Numerical Modeling of Thermoelectric Thomson Effect in Phase Change Memory Bridge Structures

Abstract

Phase change memory is a non-volatile memory technology that utilizes the electrical resistivity contrast between resistive amorphous and conductive crystalline phases of phase change materials. These devices operate at high current densities and high temperature gradients which lead to significant thermoelectric effects. We have performed numerical modeling of electrothermal effects in p-type Ge 2 Sb 2 Te 5 phase change memory structures suspended on TiN contact pads using COMSOL Multiphysics. Temperature dependent material parameters are used in the model. Strong asymmetry is observed in temperature profiles in all cases: the hottest spot appears closer to the higher potential end suggesting that the thermal profile can be significantly altered by the thermoelectric effects during device operation. Hence, thermoelectric effects need to be considered for device designs for lower power and higher reliability devices.