Methods to eliminate pattern collapse in mass production by the resist replacement without changing model-based optical-proximity-correction

摘要

Pattern collapse issue was successfully eliminated by the addition of hydrophobic and transparent additives into the resist. The additives form 25 nm-thick layer at the top of the new resist. The layer reduces maximum-tensile-stress acting on resist patterns by 22% due to the hidrophobicity. It was also found that the layer hardly affected the optical-proximity-effect (Difference of thorough-pitch CD: −0.8 ∼ 0.6 nm). As a result, the same OPC could be used without further modification in the OPC model.