Extraction of Mos Capacitance in Fowler-nordheim Regime Using the Floating Gate Technique

The floating gate technique (FGT) is a very sensitive method to measure very low level leakage currents in MOS capacitors. This indirect technique requires the precise knowledge of the capacitance of the structure under test. We have studied the impact of the capacitance model (classic or quantum) and of polysilicon gate depletion effect. We have shown that for 7.2 nm thin EEPROM tunnel oxides, a classical capacitance-voltage model remains valid. In a second part, we present a new method to extract the apparent MOS capacitance in the FowlerNordheim (FN) injection range of potentials which cannot be obtained by direct quasi-static capacitance measurements. By reference to direct current-voltage measurements, capacitance values at high electric fields are extracted from FGT current measurements.