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Solution-Processed Oxide-Semiconductor Films and Devices
Published in Sam Zhang, Jyh-Ming Ting, Wan-Yu Wu, Functional Thin Films Technology, 2021
Bui Nguyen Quoc Trinh, Endah Kinarya Palupi, Akihiko Fujiwara
Solar cells are semiconductor devices which convert electromagnetic wave (light) energy directly into electricity by the photovoltaic effect. The first solid-state photovoltaic cell was discovered by C. E. Fritts in 1883 [6, 7]. The device was made of a layer of selenium overlaid with a thin film of gold (Figure 9.2(a)) [8], which is now regarded as Schottky barrier junction type photodiode. The photovoltaic effect at the p-n junction, consisting of p- and n-type semiconductors (Figure 9.2(b)), was first observed by R. S. Ohl [9]. The efficiency of these solar cells was as low as around 1%, which was not enough for the application. First practical solar cell with an efficiency of about 6% was demonstrated using a single-crystal sample by C. S. Fuller, D. Chapin and G. Pearson in 1954. Following wafer-based solar cells with crystalline materials (first-generation solar cells), thin-film solar cells (second-generation solar cells) are developed. For these types of devices, a wide variety of materials, such as amorphous silicon (a-Si), cadmium telluride (CdTe), copper indium gallium selenide (CIGS) etc., can be used. The efficiency of the first- and second-generation solar cells has been improved and is now more than 20%. For higher efficiency, multi-junction solar cells (third-generation solar cells), consisting of a number of p-n junctions (Figure 9.2(c)), have been investigated, and the cell efficiency is close to 50%.
Semiconductor Physics and Devices
Published in Manoj Kumar Majumder, Vijay Rao Kumbhare, Aditya Japa, Brajesh Kumar Kaushik, Introduction to Microelectronics to Nanoelectronics, 2020
Manoj Kumar Majumder, Vijay Rao Kumbhare, Aditya Japa, Brajesh Kumar Kaushik
A diode is a semiconductor device that allows the flow of current only in one direction. It consists of two electrodes called cathode (negative terminal) and anode (positive terminal), as shown in Figure 1.6. When voltage polarity on the anode side is positive as compared to that on the cathode side, the diode conducts and is considered a low-value resistor. If voltage polarity at the anode side is more negative as compared to that on the cathode side, the diode is said to be in reverse-biased mode and it does not conduct. There are many types of diodes of which PN diode and Zener diode are the most important due to their applications. Here, we will explicitly explain about the PN diode.
Graphene-Based Single-Electron Transistors
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
A transistor is a three-terminal semiconductor device that can amplify a signal and act as a switch or “gate.” In this structure a source and drain contact are connected by a gate-dependent conductor; this results in a gate controllable current through the source–drain contact. Invented in 1948 primarily as a substitute for the vacuum tube, its true potential regarding reliability, miniaturization, and switching speed soon became evident, and today, the transistor is regarded as the most important invention of the 20th century. As the transistor size continues to reduced to pack more computing power on a chip and reduce the price per resistor, quantum mechanical effects became appreciable and with it the SET emerged. SETs are based on a quantum dot-like structure and can theoretically be downscaled to the atomic level.
Intelligent Short-Circuit Protection with Solid-State Circuit Breakers for Low-Voltage DC Microgrids
Published in IETE Journal of Research, 2023
Prateem Pan, Rajib Kumar Mandal
The various semiconductor devices available for SSCBs are briefly described in this section. The protection criteria for SSCBs in the has increased, given the availability of semiconductor devices of operating at switching frequencies below during the FCL applications, and capable of blocking high short-circuit currents within microseconds . The usually used semiconductor devices are: insulated gate bipolar transistors (IGBTs), silicon-controlled rectifiers, gate turn-off thyristors (GTOs), and integrated gate-commutated thyristors (IGCTs). Wide bandgap devices (mostly silicon carbide or gallium nitride) are the most recent additions to SSCB applications. A thyristor is a semi-controlled device that is mostly employed in AC circuit breakers since a natural trip requires a zero-crossing current [23]. To immediately disconnect from non-zero current, an auxiliary circuit is necessary. When compared to commercial IGBTs of similar rating, the RB-IGCT has a smaller operating voltage drop among the control units. For example, a ABB-IGBT (5SNA1500E250300) has a working voltage drop [45]. A operational voltage loss is visible in a similar RB-IGCT, i.e. the voltage drop is about half that of an IGBT. Considering the characteristics of thyristor high turn-off current capacity, and low conduction losses, ABB chose RB-IGCT as a solid-state switch for SSCB [46]. RB-IGCT can only conduct current in one direction and blocks both forward and reverse voltages.
A review of hybrid renewable energies optimisation: design, methodologies, and criteria
Published in International Journal of Sustainable Energy, 2023
Olalekan Kunle Ajiboye, Chimere Victor Ochiegbu, Eric Antwi Ofosu, Samuel Gyamfi
Photovoltaic (PV) cells are P-N junction semiconductor devices that convert sunlight (photons) to electricity (Bhandari et al. 2014). Its equivalent circuits are made up of a current source (photocurrent), one or two diode(s) parallel to the current source, an internal resistor to impede the flow of current, and a shunt resistor to express current leakages (Baba Kyari and Ya’u Muhammad 2019). PV models are classified as single-diode or double-diode models while the most commonly used model in history is single-diode (Rao 2009).
An Efficient Technique for Power Management in Hybrid Solar PV and Fuel Cell System
Published in Smart Science, 2018
Krishan Kumar, M.A. Ansari, Shreshth Kumar Varshney, Vinay Rana, Arjun Tyagi
The basic unit of a solar PV array is a solar cell. It is a semiconductor device that converts sunlight into electricity directly by the photovoltaic effect. A large number of solar cells connected in series form a solar PV module and a solar PV array is a combination of series or parallels connected PV modules. An equivalent electrical circuit of the solar cell is shown in Figure 2 [15]: