Picosecond laser pulse-driven crystallization behavior of SiSb phase change memory thin films

Transient phase change crystallization process of SiSb phase change thin films under the irradiation of picosecond (ps) laser pulse was studied using time-resolved reflectivity measurements. The ps laser pulse-crystallized domains were characterized by atomic force microscope, Raman spectra and ellipsometrical spectra measurements. A reflectivity contrast of about 15% can be achieved by ps laser pulse-induced crystallization. A minimum crystallization time of 11 ns was achieved by a low-fluence single ps laser pulse after pre-irradiation. SiSb was shown to be very promising for fast phase change memory applications.

► We reported crystallization dynamics of a novel SiSb phase change material. ► We measured optical constants of as-deposited and irradiated SiSb areas. ► Optical properties of as-deposited and irradiated SiSb thin film were compared. ► Crystallization of irradiated SiSb was confirmed by using AFM and micro-Raman spectra. ► The heat conduction effect of lower metal layer of multi-layer films was studied.