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Lateral memristors configured with inert Pt contacts and mixed phase tin oxide layers have exhibited immediate, forming-free, low-power bidirectional resistance switching. Activity dependent conductance and relaxation in the low resistance state resembled short term potentiation in biological synapses. After scanning probe microscopy, x-ray photoelectron spectroscopy and electrical measurements, the device characteristics were attributed to Joule heating induced decomposition of the minority SnO phase and formation of a SnO2 conducting filament with higher effective n-type doping. Finally, the devices recognized input voltage pulse sequences and spectral data by returning unique conductance states, suggesting suitability for bio-inspired pattern recognition systems.

Carbon films deposited by filtered cathodic vacuum arc have been used to form high quality Schottky diodes on p-Si. Energetic deposition with an applied substrate bias of -1 kV and with a substrate temperature of 100 °C has produced carbon diodes with rectification ratios of ∼ 3 × 106, saturation currents of ∼0.02 nA and ideality factors close to unity (n = 1.05). Simulations were used to estimate the effective work function and the thickness of an interfacial mixed (C/SiO2) layer from the current/voltage characteristics of the diodes.

Energetically deposited graphitic carbon (C) is known to form high-endurance rectifying contacts to a variety of semiconductors. Graphitic contacts to n-type 6H-SiC have demonstrated current rectification ratios (at ± 1.5 V) up to 1:10 6. In this article, the current voltage temperature (I-V-T) characteristics of these devices are examined to reveal more detail on the junction/barrier properties that are critical to performance. Analysis of the I-V-T characteristics and disparity between barrier heights extracted from the I-V-T data and C-V data show inhomogeneity in the contacts and this has been quantified. Accounting for the inhomogeneity, the homogeneous Richardson constant of the n-type 6H-SiC can be extracted from the I-V-T data, and this value agrees with the reported theoretical value.

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