Metallic nanoparticles electron beam lithography

On detailed electrical characteristics of a SET transistor utilizing charging effects on metal nanoclusters were reported by Sato et al. [26]. A self-assembled chain of colloidal gold nanoparticles was connected to metal electrodes, which were formed by electron-beam lithography. The cross-linking of the particles as well as their connection to the electrodes results from a linkage by bifunctional organic molecules, which present the tunnel barriers. 

In the model catalysts described so far, the interparticle distances were more or less random, governed by the separation of substrate defects which control the nucleation and growth process of the metal particles (74,101). The position and separation of metal particles can be controlled accurately by electron beam lithography (EBL) (which has also been used to fabricate model catalysts), but the minimum size of the metal aggregates is currently still approximately lOnm. Figure 3g shows an example of a platinum nanoparticle array on Si02 (mean size 28 nm interparticle separation 200 nm) (53,106,107). 

Common methods for the fabrication of metallic nanoparticle arrays are electron beam lithography, photolithography, laser ablation, colloidal synthesis, electrodeposition and, in recent time, nanosphere lithography for which a monodisperse nanosphere template acts as deposition mask. A review on advances in preparation of nanomaterials with localized plasmon resonance is given in [15]. 

Grunes J, Zhu J, Anderson FA, Somorjai GA (2002) Ethylene hydrogenation over platinum nanoparticle array model catalysts fabricated by electron beam lithography determination of active metal surface area. J Phys Chem B 106 11463-11468... 

In general, there are two strategies to produce metal nanoparticles. One is the so-called bottom-up method, where nanostructures are obtained through assembly of smaller, basic units into larger structures. The other is the top-down method, which starts from bulk material, whose size is decreased during the process. Common top-down techniques include photolithography and electron beam lithography [82,83]. 

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