lithography lens design.
Demcon focal has the capabilities to design, deliver and qualify one of the most demanding precision optical assemblies: the lithography lens. Demcon uses state-of-the-art alignment tooling (Opticentric) and cleanroom facilities to achieve diffraction limited imaging for a large field of view. We designed a lithography lens with high NA and large field of view that is capable of imaging semiconductor structures on wafers to produce processors, LEDs, MEMS, USB memory, etc.
- Magnification 5x (0.2x)
- Telecentric on image side
- FOV 22mm x 22 mm
- Diffraction limited
- CD < 0.4um (NA> 0.5)
- High CD uniformity (<2%)
- Useable DOF ~ 1 um
- Distortion < 100nm (maximum over field)
- Magnification needs to be adjustable using back-focus
- Order of magnitude 10 ppm
- Minimize magnification and focus errors due to short term temperature fluctuations within +/-0.1 degree
- Magnification change and focus due to pressure change is compensated using focus and back-focus only