JP2893085B2 - Method and apparatus for resin sealing molding of electronic parts - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for resin-molding electronic components such as ICs, diodes, and capacitors, and an improvement in an apparatus therefor. The present invention relates to an improvement that efficiently and reliably discharges air remaining in a cavity.

[Conventional technology]

2. Description of the Related Art A transfer resin molding method and an apparatus therefor have conventionally been used to seal and mold an electronic component with a resin material.

This apparatus usually includes a fixed upper mold, a movable lower mold opposite to the fixed upper mold, and a resin sealing molding of electronic components opposed to the PL surfaces of both the fixed and movable molds. A cavity, a resin material supply pot disposed on the upper mold side, a resin material pressurizing plunger fitted in the pot, and pressurized transfer of the molten resin material in communication between the pot and the cavity. Passages and the like are provided.

In addition, resin sealing molding of electronic components by this,
A lead frame on which electronic components are mounted is set at a predetermined position on the lower mold PL surface, and in this state, the lower mold is moved upward to clamp both molds, and then the resin material is supplied into the pot. At the same time, this is pressurized by a plunger. At this time, the resin material is heated and melted by heaters provided in both molds and pressurized by a plunger, and is injected and filled into the upper and lower cavities from the pot through a transfer passage. Therefore, after the required curing time, the upper and lower molds are opened, and the cured resin molded bodies in both the cavities and the transfer passage are simultaneously released from the upper and lower ejector pins to form the molds in the two cavities. The electronic component can be sealed and molded in a resin molded body that is molded according to the shapes of the two cavities.

[Problems to be solved by the invention]

By the way, as shown in FIG.
When the molten resin material E is injected under pressure into cavities C and D having different depths opposed to the L surface, and the electronic component G on the lead frame F fitted and set in the cavities is molded with resin. Or, as shown in FIG.
Of the different cavity C · in D depths were oppositely arranged in PL surface, as well as fitted set lead frame F having a cross-section of different lengths inner leads (F ₁ · F _2), in the both said cavity When the molten resin material E is injected under pressure and the electronic component G on the lead frame F is molded with resin, there are the following technical problems in resin molding.

That is, the molten resin material injected into the cavities C and D tends to quickly flow and fill into the deep cavities C. For this reason, before the resin filling operation on the shallow cavity D side is completed, a part of the molten resin material flowing into the deep cavity C side, for example, the molten resin material at the leading end portion of the molten resin material flows into the air vent H. And hardens the remaining air after that.

Therefore, particularly, the air remaining on the shallow cavity D side is the surface of the shallow cavity D and the surface of the lead frame F, and the molten resin material E flowing into the shallow cavity D side.
₁ and between the molten resin material E ₂ flowing into the shallow cavity D side and flowing in the opposite direction because the air vent H is blocked by the resin that has flowed into and hardened after flowing into the deep cavity C side. To form a void I in the portion. For this reason, there is a serious problem that the moisture resistance and durability of the resin-encapsulated molded product are impaired, and the quality and reliability are reduced.

The present invention addresses the conventional problems as described above,
By efficiently and reliably discharging the residual air in the cavity to the outside of the cavity during resin sealing molding, and efficiently preventing the molten resin material flowing into the deep cavity from backflowing to the shallow cavity side, It is an object of the present invention to provide a resin sealing molding method and apparatus capable of molding a resin sealing molded product having high quality and high reliability.

[Means for solving the problem]

The resin sealing molding method for an electronic component according to the present invention includes:
A step of fitting and setting a lead frame on which electronic components are mounted in both cavities having different depths opposed to the PL surface, and clamping both the dies. A step of pressure-injecting a molten resin material from a gate provided at one end of each of the cavities to resin-mold an electronic component on the lead frame; Flowing the molten resin material into the resin reservoir through a passage, wherein the step of injecting the molten resin material into the resin reservoir includes a step of flowing the molten resin material into the two cavities. The portion is made to flow into the resin reservoir through a resin passage having an inclined cross section formed so as to be shallow at the communication port with the two cavity sides and deep at the communication port with the resin reservoir side. The Zantamari air in both said cavity and is characterized in that to perform the action to discharge through the resin passage both said cavity to the outside by the.

