Characteristic features of the thermal switching process in chalcogenide vitreous semiconductors

The current and temperature distributions during the thermal switching process in high electric fields exceeding threshold values are investigated using the experimental pulse technique and calculations based on the experimental data obtained for vitreous chalcogenide semiconductors (the vitreous material Tl2Se.As2Te3 is studied as an example). It is shown that in the course of the thermal switching process during the delay time a pronounced localization of the current and high temperature region occurs in a sufficiently narrow channel of the sample. The sharp increase of the total current flowing through the sample under switching itself (the transition to the low-resistance state) is associated with the high-conductive channel expansion till to the formation of a sufficiently wide channel in the on-state. (author)