bumpbonding

Bump bonding is a semiconductor fabrication process used to create electrical interconnections between a semiconductor die and a substrate. It is a type of flip-chip technology where solder bumps are formed on the contact pads of the semiconductor die. These bumps are typically made of a solder alloy, such as gold-tin or tin-lead, and are deposited using techniques like electroplating or evaporation.

Once the solder bumps are formed on the die, the die is flipped over and aligned with corresponding pads on a substrate, which can be a printed circuit board or another integrated circuit. The die is then pressed into contact with the substrate, and heat is applied to melt the solder bumps. This reflow process creates a metallurgical bond between the die and the substrate, forming the electrical connections.

Bump bonding offers several advantages. It allows for a higher density of interconnections compared to wire bonding, as the bumps are directly placed on the pads. This also leads to shorter and thicker interconnects, which can improve electrical performance by reducing inductance and resistance. The flip-chip nature of bump bonding also allows for better thermal dissipation from the die to the substrate. It is widely used in high-performance applications such as microprocessors, GPUs, and memory devices.