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The effect of KrF excimer laser energy density (below and above the ablation threshold), number of shots and angle of laser incidence on the morphological reconstruction, structure and specular reflectance of Si[311] surfaces is reported. At low energy densities (0.1 to 0.3 J/cm2) laser irradiation results in a variety of nanostructures, depending on laser energy density and number of shots, such as nanopores (40-60 nm dia) and nanoparticles (40-80 nm dia). At energies greater than the laser ablation threshold (2 to 5 J/cm2) the formation of nanowires (200 nm dia, 6-8 microm length), and closely spaced silicon nanograins (100-150 nm dia) is observed. Experiments to study the effect of laser irradiation in the proximity of a fixed shape such as a linear step edge in the form of a stainless steel blade and a cylindrical cross-section Cu wire were also carried out. In both cases, linearly organized nanoparticles (150-200 nm diameter) and nanowires (60-80 nm diameter) formed close to the edge. There is a systematic degradation of long-range order with the number of shots and laser energy density as evidenced from X-ray diffraction studies. At an energy density of 2 J/cm2, and 100 shots the [311] oriented silicon surface made a transition to a randomly oriented nanocrystalline state.

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Cu x O-based resistive random access memory (RRAM) devices are fabricated with low, medium, and high oxygen affinity metals as the top electrode and gold and platinum as the bottom electrode. Switching performance of the device with varying oxygen affinity is observed. The variation, mean, and the cycle percentage of V set and V reset values decrease with the decrease in oxygen affinity but increase in the case of I reset . The reset power parameter decreases with oxygen affinity of metal electrodes (OAME). A generalized figure of merit (FM), which considers all the parameters (variation, mean, and cycles count) of a switching parameter (V set , V reset , I reset , and P reset ), is introduced to explain the performance. The FM also confirms the variation in switching parameters with oxygen affinity. This reveals that the performance of the device is improved with the decrease in oxygen affinity. The device fabricated with low oxygen affinity metal electrode, Ni, shows the best performance among all the Cu x O-based RRAM devices. Further improvement in device performance is achieved by changing the bottom electrode from Au to Pt with the top electrode being retained as a low oxygen affinity metal. This combination is shown to be the best in terms of retention and endurance.