Phase-change materials were highly promising for next-generation nonvolatile data storagetechnology and their properties were usually improved by doping. In this paper, the pronounced effectsof Sn doping (0%, 10%, 30%) on crystallization behaviors of Ge2Sb2Te5 (GST) film induced by apicosecond pulsed laser were investigated in detail. The TEM observations presented the crystallizationthreshold, melting threshold and ablation threshold all decreased with the increasing of Sn dopingwhile the crystal structure and crystallization behavior has not been changed. After single pulseGaussian laser irradiation, the morphology of crystallized films for GST and Sn-doped GST allpresented an ingot-like microstructure at higher laser fluence and equiaxed crystal microstructure atlower laser fluence, which was mainly caused by the temperature gradient. The local grain refinementwas found in GSTSn30% films because weaker Sn-Te bond (359.8 kJ/mol) replaced the stronger Ge-Tebond (456 kJ/mol), which was also proved by X-ray photoelectron spectroscopy (XPS). This eventuallyled to a decline in nucleation energy barrier and increased nucleation rate.
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