Fig. 1. Optical system structure of step-and-scan lithography^[11-16]

Fig. 2. Spatial distribution of top-Gaussian illumination field

Fig. 3. Generation principle of top-Gaussian illumination field

Fig. 4. In traditional illumination mode, the spot intensity distribution formed by a field point of view of the illumination light field on the light field correction plate. (a) Size of defocusing spot formation on the field correction plate; (b) intensity distribution of the defocusing spot on the field correction plate

Fig. 5. Simulation model of optical system for generating the top-Gaussian illumination field

Fig. 6. Illumination light field of three traditional lighting modes. (a) Illumination field 1; (b) illumination field 2; (c) illumination field 3

Fig. 7. Flow chart of transmittance distribution optimization algorithm of light field correction plate based on simulated annealing

Fig. 8. Tendency of E_lost for three illumination fields during optimization. (a) Illumination field 1; (b) illumination field 2; (c) illumination field 3

Fig. 9. Transmittance distributions of three optimized correctors. (a) Corrector 1; (b) corrector 2; (c) corrector 3

Fig. 10. Comparison of the three illumination field intensity in non-scan and scan directions before and after correction. (a) Illumination field 1; (b) illumination field 2; (c) illumination field 3

Fig. 11. Simulation results of three corrected illumination fields. (a) Illumination field 1; (b) illumination field 2; (c) illumination field 3

Table 1. Requirements of the top-Gaussian illumination field

Table 2. Design results of the microlenses of MLAs and diffuser

Table 3. Pitch distributions of the microlenses of MLAs and diffuser

Table 4. Parameters of illumination light field of three traditional lighting modes

Table 5. Parameters and energy loss of the three corrected illumination fields (correction results in non-scan direction)

Table 6. Parameters and energy loss of the three corrected illumination fields (final corrected results)

Table 7. Parameters and energy loss of the three corrected lighting fields (simulation results)