Resistance switching in amorphous and crystalline binary oxides grown by electron beam evaporation and atomic layer deposition

Resistance switching random access non-volatile memories (ReRAM) could represent the leading alternative to floating gate technology for post 32 nm technology nodes. Among the currently investigated materials for ReRAM, transition metal binary oxides, such as NiO, CuxO, ZrOx, TiO2, MgO, and Nb2O5 are receiving increasing interest as they offer high potential scalability, low-energy switching, thermal stability, and easy integration in CMOS fabrication. In this work we investigate the resistive switching properties of NiO and Nb2O5 films grown by electron beam and atomic layer deposition (ALD) as a function of growth technique and electrode materials. The polycrystalline NiO and amorphous Nb2O5 films are initially in the high resistance state and exhibit reproducible unipolar switching after an appropriate forming stage. Beside noble metal electrodes, particular focus is on n+-Si, W, and TiN materials which are compatible with CMOS device fabrication process.