Guided Self-Assembly of Au Nanocluster Arrays Electronically Coupled to Semiconductor Device Layers

We report the controlled deposition of close-packed monolayer arrays of 5 nm diameter Au clusters within patterned regions on GaAs device layers, thus demonstrating guided self-assembly on a substrate which can provide interesting semiconductor device characteristics. Uniform nanometer scale ordering of the clusters is achieved by a chemical selfassembly process, while micron scale patterning is provided by a soft lithographic technique. Scanning tunneling microscope imaging and current-voltage spectroscopy indicate the Au nanoclusters are strongly coupled electronically into the underlying semiconductor substrate while exhibiting only weak electronic coupling in the lateral plane.