Metal powder injection molding of copper and copper alloys for microelectronic heat dissipation

Powder injection molding (PIM) has been applied to copper and copper alloys for several years. Many powder and process variants have been demonstrated, and recent work has been directed to applications associated with heat dissipation in electronic systems. This focuses attention on unalloyed copper with high thermal and electrical conductivity and on bronze for aesthetic non-structural uses. This paper provides a brief history of the field and the ensuing rationalization of the powder, process, and properties to the application. Fundamentally, PIM of copper requires a balance between the optimal processing options that deliver the desired properties and the conflicting dictates of low-cost processing. A key to success often is tied to oxygen control in the copper powder.