Projection maskless lithography

Abstract

Recent studies have shown the feasibility of Projection Mask-Less Lithography (PML2) for small and medium volume device production (2-5 WPH) for the 45nm technology node. This PML2 tool concept comprises a combined electrostatic-magnetic electron optical column with 200x de-magnification factor. Instead of a mask there is a programmable aperture plate enabling dynamic beam structuring. Wafer exposure is done stripe-by-stripe with a scanning 300mm wafer stage. Detailed calculations of the PML2 optical column (2-step demagnification) including Monte-Carlo simulations of Coulomb interactions are presented. The extendibility of PML2 technology for the 32nm node will be discussed.