Fig. 1. Photoresist exposure process and origin of EUV stochastics in different lithography processes

Fig. 2. Differences between traditional and stochastic failures^[5]. (a) Stochastic failures; (b) traditional types of defects

Fig. 3. Scheme showing the radiation chemistry mechanisms of EUV resists^[14-15]

Fig. 4. Absorption cross sections of elements (Z=1‒86) at EUV^[24]

Fig. 5. Line-edge roughness (LER) values after the entire CAR patterning process in low T_g and high T_g^[85]. (a) LER as a function of the protected site ratio f_p when the number of beads N=64; (b) LER as a function of the number of beads N at fixed f_p=0.5; (c) 3D image of residual polymer from (a) for low T_g resist; (d) 3D image of residual polymer from (b) for low T_g resist

Fig. 6. Sequence controlled resists based on polypeptoid ^[86]. (a) Scheme showing monomer structures and polymer sequence; (b) patterns produced from polypeptoid of different sequences under DUV exposure

Fig. 7. Concept and lithographic results of novel functionalized materials^[74]

Fig. 8. Defect analysis for BQ variation^[75]. (a) Total post litho defect density with e-beam; (b) nanobridge defect density; (c) line break defect density

Fig. 9. Process flow of PTD (positive-tone development) and NTI (negative-tone imaging) lithography^[89-90]

Fig. 10. Process windows for line/space between EUV PTD and EUV NTD^[92]

Fig. 11. Distribution of light intensity on high reflective substrate and a baking step smoothens this concentration pattern by diffusion (from the left to the right shows the chronological sequence of a numerical modelling)^[94]

Fig. 12. Simulation results of LCDU (3σ) variation of 20 nm half pitch (HP) dense hole pattern with cluster diameter (same imaging conditions)^[95]

Fig. 13. Schematic of the fully coupled Monte Carlo simulation for calculating reaction distributions in resist films^[120]

Fig. 14. Stochastic effect analysis based on Monte Carlo method^[15,120]_. (a) Monte Carlo simulated photon adsorption (red ball), secondary electron generation (blue ball), and acid-induced deprotection reaction (green dot) in DUV and EUV CAR; (b) probability model of the stochastic effect for statistical analysis

Fig. 15. Framework of the multiscale computation simulation model^[124]. (a) Density functional theory (DFT), molecular dynamics (MD), and finite difference method (FDM) combined computational study of the exposure process of EUV photoresist materials; (b) simulating the effect of PEB time on exposed morphology