Electrochemical Nanoimprint Lithography

Electrochemical Nanoimprint Lithography (ECNL) works directly on semiconductor wafer, free of thermoplastic and photocuring resists, and without any auxiliary process. The principle of ECNL is the spatially confined electrochemical corrosion caused by the contact potential across the metal/semiconductor phase boundaries exposed to electrolyte solution. ECNL has been proved successful in fabricating various functional micro/nanostructures directly on gallium arsenide and silicon wafer. By virtue of photoelectric effect of semiconductors, the corrosion process can be well accelerated, and the ECNL efficiency is improved. The machining accuracy is determined by the diffusion coefficient of the holes and the corrosion rate of the semiconductor (mu = (D-hole/k(corr))(1/2)), which is usually smaller than the Debye length of the space charge layer at the metal/semiconductor phase boundary. Here we would like to report our recent progresses in ECNL.