The fabrication and properties of N-doped Sb₂Te₃ phase-change materials prepared by pulsed laser deposition

Although Sb₂Te₃ (ST) has the merits of fast crystallization speed and low crystallization temperature (132ºC), it cannot be directly used in phase change random access memories due to its high reset voltage. In this study, N-doped ST thin films with different nitrogen concentrations were deposited by pulsed laser deposition (PLD). Atomic force microscopy showed that the surface roughness of as-grown and N-doped ST thin films was 0.12 nm and 0.58 nm, respectively. The N-doped films possesed better component stability, with significantly higher resistivity in the low resistance state and so lower reset voltages. The optimum set and reset voltages were obtained for films with a nitrogen concentration of 6 at%, resulting in lower power consumption and good overall performance.