Low-cost power device package with quick-connect terminals and electrically isolated mounting means

DETAILED DESCRIPTION The attainment of the foregoing and other objectives and advantages, is achieved through the present invention wherein a prepackaged semiconductor device having an exposed heat spreader and leads is attached to a lead frame having quick-connect terminals which is then formed, typically by bending, to locate the heat spreader and the quick-connect terminals in predetermined positions.
This formed assembly is surrounded by a molding compound, typically an injection molded insulating plastic, so that the heat spreader is partially exposed on one face of the molded assembly to permit it to be clamped securely against a mount such as a heat sink, and the quick-connect terminals protrude from another face where they can be readily contacted.
The heat spreader must be parallel with and protrude a predetermined distance from the molded package and means are included to facilitate attachment of the completed package to a mount, these means being insulated from any conductive members of the prepackaged semiconductor device.
Further, where the prepackaged device is not internally isolated and where it is required that the heat spreader be electrically isolated from the mount to which it is clamped, a thin insulating layer or external insulating spacer can be used.
The mold compound used for encapsulation of the formed assembly must satisfy certain criteria with respect to strength, plastic flow, thermal stability, coefficient of expansion and compatibility with the semiconductor device.