Results of experimental studies of the stability of metal-oxide-semiconductor (MOS) structures with an oxide thickness of less than 40 Å to the effect of strong, but before breakdown electric fields are analyzed. It turned out, that objects with an ultra-small thickness of SiO2 are much more "submissive" to the field stress – they are more easily damaged by external influences, but they are much more quickly restored to their original state at the room temperature. In the process of the exposure of structures in a strong electric field, additional localized electronic boundary states with a concentration exceeding 1013 cm-2 at the silicon-oxide contact are formed. Recharging of newly formed centers with increasing field voltage certainly ensures the accumulation of an excess charge at the silicon-oxide interface, sharply increasing field in the insulating layer. This phenomenon should have a decisive influence on the change in tunnel current-voltage characteristics of Si-MOS structures after the field stress.
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