Fig. 1. (a) Schematic of forward lithography. (b) Reflection from and transmission through a stratified medium.
Fig. 2. (a) EPE measurement illustration. (b) Numerical superposition region. (c) Pattern edge set (PES). (d) Edges of target pattern in Fig. 4(c).
Fig. 3. PV Band demonstration. (a)–(c) Printed images under different process conditions. (d) Computed PV Band. (e) PV Band of the printed images with in Fig. 4(c) illuminated by the annular source in Fig. 4(a).
Fig. 4. (a) Annular source with and . (b), (c) The desired target patterns , .
Fig. 5. Printed wafer images with (a) PE 4494 and (d) PE 5193, EPE images with (b) EPE 1158 and (e) EPE 1512, PV Band images with (c) PV Band 2347 and (f) PV Band 3965 with respect to target patterns and illuminated by the annular source in Fig. 4(a).
Fig. 6. Simulation results with as the target pattern. Columns from left to right: the synthesized source pattern , the synthesized mask pattern , the EPE images, and the PV Band images illuminating by . Rows: proposed approach (a) with and (b) with , SGD (c) with and (d) with .
Fig. 7. Randomly initialized masks within the range ; (a) and (b) . (c) and (d) are the transformed parameters.
Fig. 8. Simulation results with and as the target pattern and weight . Rows: (a) and (c) proposed approach with and , (b) and (d) SGD with and as initial masks.
Fig. 9. Convergence of (a) , (b) of the simulations in Fig. 8, (c) of the simulations in Figs. 8(a) and 8(b), and (d) of the simulations in Figs. 8(c) and 8(d).