JPS629216B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin-sealing mold for a semiconductor device in which an elastic body can be easily attached to and detached from a plunger head.

Generally, as shown in FIG. 1, a semiconductor device has its periphery sealed with a resin mold in order to protect the internal semiconductor element from mechanical and physical pressure from the outside. In addition, in Figure 1, 1
2 is a semiconductor device, and 2 is a lead.

FIG. 2 is a sectional view showing a conventional resin-sealing mold for a semiconductor device. In the figure, 3 is an upper surface plate attached to the upper platen of the molding press (not shown);
4 has a cavity 5, an upper mold attached to the upper surface plate 3, 6 a lower surface plate attached to the lower platen of the molding press (not shown), 7 a cavity 8, a runner 9 for guiding the resin, and a resin. It has a pot 10 for distributing resin to each runner 9, and a gate 11 for introducing resin into each cavity with good moldability, and a lower mold 12 attached to the lower surface plate 6 has one end penetrating the upper surface plate 3. The other end is a chamber attached to an injection cylinder of a molding press (not shown), 13 is a plunger movable in the vertical direction, and 14 is a detailed structure as shown in FIG. , a plunger head that is attached to one end of the plunger 13 and slides within the chamber 12.

In addition, in the plunger head 14 shown in Fig. 3, 15 is made of a material such as Teflon so as to withstand the molding temperature (generally around 180°C).
An elastic body 16 inserted into one end of the plunger 13
18a and 18b are head tops that are screwed to the threaded portion 17 of one end 13a of the plunger 13 to fix the elastic body 15;
It is a spanner hook installed on the side of the In addition, in order to attach and detach the elastic body 15, which is a consumable item, a spanner (not shown) is applied to the spout hooks 18a and 18b of the head top 16, and by turning the head top 16 and removing the head top 16 from the plunger 13, the elastic body 15 is removed. The body 15 can be replaced. The outer diameter of this elastic body 15 is equal to or slightly larger than the outer diameter D of one end 13a of the plunger 13. When the plunger 13 slides inside the chamber 12, the elastic body 15
It is provided to increase the degree of sealing between the plunger 13 and the chamber 12 so as not to damage the inner surface of the plunger 13 and the chamber 12. Furthermore, it goes without saying that the plunger 13 is provided with a spanner hook (not shown).

By configuring the resin-sealed mold as described above, the upper mold 4 and the lower mold 7 are combined and clamped for molding. That is, the plunger 13
After separating the plunger head 14 upward from the chamber 12, a predetermined amount of resin is poured from above the chamber 12, and then the plunger head 14 is separated from the chamber 12.
3 and the plunger head 14 are lowered,
The resin in chamber 12 is in chamber 12-pot 1.
It is injected into each cavity 5 and 8 via the 0-runner 9-gate 11, and resin sealing in a predetermined shape is completed.

However, in conventional resin molding molds for semiconductor devices, a gap is always provided between the chamber and the plunger head because the rigid bodies are fitted together. For this reason, when extruding resin during molding,
Although resin enters this gap, an elastic body is provided to prevent the resin from rising to the top of the plunger. As a result, the spanner hook on the head top is filled with resin. In this case, since the resin used for resin-sealing the semiconductor device is generally a thermosetting resin, the resin that enters the wrench hardens and is difficult to remove. Furthermore, since the elastic body is a consumable item, it is necessary to replace it frequently. For this reason, each time an attempt was made to replace the elastic body, the hardened resin within the wrench must be mechanically removed, resulting in a drawback of very low efficiency.

Therefore, an object of the present invention is to provide a resin-sealed mold for a semiconductor device that prevents resin from entering the spanner hook of the head top, ensures that the spanner is hooked on the spanner hook, and facilitates attachment and detachment of the elastic body. This is what we provide.

To achieve this object, the present invention includes a plunger head which is attached to one end of the plunger and slides within the chamber, and which is inserted into one end of the plunger and has an elastic body having an outer diameter equal to or slightly larger than the inner diameter of the plunger. , which is screwed to one end of the plunger to fix the elastic body and has a head top provided with a spanner hook consisting of a reverse tapered groove in the resin at the tip that becomes narrower as it gets deeper from this surface. This will be explained in detail using .

FIG. 4 is a sectional view showing one embodiment of a resin-sealing mold for a semiconductor device according to the present invention. In the figure, reference numeral 19 denotes a plunger head that is attached to one end of the plunger 13 and slides within the chamber 12, as its detailed configuration is shown in FIG.

