Evaluation of plasma-induced charging damage on metal contact process

The evaluation of plasma-induced charging damage in a metal contact process has been studied with a two dimensional Monte-Carlo simulation and related experiments. From the simulation, it is concluded that the linear shrinkage of the design rule possibly evokes exponential plasma-induced charging damage on the gate oxide during the plasma process. We also confirmed the simulation results with the two different experiments, in-situ charge-up monitoring wafers and fully fabricated test wafers. A phase-controlled pulsed inductively coupled plasma is proposed to suppress the plasma-induced charging damage. Preliminary results show that charging damage is strongly suppressed when the phase delay of the bias power to the source power is near to 180 degrees.