Room Temperature Electroplated Copper Recrystallization: In-Situ Mapping on 200/300 mm Patterned Wafers

The recrystallization kinetics of electroplated copper at room temperature was studied with a novel X‐ray diffraction (XRD) metrology tool. The relaxation of short‐range strains, grain growth, and the evolution of crystallographic texture (preferred orientation of grains) may be monitored in‐situ across a 200 or 300 mm patterned wafer with a spatial resolution ranging from 50 μm to 4 mm. The instrument provides for rapid and automated studies of the effects of deposition parameters of liners and copper seed layers (gas flow, pressure, temperature), liner type, and electroplating conditions (current density, rotational speed, bath chemistry) on recrystallization kinetics of sputtered and electroplated copper. The results are useful in developing and optimizing the deposition and annealing processes. A particular example includes the study of room temperature recrystallization kinetics of electroplated copper on of Ta and TaN/Ta type liners.