METHOD FOR FORMATION OF SOLDER BUMPS DIRECTLY ONTO ALUMINUM BOND PADS
Original Publication Date: 2000-May-01
Included in the Prior Art Database: 2002-Sep-17
Currently, solder based flip chip bumps on IC bond pads are deposited either by evaporation, plating, thermo-compression bonding (stud bump bonding) or stencil printing (Figure 1). In order to form a robust bond to the aluminum IC bond pad, additional solder wettable layers are added to the IC bond pad e.g. TiW, Au.