A rigorous analysis of the charge pumping (CP) mechanisms has been proposed recently. Accounting for, in this analysis, traps depth distributions in the direction of the oxide depth, provides a general model for CP. In the case of the conventional Si-SiO2 interface, this allows the CP curves to be simulated in all the experimental conditions. For that, the trap depth concentration profiles measured after assuming tunnelling for the capture of carriers are used. The energy and depth position of the traps entering the CP curves can be determined. A new spectroscopic CP technique is also proposed. It allows the separate investigation of the traps situated at the Si-SiO2 interface and of those located further towards the insulator depth. The traps situated at the Si-SiO2 interface are finally studied.

In this paper and using the charge pumping method, it is shown that in state-of-the-art fully processed MOSFET's the Si-SiO2 interface traps have the same properties as those of the Pb0 center. The question as to whether these defects are Pb0 centers is discussed. Devices using HfO2 as gate dielectric are also studied. In spite of some differences, it is found that the traps at the Si-SiO2 interface in these devices have the same properties as those in state-of-the-art fully processed MOSFET's. These differences are discussed. Finally, a method for extracting the interface trap density from the slope of the charge pumping curves is proposed and applied to the two kinds of devices studied.

A general and reliable model for charge pumping (CP) proposed recently has been extended to trap depth distributions towards oxides depth. The fundamental features concerning the energy and depth region probed at the Si-SiO2 interface and in the direction of oxides depth are presented in the case of the different basic CP curves. The effect of the electric field is accounted for and its impact on the results is discussed. Then, MOSFET's with HfO2 gate dielectric are studied. Trap depth concentration profiles recorded from devices after different technological processes are presented and discussed.

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