| abstract |
The present invention is a method of forming a UBM for flip chip connection of a semiconductor device,n n n Immersing the patterned wafer in a plating solution containing a nickel ion source and a copper ion source, applying a predetermined current density to form a copper layer for connection between the pad and solder bumps of the chip and for stress relaxation, and a current density A method of forming a flip chip connection UBM, comprising the step of forming a nickel-copper alloy layer, which is a diffusion barrier layer between a solder and a pad, is increased.n n n According to the above configuration, the etching process can be omitted while satisfying the conditions of wettability, diffusion prevention function, and low stress required for forming UBM on the patterned wafer, thereby providing a low-cost process method. |