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Carver Mead
Carver Andress Mead (born 1 May 1934) is an American scientist and engineer. He currently holds the position of Gordon and Betty Moore Professor Emeritus of Engineering and Applied Science at the California Institute of Technology (Caltech), having taught there for over 40 years. A pioneer of modern microelectronics, Mead has made contributions to the development and design of semiconductors, digital chips, and silicon compilers, technologies which form the foundations of modern very-large-scale integration chip design. Mead has also been involved in the founding of more than 20 companies. In the 1980s, Mead focused on electronic modeling of human neurology and biology, creating " neuromorphic electronic systems." Most recently, he has called for the reconceptualization of modern physics, revisiting the theoretical debates of Niels Bohr, Albert Einstein and others in light of later experiments and developments in instrumentation. Mead's contributions as a teacher in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bakersfield, California
Bakersfield is a city in and the county seat of Kern County, California, United States. The city covers about near the southern end of the San Joaquin Valley, which is located in the Central Valley region. Bakersfield's population as of the 2020 Census was 403,455, making it the 47th-most populous city in the United States and the 9th-most populous in California. The Bakersfield–Delano Metropolitan Statistical Area, which includes all of Kern County, had a 2020 census population of 909,235, making it the 62nd largest metropolitan area in the United States. Bakersfield is a significant hub for both agriculture and energy production. Kern County is California's most productive oil-producing county and the fourth most productive agricultural county (by value) in the United States. Industries in and around Bakersfield include natural gas and other energy extraction, mining, petroleum refining, distribution, food processing, and corporate regional offices. The city is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deborah Chung
Deborah Duen Ling Chung (professionally known as D.D.L. Chung, ) is an American scientist and university professor. Early life and education Chung was born and raised in Hong Kong. Her mother was Rebecca Chan Chung (United States World War II veteran with the Flying Tigers and the United States Army in China), whose mother was Lee Sun Chau (one of the first female doctors of Western Medicine in China). Chung studied at Ying Wa Girls' School and King's College (Hong Kong). She moved to the United States in 1970 and received a B.S. degree in Engineering and Applied Science and an M.S. degree in Engineering Science from California Institute of Technology (Caltech) in 1973.About Dr. Chung . University at Buffalo. At Caltech, she conducted research under the supervision of [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field-effect Transistor
The field-effect transistor (FET) is a type of transistor that uses an electric field to control the current through a semiconductor. It comes in two types: junction FET (JFET) and metal-oxide-semiconductor FET (MOSFET). FETs have three terminals: ''source'', ''gate'', and ''drain''. FETs control the current by the application of a voltage to the gate, which in turn alters the conductivity between the drain and source. FETs are also known as unipolar transistors since they involve single-carrier-type operation. That is, FETs use either electrons (n-channel) or holes (p-channel) as charge carriers in their operation, but not both. Many different types of field effect transistors exist. Field effect transistors generally display very high input impedance at low frequencies. The most widely used field-effect transistor is the MOSFET (metal–oxide–semiconductor field-effect transistor). History The concept of a field-effect transistor (FET) was first patented by the Austr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium Arsenide
Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a Zincblende (crystal structure), zinc blende crystal structure. Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circuits, infrared light-emitting diodes, laser diodes, solar cells and optical windows. GaAs is often used as a substrate material for the epitaxial growth of other III-V semiconductors, including indium gallium arsenide, aluminum gallium arsenide and others. History Gallium arsenide was first synthesized and studied by Victor Goldschmidt in 1926 by passing arsenic vapors mixed with hydrogen over gallium(III) oxide at 600 °C. The semiconductor properties of GaAs and other Compound semiconductor, III-V compounds were patented by Heinrich Welker at Siemens-Schuckert in 1951 and described in a 1952 publication. Commercial production of its monocrystals commenced in 1954, and more studies followed in the 195 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterojunction
A heterojunction is an interface between two layers or regions of dissimilar semiconductors. These semiconducting materials have unequal band gaps as opposed to a homojunction. It is often advantageous to engineer the electronic energy bands in many solid-state device applications, including semiconductor lasers, solar cells and transistors. The combination of multiple heterojunctions together in a device is called a heterostructure, although the two terms are commonly used interchangeably. The requirement that each material be a semiconductor with unequal band gaps is somewhat loose, especially on small length scales, where electronic properties depend on spatial properties. A more modern definition of heterojunction is the interface between any two solid-state materials, including crystalline and amorphous structures of metallic, insulating, fast ion conductor and semiconducting materials. Manufacture and applications Heterojunction manufacturing generally requires the use o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Band-gap Engineering
