Threshold Switching in Te-SbO Films for the Selection Device of Crossbar Resistive Memory Applications

Threshold switching (TS) of a Te–SbO film with high thermal stability up to 300°C and DC endurance over 200 cycles was achieved. Te atoms in both as-deposited and annealed films exist as separate nanocrystalline clusters. The SbO matrix formed in the amorphous phase and most of the Te was the metallic phase. Amorphous Te formed between Te nanocrystallites during electroforming was presumed to act as a conduction path, inducing TS. Formation of amorphous Te in the conduction path can be explained by electric-field-driven drift of Te from the Te nanoclusters when a high field is applied during electroforming.