Method of wire bond encapsulation profiling

Abstract

A method for profiling a bead of encapsulant extending along an edge of a die mounted to a supporting structure, by depositing a bead of encapsulant onto wire bonds along the edge of the die, positioning a profiling surface over the die at a predetermined spacing from the die, moving the profiling surface across the bead before the bead of encapsulant has cured to reshape the bead profile and, curing the bead of encapsulant. The invention has found that the encapsulant can be effectively shaped by a profiling surface without stripping the encapsulant from the wire bonds. The normally convex-shaped upper surface of the encapsulant bead can be pushed to one side of the bead with the profiling surface. With a lower encapsulant bead, the active surface can be brought into closer proximity with another surface without making contact. For example, the nozzle array on a printhead IC can be 300 microns to 400 microns from the paper path. By collapsing or flattening the wire bond arcs before applying and profiling a bead of encapsulant, the nozzle array on the printhead IC can be less than 100 microns from the paper path.

Dependencies are inferred from the claim text.