ANALYSIS OF TEMPERATURE-DEPENDENCE OF CMOS TRANSISTORS THRESHOLD VOLTAGE

In this paper an investigation of influence of the metal-semiconductor work function difference on the threshold voltage of high-temperature (up to 473 K) operating CMOS transistors, which is often neglected in the literature, is presented. Expressions for temperature dependence of the threshold voltage of both Al-gate and Si-gate CMOS transistors, which take into account the influence of the metal-semiconductor work function difference, are derived starting from the standard expression for the MOS transistor threshold voltage. The temperature coefficient of the threshold voltage is considered in more detail, to provide a simple approximate model for the temperature dependence of the threshold voltage. It is shown that neglecting the temperature dependence of the metal-semiconductor work function difference significantly affects accuracy in prediction of the threshold voltage temperature behavior.