Nanoscale Electromolecular Lithography (NEL) Wolfgang Borchardt February 13, 2008
UC Berkeley, Mervin Ye Zhou2 Prof. Chang-Hasnain’s group Short Introduction to NEL New technique, proposed in 2005 by W. Shen, Y. Chen and Q. Pei (UCLA) Nanoscale patterning of resists by using an electric mask mask: metal patterns on an insulative substrate (e.g. glass) Nanoscale metal patterns fabricated by e-beam and optical lithography or self-assembly electrochemical polymerization in a water solution with 0.2 M pyrrole monomers and 0.15 M KCl voltage pulse with an amplitude of +1.0 V and a duration of 60 s Wolfgang Borchardt Sources: NSF Nanoscale Science and Engineering Grantees Conference, Dec 12-15, 2005 Nanoscale Electromolecular Lithography (NEL) by Yong Chen… APPLIED PHYSICS LETTERS 87, Electric lithography by electrochemical polymerization by W. Shen,Y. Chen and Q. Pei, UCLA
UC Berkeley, Mervin Ye Zhou3 Prof. Chang-Hasnain’s group 1st step Wolfgang Borchardt Mask Resist Substrate Electrode Insulator Electrode
UC Berkeley, Mervin Ye Zhou4 Prof. Chang-Hasnain’s group 2nd step Wolfgang Borchardt Electrode Insulator Electrode
UC Berkeley, Mervin Ye Zhou5 Prof. Chang-Hasnain’s group 3rd step Wolfgang Borchardt
UC Berkeley, Mervin Ye Zhou6 Prof. Chang-Hasnain’s group 4th step Wolfgang Borchardt
UC Berkeley, Mervin Ye Zhou7 Prof. Chang-Hasnain’s group Results Wolfgang Borchardt b) Selectively transferred lines a) Linearly patterned mask c) AFM image: constant voltage applied with different durations Left: SEM image of nanowire patterns Right: AFM image of nano dot patterns
UC Berkeley, Mervin Ye Zhou8 Prof. Chang-Hasnain’s group Sub-10nm resolution? Two classes of resists (1) Traditional Self-assembled monolayers (SAMs): Reengineering: exposure of useful chemical functional groups topographical changes Wolfgang Borchardt (2) Highly crosslinked 2D-arrays: self-assembled onto electrode surfaces into simple patterns EC-field will break crosslinks „Carving out“ of nanometer-scale regions
UC Berkeley, Mervin Ye Zhou9 Prof. Chang-Hasnain’s group Advantages / Disadvantages + High-throughput => mass production + Scalable + Reliable / robust + Reduced defect density and improved yield in comparison with the 3D mold and mechanical process used in nanoscale imprint lithography - Low resolution (>300nm) until now - Nobody else reporting on this topic Wolfgang Borchardt
UC Berkeley, Mervin Ye Zhou10 Prof. Chang-Hasnain’s group Questions Wolfgang Borchardt