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In this study, a modified technique of control current stress to investigation thin gate dielectric of MIS structures is proposed. This technique allows to monitor charge trapping in gate dielectric of MIS structures under high-field and another stress situations (irradiation, plasma, hot carriers, etc.). The technique also may be used for testing thin gate dielectric defects. Unlike simple techniques, for example constant current stress and J-ramp current stress, the proposed method uses a sequence of stress current and measuring current pulses. At the same time, the processes of charging and discharging of the MIS structure capacitance as well as the charge trapping in the gate dielectric are taken into account. Charging of MIS structure from inversion to accumulation modes or back way allows one to retrieve a low frequency capacitive-voltage characteristic. Account charging capacitance of MIS structure and charge trapping in gate dielectric at injective mode lets considerably increase metrological characteristics of this technique and reduce inaccuracies. The models describing the change in the charge state of MIS structures, both in the charge capacity, and in the mode of injection of charge carriers were developed. Using these models let to choose optimal algorithm of current stress and increase measurement accuracy. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The effect of high-field injection-thermal and irradiation treatments on the MIS structures reliability and defect reduction in the nanoscale gate dielectric has been investigated. Injection-thermal treatment (ITT) of MIS structures consisted of high-field electron injection into gate dielectric with the charge of defined value and subsequent parameter stabilization of MIS structures by means of thermal annealing. The MIS structures have been studied using novel techniques of multilevel current stress. Our study shows that the ITT can improve reliability of MIS structures (increase of charge-to-breakdown value) and identify defective structures. The ITT provides structural modification of SiO2 and Si-SiO2 interfaces. It has been shown that the ITT at elevated temperatures can reduce the reliability of MIS devices. Performing ITT at high temperatures leads to decrease of charge-to-breakdown average value in MIS structures. It has been demonstrated that irradiation treatment allows to reduce density of defects in thermal SiO2 films, SiO2 films doped with phosphorus, oxynitride films and as a result to increase reliability of MIS devices. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]