Investigation of Thomson Effect in Cu/TaO_x/Pt Resistive Switching Memory

Abstract

Conductive bridge random access memory (CBRAM) shows strong potential for replacing flash memory on the sub-20 nm technology nodes. The switching mechanism is primarily attributed to the electrochemical formation and rupture of conductive filaments. In Cu/TaOx/Pt devices, high electric current in the RESET process can cause significant local heating. Thomson heating effect has to be considered due to conical or cylindrical filament geometries giving cause for strong temperature gradients. The thermoelectric effect is evaluated for the Cu and oxygen vacancy nanofilaments in bipolar and unipolar switching modes. The Thomson coefficient for oxygen vacancy filament is extracted from the difference of SET voltages between two switching modes.