Study on the influence of γ-ray total dose radiation effect on the electrical properties of the uniaxial strained Si nanometer NMOSFET

Abstract

The carrier microscopic transport process of uniaxial strained Si n-channel metal-oxide semiconductor field-effect transistor (NMOSFET) has been analyzed under γ-ray radiation. The variation of electrical characteristics of the uniaxial strained Si nanometer NMOSFET has also been investigated under the total dose radiation. The Capacitor-Voltage (C-V) and Current-Voltage (I-V) characteristics are measured at room temperature before and after irradiation for each sample. The results indicate that the drift of threshold voltage, the degradation of carrier mobility and the increase in leakage current because of the total dose radiation effect. Moreover, a two-dimensional analytical model of threshold voltage (Vth) and carrier mobility model have been developed due to the total dose irradiation taken into consideration. Based on the model, numerical simulation has been carried out by MATLAB. The influence of the total dose, geometry and physics parameters on threshold voltage was simulated. Moreover, to evaluate the validity of the model, the simulation results were compared with experimental data, and good agreements were confirmed. Thus, the experiment results and proposed model provide good reference for research on irradiation reliability and application of strained integrated circuit of uniaxial strained Si nanometer n-channel metal-oxide semiconductor field-effect transistor.