A pseudo-two-dimensional model of an n-channel MOSFET under the influence of ionizing radiation

Abstract

A pseudo-two-dimensional model has been developed for determining the radiation-induced changes in the characteristics of an n-channel metal-oxide-semiconductor-field-effect transistor (MOSFET) during exposure to ionizing radiation as well as in the post-irradiated condition. The ionizing radiation-induced excess carriers in the semiconductor as well as changes in the interface states and build-up of oxide-trapped charges at Si–SiO2 interface have been incorporated in the basic model equations for analysing the device under exposure to ionizing radiation. A model has been proposed that can examine the behaviour of the device during exposure to ionizing radiation. This model enables one to determine the ID–VD and transfer characteristics of the device by considering the field-dependent mobility of the surface channel in the unirradiated condition, during exposure to ionizing radiation as well as in post-irradiated condition. The results obtained on the basis of the model in the irradiated as well as post-irradiated condition have been compared and contrasted with available experimental and simulated results.