Hall Mobility in Hafnium Oxide Based MOSFETs: Charge Effects

The Hall effect is used to measure the electron mobility in HfO 2 based n-channel field effect transistors with poly-Si gates. Large deviations between measured Hall and drift mobilities are explained by the presence of high concentrations of nonfixed charge (up to 4 × 10 12 cm-3). Simulated mobility curves show that the observed concentrations of fixed and nonfixed charge can estimate the measured mobility significantly better than if only the fixed charge concentration is used.