121 Upper mold cavity 122 Resin passage 123 Air vent 124 Ejector pin 125 Upper ejector plate 126 Vertical movement mechanism 127 Pin hole 128 Pin hole 129 Vacuuming mechanism 130 Air intake Hole 131 Through hole 132 Outside air blocking member 133 Driving mechanism 134 Sealing member 135 Outside air blocking member 136 Driving mechanism 137 Sealing member 138 Sealing member 139 Sealing member 140 Outside air blocking space 141 Material simultaneous feeding and supplying device 142 Electronic component 143 Lead frame 144 Detachment mechanism 145 Detachment mechanism 146 Recess for fitting 147 153 molten resin material until butter product removal device 148 detachable mechanism between 149 resin molded article 150 gap 151 a predetermined stroke 152 cold resin tablet of thermal expansion step is completed

Claims (4)

[Claims] 1. A resin molding die portion comprising a fixed die and a movable die opposed to the fixed die, and at least a pot for supplying a resin tablet, a resin molding cavity and the pot provided on the die portion. And a mold for resin molding provided with vacuuming means for forcibly sucking and discharging air and moisture remaining in the flow path of the molten resin material, which is connected to the cavity, to the outside of the mold. A method for sealing the electronic component by molding a resin around the electronic component supplied into the cavity of the mold part using a method of supplying the electronic component into the cavity. A step of supplying a resin tablet at room temperature which is not preheated to the inside of the pot, and a step of supplying at least the pot, the cavity and the tree provided in the mold part; An outside air shutoff step of shutting off the oil flow passage from the outside air, a thermal expansion step of heating the ordinary temperature resin tablet supplied to the pot in the pot to heat and expand it, and an outside air maintained by the outside air shutoff step The stationary mold and the movable mold are joined while maintaining the vacuum evacuation process for forcibly sucking and discharging the air and moisture within the blocking range to the outside of the mold part, and the outside air blocking process and the vacuum evacuation process. A complete mold clamping step of completely clamping the mold, a resin tablet pressing step of pressing the resin tablet supplied into the pot by moving the plunger, and a molten resin material heated and melted in the pot portion. Inject and fill the cavity through the resin flow path,
A resin injection step of molding a resin around the electronic component in the cavity, and further, the moving speed of the plunger in the resin tablet pressing step is the heating of the room temperature resin tablet supplied into the pot. By setting so that the speed is slower than a predetermined speed until the expansion step is completed, suction and discharge of air and moisture within the outside air cutoff range, and the inside of the resin tablet due to the thermal expansion. A resin encapsulation molding method for an electronic component, which comprises forcibly sucking and discharging all the air and water that have flowed out and released and the gases generated during the heating of the resin tablet, to the outside of the mold section. 2. The fixed mold and the movable mold, wherein before the complete mold clamping step, a gap for sucking and discharging air, moisture and generated gas is left between the facing surfaces of the fixed mold and the movable mold. The resin encapsulation molding method for an electronic component according to claim 1, further comprising: 3. The resin for an electronic component according to claim 2, wherein the intermediate mold clamping step includes a vacuuming step of sucking and discharging air / water and generated gas in the outside air cutoff range. Encapsulation molding method. 4. In the outside air shutoff step, at least the pot, the cavity, and the resin flow path provided in the mold portion are shut off from the outside air, and the degree of vacuum in the outside air shutoff range is set to 1 Torr or less, The resin encapsulation molding method for an electronic component according to claim 1, wherein a heat expansion step of the room temperature resin tablet, in which the room temperature resin tablet supplied into the pot is heated and expanded, is performed in this state. .