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Black Phosphorus Transistors
Published in Yongqing Cai, Gang Zhang, Yong-Wei Zhang, Phosphorene, 2019
The field-effect transistor (FET), as a typical voltage-controlled current source, is a transistor that uses an electric field to control the electrical conductivity of a channel consisting of semiconductor material. Generally, a FET contains three terminals: the source (S), through which the carriers enter the channel; the drain (D), through which the carriers leave the channel; and the gate (G), which modulates the channel conductivity. When a FET works in a common-source mode in which S is connected to the ground, voltages Vds and Vgs are applied respectively to D and G. Therefore, there are two kinds of characteristic curves for FETs according to the measuring conditions. One is transfer characteristic (Vgs–Ids), in which the source–drain current Ids is obtained by sweeping the gate voltage (Vgs) with a fixed drain voltage (Vds). The other is output characteristic (Vds–Ids), in which Ids is measured by sweeping Vds under a fixed Vgs.
Power Electronics
Published in Mohd Hasan Ali, Wind Energy Systems, 2017
Most DC-to-DC converters also regulate the output voltage. Some exceptions include high-efficiency light-emitting diode (LED) power sources, which are a kind of DC-to-DC converter that regulates the current through the LEDs, and simple charge pumps, which double or triple the input voltage. Electronic switch-mode DC-to-DC converters convert one DC voltage level to another by storing the input energy temporarily and then releasing that energy to the output at a different voltage. The storage may be in either magnetic field storage components (inductors, transformers) or electric field storage components (capacitors). This conversion method is more power efficient (often 75 to 98%) than linear voltage regulation (which dissipates unwanted power as heat). This efficiency is beneficial to increasing the running time of battery-operated devices. The efficiency has increased since the late 1980s due to the use of power field-effect transistors (FETs), which are able to switch at high frequency more efficiently than power bipolar transistors, which incur more switching losses and require a more complicated drive circuit. Another important innovation in DC-to-DC converters is the use of synchronous rectification replacing the flywheel diode with a power FET with low “on” resistance, thereby reducing switching losses.
Basic electronics
Published in Raymond F. Gardner, Introduction to Plant Automation and Controls, 2020
The two types of FETs are the Junction Field-Effect Transistor (JFET) and Metallic-Oxide Semi-Conductor Field-Effect Transistor (MOSFET). The big difference is that the JFET operates in the depletion mode by controlling the flow of holes, and the MOSFET operates in the enhancement mode by controlling the flow of electrons. The JFETs’ P-N junction provides high input impedance, while MOSFETs use an isolated gate, which results in lower gate-leakage current and better control. The JFET gate must never be forward biased, while reversing polarity on the MOSFET has no deleterious effects.
Analysis of heat conduction in a nanoscale metal oxide semiconductor field effect transistor using lattice Boltzmann method
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Oussama Zobiri, Abdelmalek Atia, Müslüm Arıcı
The necessity of faster data processing, such as data transmission and data storage has been realized in recent years. During the data transmission by electrons to electronics, circuits may lead to unwanted hotspots (Chen 2005). The most commonly used materials in electronic industries are semiconductor materials. Among them, silicon (Si) is the dominating semiconductor material utilized for microelectronics devices (Nasri et al. 2015b). The Field-Effect Transistor (FET) is the essential component of semiconductor. The most popular type of isolated gate FET used in a variety of microelectronic is the Metal Oxide Semiconductor Field-Effect Transistor (MOSFET). Hundreds of millions of semiconductors are assembled on a few square centimeters chip area (Pop, Sinha, and Goodson 2006). The channel region in the MOSFET was projected to be 13 nm in 2018, however, the miniaturization of MOSFET has already reached the nano-scale, and it is expected to be less than 6 nm in 2026 (Fiori et al. 2014).
A novel SOI MESFET to spread the potential contours towards the drain
Published in International Journal of Electronics, 2020
Mohaddeseh Mohtaram, Ali Asghar Orouji
Unlike Bipolar transistors (BJTs), Field Effect Transistors (FETs) are unipolar devices. It means, there is only one type of carrier, electron or hole, participate in the current of the channel, which makes it possible to exhibit high frequency and low noise behaviour. Among field effect transistors, Metal Semiconductor FETs (MESFET) have large applications in amplifiers, mixers, and oscillators. These devices are a voltage controlled component. In fact, a variable electric field controls the current of the source to the drain with changing the voltage applied to the gate. So far, various efforts have been made to improve the frequency and DC characteristics of MESFET transistors (Braga & Hiu Yung Wong, 2017; Dutta, 2016; Jia et al., 2015; Jia, Hu, & Zhu, 2018; Jia, Yang, & Zhang, 2013; Jia, Zhang, Xing, Luo, & Duan, 2015; Jia, Zhang, Xing, & Ma, 2015; Lakhdar & Lakehal, 2017; Mohtaram & Orouji, 2018)
Self-assembled molecular devices: a minireview
Published in Instrumentation Science & Technology, 2020
An active device that changes the width of the conductive channel to control the carrier motion by externally applied voltage to produce an electric field is called a field effect transistor (FET). In order to maintain the normal point leveling of electrical signals in the circuit, it has both switching and gain functions. The key FET parameters are the field effect mobility and switch ratio.