1,721,104 research outputs found
Engineering the Maxwell-Wagner polarization effect
No full textLayered structures, when supporting the Maxwell–Wagner polarization mechanism, exhibit very large effective electric permittivity and thus can be used for miniaturizing purposes. However, the large interfacial dimensions evolved, limit the Maxwell–Wagner polarization at relatively low frequencies. Any element or mechanism that causes a spatial variation of charge density, contributes to the dielectric susceptibility of a medium. Thus, intentionally planted polarization states can be used for further exploiting the Maxwell–Wagner polarization mechanism
Surface texturing for Maxwell-Wagner polarisation engineering
No full textSurface texturing techniques that are applied in laminar structures to extend the supported Maxwell–Wagner polarisation are described. The roughness of the semiconductor surface is increased, resulting in a subdivision of the large Si–SiO2 interfaces to a multitude of small interfaces. Measured results demonstrate that this surface texturing has a direct effect on the relaxation of the Maxwell–Wagner polarisation and, in particular, at the interfacial to atomic polarisation transition
Distributed filter design on silicon CMOS
No full textWe report an investigation on the feasibility of developing distributed circuit elements and filters using standard complementary metal-oxide-silicon (CMOS) technologies. We propose to exploit the low loss interfacial polarisation propagating modes known to occur on multilayered substrates to realise a high effective substrate dielectric constant. Our approach allows the realisation of physically small but electrically large distributed circuit elements and filters on a standard CMOS substrate without recourse to high K material
Cost-effective fabrication of nanoscale electrode memristors with reproducible electrical response
Full text linkThis Letter aims to promote basic research into memristors, which will help provide theorists with much-needed reliable benchmarks and will also aid the technology progress. It addresses an information gap presently in the literature on simple microfabrication techniques for the realisation of such devices. Consequently, a fabrication method is reported for implementing the full active-material stack, requiring a single lithography and evaporation step. A cost-effective technique that can reliably shrink device lateral dimensions towards the nanoscale is also demonstrated. Experimental results confirm the suitability of the proposed methods for fabricating memristors of varying dimensions that exhibit consistent electrical characteristics.Accepted versio
Easily integrable Metal-Insulator-Metal (MIM) selector devices for high density ReRAM crossbar arrays
No full textHigh precision analogue memristor state tuning
No full textA report is presented on the operation of an analogue programming circuit for accurately setting the state of a memristor. The circuit exploits the dynamic modulation of resistance under a constant DC bias while real-time measurements of the memristance are performed using an AC signal. The circuit employs feedback for converging the state of a device at any required level within a decade. This allows the memristor to act as an analogue potentiometer, with its resistance corresponding to an input analogue voltage. This implementation was tested with the HP memristor model revealing an accuracy of less than 0.4% (8 bit precision) in relation to the full dynamic range
Application of Maxwell-Wagner polarization in delay lines
No full textThe propagation characteristics of metal–insulator–semiconductor (MIS) lines are controlled by the resistivity of the substrate, the operating frequency and the ratio of the semiconductor to insulator layer thicknesses. A strong interfacial polarisation, also known as the Maxwell–Wagner polarisation, is often responsible for the significant slow-down of the propagation velocity of MIS microstrip transmission lines. This phenomenon has been applied in the development of miniature delay lines exhibiting large electrical dimensions. In this paper we review most previously presented designs and we examine the effect of this polarization mechanism under various parameters. Finally, the presented micro-scale delay lines, exhibit comparable slowing factors with our predecessors at the cost of lower attenuation
Computing motion with 3D memristive grid
No full textComputing the relative motion of objects is an important navigation task that we routinely perform by relying on inherently unreliable biological cells in the retina. The non-linear and adaptive response of memristive devices make them excellent building blocks for realizing complex synaptic-like architectures that are common in the human retina. Here, we introduce a novel memristive thresholding scheme that facilitates the detection of moving edges. In addition, a double-layered 3-D memristive network is employed for modeling the motion computations that take place in both the Outer Plexiform Layer (OPL) and Inner Plexiform Layer (IPL) that enables the detection of on-center and off-center transient responses. Applying the transient detection results, it is shown that it is possible to generate an estimation of the speed and direction a moving object
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