focal-showcase-lithography lens design

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.

project specifics

  • 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

"it is all about precision opto-mechanics."

Within Demcon focal we are very proud that we managed to design and realize this masterpiece.