In-situ microstructure observation of oxidized SiC layer in surrogate TRISO fuel particles under krypton ion irradiation

Trade-off between Gradual Set and On/Off Ratio in HfOx-Based Analog Memory with a Thin SiOxBarrier Layer

“…The titanium capping layer is known to improve device characteristics such as nonvolatility at high temperature (85 °C), uniformity in switching and low forming voltage. , During the forming operation, oxygen vacancy-rich conductive filaments are formed within the active layer oxides. While there is a range in general for the activation energy of oxygen vacancy diffusion, , it is higher in SiO x (2.03–4.6 eV) − compared to AlO x (1.26–3.6 eV) , and HfO x (0.7–1.5 eV). ,, A depth profile of the elemental composition obtained using XPS is shown in Figure b–d for HfO x , HfO x /AlO x , and HfO x /SiO x , respectively. The XPS depth profiles show that the resulting interfaces of the device structures have SiO x and AlO x barrier layers at the bottom electrode interface.…”

“…The elemental distribution is characterized using X-ray photoelectron spectroscopy (XPS) depth profiling. The barrier layer is added to the oxide/BE electrode interface, where the CF breaks during reset. − Compared to AlO x (1.26–3.6 eV) , and HfO x (0.7–1.5 eV), ,, the SiO x barrier layer exhibits a high activation energy for oxygen vacancy diffusion, ranging from 2.03–4.6 eV. − This makes it a more formidable oxygen vacancy migration barrier than both AlO x and HfO x . This is expected to enable controlled resistance change during the set due to the slower motion of V o .…”