Enabling Large-Area Selective Deposition on Metal-Dielectric Patterns using Polymer Brush Deactivation

Abstract

Area-selective deposition could be an important self-aligning material-deposition technique to enable future nanoelectronics by accurately placing active materials at previously defined substrate patterns. We describe a robust self-aligning strategy to pattern uniform gold (Au) thin films on only the dielectric areas of prepatterned copper/silicon dioxide (Cu/SiO2) substrates. The use of an amine-terminated polystyrene polymer brush (i.e., PS-NH2) to selectively block micrometer Cu regions of patterned Cu/SiO2 substrates is demonstrated. Following thermal evaporation of ∼35 nm thick Au films on PS-NH2 modified Cu/SiO2 surfaces and subsequent acetic acid etching, large-area selective patterning of Au films on SiO2 regions was achieved. We evaluated the influence of the initial PS-NH2 polymer brush film concentration and etching conditions to optimize the process window for the demonstration of highly successful area-selective deposition on SiO2 surface regions. X-ray photoelectron spectroscopy and scanning...