Figure 1

Characteristic electrochemical behavior of a highly doped n-type Si electrode with a 6-nm-thick SiO₂ film in 0.1 M PBS (pH 3). The exposed electrode was 5 × 5 μm² in size. All potentials are referenced to SCE. (a) Consecutive linear sweep voltammograms (20 mV s⁻¹). The first (black) and the second (orange) voltammograms begin at −2 V, while the third (blue) voltammogram begins at −3 V. The fourth voltammogram (red) was obtained after breakdown, as shown in (b). (b) Chronoamperogram conducted between the third and the fourth voltammograms in which the potential was held at −4 V. The current exceeded the measurement limit after breakdown, which occurred after 55 s of elapsed time.