Thesis presented December 21, 2004

Abstract:
Isolated semiconducting nanostructures have the property to confine charges on long time scales. The charge retention depends on several parameters such as the size of the nanostructure, the density and the quality of the interface with the dielectric. We have investigated these properties with an AFM in air with electrostatic force microscopy (EFM). EFM allows injecting charges locally and then probing, with a sensitivity of a few tens of electrons, the individual as well as collective behaviors of nanostructures. We have characterized the non-linear tip-sample interaction for an electrostatic coupling. We then studied the behavior of Si and Ge nanostructures on SiO₂. The saturation of the electron cloud for a network of nanocrystals was evidenced, while kinetic roughening of the electron cloud in a dense network of nanocrystals was observed.

Keywords:
Electrostatic Force Microscopy, non-linear oscillator, approach-retract curves, electrostatic coupling, semiconducting nanostructures, silicon, charge retention, Coulomb blockade, tunnel effect, charge spreading, kinetic roughening

On-line thesis. ​