In the plunger head 19 shown in FIG. 5, 20 is a head top that is screwed onto the threaded portion 17 of the plunger 13 to fix the elastic body 15. A spanner hook 1 is attached to the tip of the head top 20.
8a and 18b are provided. This spanner hook 18
a and 18b are tapered inversely from the surface 21 in contact with the resin.

Next, by configuring the resin-sealed mold as described above, the upper mold 4 and the lower mold 7 are combined and clamped to form the mold. That is, the plunger 13 and the plunger head 19 are connected to the chamber 1.
2, a predetermined amount of resin is poured into the chamber 12 from above, and then the plunger 13 and the plunger head 14 are lowered, and the resin in the chamber 12 is removed from the chamber 12 - pot 10 - runner 9 -. The resin is injected into each cavity 5 and 8 through the gate 11, and resin sealing in a predetermined shape is completed. In this case, the resin is always in contact with the surface 21 of the head top 20. Therefore, the interior of the spanner hooks 18a and 18b is also filled with resin, but after molding, the spanner hooks 18a and 18b are filled with resin.
The resin 22 that has entered the inside of b and hardened remains together with the cull as shown in FIG.
No resin remains inside a and 18b. Therefore, when replacing the elastic body 15, there is no need to mechanically remove the residual cured resin inside the spanner hooks 18a and 18b, and work efficiency is significantly improved. In addition, spanner hooks 18a and 1
For example, the reverse taper of 8b is good at around 15°, and the internal roughness is good at about 0.3 to 0.5S.

In the above embodiment, the wrench hook was formed in the recess, but as shown in FIG.
Of course, the same effect can be obtained by cutting off both ends of the 0 surface 21 to form a convex shape.

As explained in detail above, according to the resin-sealed mold for a semiconductor device according to the present invention, a spanner hook consisting of a reversely tapered groove that becomes narrower as it gets deeper is provided on the surface of the tip of the head top that comes into contact with the resin. Therefore, during resin sealing work, the resin that fills the inside of the spanner bar and hardens inside it remains together with the cull due to the reverse tapered groove structure of the spanner bar, and remains inside the spanner bar after molding. There is no need to mechanically remove the residual cured resin inside the wrench hook when replacing the elastic body, and the workability is greatly improved compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a semiconductor device, FIG. 2 is a sectional view showing a conventional resin molding mold for a semiconductor device, FIG. 3 is a detailed sectional view of the plunger head shown in FIG. 2, and FIG. 5 is a detailed sectional view of the plunger head shown in FIG. 4, and FIG. 6 explains the effect of FIG. 4. A cross section of the cal for,
FIG. 7 is a sectional view showing another example of the plunger head shown in FIG. 5. DESCRIPTION OF SYMBOLS 1... Semiconductor device, 2... Lead, 3... Upper surface plate, 4... Upper die, 5...... Cavity, 6... Lower surface plate, 7... Lower die, 8... Cavity, 9... Runner. , 10...pot, 11...gate, 12...
...Chamber, 13...Plunger, 14...Plunger head, 15...Elastic body, 16...Head top, 17...Threaded portion, 18a and 18b...
...Spanner hook, 19...Plunger head, 20
...head top, 21...head top surface,
22...Resin. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1 An upper surface plate attached to the upper platen of the molding press, a cavity is provided, an upper die attached to the upper surface plate, a lower surface plate attached to the lower platen of the molding press, the cavity, a runner to guide the resin, and a resin to each runner. A pot for distribution and a gate are provided to introduce the resin into each cavity with good moldability.
a lower mold attached to the lower surface plate; a chamber whose one end passes through the upper surface plate and is fixed to the upper mold; the other end of which is attached to an injection cylinder of a molding press; a plunger that moves within the chamber; In a resin-sealed mold for a semiconductor device, the plunger head is attached to one end of a plunger and slides within the chamber, and the plunger head is inserted into one end of the plunger and has an outer diameter that is equal to or slightly larger than the inner diameter of the plunger. an elastic body with a diameter;
A head top that is screwed to one end of the plunger, fixes the elastic body, and has a wrench hook on the surface in contact with the resin at the tip, which is a reversely tapered groove that becomes narrower as it gets deeper than this surface. Characteristics of resin encapsulation molds for semiconductor devices.