Simulation-based calculations of the proton dose in phase change memory cells

Abstract

Monte Carlo simulations of proton irradiation on phase change memory cells were conducted and the proton dose, in both the whole memory cell and in its active layer, calculated. The memory cell was modeled by a multi-layer stack consisting of two TiW electrodes and ZnS-SiO2 films as insulators surrounding the active region. Materials considered for the active region were Ge2Sb2Te5, AgSbSe2, and Si2Sb2Te5. The effects of exposing phase change memory cells to proton beams were investigated for various thicknesses of phase change materials and different proton energies. Radiation-induced changes in the investigated memory cells are presented, including the accumulation of atomic displacements and the thermal heating of the active region. Possible effects of these changes on cell operation are discussed.