Ge2Sb2Te5 nanobelts by femtosecond laser direct writing for resistive switching devices

摘要

One-dimensional Ge2Sb2Te5 (GST) nanobelts crystallized by femtosecond laser writing are used as the electrolyte material in electrochemical metallization cells. The width and roughness of the nanobelts are found to be strongly dependent on the laser fluence. The electrical transport properties of the crystalline GST nanobelts are comprehensively studied. First, the face-centered cubic (fcc) phase dominated crystalline GST nanobelt is demonstrated by the temperature dependence of resistivity results. Second, the decrease of conductance activation energy from 0.41 eV to 0.056 eV reveals a dramatic reduction of the trap potential of GST from amorphous to fcc phase. Finally, the resistive switching based on the electrochemical metallization is obtained in the one-dimension GST nanobelt with the ON/OFF ratio up to similar to 7000, which is hundreds of times higher than that in typical crystalline GST films.