Exploration of linear and non-linear double exposure techniques by simulation
In this work, a framework for the assessment of different double exposure techniques is laid out. Both the simulation environment and the utilized models, derived from well-established resist models, are discussed. Numerous simulation results are evaluated to investigate strengths and weaknesses of different double exposure approaches. Non-linear superposition techniques are examined in respect of their process performance for both standard and sub 0.25 ktief1 values. In addition to a study of these effects in the scope of basic layouts, an application to interference-assisted lithography (IAL) is proposed and discussed.