Further, the resin sealing molding method for an electronic component according to the present invention,
A step of fitting and setting a lead frame having inner leads having different cross-sectional lengths in both cavities having different depths opposed to the PL surface of both molds, a step of clamping the two molds, and a step of clamping the molds. A step of press-injecting a molten resin material into both cavities of the two dies from a gate provided at one end of the two cavities to resin-mold an electronic component on the lead frame; Flowing a part of the melted resin material into the resin reservoir through the resin passage. Is disposed on the gate side provided at one end of the cavity, and the short inner lead is disposed on the resin passage side communicating with the resin reservoir provided at the other end of the cavity. Further, in the step of flowing the molten resin material into the resin reservoir, a part of the molten resin material injected into the two cavities is shallow at the communication port portion with the two cavities and is formed with the resin reservoir side. By flowing into the resin reservoir through a resin passage having an inclined cross section formed so as to be deeper at the communication port portion, the residual air in both cavities is discharged through the resin passage to the outside of both cavities. It is characterized by performing.

In addition, the resin sealing molding device for electronic components according to the present invention,
A fixed mold, a movable mold opposed to the fixed mold, cavities having different depths opposed to the PL surfaces of both molds, a gate provided at one end of the cavity, and a gate position. A resin reservoir disposed near the other end of the cavity on the opposite side to the resin reservoir, a resin passage connecting the resin reservoir to the other end of the cavity, and a resin reservoir and the outside. A resin sealing and molding apparatus for an electronic component having an air vent communicated therewith, wherein a cross section of the resin passage is shallow at a communication port with the cavity and deep at a communication port with the resin reservoir. It is characterized by being formed in an inclined shape.

[Action]

According to the present invention, even when using a resin molding apparatus in which both cavities having different depths are opposed to the PL surface of both molds, the molten resin material is pressed from the gate provided at one end of the cavity. By injecting and allowing a part of the injected molten resin material to flow into the resin reservoir through the resin passage provided at the other end of the cavity, the residual air in both cavities can be discharged and the shallow cavity side can be discharged. And the backflow of the molten resin material can be efficiently and reliably prevented.

Further, an inner lead having a long cross-sectional length is arranged on the gate side provided at one end of the cavity, and the short inner lead is arranged on a resin passage side communicating with a resin reservoir provided at the other end of the cavity. In particular, a void forming portion (that is, residual air) which is likely to be generated on the shallow cavity side
Is efficiently transferred to the resin passage side provided at the other end of the cavity by utilizing the flow action of the molten resin material injected under pressure from the gate, and is transferred to the resin passage, the resin reservoir and the air vent. Can be efficiently and reliably discharged to the outside through the

Furthermore, by forming the shape of the resin passage in a cross-section inclined so as to be shallow at the communication port portion with the cavity side and deep at the communication port portion with the resin reservoir portion side, the resin molded body after the resin molding is formed. Since the cutting and separation from the resin passage is facilitated, the cutting and separating step between the resin molded body and the cured resin which is unnecessary as a product can be efficiently performed.

〔Example〕

Hereinafter, the present invention will be described with reference to the embodiment diagrams shown in FIGS. 1 to 4.

FIGS. 1 and 2 show a mold opening state and a mold clamping state of a main part of a mold in the resin molding apparatus, respectively. Movable lower mold 2
It is composed of

Cavities having different depths, ie, cavities 3 having a large cross-sectional depth on the upper mold 1 side, and a cross-sectional depth on the lower mold 2 side are provided on the PL surfaces of the upper and lower molds (1, 2). Are formed respectively.

At one end of the PL surface of the lower die 2 on the side of the lower die cavity 4, a gate 5 for injecting a molten resin material into the cavity under pressure is formed.

In addition, a resin reservoir 6 having a required shape and cross-sectional depth is provided near the other end of the lower mold cavity 4 opposite to the gate position.

The resin reservoir 6 and the other end of the lower mold cavity 4 communicate with each other through a required resin passage 7.
The resin reservoir 6 communicates with the outside through a required air vent 8.

A lead frame 10 on which the electronic component 9 is mounted is provided at a predetermined position of the lower mold cavity 4 on the PL surface of the lower mold 2.
The fitting set groove 11 is formed.

Therefore, as shown in FIG. 2, the lead frame 10 is fitted and set in the setting groove portion 11, and in this state, both types (1.
2) When the mold is clamped, the gate 5 and both cavities (3.4), resin passage 7, resin reservoir 6, and air vent 8
Are connected to each other.

