Key concepts behind forming-free resistive switching incorporated with rectifying transport properties

Abstract

This work reports the effect of Ti diffusion on the bipolar resistive switching in Au/BiFeO3/Pt/Ti capacitor-like structures. Polycrystalline BiFeO3 thin films are deposited by pulsed laser deposition at different temperatures on Pt/Ti/SiO2/Si substrates. From the energy filtered transmission electron microscopy and Rutherford backscattering spectrometry it is observed that Ti diffusion occurs if the deposition temperature is above 600°C. The current-voltage (I–V) curves indicate that resistive switching can only be achieved in Au/BiFeO3/Pt/Ti capacitor-like structures where this Ti diffusion occurs. The effect of Ti diffusion is confirmed by the BiFeO3 thin films deposited on Pt/sapphire and Pt/Ti/sapphire substrates. The resistive switching needs no electroforming process, and is incorporated with rectifying properties which is potentially useful to suppress the sneak current in a crossbar architecture. Those specific features open a promising alternative concept for nonvolatile memory devices as well as for other memristive devices like synapses in neuromorphic circuits.

Lead-free epitaxial ferroelectric material integration on semiconducting (100) Nb-doped SrTiO3 for low-power non-volatile memory and efficient ultraviolet ray detection

“…The speed of ReRAM is about 10 ns, which is 100× faster than that of flash memory devices2. The development of ReRAM relies upon proper selection of materials including oxides, organics, solid electrolytes, and ferroelectrics34567891011. However, the resistive effects in solid electrolytes based ReRAMs are usually based on electroforming or chemical process, which is a destructive process as it involves chemical reaction that could lead to thermal damage of the devices11.…”

“…The development of ReRAM relies upon proper selection of materials including oxides, organics, solid electrolytes, and ferroelectrics34567891011. However, the resistive effects in solid electrolytes based ReRAMs are usually based on electroforming or chemical process, which is a destructive process as it involves chemical reaction that could lead to thermal damage of the devices11. On the other hand, ferroelectric materials have attracted enormous attention due to their remnant polarization and polarization inversion81112.…”

“…However, the resistive effects in solid electrolytes based ReRAMs are usually based on electroforming or chemical process, which is a destructive process as it involves chemical reaction that could lead to thermal damage of the devices11. On the other hand, ferroelectric materials have attracted enormous attention due to their remnant polarization and polarization inversion81112. No electroforming or chemical process takes place during the operation of ferroelectric ReRAM, thus enabling longer lifetime and faster operation.…”

“…No electroforming or chemical process takes place during the operation of ferroelectric ReRAM, thus enabling longer lifetime and faster operation. The data is stored, written or read by switching or inverting the polarization81112. Polarization represents the net dipole moment in the ferroelectric and the switching phenomenon is generally discussed in terms of domains which represent the local distribution of dipoles with alignment along the applied field direction1213.…”

“…Multiferroic BiFeO 3 (BFO) film has been grown on different substrates to investigate its switching behaviour for ferroelectric ReRAM applications7891011. BFO is attractive due to its simultaneous ferroelectric and antiferromagnetic characteristics exhibiting both high Curie temperature and Neel temperature15.…”