GHz C-V Characterization Methodology and Its Application for Understanding Polarization Behaviors in High-k Dielectric Films

In this study, we report an ultra-fast C-V (>4 GHz) measurement methodology for characterizing the high-frequency polarization phenomena in high-k dielectric films (HfO2 and Al2O3). It is confirmed that the methodology based on the displacement current measurement could be applied for GHz CV measurements of high-k dielectric films. Both HfO2 and Al2O3 films show a significant permittivity de-crease under GHz frequencies due to the suppression of ionic polarization. It is the first direct observation of separating ionic and electronic polarization in ultra-thin high-k dielectric films, so far. The phenomena found in this study could be very important for understanding relative physical mechanisms in advanced electron devices, such as ferroelectric and analog devices using high-k dielectric films.