Effects of the compliance current on the resistive switching behavior of arsenic telluride thin films

Introduction 3D X-point array structure has attracted increasing attention for high-density resistive memory devices, but 3D X-point array structure with a purely linear resistive switching element suffers from sneak current... [ view full abstract ]

Introduction 

3D X-point array structure has attracted increasing attention for high-density resistive memory devices, but 3D X-point array structure with a purely linear resistive switching element suffers from sneak current paths. To suppress the leakage current, a two-terminal selection device, series connected with each resistive element in a one selector one resistive element (1S1R) memory cell configuration has been proposed. Recently, phase change random access memory (PRAM) has been intensively investigated for the application to cross-point array structure material because of their favorable features such as the low cost, non-volatility, simple structure etc. And selection devices which are based on chalcogenide material are interested as a 1S1R structure by intel-micron (2016). 

Method

In this study, Arsenic telluride binary chalcogenide compounds were used for memory switching and threshold switching material. Arsenic telluride amorphous thin films were deposited by RF magnetron co-sputter using As₂Te target and Te target. The thicknesses of the Arsenic telluride thin films were 40 nm for all compositions, which was confirmed by Transmittance electron microscopy (TEM). Crystallinity of Arsenic telluride thin films as a function of annealing temperature and Te compositions was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Crystallization temperature was analyzed by Differential scanning calorimeter (DSC) and analysis of the chemical bonding states with varying post annealing temperature of As-Te thin films by Raman spectroscopy. 

Result

OTS behavior with As_xTe_1-x film thickness, device area and annealing temperatures were investigated. OTS behavior with As_xTe_1-x film thickness, device area and annealing temperatures were investigated. We observed two types of changeable resistance switching effects in a arsenic telluride film, memory type resistive switching at high compliance current and threshold switching type at low compliance current.

Discussion

The result shows that memory and threshold switching is occurred by control of compliance current, films of thermal stability and concentration of Te composition in Arsenic telluride binary thin film devices.