The cross-sectional depth of the resin passage 7 and the air vent 8 described above, the degree of the molten resin material (13 _1, 13 _2), or the Zantamari air of both the cavity (3, 4) inside can be respectively transported Is provided as a depth.

That is, cross-sectional depth 1 ₁ of the resin passage 7, Intermediate depth rather formed by surely intended resin inlet effect on the above-mentioned resin reservoir 6, The cross-sectional depth 1 ₂ of the air vent 8, It is formed to be slightly shallow mainly for the purpose of discharging only the residual air transferred into the resin reservoir 6 (for example, both cavities 3.
To increase the inflow efficiency of the molten resin material 13 _1, 13 ₂ that flows from the 4 side, the molten resin material which has flowed into the resin reservoir 6 is for the purpose of suppressing the flowing into the air vent 8 side, the cavity 4 side about 0.1m sectional depth 1 ₁ in the communicating mouth of the
to m, or may be adopted a configuration in which setting the cross-sectional depth 1 ₂ air vent 8 to about 0.05 mm).

The shape of the resin passage 7 described above is formed so as to be shallow at the communication port with the lower mold cavity 4 side and deeper at the communication port with the resin reservoir 6 side. I have. Therefore, when such a configuration is adopted, it is easy to cut and separate the resin molded body and the resin passage 7 after the resin molding, so that the cured resin (the resin passage 7. There is an advantage that the step of cutting and separating the resin reservoir 6 and the unnecessary cured resin in the air vent 8 can be efficiently performed.

Reference numeral 12 in the drawing denotes an ejector pin for releasing the resin molded body molded in each of the cavities (3, 4).

 Next, the method of the present invention will be described.

As described above, the lead frame 10 is
When the upper and lower molds (1 and 2) are closed (see FIG. 2) and the molten resin material 13 is injected under pressure from the gate 5 provided at one end of the lower mold cavity 4, Since this molten resin material has a required viscosity and the upper mold cavity 3 side has a wider space than the lower mold cavity 4 side, it is injected into the deep upper mold cavity 3 side. the molten resin material 13 ₁ would then flow faster than the molten resin material 13 ₂ injected into the lower cavity 4 side is filled into the upper cavity.

However, this time, a part of the upper mold cavity 3 molten resin material 13 that has flowed into the side _1, for example, when the inflow tip portion reaches the other end of the cavity, the molten resin material of the moiety is upper and lower mold sections The resin is sequentially flown into the resin reservoir 6 through the resin passage 7 provided on the PL surface of (1.2).

Further, the molten resin material 13 ₂ which has flown into the shallow lower cavity 4 side is slower than the resin filling action of flowing molten resin material 13 ₁ in the deep upper mold cavity 3 side, partially through the resin passage 7 While flowing into the resin reservoir 6,
As shown in FIG. 2, while reaching the other end side of the shallow lower mold cavity 4, the inflow tip portion flows into the resin reservoir 6 through the resin passage 7.

Namely, deeper molten flowed into the upper mold cavity 3 side resin material 13 ₁ has reached the other end of the cavity, the resin through the resin passage 7 in which a part of the resin material is provided on the other end portion since flowing into the reservoir 6, the molten resin material 13 ₁ is shallow lower cavity 4 reaches the other end of the cavity
Through the gate 5 can be reliably prevented.

Further, the inflow tip portion of the molten resin material 13 ₂ which has flown into the shallow lower cavity 4 side, as in the case of inflow tip portion of the molten resin material 13 ₁ flowing into the upper die cavity 3 side, the molten resin material 13 ₁ is to be flowed into the resin reservoir 6 through the resin passage 7 with the resin inlet effects is introduced into the resin reservoir portion 6 side.

For this reason, the residual air in the upper and lower cavities (3, 4) has the above-mentioned inflow / filling action of the molten resin material and a resin inflow action in which a part of the air flows into the resin reservoir 6 through the resin passage 7. , And are efficiently and reliably discharged to the outside of the cavity.

Refers changing the flow velocity, filling time of the resin in the deep upper mold molten resin material flowing into the cavity 3 side 13 ₁ of the upper mold cavity, a shallow lower cavity 4 side has been molten resin material 13 ₂ flows into It becomes faster than the flow rate and filling time of the resin in the lower mold cavity.

However, deep while the molten flowed into the upper mold cavity 3 side resin material 13 _first part of which flows through the resin passage 7 into the resin reservoir 6, the molten resin flowing into the shallow lower cavity 4 side the material 13 flows and filling action and a portion of the ₂ and performs an action of flowing through the resin passage 7 into the resin reservoir 6.