Band-gap engineering is the process of controlling or altering the band gap of a material. This is typically done to semiconductors by controlling the composition of alloys, constructing layered materials with alternating compositions, or by inducing strain either epitaxially or topologically. A band gap is the range in a solid where no electron state can exist. The band gap of insulators is much larger than in semiconductors. Conductors or metals have a much smaller or nonexistent band gap than semiconductors since the valence and conduction bands overlap. Controlling the band gap allows for the creation of desirable electrical properties. Molecular-beam epitaxy (MBE) Molecular-beam epitaxy is a technique used to construct thin epitaxial films of materials ranging from oxides to semiconductors to metals. Different beams of atoms and molecules in an ultra-high vacuum environment are shot onto a nearly atomically clean crystal, creating a layering effect. This is a type of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
III-V Compound Semiconductor
Semiconductor materials are nominally small band gap insulators. The defining property of a semiconductor material is that it can be compromised by doping it with impurities that alter its electronic properties in a controllable way. Because of their application in the computer and photovoltaic industry—in devices such as transistors, lasers, and solar cells—the search for new semiconductor materials and the improvement of existing materials is an important field of study in materials science. Most commonly used semiconductor materials are crystalline inorganic solids. These materials are classified according to the periodic table groups of their constituent atoms. Different semiconductor materials differ in their properties. Thus, in comparison with silicon, compound semiconductors have both advantages and disadvantages. For example, gallium arsenide (GaAs) has six times higher electron mobility than silicon, which allows faster operation; wider band gap, which allows ope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot Electron
Hot commonly refers refer to: *Heat, a hot temperature *Pungency, in food, a spicy or hot quality Hot or HOT may also refer to: Places *Hot district, a district of Chiang Mai province, Thailand ** Hot subdistrict, a sub-district of Hot District, Thailand ** Tha Kham, Chiang Mai, also known as Hot, a town in Hot District, Chiang Mai province, Thailand * Hot, Albania, a village in the Malësi e Madhe municipality, Shkodër County, Albania Music * H.O.T. pronounced "H. O. T.", (High-Five of Teenagers), a South Korean boy band * Hawaii Opera Theatre, an opera company in Honolulu, Hawaii * Hot (American vocal group), best known for 1977 hit "Angel in Your Arms" 1976–1980 Albums * ''Hot'' (James Brown album) or the title song (see below), 1976 * ''Hot'' (Freda Payne album), 1979 * ''Hot'' (Paul Bley album), 1985 * ''Hot'' (Half Japanese album), 1995 * ''Hot'' (Squirrel Nut Zippers album), 1996 * ''Hot'' (Mel B album), 2000 * ''Hot'' (Taeyang EP), or the title song, 2008 * ''Hot'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Tunneling
In physics, quantum tunnelling, barrier penetration, or simply tunnelling is a quantum mechanical phenomenon in which an object such as an electron or atom passes through a potential energy barrier that, according to classical mechanics, should not be passable due to the object not having sufficient energy to pass or surmount the barrier. Tunneling is a consequence of the wave nature of matter, where the quantum wave function describes the state of a particle or other physical system, and wave equations such as the Schrödinger equation describe their behavior. The probability of transmission of a wave packet through a barrier decreases exponentially with the barrier height, the barrier width, and the tunneling particle's mass, so tunneling is seen most prominently in low-mass particles such as electrons or protons tunneling through microscopically narrow barriers. Tunneling is readily detectable with barriers of thickness about 1–3 nm or smaller for electrons, and abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Engineering
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the latter half of the 19th century after the commercialization of the electric telegraph, the telephone, and electrical power generation, distribution, and use. Electrical engineering is divided into a wide range of different fields, including computer engineering, systems engineering, power engineering, telecommunications, radio-frequency engineering, signal processing, instrumentation, photovoltaic cells, electronics, and optics and photonics. Many of these disciplines overlap with other engineering branches, spanning a huge number of specializations including hardware engineering, power electronics, Electromagnetism, electromagnetics and waves, microwave engineering, nanotechnology, electrochemistry, renewable energies, mechatronics/control ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amateur Radio
Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emergency, emergency communications. The term ''"radio amateur"'' is used to specify ''"a duly authorized person interested in radioelectric practice with a purely personal aim and without wikt:pecuniary, pecuniary interest"'' (either direct monetary or other similar reward); and to differentiate it from commercial broadcasting, public safety (police and fire), or two-way radio professional services (maritime, aviation, taxis, etc.). The amateur radio service (''amateur service'' and ''amateur-satellite service'') is established by the International Telecommunication Union (ITU) through their recommended radio regulations. National governments regulate technical and operational characteristics of transmissions and issue individual station li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresno, California
Fresno (; ) is a city in the San Joaquin Valley of California, United States. It is the county seat of Fresno County, California, Fresno County and the largest city in the greater Central Valley (California), Central Valley region. It covers about and had a population of 542,107 as of the 2020 United States census, 2020 census, making it the List of largest California cities by population, fifth-most populous city in California, the most populous inland city in California, and the List of United States cities by population, 34th-most populous city in the nation. Named for the abundant ash trees lining the San Joaquin River, Fresno was founded in 1872 as a railway station of the Central Pacific Railroad before it was Municipal corporation, incorporated in 1885. It has since become an economic hub of Fresno County and the San Joaquin Valley, with much of the surrounding areas in the Metropolitan Fresno region predominantly tied to large-scale agricultural production. Fresno is n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
