Improvement of the thermal efficiency of Ge 2 Sb 2 Te 5 -based device by ultrathin carbon nanolayers

In phase-change memory, heat dissipation towards the electrode is an important obstacle to energy efficiency. Low crystalline resistance requires a higher Joule heat for the RESET operation, and a high current density is required. In this study, Ge 2 Sb 2 Te 5 (GST) and C super-lattice-like (SLL) films were proposed to reduce power consumption. The 0.3 nm ultrathin C nanolayers led to a relatively low phase change temperature compared with the pure GST. The periodically deposited C nanolayer can act as an ideal thermal barrier and heat source in the SLL film-based device. The grain growth of GST was confined by the carbon layers, indicating a confined heat diffusion. To investigate the heat distribution in the SLL-film-based device cell, we performed two-dimensional finite element analysis. Because of scattering effect, a higher thermal efficiency in the active region can be expected. In the device performance test, a highly reduced SET/SESET plus was observed in the device. Fabricating an ultrathin C nanolayer is an excellent solution for reducing the power consumption of the device.