Project Details
Projekt
Novel metallic and semiconductor nanorod/nanowire architectures
Applicant
Professor Dr. Michael Giersig
Subject Area
Condensed Matter Physics
Term
from 2004 to 2006
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 5428602
The focus of this project is a detailed study of novel semiconductor and metallic nanorod architectures in order to gain a better understanding of the growing process and difference in properties to those of the bulk materials. Epitaxially grown single-crystalline semiconductor nanorods and periodic nanorod arrays can be realized by use of nanostructured substrates. The formation of monolayers of self-assembled colloidal particles (mainly polystyrene submicron-sized, monodisperse spheres) is well-established and widely used in various fields of research. Nanosphere lithography (NSL), will be used for the creation of periodic and quasiperiodic self assembly spherical objects like polystyrene or silica particles with a diameter in the range of 200 to 2000 nm. The two and three-dimensional (2-D, 3-D) ordered particles will be used as a mask for the following deposition of various amounts of different metals. After the evaporation process the liftoff of the mask will be performed. The metallic 2-D and 3-D varying particle arrays permit the control of the distance between the nanotubes as well as their cubic, hexagonal or more complicated ordering. The final nanotubes grown on nanostructured substrates will be done by plasma enhanced chemical vapor deposition. The amount of catalyst deposited through the mask can determine the thickness of growing nanotubes with can in turn directly influence their optical and electronic properties. Wet chemical synthesis of nanorods and nanowires has been done by surfactant directed aggregation/coalescence of - or epitaxial growth on 2-5nm seed particles. The growing mechanisms involved are in most cases still unknown; the elucidation of these growing mechanisms will be a major focus of this project. As one can expect that growing mechanisms differ for different materials such as metals and semiconductors, we will investigate metallic- and bimetallic-, as well as semiconducting nanorods and nanowires. A further focus of this project will be the investigation of the properties of the final materials. Investigations will be done applying UV/VIS- spectroscopy, optical microscopy, atomic force microscopy, transmission electron microscopy, and electron energy loss spectroscopy.
DFG Programme
Priority Programmes
