Preparation and modification of ZnSb-based phase change storage films

Abstract

In this study, the mechanical and electrical properties of Zn–Sb thin films with different Zn contents were focused; the corresponding improvement mechanism is also discussed. It is found that the maximum phase transition temperature of the film is 250 °C when the Zn content is about 50 at%. The crystallization activation energy of the film also reached a maximum of 4.549 eV. The micro-structure analysis result of these annealed films through XRD showed that when the Zn content is less than 50 at.%, the Sb crystallization firstly reduces the amorphous thermal stability of the material, while the film with the highest crystallization activation energy forms the ZnSb phase. Besides, adding N element greatly increases the resistance ratio of the film before and after the phase change and the phase change temperature point, the maximum temperature reaches 265 °C, and the resistance ratio reaches 104 orders of magnitude. The doping of N also increases the density of the deposited film. When the N content is less, some N elements fill the defects caused by physical deposition, increase the density of the film, and increase the phase transition temperature of the film. The N atoms in the film are more likely to bond with Zn when N content is high, forming a Zn–N bond, and even forming a Zn3N2 phase, so that the phase transition temperature of the film is lowered.