Therefore, the residual air in the upper and lower cavities (3, 4) is supplied to the resin passage 7 based on the resin filling operation into the upper and lower cavities (3, 4) and the resin inflow operation into the resin reservoir 6.
And the resin reservoir 6 and the air vent 8 communicating with the resin reservoir, and the residual air discharged sequentially to the outside is discharged efficiently and reliably.

The lead frame The present invention is particularly, as shown in FIG. 3, with different two cavities (3, 4) in the depths, cross-sectional length of different inner lead (14 _1, 14 ₂₎ In the case where the electronic component 15 on the lead frame 14 is molded with resin while the molten resin material 13 is injected under pressure into both the cavities while the fitting and setting of 14 are performed, more remarkable functions and effects can be obtained. It is something that can be done.

That is, a long inner lead 14 ₁ of section length 1 ₃ of the lower mold cavity 4 is disposed on the gate 5 side provided at one end portion, and, the cross-sectional length 1 ₄ short inner lead 14 ₂ of the cavity 4 It is arranged on the side of the resin passage 7 communicating with the resin reservoir 6 provided at the other end, and the molten resin material 13 is injected under pressure from the gate 5 and the injected molten resin material (13 ₁
By flowing a part of 13 ₂ ) into the resin reservoir 6 through the resin passage 7, the residual air in both cavities is respectively discharged to the outside of the cavity through the resin passage 7, the resin reservoir 6, and the air vent 8. The remaining air to be discharged may be discharged.

Such an operation of injecting resin material into both cavities (3.4) under pressure, a resin filling operation in both cavities (3.4), and a residual air discharging operation in both cavities (3.4) ( The operation of flowing the resin into the resin reservoir 6) and the like are performed in substantially the same manner as the above-described method. However, the above-described method is more efficient particularly in terms of the operation of discharging the residual air.

That is, according to the method of the present invention, as described above, the molten resin material 13 that has flowed quickly into the deep upper mold cavity 3 side.
₁ can be reliably prevented from flowing from the other end of the cavity to the shallow lower mold cavity 4 side and flowing in the opposite direction, so that the molten resin material 13 flowing into the shallow lower mold cavity 4 side can be prevented. it is possible to efficiently and reliably transfer the Zantamari air of the lower mold cavity 4 to the other end side of the cavity on the basis of the flow and the filling action of _2, one of the molten resin material 13 ₂ described above The remaining air can be reliably discharged to the outside of both cavities (3.4) along with the action of flowing the portion through the resin passage 7 to the resin reservoir 6 side.

According to the method and configuration of the above-described embodiment, the residual air in the upper and lower cavities (3, 4) during resin sealing molding can be efficiently and reliably discharged to the outside of the cavities.

Further, it is possible to prevent the molten resin material 13 ₁ flowing into the upper cavity 3 side from flowing back to the shallow lower cavity 4 side efficiently.

Therefore, it is possible to reliably prevent the voids based on the residual air in the cavity from being formed in the resin molded body, so that it is possible to form a resin molded article having high quality and high reliability. There is an effect that a molding method and an apparatus therefor can be provided.

It should be noted that the present invention is not limited to the above-described embodiments, and can be arbitrarily and appropriately changed / selected as needed and adopted without departing from the spirit of the present invention. .

For example, a configuration in which the gate 5, the resin passage 7, and the air vent 8 provided on the lower mold 2 are disposed on the upper mold 1 may be adopted.

Further, at the time of resin molding, the resin material is filled and hardened in the resin passage 7, the resin reservoir 6, and the air vent 8, respectively, so that an ejector pin for releasing the unnecessary hardened resin is made of, for example, resin. It is also possible to adopt a configuration in which both the upper and lower mold positions corresponding to the position of the reservoir 6 are arranged.

〔The invention's effect〕

According to the present invention, as described above, the residual resin air in the cavity at the time of resin sealing molding can be efficiently and reliably discharged to the outside of the cavity, and the molten resin material flowing into the deep cavity side And a resin sealing molding method capable of efficiently and reliably preventing backflow into the shallow cavity side, thereby forming a resin sealing molding of an electronic component having high quality and high reliability. This provides an excellent practical effect that the device can be provided.

