Figure 1. The speed of resistance switching in ReRAM devices depends on the migration of oxygen ions in Ta2O5 and other amorphous transition metal oxides to form atomically thin conductive filaments (low resistance state - ON) and rupture them (high resistance state - OFF) .
Figure 2. The evolution of mean square displacement of atoms in amorphous Ta2O5 over 10 ns long MD simulations .
Figure 3. Arrhenius plot to determine activation energies Ea for amorphous Ta2O5 .
Figure 4. MD simulations show how Co filament in the Co/HfO2/Pt device forms a conductive bridge across the HfO2 dielectric when an electric field is applied across the device .
Figure 5. DFT-NEGF simulation of transmission for the configuration in Figure 4, confirming that there is a conductive bridge formed when electric field is switched on .
Figure 6. DFT-NEGF simulations show that Al mono-atomic bridges have the highest transmission near the Fermi level, as compared to Au and Cu .
Figure 7. Increasing DOS around Fermi level as the Au replacement percentage of S gets larger results in the transition from the HRS to the LRS state in the MoS2-based atomristor .
Figure 8. Nb:SrTiO3/SrTiO3/Pt model resistive switching system studied with the DFT-NEGF methodology in QuantumATK .
Figure 9. Current-voltage characteristics at different temperatures for the Nb:SrTiO3/SrTiO3/Pt model resistive switching system .
Figure 10. Investigation how various metal dopants aﬀect oxygen vacancy formation in crystalline and amorphous Ta2O5. Study suggests that p-type dopants (Al, Hf, Zr, and Ti) can lower the formation energy and thus the forming/set voltage and improve retention properties of ReRAM based on Ta2O5 .