Affiliation:
1. National Institute of Advanced Industrial Science and Technology (AIST) Research Center for Emerging Computing Technologies (RCECT) Tsukuba Ibaraki 305–8568 Japan
Abstract
AbstractThe spin Hall effect enables fast and reliable writing operations for next‐generation spin‐orbit‐torque magnetoresistive random‐access memories (SOT‐MRAMs). To develop SOT‐MRAMs; however, the spin Hall material should have a sufficiently low writing energy and high annealing stability for the semiconductor integration process. Thus far, none of the crystalline‐based spin Hall materials are able to satisfy these requirements. Here, a promising solution for SOT‐MRAMs is provided using amorphous W─Ta─B alloys. Even without a long‐range crystal order, W─Ta─B alloys exhibit both large effective spin Hall angles up to 40% derived from a Ta substitutional doping and superior annealing stability (up to 400 °C) due to the addition of B, enabling them to satisfy both requirements. Nanoscale three‐terminal SOT‐MRAM cells are fabricated, and these are demonstrated to have high magnetoresistance ratios (up to 130%) and extremely low intrinsic switching current densities (down to 4 × 106 A cm−2). These results show that amorphous spin Hall materials can provide the key for realizing high‐performance SOT‐MRAMs.
Subject
Electronic, Optical and Magnetic Materials