Furthermore, by forming the shape of the resin passage in a cross-section inclined so as to be shallow at the communication port portion with the cavity side and deep at the communication port portion with the resin reservoir portion side, the resin molded body after the resin molding is formed. Since it is easy to cut and separate from the resin passage, excellent practical effects such as efficient cutting and separating of the resin molded body and the cured resin which is unnecessary as a product can be achieved.

[Brief description of the drawings]

FIG. 1 is a partially cut-away longitudinal front view showing a main part of a mold and a main part of a lead frame in a resin molding apparatus according to the present invention, and shows a mold open state of the mold. FIG. 2 is a partially cutaway vertical sectional front view corresponding to FIG. 1, showing a state in which the mold lead frame is set and clamped. FIG. 3 is a partially cut-away vertical front view of a main part of the mold corresponding to FIG. 2, and shows a state in which another lead frame is set on the mold and the mold is clamped. FIG. 4 is a partially cutaway vertical sectional front view showing a main part of a lower mold in the mold corresponding to FIG. FIG. 5 is a partially cutaway vertical sectional front view showing a main part of a mold and a main part of a lead frame in a conventional resin molding apparatus, and shows a state where the lead frame is set in the mold and the mold is clamped. Is shown. FIG. 6 is a partially cutaway vertical sectional front view corresponding to FIG. 5, and shows a state in which another lead frame of the mold is set and clamped. 1 Upper die 2 Lower die 3.4 Cavity 5 Gate 6 Resin reservoir 7 Resin passage 8 Air vent 9 Electronic component 10 Lead frame 11 Set Groove portion 12 Ejector pin 13 (13 ₁ 13 ₂ ) Molten resin material 14 Lead frame 14 ₁ 14 ₂ Inner lead 15 Electronic component 1 ₁ 1 ₂ … Depth of section 1 ₃・ 1 ₄ …… Cross section length

Claims (3)

(57) [Claims] 1. A step of fitting and setting lead frames each having an electronic component mounted in both cavities having different depths opposed to PL surfaces of both molds, and clamping the molds. A step of press-injecting a molten resin material into both cavities of the mold from a gate provided at one end of both cavities to resin-mold an electronic component on the lead frame; Allowing the part of the molten resin material to flow into the resin reservoir through the resin passage, wherein the step of flowing the molten resin material into the resin reservoir comprises: A part of the molten resin material injected into the resin passage is passed through a resin passage having an inclined cross section formed so as to be shallow at the communication port with the both cavities and deep at the communication port with the resin reservoir. By flowing into the resin reservoir, the resin encapsulation molding method of an electronic component, characterized in that the Zantamari air in both said cavity performs the function of discharging through the resin passage both said cavity to the outside. 2. A step of fitting and setting a lead frame provided with inner leads having different cross-sectional lengths in both cavities having different depths facing the PL surfaces of both dies, and a step of clamping the two dies. And a step of resin-molding an electronic component on the lead frame by press-injecting a molten resin material from both gates provided at one end of the two cavities into the two cavities of the two dies, and Flowing a part of the molten resin material injected into both the cavities into the resin reservoir through the resin passage, the resin sealing molding method of the electronic component, wherein the fitting setting step of the lead frame, An inner lead having a long cross-sectional length is disposed on a gate side provided at one end of the cavity, and a resin passage side communicating the short inner lead to a resin reservoir provided at the other end of the cavity. Further, the step of injecting the molten resin material into the resin reservoir portion is configured such that a part of the molten resin material injected into the two cavities is shallow at a communication port with the two cavities and By flowing into the resin reservoir through a resin passage having an inclined cross section formed to be deeper at the communication port with the resin reservoir, the residual air in both cavities is passed through the resin passage. A method of resin-sealing and molding an electronic component, wherein the method includes discharging the resin to the outside of the cavity. 3. A fixed mold, a movable mold opposed to the fixed mold, cavities having different depths opposed to the PL surfaces of both molds, and a gate provided at one end of the cavity. A resin reservoir disposed near the other end of the cavity opposite to the gate position; a resin passage communicating the resin reservoir with the other end of the cavity; A resin sealing molding device for an electronic component, comprising: an air vent communicating a portion with the outside, wherein the resin passage is formed to be shallow at a communication port portion with the cavity side and a communication port with the resin reservoir portion side. A resin sealing and molding apparatus for an electronic component, wherein the apparatus is formed so as to have a cross section that is deeper in a portion.