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As monolithic integration of the microwave circuits progresses, the microstrip line used as a fundamental transmission medium becomes extremely small in size. As the transmission line is miniaturized, it becomes necessary to consider the effect of the shape of the edges of the strip conductor in addition to the thickness. in this paper, an integral equation is derived for the charge density distribution on the strip conductor surface as the unknown. The transmission line characteristics are obtained by discretizing the integration range. Further, the effect of the trapezoidal cross section of the strip conductor formed by etching and plating on the characteristic parameters is specifically studied. [ABSTRACT FROM AUTHOR]

Learning by human beings is achieved by changing the synaptic weights of a neural network in the brain. Low frequency stimulation temporarily increases a synaptic weight, which then decreases to the initial low state in the interval after each stimulation. Conversely, high frequency stimulation keeps a synaptic weight at an elevated level, even after the stimulation ends. These phenomena are termed short‐term plasticity (STP) and long‐term potentiation (LTP), respectively. These functions have been emulated by various nonvolatile devices, with the aim of developing hardware‐based artificial intelligent (AI) systems. In order to use the functions in actual AI systems with other conventional devices, control of the operating characteristics, such as matching a decay constant in STP, is indispensable. This paper reports an electrochemical method for controlling the characteristics of time‐dependent neuromorphic operations of molecular gap atomic switches. Pre‐doping of Ag+ cations into an ionic transfer layer (Ta2O5) changes the amount of shift in an electrochemical potential in the time‐dependent operation, which drastically improves the decaying characteristics in STP mode. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 29-year-old pregnant woman at 29 weeks of gestation was taken to the hospital due to rupture of the amniotic membrane. It mentions that ethylenediaminetetra-acetic acid (EDTA) showed a haemoglobin concentration, and states the diagnosis of grey platelet syndrome (GPS) by a haemorrhagic tendency. It also mentions that pseudo-GPS appeared to be induced by EDTAdependent platelet degranulation.

Cu and Ag redox reactions at the interfaces with Ta2O5 and the impact of Ta2O5 film density on the forming process of Cu,Ag/Ta2O5/Pt atomic switch structures are investigated. Cyclic voltammetry measurements revealed that under positive bias to the Cu (Ag) electrode, Cu is preferentially oxidized to Cu2+, while Ag is oxidized to Ag+ ions. Subsequent negative bias causes a reduction of oxidized Cu (Ag) ions at the interfaces. The diffusion coefficient of the Cu and Ag ions in the Ta2O5 film is estimated from the results from different bias voltage sweep rates. It is also found that the redox current is enhanced and the forming voltage of the Cu/Ta2O5/Pt cell is reduced when the density of the Ta2O5 film is decreased. This result indicates the importance of the structural properties of the matrix oxide film in understanding and controlling resistive switching behavior. [ABSTRACT FROM AUTHOR]

ReRAMs using oxygen vacancy drift in their resistive switching are promising candidates as next generation memory devices. One remaining issue is degradation of the on/off ratio down to 102 or less with an increased number of switching cycles. Such degradation is caused by a local hard breakdown in a set process due to a very high electric field formed just before the completion of a conductive filament formation. We found that introducing an ultra-thin SiO2 layer prevents the hard breakdown by dynamical moderation of the electric field formed in the TaO x matrix, resulting in repeated switching while retaining a higher on/off ratio of about 105. (© 2015 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

We propose a three-terminal nanometer metal switch that utilizes a solid electrolyte where a nanoscale metal filament is stretched and retracted. Its operating principle is based on electrochemical reaction and ion migration in the electrolyte. The fabricated device is composed of a solid electrolyte layer (CuS), a gate (Cu), a source (Cu), and a drain (Pt). After the Cu filament is formed between the source and the drain by applying the drain voltage, repeatable on/off switching in the drain current is obtained by controlling the gate voltage. The on/off current ratio can be as high as 10, and the programmable cycle is around 50. Each state can be kept for up to 40 days. Since the gate is separated from the current path, the switching current can be reduced to 10 μA, which is two orders of magnitude smaller than that of a two-terminal switch. In this paper, we present the operating principle and electrical characteristics of the three-terminal switches, and discuss how suitable they are for reconfigurable circuits. © 2011 Wiley Periodicals, Inc. Electron Comm Jpn, 94(4): 55-61, 2011; Published online in Wiley Online Library (). DOI 10.1002/ecj.10214 [ABSTRACT FROM AUTHOR]

We have investigated solid electrolyte switches that utilize electrochemical reactions (deposition and dissolution) of metallic ions. The switch turns off or on when a metallic bridge electrochemically forms or dissolves in the solid electrolyte. Each state is nonvolatile and the switching is repeatable up to 105 cycles. The promising application is a programmable switch in a field programmable logic because of its small size (<30 nm) and low ON resistance (<100Ω). This paper discusses the electrical characteristics, operation principle, and applications of the solid electrolyte switch. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(1): 68–73, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20542 [ABSTRACT FROM AUTHOR]