|
Wide-bandgap semiconductors are semiconductor materials that permit devices to operate at much higher voltages, frequencies and temperature than conventional semiconductor materials allowing more powerful electrical mechanisms to be built which are cheaper and more energy efficient. "Wide-bandgap" refers to higher voltage electronic band gaps significantly larger than one electronvolt (eV). The exact threshold of "wideness" often depends on the context, but for common usage, "wide" bandgap typically refers to material with a band gaps of at least three eV, significantly greater than that of the commonly used semiconductors, silicon (1.1 eV) or gallium arsenide (1.4 eV). WBG semiconductors are considered by the US Department of Energy to be a foundational technology that will transform multiple markets and industries, resulting in billions of dollars of savings for businesses and consumers when use becomes widespread. Applications include optoelectronic devices such as those for high voltage LED lighting and power components needed for higher efficiency transformers for grid and alternative energy generation as well as the robust and efficient power components used in high energy vehicles from electric trains to plug-in electric vehicles. Wide bandgap materials are often utilized in applications in which high-temperature operation is important. ==Use in devices== Wide bandgap materials have several characteristics that make them useful compared to lower bandgap materials. The higher energy gap gives devices the ability to operate at higher temperatures, and for some applications, allows devices to switch larger voltages. The wide bandgap also brings the electronic transition energy into the range of the energy of visible light, and hence light-emitting devices such as light-emitting diodes (LEDs) and semiconductor lasers can be made that emit in the visible spectrum, or even produce ultraviolet emission. Solid-state lighting could reduce the amount of energy required to provide lighting as compared with incandescent lights, which are associated with a luminous efficacy of less than 20 lumens per watt. The efficacy of LEDs is on the order of 160 lumens per watt. Wide bandgap semiconductors can also be used in RF signal processing. Silicon-based power transistors are reaching limits of operating frequency, breakdown voltage, and power density. Wide bandgap materials can be used in high-temperature and power switching applications. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Wide-bandgap semiconductor」の詳細全文を読む スポンサード リンク
|