JP2000353759A - Manufacture of hollow plastic package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the trouble, where an inner lead sags down under its own weight or a down pressure of resin that flows in to prevent its tip from being brought into close contact with the bearing surface of an upper die, so that resin is filled into a gap between the bearing surface and the inner lead when resin is filled into a molding die, and as a result, a chip is sealed up with the resin, without making the inner lead exposed in a hollow. SOLUTION: In a hollow plastic package manufacturing method, where the package is molded making a chip mount hollow, a lead is made to bear against the lead-bearing surface of one molding die provided with a protrudent part for forming a hollow by the use of a support pin that protrudes from the other molding die which does not forms a hollow, and then resin is poured for molding. Or a lead is made to bear against the lead-bearing surface of one molding die, provided with a protrudent part for forming a hollow by the use of a support block that protrudes from the other molding die which forms no hollow, and then resin is poured for molding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a hollow portion inside, for example, a package of a CCD device,
The present invention relates to a method for manufacturing a hollow plastic package in which a lead electrode is exposed in a hollow portion and is electrically connected to a chip.

[0002]

2. Description of the Related Art In recent years, a package of a CCD device, for example, an image pickup device of a type which has a space inside and is sealed with a transparent cover after a chip is mounted thereon, is an epoxy as shown in FIG. The adoption of plastic packages using resin and the like is increasing. The hollow package is different from a solid package such as a normal semiconductor package in that the chip 1 is mounted after molding and the electrode on the chip is electrically connected to the hollow lead, so that the lead 1 is exposed in the hollow part. There is a need.

FIG. 2 shows the concept of a conventional resin molding method for a hollow package. According to the conventional method of manufacturing a hollow package shown in FIG. 2, the upper die is manufactured so that the grip surface S1 of the upper outer lead and the upper die contact surface S2 are coplanar. However, since the distance between the inner leads joined to the chip is designed to be relatively narrower than the distance between the outer leads in most cases, the inner lead is usually located at the center of the hollow plastic package in plan view as shown in FIG. The lead is short as L1 and longer as L2 toward the end.

In such a case, the lead must be in close contact with the upper-type lead contact surface S2 for forming the exposed surface of the hollow lead, but in reality, the lead's own weight as shown by L3 in FIG. Or, the inner lead hangs down due to the downward pressure of the flowing resin, and the tip does not adhere to the contact surface of the upper mold.When the resin is filled in this state, the resin enters between the contact surface and the lead, and as a result, As a result, there has been a problem that the lead is molded in a state where the lead is not exposed to the hollow portion. Further, in addition to the sagging of the inner lead due to its own weight, the L4 lead gripping surface S in FIG.
When the lead L4 is gripped by the upper and lower dies as shown in 3, there is a case where the alignment of the upper and lower dies is misaligned, and the misalignment causes a stress to be transmitted to the inner lead to cause distortion, thereby maintaining horizontality. However, the tip does not come into close contact with the contact surface of the upper mold, and when the resin is filled in this state, the resin enters between the contact surface and the lead as in the above case, and as a result, it enters the hollow part. There has been a problem that the leads are molded without being exposed. A hollow package molded with no leads exposed in the hollow part is naturally useless because the leads that should be connected to the chip electrodes are not exposed in the hollow part even if the chip is mounted inside. They had to be discarded as defective.

[0005]

As described above, according to the resin molding method of a hollow package according to the prior art, as described above, the inner lead hangs down due to the weight of the lead or the downward pressure of the resin flowing into the inner package. The part does not adhere to the contact surface of the upper mold, and when resin is filled in that state, the resin enters between the contact surface and the lead, and as a result, the mold is molded without the lead being exposed in the hollow part. In addition to the fact that it occurred and the sagging of the inner lead due to its own weight, when the lead was gripped by the upper and lower molds, the upper and lower molds could be misaligned. Stress is transmitted and distortion occurs, so that the level cannot be maintained and the tip does not come into close contact with the contact surface of the upper mold. Filling the resin between the contact surface and the lead in the same manner as described above, resulting in a problem that the lead is molded in a state where the lead is not exposed in the hollow portion, and these Due to the defect of the above, the hollow package that was molded without the lead exposed in the hollow part, because the lead that should be connected to the chip electrode even if the chip is mounted inside is not exposed in the hollow part, Naturally, it had to be discarded as a defective product instead of being used.

[0006]

According to the present invention, as a means for achieving the above-mentioned object, a method for manufacturing a hollow plastic package in which a chip mounting portion is molded in a hollow form is disclosed. A method of manufacturing a hollow plastic package, comprising: performing resin molding in a state in which a lead is brought into contact with a lead contact surface of a mold having a portion by a support pin projecting from a mold on which a hollow portion is not formed, in a state where the lead is contacted. Or, it is assumed that the resin molding is performed in a state in which the lead is brought into contact with the lead contact surface of the mold having the convex portion forming the hollow portion by the support block projecting from the mold on the side where the hollow portion is not formed. And a method for manufacturing a hollow plastic package. Another object of the present invention is to provide a method of manufacturing a hollow plastic package, wherein a hole or a groove formed by a support pin and a support block is filled with a resin in a later step and closed.

