Isotropic and anisotropic scaling analysis of nanowire phase change memory

Abstract

We recently investigated the isotropic scaling properties of nanowire (NW) phase change memory (PCM) [1]. In this paper, we extend our analysis also to anisotropic scaling. By combining electrothermal theory, thermodynamic physics, and numerical simulation, the analysis explains the superiority of NW PCM over conventional thin film PCM, and reveals the different scaling properties of the three widely used operation schemes (constant electric field, constant voltage, and constant current) of NW PCM. It is demonstrated that if the device is isotropically downscaled by a factor of 1/k (k >1), the device operation energy (current) will be decreased by k 3 (k) times, and the device operation speed will be increased by k 2 times. The impacts of NW radius and length on PCM device performance are analyzed. Based on the analysis results, the suggestions to optimize the NW PCM device design are given.

Role of Inelastic Electron-Phonon Scattering in Ultra-Scaled Phase Change Material Nanostructures

“…The electron energy relaxation can be quantitatively calculated by using the quantity (6) which represents the energy carried by the electron when it is transported across the boundary between the k th principal layer and the k+1 th principal layer. It is computed that -(E 7 -E 1 )/E 1 < 4%, indicating that less than 4% of the energy carried by electrons is lost via inelastic scattering when they are transported from source to drain.…”

“…Phase change memory technology is promising to enable next-generation ultra-dense information storage devices [1][2][3][4][5][6][7][8][9][10][11]. One of the most attractive merits of the phase change material (PCM) based device technology is its superb scalability.…”

Multi-scale Analysis of the Crystallization of Amorphous Germanium Telluride

“…Phase change memory is promising to become the next-generation mainstream memory technology [1][2][3][4][5][6][7][8][9][10][11][12]. By reversibly switching the lattice of PCM between crystalline (c-) phase and amorphous (a-) phase, information can be stored in a nonvolatile manner.…”