Development of a nondeforming chucking technique for EUV lithography

- A nondeforming chucking technique for EUV lithography has been developed.
- Temperature distribution and shear and tension forces during freezing were calculated by FEM.
- Shear strength of 0.2 N per pin and tensile strength of 0.34 N per pin, and solidification deformation below ±0.15 μm were measured.
- The new freezing pin chuck has the pitch of 2 mm and are cooled with coolant of 5 °C.
- The new chuck can clamp the low expansion glass mask without deformation at temperatures below 50 °C.