Programmable metallization cell memory based on Ag-Ge-S and Cu-Ge-S solid electrolytes

Abstract

Programmable metallization cell (PMC) memory is based on the electrochemical growth and removal of nanoscale metallic pathways in thin films of solid electrolyte. Our previous studies concentrated on electrolytes formed from silver-doped germanium selenide glasses but these materials are not able to withstand the temperatures used in standard back-end-of-line processing for the fabrication of CMOS integrated circuits. This paper concerns our more recent work on silver-doped germanium sulfide electrolytes and describes the electrical characteristics of PMC devices made from these materials following annealing at 300 degC and 430 degC. We also present results from devices that use copper in place of silver as this metal is currently used in integrated circuit interconnect