Modelling the generation of Joule heating in defective thin oxide films

Abstract

Thin oxide films are dominantly used as insulating materials in a wide range of CMOS electronic devices. Continuous scaling, governed by Moores Law, dictates that the thickness of oxides materials could be as thin as a few nanometers. Consequently, a generation of oxide defects, through field-driven and thermal-driven processes, presents a serious reliability challenge. On the other hand, a controllable formation of oxide defects in simple metal-insulator (oxide)-metal devices has recently attracted significant attention for the realization of Resistive RAMs (RRAMs) novel type of non-volatile memory technology that offers a low programming energy [1], a rapid switching [2], and a very high levels of integration [3]. In this paper we model the generating of Joule heating as a result of the current flow through a defective thin oxide layer. We use the representation of resistive network as well as the Fourier Heat Equation to simulate the oxide matrix and the heat flow. Our simulation demonstrates that temperatures generated by the Joule heating can easily reach the value of 900K or more after a few hundred microseconds. Precise control of the current flow timing is the key parameter to prevent the extensive heating and the oxide damage.