Phase‐change memory (PCM) has been developed for three‐dimensional (3D) data storage devices, posing huge challenges to the thermal stability and reliability of PCM. However, the low thermal stability of Ge2Sb2Te5 (GST) limits further application. Here, we demonstrate PCM based on In0.9Ge2Sb2Te5 (IGST) alloy, showing 180°C 10‐years data retention, 6 ns set speed, one order of magnitude longer life time, and 75% reduced power consumption compared to GST‐based device. The In can occupy the cationic positions and the In‐Te octahedrons with good phase‐change properties can geometrically match well with the host Ge‐Te and Sb‐Te octahedrons, acting as nucleation centers to boost the set speed and enhance the endurance of IGST device. Introducing stable matched phase‐change octahedrons can be a feasible way to achieve practical PCMs.

A new phase change material designed by three matched octahedrons has robust thermal stability and enhanced electrical properties and can be used for three‐dimensional phase change memory. (DOI: 10.1002/inf2.12233) image

A large crossbar array is desirable for high-density 3D stacking phase change memory (PCM) applications, in which the leakage current is mainly decided by selector devices. Meanwhile, a large driving current is also needed to meet the Reset operation of the PCM cell. Here, we propose a selector based on a nanoscale HfO2 film via As ion implantation, which has a low threshold voltage of 1.9 V, a milliamp-scale high driving current, a large selectivity of 106, fast turn on speed, and good endurance (108 switching cycles). These excellent performances make it applicable in the high-density stacked PCM application.