Demcon Focal has the capabilities to design, deliver and qualify one of the most demanding precision optical assemblies: a lithography lens. Demcon is using state-of-the-art alignment tooling and cleanroom facilities to achieve diffraction limited imaging for a large field of view. We have designed a lithography lens with high NA and large field of view that is capable of imaging semiconductor structures on wafers to produce e.g. processors, LEDs, MEMS, USB memory, etc.

Project specifications

• Magnification 5x (0.2x)
• Telecentric on image side
• Field-of-View 22 x 22 mm
• Diff limited
• Critical dimensions < 0.4 μm (NA > 0.5)
• High critical dimensions uniformity (< 2%)
• Useable Depth-of-Field ~ 1 μm
• Distortion < 100 nm (maximum over field)
• Magnification needs to be adjustable using back-focus
• Order of magnitude 10 ppm
• Magnification and focus changes due to short term temperature change as small as possible
• Temperature stability within +/- 0.1 degree Celsius
• Magnification and focus deviations due to pressure change are compensated using focus and back-focus only