Nanowires are formed by self-assembly during growth of rare earth metal silicides on the silicon (001) surface. They have nanometer scale lateral dimension, show metallic conduction, and survive exposure to air after growth in ultra high vacuum (UHV). They can be grown in parallel arrays, or simple crossed grids. Junctions between nanowires of a variety of geometries spontaneously arise. The objective of this project is to fast track the development of epitaxial nanowire junctions as devices. Electrically addressable nanowires and nanowire junctions will be fabricated and evaluated as to their usefulness as nanowire based devices. In particular, the hope is to develop a fully self-assembled device, from the nanometer scale active area all the way to macroscopic contact pads without the need for manipulation of individual elements. The specific goal will be to demonstrate that it is possible to make a fully self-assembled nanowire based device, and to have electrical measurements on at least one such device within the grant period. There are formidable technical hurdles to be surmounted, foremost among which is the fact that all fabrication steps must be compatible with the UHV processing that is dictated by the nanowire growth step. Growth of the nanowires and in-situ atomic resolution studies will be ongoing. Methods for fabricating electrical contacts, both UHV and non-UHV based, will be explored. Electrical measurements will be done ex-situ on both individual nanowires and nanowire junctions, using a combination of liquid helium cryostats and a new cryogenic probing station.
As part of their education and outreach activities, all members involved in developing nanotechnology related teaching materials at different levels that will be appropriate for K-12, as well as undergraduate and graduate education. Concepts for displays suitable for very young schoolchildren will be developed in collaboration with a science museum in Lansing. All of the education and outreach activity is intended to raise the general awareness of nanotechnology at all stages of the educational process. This proposal addresses issues in the area of Nanoscale Structures, Novel Phenomena, and Quantum Control.