[0007]

Embodiment 1 Next, an embodiment will be described in detail with reference to the drawings. FIG. 5 shows the concept of the method for manufacturing a hollow plastic package according to the present invention. D1 is an upper mold, and D2 is a thermosetting resin which is heated to a temperature at which the thermosetting resin can be melted and thermoset. A protrusion 6 for forming the hollow portion 2 of the hollow package is provided on the upper die D1.
Is provided. Into the pot 3 of the lower mold D2, a thermosetting resin tablet R such as an epoxy resin is charged in advance.

A lead frame LF serving as a lead electrode is held between the upper die D1 and the lower die D2. The lower die D2 has a support pin P which is slidable up and down at a position corresponding to the upper die contact surface S2 of the lead frame LF.
Are installed for the number of leads, and the lead frame LF is placed on the upper die D1.
At a predetermined pressure.

The support pin P has a tapered shape so that the adhesive between the hollow package and the support pin is easily broken when the support pin is removed after molding. The thermosetting resin R charged into the pot 3 is heat-melted in a high-temperature mold, and the plunger 4 is raised from that state to move the resin R through the runner 5 into the cavities C1 and C2. And filling by pressure. After a predetermined heat curing time, the upper and lower molds are separated and the support pins are
2. Retract downward from 2, and finally take out the molded product.

According to the above steps, the lead frame LF
Is filled with the resin pressed against the upper die contact surface S2 by the support pin P, so that the molten resin can enter between the lead frame LF and the upper die contact surface S2. Disappears. Therefore, the problem that the resin enters between the upper die lead contact surface and the lead frame LF and is molded in a state where the lead is not exposed to the hollow portion as a result is eliminated.

[0011]

Second Embodiment FIG. 7 shows a method of manufacturing a hollow plastic package according to a second embodiment of the present invention.
In the present embodiment, in addition to the support pin P being slidable up and down and being insertable / removable in the above-described embodiment 1, the support pin itself is rotated during the pulling operation.

Therefore, the adhesion between the support pin and the molded hollow package can be more easily released. According to the method of this embodiment, it is possible to minimize the stress applied to the hollow package during the operation of pulling out the support pins.

[0013]

Third Embodiment FIG. 8 shows a method of manufacturing a hollow plastic package according to a third embodiment of the present invention.
Instead of the support pins P in the method of manufacturing the hollow plastic package of the first and second embodiments, the support frame B formed integrally with the lower die D2 connects the lead frame LF to the upper die contact surface of the upper die D1. It is configured to be pressed in S2.

By changing the relative height between the outer lead gripping surface S1 and the upper lead contact surface S2 of the upper die D1, the lead frame LF is pressed against the upper die lead contact surface S2 of the upper die D1. Set the pressure to apply.

According to the method of the present embodiment, the first embodiment is used.
The method of manufacturing the hollow plastic package according to the second embodiment requires a complicated drive mechanism for the support pins P in the lower mold, whereas the support block B is integrally formed with the lower mold D2. In addition to the advantages of the method of manufacturing the hollow plastic package according to the first and second embodiments, the mold can be easily manufactured and the cost can be reduced.

[0016]

Fourth Embodiment FIG. 10 is a plan view of the back side of a hollow plastic package obtained by the method for manufacturing a hollow plastic package of the first embodiment. FIG. 11 is a plan view of the back side of the hollow plastic package obtained by the method of manufacturing the hollow plastic package of the second embodiment. In the hollow plastic package obtained by any of the methods, holes H or grooves T are formed in portions corresponding to the support pins and the support blocks, and the inner leads are exposed. Since the exposed portion Li of the inner lead is close to a hollow portion where a CCD chip or the like is to be mounted later, a problem may occur in moisture resistance. Then, as shown in FIG. 12, if the resin R2 is dropped and filled into the hole H or the groove T on the back surface of the hollow package and is buried, the moisture resistance is also improved.

According to the present invention, there is provided a method of manufacturing a hollow plastic package for molding a chip mounting portion into a hollow, the method comprising: forming a hollow portion on a lead contact surface of a mold having a convex portion; A method of manufacturing a hollow plastic package, wherein resin molding is performed in a state where leads are abutted by support pins protruding from a mold, or a lead contact surface of a mold having a convex portion forming a hollow portion. Conventionally, by using a method of manufacturing a hollow plastic package, in which resin molding is performed in a state in which leads are brought into contact with a support block protruding from a mold on a side where a hollow portion is not formed, a hollow according to a conventional technique is used. Failure due to the plastic package manufacturing method, that is, due to the lead's own weight or the downward pressure of the flowing resin, When the resin is filled in this state, the resin enters between the contact surface and the lead, and as a result, the lead is not exposed in the hollow part. In addition to the inconvenience that the inner lead is sagged due to its own weight, if the lead is held by the upper and lower molds and the upper and lower molds are misaligned, stress is transmitted to the inner lead due to the misalignment. Distortion occurs,
The level cannot be maintained, the tip does not adhere to the contact surface of the upper mold, and when resin is filled in this state, the resin enters between the contact surface and the lead as in the above case, Since the problem that the leads are molded in a state where the leads are not exposed to the hollow portion is completely eliminated, the hollow package obtained by the method for manufacturing a hollow plastic package according to the present invention has all the leads exposed to the hollow portion exposed surface. It is.

