FABRICATION OF QUANTUM DEVICES BY ANGSTROM-LEVEL MANIPULATION OF NANOPARTICLES WITH AN ATOMIC-FORCE MICROSCOPE

We describe a technique for the fabrication of lateral nanometer-scale devices, in which individual metallic nanoparticles are imaged, selec ted and manipulated into a gap between two electrical leads with the t ip of an atomic force microscope. In situ, real-time monitoring of the device characteristics is used to control the positions of the partic les down to atomic accuracy and to tune the electrical propel-ties of the device during fabrication. Using this technique we demonstrate a n anomechanical switch as well as atomic-scale contacts that an stable a t quantized conductance levels on the timescale of hours at room tempe rature. (C) 1998 American Institute of Physics.