| 摘要 |
A plurality of uniform bumps are formed on a semiconductor device by forming a plurality of bond limiting metallization areas. The surface of the semiconductor device is then plated with a plating metal that will be alloyed with the solder of the solder bump, said solder and the plating material forming an alloy during the reflowing step. A mask is then placed onto the surface of the semiconductor device. Openings are made in the mask that correspond to the plurality of bond limiting metallization areas on the surface of the semiconductor device. The plurality of bond limiting metallization areas are also the electrical contact pads. Solder is then deposited through the openings in the mask at a rate of solder deposition which provides a uniform thickness of solder across the surface of the wafer which is later diced into many chips. The openings formed in the mask have substantially a bigger footprint or area associated with each pad. Since the solder balls are at the same height, the solder balls have approximately the same volume. Next, the mask and plating layer beneath the mask are removed leaving a substantially uniform volume of solder and plating material positioned on and near the plurality of bond limiting metallization areas. The next step is to reflow the solder to form substantially uniform solder balls or bumps on each pad across the wafer by consuming the plating metal. The plating material beneath the solder alloys with the solder during this step. In addition, the solder and plating material gathers on each bond limiting metallization area to form bumps which are uniform in height and volume.
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