|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Recent Advances in Functional Materials and 2D/3D Processing for Sensors, Energy Storage, and Electronic Applications
||Understanding the diminished variabilities in Ag-doped crystalline ZnO based threshold switching selectors for 3D cross-point memory
||Akshay Sahota, Harrison S. Kim, Jaidah Mohan, Yongchan Jung
|On-Site Speaker (Planned)
Ag-based threshold switching (TS) selectors suffer from imminent variability issues, especially variabilities in threshold voltage (Vth) i.e. intercell and cycle-to-cycle shifts. In this work we demonstrate a novel approach to subdue this Vth variability by uniformly doping the selector medium with Ag metal atoms using the RF magnetron sputtering process. Doping the ZnO switching layer restricts the Ag concentration in it, which eventually trims down the stochasticity of the conduction mechanism during filament formation. ZnO when grown as a crystalline film follows anisotropic diffusion which involves lesser randomness due to thermodynamically favorable in-plane Ag migration. Additionally, Ag can migrate only to a few vacant positions in Ag:ZnO matrix limited by the HCP symmetry of ZnO, which ultimately leads to a tighter Vth distribution and thus subdued Vth variability. This can lead to exceedingly reliable TS selectors for high density memory applications like 3D cross-point arrays.