Solid-state memory is ubiquitous in digital cameras, smart cell phones, tablet computers, and the latest laptop computers. As device size continues to shrink, the non-volatile memory becomes a limiting factor; consequently there is increasing demand for highly-scalable memory devices. This research focuses on an emerging and compact technology known as resistance random access memory (RRAM) that is based on resistance switching in metal oxide materials such as magnetite and bismuth oxide. The materials are deposited by electrodeposition, a simple and inexpensive processing method. In addition to opening up new possibilities for data-storage and retrieval, this research project has strong educational broader impacts. Students at the Materials Camp find producing materials for RRAM to be exciting because they have hand-held devices that depend on solid-state memory.
TECHNICAL DETAILS: The research focuses on the electrodeposition of metal oxide films and superlattices that exhibit resistance switching. A possible application of these materials is RRAM for solid-state memory. The materials in the study have multiple resistance states that can be accessed by simply varying the applied voltage, opening up new possibilities for multi-bit data storage and retrieval. Specific tasks are i) electrodeposition of superlattices in the magnetite/cobalt ferrite system, ii) using a focused ion beam to fabricate nanoscale contacts and cross-point architectures, iii) resistance switching in nanostructured polycrystalline films, iv) study of the mechanism of resistance switching in electrodeposited magnetite superlattices and films, and v) resistance switching in electrodeposited films of delta-Bi2O3. The project emphasizes correlating the nanostructure of the electrodeposited films with their resistance switching behavior.