High Reliability and Fast-Speed Phase-Change Memory Based on Sb70Se30/SiO2 Multilayer Thin Films
The amorphous-to-crystalline transition was investigatedby in situ temperature-dependent resistance (R-T) measurement using a TP 95 temperature controller (LinkamScientic Instruments Ltd., Surrey, UK) at a heating rate of10°C/min. ?e size of each measured thin lm is 1 cm × 1 cm.?e electrode made up of Si3N4 is set up on the surface of thesample with a diameter of 0.7 μm, and the separation gapbetween two electrodes is 5 mm. ?e activation energy (Ea)and data retention temperature of ten years can be furthergained by measuring the isothermal crystallization curve. ?ebandgap was obtained by measuring the re‘ectivity of thinlms in the range of 400–2500 nm by the NIR spectrophotometer (7100CRT, XINMAO, China). ?e crystallinestructures of the lms were analyzed by X-ray di?raction(XRD, PANalytical, X’PERT Powder). ?e incidence angle θranges from 10° to 30°, and the di?raction patterns were takenin the 2θ range from 20° to 60° using Cu Kα radiation witha scanning step of 0.01°C/min. ?e surface morphology of thelms was examined by atomic force microcopy (AFM,FMNanoview 1000). A picosecond laser pump-probe systemwas used to investigate the phase-change time betweenamorphous and crystalline states, by measuring the re‘ectivity of the material. ?e light source used for irradiating thesamples was a frequency-doubled model-locked neodymiumyttrium aluminum garnet laser operating at 532 nm wavelength at a pulse duration of 30 ps.
Dan Zhang, Yifeng Hu,Haipeng You,Xiaoqin Zhu,Yuemei Sun,Hua Zou and Yan Zheng