Spreading antenna effect of plasma induced charging damage in damascene interconnect process

Electric charge injection mechanism of plasma induced charging damage (PID) in a damascene interconnect process was investigated in detail. In the damascene interconnect process, PID is mainly induced in the deposition processes of Cu diffusion barrier film and inter layer dielectrics (ILD). We found that the antenna area dependence of the PID in the damascene interconnect process is not a simple relation to the top surface area of wiring. Since the charges are injected through the dielectric films on the wiring, effective antenna area which can collect the charges became larger than the area defined by the top surface area of the metal wiring.