JPH0420587Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a mold used for resin molding of semiconductor devices.

[Conventional technology]

FIG. 2 shows the structure of a typical conventional resin molding die.

Molten resin is sent from a pot (not shown) through runner 1 to the cavity (molding part).
The resin is injected through a gate (resin injection port) 3 provided on one side of the resin, and filled into the cavity 2, and the lead frame 4, which has been subjected to die bonding and wire bonding arranged in the cavity 2, is molded with resin.

At this time, an air vent (air escape port) 5 is provided on the side opposite to the gate 2 in order to release air from the area occupied by the injected resin in the cavity 2.

[Problem that the invention attempts to solve]

As mentioned above, the conventional resin molding die has a structure in which the air vent 5 is provided only on the side opposite to the gate 3. Therefore, as shown in FIG. There was a problem in that the air 12 trapped in the resin 11 at the corners of the mold could not escape, and the air 12 would be wrapped in the resin 11 and molded, resulting in voids (bubbles).

This invention was made to solve the above-mentioned problems, and the purpose is to provide a mold that does not generate voids.

[Means for solving problems]

In order to achieve the above object, the resin molding die of this invention extends from the cavity to the gate side of the cavity along the side rail of the lead frame, and has an opening in the space inside the lead frame of the side rail. It is characterized by having a facing air vent.

[Example of idea]

FIG. 1 shows the structure of an embodiment of this invention.

In the figure, 1, 2, 3, and 4 indicate the same or corresponding parts as those indicated by the same reference numerals in Fig. 2, and 4
1 is a side rail of the lead frame 4, and 6 is an air vent provided along the side rail 41 on the gate side.

It is impossible to provide an air vent with a conventional straight structure on the gate side because the runner 1 becomes an obstacle as shown by the dotted line. However, if it is provided along the side rail 41 of the lead frame 4, it is easy to provide a sufficient length as an air vent.

In this structure, most of the air forced into the injected resin comes from the air vent 5 on the opposite side of the gate.
The air that escapes from the air gate 6 and is wrapped in the resin at the corner of the gate side escapes from the air gate 6, so that no air remains in the cavity 2, and no voids are generated.

[Effect of idea]

As described above, according to this invention, voids are not generated in the resin, which greatly contributes to improving the mold yield rate.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the structure of an embodiment of this invention, Fig. 2 is an explanatory diagram showing the structure of a general mold for conventional resin molding, and Fig. 3 is the mold shown in Fig. 2. FIG. 2 is an explanatory diagram showing a state in which the injected resin is spreading into the cavity of the container. 1...Runner, 2...Cavity, 3...Gate, 4...Lead frame, 41...Side rail, 5, 6...Air vent. The same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] In a resin molding mold that has a gate on one side of the cavity, a main air vent on the opposite side, and air vents in multiple directions, the main air vent is provided on the opposite side of the gate side, and the main air vent is provided on the gate side of the cavity. A mold for a resin mold, comprising an air vent extending from a cavity along a side rail of a lead frame and having an opening facing a space inside the lead frame of the side rail.