Nitrogen Incorporation on the Crystallization Temperature of Silver-Doped Ge[sub 45]Te[sub 55] Solid-Electrolyte Films for PMC Memory Applications

Abstract

A programmable metallization cell (PMC) memory structure with silver-saturated GeTe solid-electrolyte films doped by nitrogen was prepared on a TiW bottom electrode by a cosputtering technique at room temperature. The Ge 45 Te 55 solid-electrolyte films deposited with various N 2 /Ar flow ratios showed an increase of crystallization temperature and especially, the electrolyte films deposited at N 2 /Ar ratios above 30% showed a crystallization temperature above 400°C, resulting in survival of a back-end process in semiconductor memory devices. A PMC memory device with nitrogen-doped Ge 45 Te 55 solid electrolytes shows reproducible memory characteristics based on resistive switching at threshold voltage of 1.2 V with high R off /R on ratios.