Wafer level bumping technology for high voltage LED packaging

This paper proposed and developed an effective thermal management method for HVLED packaging with wafer level bumping technology. In the HVLED package, multiple thermal bumps were fabricated on HVLED chips to enhance heat dissipation. Cu-Sn-Cu bumps were used. The size, pitch and stand-off height of bumps were optimized for underfill dispensing. Moreover, a high thermal conductivity underfilll was used to further improve the thermal performance of the package.