Fig. 1. Schematic diagrams of self-referencing interferometer alignment measurement. (a) Schematic diagram of optical path of self-referencing interferometer alignment system; (b) schematic diagram of optical path of self-referencing interferometer prism

Fig. 2. Schematic diagram of beam diffraction for ideal alignment mark

Fig. 3. Schematic diagram of beam diffraction for asymmetric alignment mark

Fig. 4. Schematic diagram for layered processing of alignment mark

Fig. 5. Flow chart of APD calculation

Fig. 6. Schematic diagrams of asymmetric deformation marker structure. (a) Top deformation; (b) floor deformation; (c) sidewall deformation

Fig. 7. Effects of layer number on APD and WQ. (a)(b) Top deformation; (c)(d) floor deformation; (e)(f) sidewall deformation

Fig. 8. Effects of top asymmetric deformation on APD and WQ. (a) APD versus Δhtop; (b) WQ versus Δhtop

Fig. 9. Effects of bottom asymmetric deformation on APD and WQ. (a) APD versus Δhfloor; (b) WQ versus Δhfloor

Fig. 10. Effects of sidewall asymmetric deformation on APD and WQ. (a) APD versus Δx; (b) WQ versus Δx

Fig. 11. Effects of grating groove depth on APD and WQ. (a)(b) Top deformation; (c)(d) floor deformation; (e)(f) sidewall deformation

Fig. 12. Effects of duty cycle on APD and WQ. (a)(b) Top deformation; (c)(d) floor deformation; (e)(f) sidewall deformation