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The effect of yttrium doping on the phase transition properties and crystal structure of Ge1Sb9 thin films was studied. Y-doped Ge1Sb9 thin films have higher crystallization temperature (218 °C) and data retention capacity (141.2 °C for 10 years), revealing that Y doping improves amorphous thermal stability. X-ray diffraction and X-ray photoelectron spectroscopy analysis show that the addition of yttrium could inhibit grain growth and restrict the grain size due to the formation of amorphous Y and Ge components. X-ray reflectivity results show that yttrium doping results in less volume change, which predicts the enhanced performance stability of the device. A T-shaped phase change memory cell based on the Y0.26(Ge1Sb9)0.74 films exhibits a faster operation speed (100 ns) and lower power consumption (2.4 × 10−10 J) than traditional Ge2Sb2Te5 materials. The results reveal that Y-doped Ge1Sb9 is a phase change memory material with good structural properties and device performance. [ABSTRACT FROM AUTHOR]

In this study, In48.9Sb15.5Te35.6 (IST) was introduced as a stable interlayer to improve the weak amorphous thermal stability and large resistance drift of Sb films. The results showed that Sb atoms tend to bond with In atoms to form In–Sb bonds at the multilayer interfaces, thus improving the thermal stability of multilayer films. Compared with Sb films, Sb/IST had a higher phase transition temperature (∼196 °C) and crystallization activation energy (∼2.23 eV). The surface scratch test revealed that the adhesion of the Sb/IST multilayer film to the substrate was stronger. The separation of the interfaces reduced the phase transition range and made the density change smaller before and after crystallization (∼3.1%). Grain refinement resulted in a decrease in resistance drift and electrostatic potential on the film surface for the Sb/IST film. A phase change memory device based on the Sb/IST multilayer film successfully realized the reversible operation of SET and RESET. The feasibility of the Sb/IST multilayer films as a kind of phase change material with high stability and low resistance drift was verified. [ABSTRACT FROM AUTHOR]

In this paper, the effect of Sb2Se on the phase change characteristics of Ge2Sb2Te5 (GST) is systemically studied for applications in phase-change random access memory (PRAM). The crystallization temperature of Sb2Se–GST increases with increasing Sb2Se content, while the archival life of the amorphous state first decreases and then increases. The phase transition from face-centered-cubic (FCC) to hexagonal (HEX) is suppressed when the Se atomic percentage is higher than 9% for Sb2Se–GST films. The wide band gap and high value of B1/2 lead to a contrast in resistance of about five orders of magnitude between the amorphous and crystalline states. Compared with GST, Ge4Sb52Te9Se35 shows a high crystallization temperature, a wider band gap and a fast switching speed, suggesting it is a potential candidate for PRAM. [ABSTRACT FROM AUTHOR]

In this paper, the effect of Sb2Se on the phase change characteristics of Ge2Sb2Te5 (GST) is systemically studied for applications in phase-change random access memory (PRAM). The crystallization temperature of Sb2Se–GST increases with increasing Sb2Se content, while the archival life of the amorphous state first decreases and then increases. The phase transition from face-centered-cubic (FCC) to hexagonal (HEX) is suppressed when the Se atomic percentage is higher than 9% for Sb2Se–GST films. The wide band gap and high value of B1/2 lead to a contrast in resistance of about five orders of magnitude between the amorphous and crystalline states. Compared with GST, Ge4Sb52Te9Se35 shows a high crystallization temperature, a wider band gap and a fast switching speed, suggesting it is a potential candidate for PRAM. [ABSTRACT FROM AUTHOR]