Filament Localization and Characterization in HfO2 ReRAM Cells using Laser Stimulation

Optical Beam Induced Resistance Change (OBIRCH) laser stimulation is used to detect the spatial location of filaments inside large area Resistive Random Access Memories (ReRAMs). This technique allows one to detect filaments at very low bias voltages, down to similar to 10 mV, significantly improving previous results obtained using near-infrared Photon Emission Microscopy (PEM). This capability is leveraged to detect, for the first time, the location of filaments before they are fully formed. Multi-filaments and logic state detection are also demonstrated.