Further, by filling the holes or grooves formed by the support pins or the support blocks with resin, it becomes possible to improve the moisture resistance.

[0018]

[Brief description of the drawings]

Fig. 1 External view of hollow plastic package

FIG. 2 is an explanatory view of a method of manufacturing a hollow plastic package according to a conventional technique.

FIG. 3 is a partial perspective plan view of a hollow plastic package.

FIG. 4 is an explanatory view of a method of manufacturing a hollow plastic package according to a conventional technique.

FIG. 5 is an explanatory diagram of a method for manufacturing a hollow plastic package according to Embodiment 1 of the present invention.

FIG. 6 is an explanatory diagram of a method for manufacturing a hollow plastic package according to the first embodiment of the present invention.

FIG. 7 is an explanatory view of a method of manufacturing a hollow plastic package according to Embodiment 2 of the present invention.

FIG. 8 is an explanatory view of a method for manufacturing a hollow plastic package according to Embodiment 3 of the present invention.

FIG. 9 is an explanatory view of a method of manufacturing a hollow plastic package according to Embodiment 3 of the present invention.

FIG. 10 is a plan view of the back surface of the hollow plastic package obtained by the method of manufacturing a hollow plastic package according to the first and second embodiments of the present invention.

FIG. 11 is a rear plan view of a hollow plastic package obtained by the method of manufacturing a hollow plastic package according to the third embodiment of the present invention.

FIG. 12 is an illustration of a method for manufacturing a hollow plastic package according to Embodiment 4 of the present invention.

[Explanation of symbols]

 PKG ... hollow plastic package L ... lead L1 ... lead L2 ... lead L3 ... lead L4 ... lead S1 ... upper outer lead gripping surface S2 ... upper lead contact surface S3 ... L4 lead gripping surface D1 ... upper die D2 ... lower Mold C1 ... Upper mold cavity C2 ... Lower mold cavity R ... Thermosetting resin R2 ... Filling resin P ... Support pin B ... Support block LF ... Lead frame Li ... Inner lead exposed part H ... Hole T ... Groove 1 ... Lead 2 ... Hollow part 3 ... Pot 4 ... Plunger 5 ... Runner 6 ... Protrusion

Claims (8)

[Claims] 1. A method of manufacturing a hollow plastic package in which a chip mounting portion is molded into a hollow, wherein a die having a hollow portion is not formed on a lead contact surface of a die having a convex portion forming a hollow portion. A method for manufacturing a hollow plastic package, wherein resin molding is performed in a state in which leads are brought into contact with support pins that project more. 2. A support pin for contacting a lead with a lead contact surface of a mold having a convex portion forming a hollow portion is a movable pin which can be more freely removed than a mold on a side not forming a hollow portion. The method for manufacturing a hollow plastic package according to claim 1, wherein: 3. A support pin for contacting a lead with a lead contact surface of a mold having a convex portion forming a hollow portion is a movable pin that is more rotatable than a mold on a side not forming a hollow portion. The method for manufacturing a hollow plastic package according to claim 1, wherein: 4. A support pin for contacting a lead with a lead contact surface of a mold having a convex portion forming a hollow portion is a movable pin that is freely rotatable with respect to a mold on which a hollow portion is not formed. The method for manufacturing a hollow plastic package according to claim 1, wherein: 5. A support pin for contacting a lead with a lead contact surface of a mold having a convex portion forming a hollow portion, wherein the support pin is provided in a direction from the bottom surface of the mold having no hollow portion to the lead contact surface. 2. The method according to claim 1, wherein the tapered shape is a tapered conical taper or a pyramid taper. 6. A method of manufacturing a hollow plastic package in which a chip mounting portion is molded into a hollow, wherein a die having a hollow portion is not formed on a lead contact surface of a die having a convex portion forming a hollow portion. A method of manufacturing a hollow plastic package, wherein resin molding is performed in a state where leads are brought into contact with a support block that projects further. 7. A support block for contacting a lead with a lead contact surface of a mold having a convex portion forming a hollow portion,
7. The method of manufacturing a hollow plastic package according to claim 6, wherein the tapered shape is tapered in a direction from the bottom surface of the mold on which the hollow portion is not formed to the lead contact surface. 8. A hollow plastic package obtained by the method according to claim 1, wherein holes or grooves formed by support pins or support blocks are filled with resin in a later step and closed. Method of manufacturing a hollow plastic package.