摘要 |
Apparatus and methods of fabricating a bump limiting metallization structure including a two-step bump reflow process that reduces intermetallic compound porosity, increases bump strength, improve die yield, and device reliability. The first step comprises annealing a bump limiting metallurgy and a solder plug at a temperature below the liquidus temperature of the solder plug to form a dense intermetallic compound layer between the solder plug and the bump limiting metallurgy. The second step comprises heating the bump limiting metallurgy and the solder plug at a temperature above the liquidus temperature of the solder plug to form a solder bump.
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