The improvement of endurance characteristics in a superlattice-like material-based phase change device. (1st March 2023)

• Record Type: Journal Article
• Authors: Zheng, Long; Wu, Xiaoqing; Xue, Jianzhong; Zhu, Xiaoqin
• Is Part Of: Semiconductor science and technology. Volume 38:Number 4(2023)
• Publication Date: 2023-03-01
• Subjects: phase change memory -- Ge2Sb2Te5 -- endurance -- superlattice-like film; Semiconductors -- Periodicals; 621.38152
• DOI: 10.1088/1361-6641/acba3c
• Languages: English
• ISSNs: 0268-1242

Abstract

Abstract: Improvement of endurance characteristics has been a hot area of phase-change memoryresearch. The properties of a phase-change material are believed to play an important role in device endurance. Repeated SET–RESET operation always leads to material failure problems, such as composition deviation and phase separation. Moreover, the quality of the electrode and the electrode contact also determine the endurance characteristics. In this study, C nanolayers were periodically inserted into the phase-change material Ge2 Sb2 Te5 (GST) to fabricate a superlattice-like (SLL) structure. Although some of C bonded with some of the Ge, Sb and Te atoms, more C atoms prefer nanometer-scale clusters at the grain boundary in the SLL film. The typical local configuration of GST was unchanged when artificial C nanolayers were inserted. Transmission electron microscopy experiments revealed that the bonded C atoms and nanometer-scale C clusters may occupy the spontaneously created holes and defects, preventing composition deviation of the phase-change material and prolonging the electrode service life. The contact surface between the phase-change material and the electrode is also improved. As a result, we found that the endurance cycle could be improved by up to 10 6 for a GST/C SLL film-based device.