Oxygen diffusion kinetics during SiO2/SiC plasma oxidation

Trade-off between Gradual Set and On/Off Ratio in HfOx-Based Analog Memory with a Thin SiOx Barrier 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.…”

“… 55 , 56 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, 41 , 47 it is higher in SiO x (2.03–4.6 eV) 44 − 48 compared to AlO x (1.26–3.6 eV) 40 , 41 and HfO x (0.7–1.5 eV). 27 , 42 , 43 A depth profile of the elemental composition obtained using XPS is shown in Figure 1 b–d for HfO x , HfO x /AlO x , and HfO x /SiO x , respectively.…”

“…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 .…”

Reliability and Stability Improvement of MOS Capacitors via Nitrogen–Hydrogen Mixed Plasma Pretreatment for SiC Surfaces

“…To understand better the SiO 2 /SiC interface chemical bonding, Si and C core-level spectra are examined in more details and are shown in Figure . The spectrum of Si 2p shown in Figure a can be resolved into three components, such as Si–O (103.3 eV), SiO x C y (102.2 eV), and Si–C (101.0 eV) bonds. , Compared with the sample of NH-0 min, the samples with NH plasma pretreatment have a lower peak intensity of SiO x C y , demonstrating that the SiO x C y defects are decreased. This is associated with the short O diffusion distance limiting the additional oxidation of SiC and the elimination of SiO x C y defects by N atoms.…”