Although Sb2Te3, as a candidate material for next-generation memory devices, has attractive properties such as higher operation speed and lower power consumption than Ge2Sb2Te5, its poor stability prevents its application to commercial memory devices. Transition metal dopants provide enhancements in its phase change characteristics, improving both thermal stability and operation energy. However, the enhancement mechanism remains to be sufficiently investigated, and standard properties need to be achieved. Herein, the phase change properties of Sb2Te3 are confirmed to be enhanced by the incorporation of a heavy transition metal element such as Ag. The crystallization temperature increases by nearly 40%, and the operation energy is reduced by approximately 60%. These enhancements are associated with the changes in the local Sb2Te3 structure caused by Ag incorporation. As the incorporated Ag atoms substitute Sb in the Sb-Te octahedron, this turns into a Ag-Te defective tetrahedron with a strong Ag-Te bond that induces distortion in the crystal lattice. The formation of this bond is attributed to the electron configuration of Ag and its fully filled d orbital. Thus, Ag-doped Sb2Te3 is a promising candidate for practical phase change memory devices with high stability and high operation speed.
|Number of pages||10|
|Journal||ACS Applied Materials and Interfaces|
|Publication status||Published - 2020 Aug 19|
Bibliographical noteFunding Information:
This research was supported by the Nano Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2016M3A7B4910398) and the Ministry of Trade, Industry & Energy (MOTIE) in Korea (Project No. 10080625) and Korea Semiconductor Research Consortium (KSRC) through a project for developing source technologies for future semiconductor devices.
Copyright © 2020 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Materials Science(all)