Optical properties of metal nanoparticles depend strongly on size and shape. Controlling these parameters implies improving the control of their optical properties. Metal nanoparticles find applications in photonics, biological labeling and catalysis. A number of metal nanoparticles can be fabricated within a narrow size distribution and shape through solution-phase methods. We describe the growth of Ag cubes of uniform size (70nm) and self-assembled into two dimensional arrays by direct high vacuum evaporation and find that the formation of the Ag cubes depends on the substrate composition. This indicates that heat dissipation plays the major role for the formation of Ag cubes on the substrate. While evaporation on native SiO2 on a Si waver leads to the formation of flat islands, the evaporation on thick SiO2 on Ag/Si substrate leads to the formation of oriented Ag cubes of narrow size distribution. We present scanning force, reflection-collection optical scanning probe microscopy and SEM images and discuss the shape selective growth of Ag nanoparticles.
Journal: TechConnect Briefs
Volume: 1, Technical Proceedings of the 2006 NSTI Nanotechnology Conference and Trade Show, Volume 1
Published: May 7, 2006
Pages: 329 - 331
Industry sector: Advanced Materials & Manufacturing
Topics: Nanoparticle Synthesis & Applications