Nanopatterned Stamp Fabrication for Metal-Assisted Chemical Imprinting of Silicon

A. Sharstniou, S. Niauzorau, M. Gregory, B. Azeredo
ARIZONA STATE UNIVERSITY,
United States

Keywords: mac-imprinting, etching, replica molding, soft lithography

Summary:

Metal-assisted chemical imprinting (Mac-imprint) has been demonstrated to selectively etch semiconductors forming complex three-dimensional patterns with resolution defined by the stamp and composition of etchant mixture. Resolution downscaling requires complex serial patterning techniques for stamp production which decrease throughput and increase manufacturing costs. Moreover, the overall cost of Mac-imprint also depends on stamp lifetimes which have not been determined. In this paper, we have implemented nanoimprinting of photoresist films by polydimethylsiloxane (PDMS) molds as a way to easily replicate stamps for Mac-imprint and reduce its costs. Such approach can produce up to 100 stamps from a single PDMS mold without significant degradation of the stamp’s features. Specifically, prepatterned silicon master mold with periodic 450 nm wide and 200 nm height features, was replicated using PDMS mold and then nanoimprinted onto a polymeric film spun onto a silicon chip to generate working stamps for Mac-imprinting.