Abstract: A mold system for encapsulating substrate-mounted ICs comprises a split mold having a lower cavity adapted for positioning the substrate and an upper cavity adapted for providing a volume space around the IC. The lower cavity is provided with a compressible shim plate adapted to lie on a bottom surface of the lower cavity such that a substrate of a substrate-mounted IC placed in the lower cavity will extend above the upper limit of the lower cavity, which is the split surface of the mold. As the split mold is closed, a lower surface of the upper mold portion encounters first an upper surface of the substrate, then the compressible shim plate is compressed until the mold is fully closed, at which time the lower surface of the upper mold portion is in intimate contact with both the substrate and the upper surface of the lower mold portion. The IC mounted on the substrate is then presented in the upper cavity for encapsulation.

Abstract: A mold is provided for use in encapsulating integrated circuit (IC) dies attached to die attach pads of lead frames, wherein the mold has one or more support elements in cavities of the mold for supporting the die attach pad portions of the lead frame while the mold is closed on the lead frame and encapsulation material is injected to encapsulate the IC dies and die attach pads. The support elements are, in a preferred embodiment, pins extending from the surfaces of the cavities in the mold, and the pins keep the die attach pads from moving into contact with surfaces of the cavities, so die attach pads or dies are not exposed in finished packages. In a preferred embodiment the pins each are tapered in the extended portion, so the amount of exposure of the die attach pad is absolutely minimized. In another embodiment, the support elements are retractable.