In many electrical devices and systems, an integrated circuit is not directly attached to a circuit board. Rather, the integrated circuit is packaged into a housing to facilitate placing the integrated circuit on the circuit board and to protect the integrated circuit from the environment. The housing must be formed over the integrated circuit without damaging it or any of its associated bond wires. Generally, a packaged integrated circuit is attached to conductive lines on the circuit board of the electrical device or system via exposed contacts (e.g., electrical leads, etc.) on the packaged integrated circuit.
A transfer mold process is used to encapsulate an integrated circuit without damaging the integrated circuit or its associated bond wires. In such a transfer mold process, a mold compound feeder conveys mold compound tablets to a plunger of a mold system. The mold compound tablet may be an epoxy resin, for example. The plunger liquefies the mold compound tablet and injects the liquid mold compound into a mold chase. The mold chase includes a plurality of cells, each of which contains one or more integrated circuits attached to at least one substrate. As the plunger injects the liquid mold compound into the mold chase, the liquid mold compound flows into the cells and encapsulates the integrated circuits contained therein. After encapsulating the integrated circuits, the mold cures and solidifies, thereby encapsulating the integrated circuit in a rigid material to protect the integrated circuits and their bond wires from the environment.
Generally, mold compound tablets are stored in a mold compound supply of the mold system. A mold compound feeder is also included in the mold system to receive mold compound tablets from the mold compound supply. The mold compound feeder conveys the mold compound tablets to the plunger. However, the mold system may experience jams in the devices of the mold system (e.g., a preheater, etc.), creating a need for maintenance and halting the transfer mold process.