NEW CONCEPT FOR APPLYING EDGE LINE PHASE-SHIFTING MASKS TO ARBITRARY MASK LAYOUTS

This paper explains the principle of a method which avoids printing of phantom resist lines due to undesired intensity minima appearing on C r-less edge line phase-shifting masks. The method combines principles of grey-tone lithography and attenuated phase-shifting masks to give, what we call, a Cr-Less Attenuated Phase-shifting mask (CLAP). Rules f or generating a CLAP design and a paradigm setup of a CLAP mask are pr esented. The capabilities and possible limitations of the CLAP method based on simulated results for a standard wafer stepper setup using th e SOLID lithography simulator are being assessed.