Electron-Beam Induced Nanomasking for Metal Electrodeposition on Semiconductor Surfaces

The present work investigates the masking effect of carbon contamination patterns deposited by the electron-beam ~E-beam! of a scanning electron microscope ~SEM! for metal electrodeposition reactions. Carbon contamination lines were written at different electron doses on n-type Si~100! surfaces. Subsequently Au was electrochemically deposited from a 1 M KCN 1 0.01 M KAu~CN!2 solution on the E-beam treated surface sites. The carbon masks as well as the Au deposits were characterized by SEM, atomic force microscopy, and scanning Auger electron spectroscopy. We demonstrate that carbon deposits in the order of 1 nm thickness can be sufficient to achieve a negative resist effect, i.e., can block the electrodeposition of Au completely selectively. The lateral resolution of the process is in the sub-100 nm range. The nucleation and growth of Au deposits and their morphology as well as the selectivity and resolution of the process depend on several factors such as the electron dose during masking, and the applied potential and polarization time during Au deposition. The process opens new perspectives for selective electrodeposition, i.e., for high definition patterning of surfaces with a wide range of materials. © 2001 The Electrochemical Society. @DOI: 10.1149/1.1348258# All rights reserved.