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Resistive switching memory (RRAM) features many optimal properties for future memory applications that make RRAM a strong candidate for storage-class memory and embedded nonvolatile memory. This paper addresses the cycling-induced degradation of RRAM devices based on a HfO2 switching layer. We show that the cycling degradation results in the decrease of several RRAM parameters, such as the resistance of the low-resistance state, the set voltage V\mathrm{ set} , the reset voltage V\mathrm{ reset} , and others. The degradation with cycling is further attributed to enhanced ion mobility due to defect generation within the active filament area in the RRAM device. A distributed-energy model is developed to simulate the degradation kinetics and support our physical interpretation. This paper provides an efficient methodology to predict device degradation after any arbitrary number of cycles and allows for wear leveling in memory array. [ABSTRACT FROM AUTHOR]

Resistive-switching memory (RRAM) based on metal oxide is currently considered as a possible candidate for future nonvolatile storage and storage-class memory. To explore possible applications of RRAM, the switching variability and the cycling endurance are key issues that must be carefully understood. To this purpose, we studied the switching variability and the endurance in pulsed regime for HfOx-based RRAM. We found that the resistance window, the set/reset variability, and the endurance are all controlled by the maximum voltage Vstop , which is applied during the negative-reset operation. We demonstrate that the endurance failure is triggered by a negative-set event, where the resistance suddenly decreases during the reset. Cycling endurance is studied as a function of time, compliance current and Vstop , allowing to develop an Arrhenius-law model, which is capable of predicting device lifetime under various conditions. [ABSTRACT FROM PUBLISHER]

DNA nanostructures routinely self-assemble with sub-10 nm feature sizes. This capability has created industry interest in using DNA as a lithographic mask, yet with few exceptions, solution-based deposition of DNA nanostructures has remained primarily academic to date. En route to controlled adsorption of DNA patterns onto manufactured substrates, deposition and placement of DNA origami has been demonstrated on chemically functionalized silicon substrates. While compelling, chemical functionalization adds fabrication complexity that limits mask efficiency and hence industry adoption. As an alternative, we developed an ion implantation process that tailors the surface potential of silicon substrates to facilitate adsorption of DNA nanostructures without the need for chemical functionalization. Industry standard 300 mm silicon wafers were processed, and we showed controlled adsorption of DNA origami onto boron-implanted silicon patterns; selective to a surrounding silicon oxide matrix. The hydrophilic substrate achieves very high surface selectivity by exploiting pH-dependent protonation of silanol-groups on silicon dioxide (SiO2), across a range of solution pH values and magnesium chloride (MgCl2) buffer concentrations. [ABSTRACT FROM AUTHOR]