JPS5817624A - Injection molding machine for semiconductor device - Google Patents

Abstract

PURPOSE:To enable to stably mix main agent and catalyst at the stable ratio and to stably operate an injection molding machine without hardening a catalytic pipe by providing a drive unit moving in a main agent pipe to supply or stop the catalyst to the main agent. CONSTITUTION:Main agent is fed under pressure from a main agent pipe 8. Catalyst is led from a catalyst tank 7 through a catalyst pipe 12, a control valve 6 and a valve 5 to a filling pipe 22, and is filled to the main agent in a main agent pipe 8 through a hole 21. This filling is performed at the center of the pipe 8. The main agent mixed with the catalyst is fed to a mixer 3, is then mixed and is fed under pressure to a mold. when the mold is completely filled and the flow of the main agent is stopped, or when a long time working is not carried out, a movable plate 18 is moved by a drive unit 13, and the position of the injection port of the pipe 22 is disposed outside the pipe 8. In this manner, the catalyst can be completely isolated from the main agent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an injection molding apparatus for semiconductor devices.

In recent years, transfer molding of electronic components such as semiconductor devices using thermosetting molding materials has been commonly used to protect internal semiconductor elements from the outside air. Injection molding, a so-called liquid transfer method, is being used to improve properties, molding time, resin efficiency, etc. The present invention relates to a molding apparatus used for liquid transfer molding.

In the injection molding method, a method was first attempted in which the liquid synthetic resin main ingredient and the catalyst were placed in separate containers, each was passed through separate pipes, and the two liquids were mixed at a precise mixing ratio just before the mold. ing. The advantage of this molding method is that the main ingredient and catalyst are separated right up to the injection port, so the chemical reaction does not proceed (
Stable characteristics can be obtained, and the low resin viscosity prevents defects (such as wire breakage) caused by molding of semiconductor devices with complex structures.
This is particularly important.Furthermore, the resin price is low and automation is easy.

However, there is currently no suitable method for supplying a catalyst to the base material for injection molding of this liquid resin, and as a result, practical application to mass production has been delayed.

First, a liquid resin injection molding method will be explained with reference to FIG. 1, which is a schematic diagram.

In Figure 1, 1 is a mold, 2 is a synthetic resin main agent tank, 3 is a mixer, 4 is its injection port, and 5 is the catalyst supply ON.
, pulp to be turned off, 6 a regulating valve for adjusting the flow rate of the catalyst, 1 a catalyst tank, and 8 a main material pipe connected to a mixer 3 for mixing the catalyst and the main material. 9 is a catalyst pipe, 10
is the mounting part.

In this state, main agent tank 2. Apply pressure to the catalyst tank 7,
A preset amount of catalyst is mixed with the main material using a regulating valve 6, the mixture is sufficiently mixed using a mixer 3, and the mixture is injected into a mold 1 and molded. The injection port 4 is brought into contact with the metal 1 and the mixed resin W* is sent into the room.

When the mold 1 is filled with resin, the pulp (not shown) in the mixer 3 is closed and the supply of the fat 11 is stopped. At the same time, the pulp 5 is closed to stop the supply of catalyst. By repeating this process, the desired molding is completed. The problem here is how to handle the catalyst when the supply of resin is stopped.

The amount of catalyst supplied to the base material is very small (1:0.01 in the case of semiconductors). When the supply of resin is stopped, that is, when the flow of the main agent is stopped, the catalyst supply line is closed by the pulp 5, but the space between the pulp 5 and the main agent pipe 80, that is, the catalyst pipe 9 is filled with catalyst. ing. This catalyst flows out into the main material due to fluctuations in internal pressure due to supply and stop of the main material. This means that the mixing ratio of the catalyst to the main ingredient is different, which greatly affects the performance of the semiconductor device. In addition, when the supply of the base agent is stopped for a long time, for example when the work is stopped at night, when the work is stopped in the above condition, the base agent and the catalyst may react and harden at the contact point, or the base agent pipe 8 may Due to the ratio of the diameters of the catalyst pipes 9, a pressure difference occurs between the main agent pipe 8 and the catalyst pipe 90, causing the main agent to flow back into the catalyst pipe s and harden. .

This invention has been made in view of the above points.

This invention will be explained below.

