Monte carlo simulation of charging effects in linewidth metrology (II): On insulator substrate

Charging effects have been investigated quantitatively using Monte Carlo (MC) simulation when the linewidth of polymethylmethacrylate (PMMA) insulator patterns on SiO₂ insulator substrate are measured by scanning electron microscope (SEM). We established reference operating and shape conditions for array patterns and we have calculated the offset on linewidth metrology according to the change in each condition. We have used a 50% threshold algorithm for the edge determination, calculated the offsets in those conditions, and compared them with the results in the case of Si substrate. Finally, the question of which factor is the most sensitive in linewidth metrology is discussed.