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The electrical characteristics of a double-gate field-effect transistor (DGFET) based on the MA2N4 family of 2-D monolayers as channel materials are studied. The materials’ key electronic parameters, including effective mass, bandgap, and work function are investigated using density functional theory. Assessment of band structures suggests that MSi2N4 and TiGe2N4 are indirect semiconductors, whereas other compounds demonstrate direct bandgap. The projected density of state is obtained to explore the contribution of M and Z elements to both conduction and valence bands. The quantum transport characteristics of the double gate FET with MA2N4 monolayers have been studied using non-equilibrium Green function (NEGF) formalism. The current–voltage characteristics are obtained, and several essential device parameters of the FET including ON-current, OFF-current, ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio, and sub-threshold swing (SS) are extracted. Few monolayers of this family demonstrated better short channel device characteristics when used as channel materials, including ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio $\ge 10^{{8}}$ and a SS of about 60 mV/dec for the channel length down to 5 nm.

This article presents a small-signal model of intrinsic gallium nitride high electron mobility transistor (GaN HEMT) for non-quasi-static analysis. The model is derived from the charge-based approach presented in the EPFL HEMT analytical model. The results are obtained in the form of trans-admittance parameters for a two-port network. The model takes into account the current continuity equation in the frequency domain and ignores short-channel effects. The results have been compared in a wide frequency range with technology computer-aided design (TCAD) simulation and show perfect agreement in all operating regions from linear to pinch-off.

Automotive engines spend a considerable portion of their life in idle state, where their characteristics are highly nonlinear and time varying. Efficient control of the engine in idle state significantly improves fuel economy, emission level and drivability. In this work, we proposed a combined fuzzy-PID idle speed controller which improves stability, fuel consumption and emission level, during normal operation as well as transient loads. In order to study the performance of control algorithm, XU7-1761cc gasoline port fuel injection engine has been modeled in idle state. This model calculates engine speed as a function of idle air valve position and ignition angle. This model demonstrated maximum of 8% error during parallel model in the loop and engine in the loop operation. After tuning the membership functions, performance of fuzzy-PID controller has been compared with baseline PID controller of engine control unit. Model in the loop simulation demonstrated that fuzzy-PID controller is more accurate than baseline PID controller, unconditionally stable and is able to reduce fuel consumption in the order of 14% compared to baseline controller. Finally, an experimental setup for real-time control of idle air valve based on proposed controller has also been developed.