Anshuman Cherala

Nanoscale magnification and shape control system for precision overlay in jet and flash imprint lithography

Jet and flash imprint lithography steppers have demonstrated unprecedented capability for patterning of sub-25-nm features for semiconductor manufacturing. A critical requirement for such patterning is the ability to overlay one layer of a device to a previously printed layer. In this paper, the design and development of a nanoprecision mask magnification/shape control system (MSCS) for the unique requirements of imprint-based overlay is presented. Imprint specific topics such as in-liquid overlay and distortions, and on-tool overlay metrology are discussed. The MSCS presented here has demonstrated 10-nm mix and match overlay (mean + 3 sigma) capability that approaches performance of state-of-the-art photolithography tools.