Physics (Internal)

Pushing the Limits of Nanofabrication: Using Micromachines to Assemble Nanostructures

This event is part of the Departmental Seminars.

Dissertation Committee: David Bishop, Shyam Erramilli, Steve Ahlen, Pankaj Mehta

Abstract:

In this talk I will discuss the concept of a "Fab on a Chip" where we construct a palette of MEMS-based micron scale tools to create nanoscale structures. We've built lithography tools, novel atomic deposition sources, atomic mass sensors, thermometers, heaters, shutters and interconnect technologies that allow us to precisely fabricate nanoscale devices and structures using these micron scale devices. I will showcase the power of the technique by discussing a series of experiments on quench condensed superconducting Pb films where we are able to gently place atoms upon a surface, creating a uniform, disordered amorphous film and precisely tune the superconducting properties. Conventional deposition techniques produce films where the metal "balls up" and superconductivity occurs because of Josephson tunneling between the metallic regions. Because our technique places atoms on the surface in a tunable manner with very little substrate heating, the atoms appear to stay put where they land upon the substrate and we can obtain a very different film morphology with much smaller grain size than conventional method. I will discuss how this new set of techniques for nanofabrication will open up an unexplored regime for the study of the physics of devices and structures with small numbers of atoms.