A New Charge Pumping Method for Studying the Si-SiO2 Interface

It is shown that, by varying the frequency of the gate signal in charge pumping measurements, the in-depth concentration profile of the traps from the slow to the fast interface traps, can be obtained. A simple model for the extraction of the trap density is derived. Depth trap concentration profiles are recorded from virgin and stressed devices. For the virgin device, the trap concentration in the oxide agree with that measured on state-of-the-art MOS transistors using noise measurements. On virgin and stressed devices, the integration of the depth trap concentration profiles leads to the interface trap densities measured using the conventional charge pumping method.