Novel Ion Bombardment Technique for Doping Limited Cu Source in SiOx-Based Nonvolatile Switching Layer

Abstract

A novel ion bombardment (IB) technique is presented to dope a limited Cu source in an SiOx switching layer (SiOx:Cu SL) for nonvolatile memory applications. Compared with other Cu-doping methods, this IB technique has many benefits, including a local-doping effect, room-temperature process, and compatibility with current IC manufacturing technology, besteading the 1T-1R integration. Through transmission electron microscopy and energy dispersive spectrometer analyses, an IB-induced SiOx:Cu SL is confirmed. In contrast with the conventional Cu/SiOx-stacked sample, this IB-induced SiOx:Cu SL exhibits superior performance in terms of lower forming/RESET voltages, higher uniformity of SET/RESET voltages, and more stable high-temperature retention characteristics. Additionally, so far, this IB-induced TaN/SiOx:Cu/TaN device has shown the best switching endurance properties for the general SiOx-based Cu filament resistance random access memory.