Pre-breakdown in thin SiO2 films

The on-off fluctuations of the tunnel current in 5.6 nm SiO2 films before d ielectric breakdown are analyzed in detail. For this purpose, a low noise m easurement system has been realized which allows detecting the pre-breakdow n phenomena and interrupting the stress before the catastrophic failure occ urs. A spectral analysis of these fluctuations is presented along with the preliminary results of the experiments made possible, for the first time, b y the new measurement system.