Nanopatterned assembling of colloidal gold nanoparticles on silicon

A quasi-one-dimensional (quasi-1D) Au nanocolloids array has been fabricate d on silicon by combining the techniques of atomic force microscopy (AFM)-b ased nanooxidation and chemical assembling of colloidal nanoparticles. The silicon substrate, modified with an octadecyltrichlorosilane (OTS) monolaye r, was first subjected to a localized chemical oxidation by using conductiv e AFM to form silicon oxide lines. After further modification of the oxidiz ed region with an aminopropyltriethoxylsilane (APTES) monolayer via selecti ve chemical adsorption, the substrate was exposed to a colloidal suspension of gold for deposition of gold nanoparticles, It is found that the Au nano particles can be selectively immobilized onto the AFM tip-defined amino-ter minating regions of the silicon surface, forming quasi-1D gold nanoparticle arrays. The patterned structure is highly controllable and reproducible, w hich, we believe, will contribute to studies of nanodevices and mesoscopic phenomena.