Improvement of Radiation Stability of Energy-dependent Storage Devices Based on Chalcogenide Glassy Semiconductors

Abstract

The work is aimed at increasing the radiation resistance of storage devices, which are one of the main elements in the construction of information processing systems.

The proposed structure of a radiation-resistant memory cell, in which a film of a chalcogenide vitreous semiconductor is used as a switching element, and a unipolar transistor serves as a decisive element. The switching element is resistant to radiation, and the radiation stability of a unipolar transistor is several orders of magnitude lower. Therefore, a method for increasing the radiation stability of unipolar transistors is proposed. To eliminate the change in the parameters of unipolar transistors under the action of ionizing radiation on the processes occurring in the subgap layer of the dielectric and at the interface between silicon and silicon dioxide, it helps to accumulate a positive charge in the manufacture of such a transistor, prior to the high-temperature formation of the subgap layer of the dielectric, to conduct the subgap region of the semiconductor substrate ion implantation of fluorine, which diffuses into this layer. In addition, not silicon dioxide, but silicon nitride — Si₃N₄ is used as the sub-barrier layer of the dielectric, which also contributes to an increase in radiation stability.

A physical model of a memory cell based on chalcogenide glassy semiconductors has been developed, and analytical expressions have been proposed to calculate the dependence of the model parameters on the radiation dose.