Prefabricated article and methods of maintaining the orientation of parts being bonded thereto

Abstract

Abstract A prefabricated article, for example, a lead frame, is designed to accommodate parts, for example, semiconductor electronic devices and connecting wires therefor, which are bonded to the lead frame with a fusible material, for example, a metal alloy solder. The semiconductor device may be placed on a portion of a planar surface of the lead frame with a solder layer interposed therebetween. The planar surface of the lead frame is formed either with a single continuous groove or moat or a plurality of spaced grooves, forming a boundary around the die-receiving portion of the surface. The walls of the groove contiguous with the die-receiving surface intersect the surface at an angle sufficient to prevent the solder in a molten state from flowing across the boundary by the mechanism of the surface tension of the solder. This prevents the die from becoming disoriented during the bonding operation. Additionally, a pair of spaced terminals or legs of the lead frame are formed with angular projections on predetermined sections thereof which are adapted to receive and support the connecting wires when the wires are formed with similarly angled bends to facilitate the connection of contact pads of the semiconductor device on the supporting surface to the lead frame terminals are legs while maintaining the proper orientation of the wires with respect to the device.

Inventors

• 👤 Frank M Simpson

Bibliographic Details