NQS

About: NQS is a research topic. Over the lifetime, 337 publications have been published within this topic receiving 4226 citations.

Non-quasi-static effects in advanced high-speed bipolar circuits

Abstract: A detailed study on the non-quasi-state (NQS) effects in advanced high-speed bipolar circuits is presented. An NQS Gummel-Poon-compatible lumped circuit model, which accounts for carrier propagation delays across various quasi-neutral regions in bipolar devices, is implemented in the ASTAP circuit simulator. The effects are then evaluated and compared with those for the conventional Gummel-Poon model for the emitter-coupled logic (ECL) circuit, the non-threshold-logic (NTL) circuit, and various advanced circuits utilizing active-pull-down schemes. For the ECL circuit, the effect decreases with reduced power level and increased loading. For the NTL circuit, due to its front-end configuration, the effect is more significant than that for the ECL circuit but tends to increase with reduced power level. As the passive resistors (and the associated parasitic RC effect) are decoupled from the delay path and the circuit delay is made more intimately related to the intrinsic speed of the devices in various advanced active-pull-down circuits, the delay degradation due to NQS effect becomes more significant. >

Passive device for the detection and/or determination in situ of amines in gases

Abstract: A sensor for the detection and/or determination in situ of amines in air, such as atmospheric air, is obtained by means of a direct, easy and reproducible synthesis consisting in soaking the derivatisation agent sodium 1,2-naphthoquinone-4-sulfonate (NQS) in polydimethylsiloxane (PDMS). It has been shown that the device can detect amine concentrations of 3 mg/m 3 in 5 hours. Both the device and its response to the presence of amines remain stable over time. In addition, no external source is required for detection (i.e. it is a passive sensor that allows amines to be detected by means of visual inspection), requiring zero energy cost and having no toxicity, since both the NQS and the PDMS are non toxic.

Modeling of anomalous frequency and bias dependences of effective gate resistance in RF CMOS

Abstract: This paper explains the frequency and bias dependences of the effective gate resistance (real part of h11) by considering the effect of the gate-to-body capacitance, gate-to-source/drain overlap capacitances, fringing capacitances, and nonquasi-static (NQS) effect. A new method of separating the physical gate resistance and the NQS channel resistance is proposed. Separating the gate-to-source parasitic capacitances from the gate-to-source inversion capacitance is found to be necessary for an accurate modeling of all the Y-parameters

Halo Doping: Physical Effects and Compact Modeling

Abstract: In this paper, we present the physical effects observed when halo implants are used to control short channel effects (SCE). The impact of using halo implants was studied using a 2 or 3 segmented transistor. The multi-segmented transistor model approach show that (1) the mobility needed to match IV data shows an artificial length dependence, (2) the threshold voltage needed to match the IV data is different from the threshold voltage needed to match CV data and (3) the NQS effects are more severe for halo transistors. Two dimensional numerical devices simulations were also performed to comprehend the observed output resistance degradation. Based on these numerical simulations a 2-transistor model is proposed to describe output resistance in compact models.