Chemical routes to magnetic nonvolatile memory devices

Magnetoresistive (or magnetic) random-access memories (MRAMs) belong to the nonvolatile memory devices, using magnetism to store information for long time periods. MRAMs are faster than mechanical hard disk drives and unlike solid-state drives (SSDs), can store data even without regular energy supply. A few other ideas, such as ferroelectric and phase-change materials, are also expected to show similar properties but are scarcely investigated. Technologically, MRAMs are often produced by sputtering, atomic layer deposition, or similar thin-film technologies. Chemical methods, however, are also involved, such as deposition of thin films by chemical solution routes, wet etching to produce patterned structures, and chemical polishing to create the desired surface roughness. Here, we give an overview of possible chemical techniques applicable to the production of magnetic nonvolatile memory devices, offering possibilities to use new materials and process them differently from the pure physical route.