Wafer Bumping

Wafer bumping forms microscopic solder bumps on wafer surfaces to serve as conductive paths for subsequent chip interconnection. With ultra-fine bump dimensions and high array density, the process demands exceptional uniformity, cleanliness and profile consistency of solder materials. It is an essential pre-process for Flip-Chip interconnection, and bump quality directly determines subsequent bonding yield, electrical connectivity and long-term device reliability.

Industry Challenges & Solutions

Wafer bumping is vulnerable to non-uniform bump height, poor wetting, oxidation, bridging, voids and surface residual contamination. Tiny defects can be amplified during subsequent flip-chip bonding and result in batch failures. 

Huaqing supplies high-purity solder pastes and dedicated low-residue fluxes optimized for wafer bumping and bump reflow processes. Our materials deliver stable bump profiling while restraining oxidation and bridging, enabling uniform and consistent micro-bump arrays on wafers.