Contrast Evaluation of the SCALPEL GHOST in 100 kV Electron Projection Lithography.

We investigated the essential conditions for the SCALPEL GHOST for fabricating 80 nm devices in 100 kV electron projection lithography (EPL), in terms of the exposure intensity contrast. First, we estimated the energy backscattering coefficient, η, and the used resist contrast to be 0.76 and 23% by calculation and experiment at 50 kV. Then, using the obtained parameters and calculated exposure intensity contrast at 100 kV, we found that the SCALPEL GHOST will be applicable, with some resist improvements, when the beam blur of exposure systems, δ, is 45 nm or less.