Dispersive transport of Hole polarons in MOS-structures after the ionizing irradiation

Abstract

It is shown that the description of the dispersive transport of hole polarons based on the multiple capture model makes it possible to quantitatively describe the kinetics of the accumulation and relaxation of space charge in MOS-structures after ionizing irradiation at low temperatures (80-293 K). Modeling of time dependences of threshold voltage on temperature, electric field strength and gate oxide thickness is carried out. It is shown that the kinetics of space charge relaxation is determined by the hopping transport of hole polarons with the levels of localized states in the range of 0.08-0.55 eV, the concentration of polaron states, the influence of the electric field strength on the average polaron energy, as well as gate oxide thickness on dispersive parameter. The polaron radius is estimated. Keywords: MOS-structure, the ionizing radiation, dispersive transport, polarons, modeling.