Study on Direct Current Cu Electroplating in Through Ceramic Holes for High-power LED Packaging

Direct plated copper (DPC) ceramic substrate process has been developed to prepare ceramic substrates for high-power LED packaging. In order to solve the micro through ceramic hole electroplating copper filling problems such as low filling efficiency, and not being able to fill multiple thickness/diameter ratio micro through holes at the same time, this study focuses on optimization of direct current (DC) through hole filling technology. The electroplating solution was optimized by solution electrical conductivity measurement and chronoamperometry. The process parameters such as current density and air agitation flow were determined by observing the electroplating effect of through hole cross section. The optimized DC through ceramic hole filling technology was universal for through ceramic holes with thickness/diameter ratio of 3.33, 4.17, 5 and 6.25. Defect-free plating Cu column with can be obtained at high current density (2ASD), air flow 2L/min and spray water valve half open in 2h.