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A novel technique combination of ion bombardment (IB) and NH 3 plasma treatment (PT) has been presented to yield a highly effective charge storage layer for Si/SiO2/Si3N4/SiO2/Si (SONOS)-type nonvolatile memory applications. The IB technique creates additional trap sites within the charge storage layer strikingly to enhance the charge trapping/detrapping efficiency of the storage layer, and the NH 3 PT passivates shallow trap sites significantly to improve reliability characteristics. The distribution of trap sites corresponding with various energy levels is clearly described by discharge-based multipulse analysis. As compared with the control sample (without IB and NH 3 PT), the ionbombarded and NH 3 -plasma-passivated memory device has faster program/erase speeds and larger memory window. In addition, the competent reliability properties of the ion-bombarded and NH 3 -plasma-passivated memory, such as good endurance, long data retention, and acceptable disturbance, were also demonstrated in this letter.Index Terms-Discharge-based multipulse (DMP), Flash memory, ion bombardment (IB), metal/Al2O3/Si3N4/SiO2/Si (MANOS), NH 3 plasma treatment (PT).

The sol-gel derived technique has been proposed not only to tailor the microstructure of resistive layer but to control the amount of metal during device fabrication for resistive random access memory (ReRAM). Using the sol-gel derived technique can modulate the solution ratio to adjust the resistance and operation voltage. In addition, various metal concentrations can be doped in sol-gel derived resistive layer to significantly improve switching properties including switching speed and power consumption. Above all, forming energy and morphology of metal filament can be ordered by the sol-gel derived technique, which is desirable for practical ReRAM applications.

In this paper, a novel chemical soak method is proposed to fabricate a Cu-doped SiO 2 ReRAM device. This method can easily fabricate a lightly Cu-doped SiO 2 film and effectively improve the reliability of the conventional Cu-doped SiO 2 ReRAM device. A reproducible bipolar switching characteristic with set/reset voltage (ca. 2.5 V/ -0.7 V) is performed in this device and the electrical conduction in HRS and LRS are related to Poole-Frenkel and Ohmic conduction, respectively. Excellent performance in terms of high on/off ratio (~10 6 ), narrow range distribution of set and reset voltages, stable data retention, and up to 110 times switching cycles has been achieved by this novel chemical soak method for Cu-doped SiO 2 ReRAM device. IntroductionRecently, ReRAM (Resistive Random Access Memory) has been researched extensively as a promising candidate for the next-generation nonvolatile memory. Cu-doped SiO 2 as a resistive layer for ReRAM application has been reported to show the resistive switching behavior (1). The switching mechanism has also been proposed by the migration and accumulation of copper ions from copper electrode into the resistive layer (1-2). After several times of set/reset operations, the increment of copper ions concentration in resistive layer results in a hardly ruptured metallic filament under reset process. Thus, the concentration of copper ions in the resistive layer plays an important role in electrical properties, especially for reliability characteristics. In addition, there are many research for Cu-doped SiO 2 ReRAM device (1, 3-5), while the endurance characteristic is a lack of investigation.In this study, a novel chemical soak method is provided to fabricate a Cu-doped SiO 2 ReRAM device. Results showed that this novel chemical soak process is promising to fabricate a high performance Cu-doped SiO 2 ReRAM device. ExperimentalA new technique introduced copper into SiO 2 films by soaking the film in copper sulfate solution is successfully demonstrated in this paper. The chemical solution consists of ECS Transactions, 41 (3) 469-473 (2011) 10.1149/1.3633063 © The Electrochemical Society 469 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 131.215.174.8 Downloaded on 2015-06-27 to IPcopper sulfate pentahydrate and DI water. Thereamong, the molarity of copper sulfate pentahydrate is 0.4 M. The copper sulfate solution was stirred and heated to 65 o C on hot plate; meanwhile, the temperature of solution was monitored by thermograph. Samples were fabricated on prepared SiO 2 /Si-sub wafers. Firstly, a 200-nm thick TaN metal layer as the bottom electrode was deposited on the SiO 2 /Si-sub wafer by using sputtering. Then a 20-nm thick SiO 2 film was deposited by PECVD as the resistive layer for ReRAM devices. Subsequently, samples were soaked in the copper sulfate solution at 65 o C for 15 min and baked at 250 o C for 30 min in an oven for eliminating residual moisture. Finally, a 200-nm thick top TaN electrode was d...