Dershin Gan

Characteristics and Mechanisms of Silicon-Oxide-Based Resistance Random Access Memory

Traditionally, a large number of silicon oxide materials are extensively used as various dielectrics for semiconductor industries. In general, silicon oxide cannot be used as resistance random access memory (RRAM) due to its insulating electrical properties. In this letter, we have successfully produced resistive switching and forming-free behaviors by zinc doped into silicon oxide. The current-voltage fitting data show that current transport mechanism is governed by Poole-Frenkel behavior in high-resistance state and Ohms law in low-resistance state, consisting with filament theory. Additionally, good endurance and retention reliabilities are exhibited in the zinc-doped silicon oxide RRAM.

Bipolar Resistive RAM Characteristics Induced by Nickel Incorporated Into Silicon Oxide Dielectrics for IC Applications

In this letter, we successfully produced resistive switching behaviors by nickel doped into silicon oxide at room temperature. The nickel element was doped into silicon oxide, which is a useful dielectric material in integrated circuit (IC) industries by cosputtering technology. Based on the proposed method, satisfactory reliability of the resistance switching device can be demonstrated by endurance and retention evaluation. We believe that the silicon oxide doped with nickel at room temperature is a promising method for resistive random access memory nonvolatile memory applications due to its compatibility with the IC processes.

Reducing operation current of Ni-doped silicon oxide resistance random access memory by supercritical CO2 fluid treatment

In the study, we reduced the operation current of resistance random access memory (RRAM) by supercritical CO2 (SCCO2) fluids treatment. The power consumption and joule heating degradation of RRAM device can be improved greatly by SCCO2 treatment. The defect of nickel-doped silicon oxide (Ni:SiOx) was passivated effectively by the supercritical fluid technology. The current conduction of high resistant state in post-treated Ni:SiOx film was transferred to Schottky emission from Frenkel-Pool due to the passivation effect. Additionally, we can demonstrate the passivation mechanism of SCCO2 for Ni:SiOx by material analyses of x-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.

Origin of Hopping Conduction in Sn-Doped Silicon Oxide RRAM With Supercritical

In this letter, we investigate the origin of hopping conduction in the low-resistance state (LRS) of a resistive random access memory device with supercritical CO2 fluid treatment. The dangling bonds of a tin-doped silicon oxide ( Sn:SiOx) thin film were cross linked by the hydration-dehydration reaction through supercritical fluid technology. The current conduction mechanism of the LRS in the posttreated Sn:SiOx thin film was transferred to hopping conduction from Ohmic conduction, owing to isolation of metal tin in the Sn:SiOx thin film by hydration-dehydration reaction. The phenomena can be verified by our proposed reaction model, which is speculated by the X-ray photoelectron spectroscopy analyses.

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Abstract Scanning transmission electron microscopy analyses of aluminized coatings on superalloy Rene 80 were used to characterize the microstructures, crystallographic relationships and qualitative compositions of various phases within the coatings. In the diffusion zone, elongated precipitates which extend from the β phase to the γ phase were identified to be σ phase and, in the outer region of the diffusion zone, M23C6 and σ grains were identified. The crystallographic relationships of γ, β and σ phases at the interface between the coating and the substrate were identified as 001] σ [111] γ, [110] σ [01 1 ] γ [001] σ [001] γ, [110] β [010] β [0 1 0] β [1 4 0] σ, (1 ° off) However, the β phase located away from the coating-substrate interface has no simple relationship with the σ phase and the M23C6. The results of an energy-dispersive X-ray analysis of various phases are also presented.

Fluid Treatment

In this letter, we introduced hydrogen ions into titanium metal doped into SiO2 thin film as the insulator of resistive random access memory (RRAM) by supercritical carbon dioxide (SCCO)2 fluid treatment. After treatment, low resistance state split in to two states, we find the insert RRAM, which means it has an operating polarity opposite from normal RRAM. The difference of the insert RRAM is owing to the resistive switching dominated by hydrogen ions, dissociated from OH bond, which was not by oxygen ions as usual. The current conduction mechanism of insert RRAM was hopping conduction due to the metal titanium reduction reaction through SCCO2.

Microstructures and crystallographic relationships in aluminized coatings on René 80

Abstract Electron and X-ray diffraction studies of aluminized coatings on Rene 80 indicate that the β phase has an L21 structure rather than a B2 structure in the diffusion zone. The L21-type superlattice is mainly due to the ordering of aluminum and titanium on the aluminium sublattice. However, in the outer zone the β phase is of a B2 structure. Anomalies including diffuse streaks, diffuse intensities or extra spots in the electron diffraction patterns of the β phase are observed in both the B2 and the L21 structure.

Hopping effect of hydrogen-doped silicon oxide insert RRAM by supercritical CO 2 fluid treatment

To improve the resistive switching properties of the resistive random access memory (RRAM), the supercritical carbon dioxide (SCCO₂) fluid is used as a low temperature treatment. In this letter, the Zn:SiO<i>x</i> thin films are treated by SCCO₂ fluid mixed with pure water. After SCCO₂ fluid treatment, the resistive switching qualities of the Zn:SiO_x thin films are carried out by XPS, fourier transform infrared spectroscopy, and IV measurement. We believe that the SCCO₂-treated Zn:SiO_x thin film is a proresistive switching properties mising material for RRAM applications due to its compatibility with portable flat panel display.

Superlattice of β-NiAl aluminized coatings on René 80

Incorporation of nitrogen as an oxygen-confining layer in the resistance switching reaction region is investigated to improve the reliability of resistance random access memory (RRAM). The switching mechanism can be attributed to the formation and rupture of conduction filaments. A compatible WSiON (around 5 nm) layer is introduced at the interface of tungsten silicon oxide (WSiOx) and TiN electrode to prevent the randomly diffusing oxygen ions surpassing the storage region of the WSiON layer. The double-layer WSiOx/WSiON memory structure would enhance the endurance over 100 times so as to better confirm the WSiOx RRAM application of nonvolatile memory.

Low Temperature Improvement Method on

Aging of Fe-30Mn-10Al-1C-1Si alloy at 550--700 C causes extensive precipitation of the [kappa] phase at austenite grain boundaries as well as within austenite grains, which will be named as intergranular and intragranular [kappa] phase respectively. The formation of fine intragranular [kappa] phase is considered to be a possible hardening mechanism for this alloy system. However, it has been shown that the presence of intragranular [kappa] phase can cause brittle fracture before yielding at subzero temperatures. On the other hand, the intergranular [kappa] phase alone can result in a severe loss in impact energy at both room and subzero temperatures. Owing to the importance of the precipitation of [kappa] phase on the mechanical properties, a better knowledge of the alloying effect on the precipitation is important for the further development of this alloy system. In the present work, a systematic study of the effect of alloying elements, aluminum and carbon in particular, on the precipitation of [kappa] phase was carried out over a range of composition within which a single phase austenite is formed upon solution treating and quenching.