Figure 2 shows a disaster example of this invention, and Figure 3 shows its lI.
The details of the section are shown. In FIG. 2, the catalyst tank 1 is attached to a mounting plate 11. Pulp 5. The regulating valve 6 is attached to a movable plate 18. The movable plate 18 also includes the bearing 11 housed in the holder 16, the shaft 15 attached to the mounting portion 101C, and the drive device 1.
3 and the mounting of the movable plate 18 through AI4'4 and the shaft 15.
is configured to move in the axial direction. 22 has a hole 21 through which the catalyst is injected with an injection pipe;
is halfway through injection bites 22. 19 is a holding screw; 20 is a packing; the injection bite 22 passes through the main agent pipe 811; and the holding screw 19. This is prevented with Patsukin 20.

The injection pipe 22 is connected to the pulp 5, and the pulp S, aIl regulating valve 6° catalyst tank T is connected to the catalyst pipe 12.
are connected.

Next, to explain the operation, the main agent is pumped from the main agent pipe 8,
The catalyst is supplied from the catalyst tank 1 through the catalyst vibrator 12, the regulating valve 6, and the pulp 5 to the injection pipe 22, and is injected into the main material in the main material pipe 8, which is heated through the hole 21. The injection is carried out at the center of the main material pipe 8. The main material containing the catalyst enters the mixer 3, where it is mixed and then pumped into the metal interior.

When injection into the mold is completed and the flow of the base material has stopped, or when no work is to be done for a long time, the movable plate 111 is moved by the driving device [13] to the state shown in FIG. Position the outlet outside the main agent pipe 8. This completely separates the catalyst from the main component.

Further, a part of the injection pipe 22 remains inside the main agent pipe 8 and is in contact with a portion of the packing 20, so that the main agent does not flow out of the main agent pipe 8.

Here, the timing for inserting and removing the injection pipe 22 is determined as follows. When the base material is injected into the mold, the base material is flowing inside the base material pipe 8. It will stop when the injection is finished. As a result, the change in pressure in the main agent pipe 8 in the former and latter cases 'Ik:a' can be determined and the injection pipe 22' can be moved in and out according to the signal. That is, the pressure is low when the base agent is flowing, and the pressure is high when it stops. All you have to do is catch this signal and operate it. In addition, if the work is to be stopped for a long time, the hole 21 of the injection pipe 22 may be exposed outside the gasket 20 as shown in Figure 3 0) 'A40). In this way, when the base agent is stopped, the catalyst does not come into contact with the base agent, so there is no change in the amount of catalyst to the base agent due to changes in pressure, and there is no backflow of the base agent into the catalyst pipe 12. In addition, the resin does not harden when the work is stopped for a long time (the pot life of the main ingredient alone is 10 days or more at room temperature).

In the above embodiment, a drive device consisting of a cylinder and a piston was used, but any drive device may be used as long as it makes reciprocating motion. In addition, the catalyst injection pipe 22 and the main agent pipe 8
Although I used U-Putsukin for this purpose, the same effect can be obtained with O-ring, etc.

As explained in detail above, according to this invention, the ratio of the main ingredient and the catalyst can be mixed stably, and a semiconductor device of good quality can be obtained. Also, the catalyst pipe can be operated stably without hardening, and automation is possible. It has the advantage of being easy.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an apparatus for explaining the outline of the injection molding method, FIG. 2 is a configuration diagram showing a part of the injection molding apparatus in cross section showing an embodiment of the present invention, and FIG. FIG. 2 is a partial cross-sectional view of the main part of FIG. 2; In the figure, 1 is a mold, 2 is a main agent tank, 3 is a mixer, 1 is a catalyst tank, 8 is a main agent pipe, 12 is a catalyst pipe, 13 is a drive device, 18 is a movable plate, 19 is a cap screw, and 20 is a packing. , 21 is a hole, and 22 is an injection pipe. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Shin Kuzuno - (1 other person)

Claims (1)

[Claims] A mold consisting of a base agent tank, a mixer, a base agent pipe for transferring the resin from the base agent tank to the mixer, a catalyst pipe for transferring the catalyst from the catalyst tank into the base agent pipe, and a mold for molding the resin to predetermined dimensions. In sealing, an injection pipe connected to the catalyst pipe and having a catalyst transfer hole is provided to penetrate through a part of the base material pipe having a holding screw and a packing, and the injection pipe is connected to the
An injection molding apparatus for a semiconductor device, comprising: a drive device that moves the main material in the pipe so as to supply or stop the main material.