Conducting atomic force microscopy studies on local electrical properties of ultrathin SiO films

We have demonstrated the characterizations of the local electrical properties of ultrathin 1–4 nm.SiO2rSi 001. structures using a conducting atomic force microscopy with a nanometer-scale resolution in a vacuum 1=10y5 Pa.. The measurement in a vacuum enables to reduce the influence of adsorbed water on quantitative current measurements, while there is a problem at the measurement in air of 60% humidity. Fitting to the Fowler–Nordheim equation is good at thicker SiO2 films more than ;3 nm. We have also demonstrated the results of continuous current–voltage measurements during the breakdown process by charge injection through a conducting probe. q2000 Elsevier Science B.V. All rights reserved.