|
Rotating Pocket Heater
A rotating pocket heater, also called pocket heater or Kinder heater, holds and rotates a substrate during vacuum deposition. During rotation, the substrate is sequentially exposed to more than one environment, for example, heat, oxygen, metal vapor, etc. Rotating pocket heaters has been used in reactive evaporation system to create YBa2Cu3O7 layers on planar semiconductor wafers. Magnesium diboride The illustration on the right shows an example of a pocket heater being used to deposit a layers of magnesium diboride on a substrate. A vertical shaft (32) turns a horizontal disk (30) several hundred rotations per minute (RPM). The illustration shows two of several substrates (14) attached to the underside of the rotating disk. The substrates are attached at their edges, so that most of the undersides of the substrates are exposed to the vapor below. The entire apparatus is enclosed in a chamber kept at low pressure by a vacuum pump. Magnesium diboride (MgB2) is an ionic solid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (electronics)
In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer. It undergoes many microfabrication processes, such as doping, ion implantation, etching, thin-film deposition of various materials, and photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and packaged as an integrated circuit. History In the semiconductor or silicon wafer industry, the term wafer appeared in the 1950s to describe a thin round slice of semiconductor material, typically germanium or silicon. Round shape comes from single-crystal ingots usually produced using the Czochralski method. Silicon wafers were first introduced in the 1940s. By 1960, silicon wafers were being manufactured in the U.S. by c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Deposition
Vacuum deposition is a group of processes used to deposit layers of material atom-by-atom or molecule-by-molecule on a solid surface. These processes operate at pressures well below atmospheric pressure (i.e., vacuum). The deposited layers can range from a thickness of one atom up to millimeters, forming freestanding structures. Multiple layers of different materials can be used, for example to form optical coatings. The process can be qualified based on the vapor source; physical vapor deposition uses a liquid or solid source and chemical vapor deposition uses a chemical vapor. Description The vacuum environment may serve one or more purposes: * reducing the particle density so that the mean free path for collision is long * reducing the particle density of undesirable atoms and molecules (contaminants) * providing a low pressure plasma environment * providing a means for controlling gas and vapor composition * providing a means for mass flow control into the processing ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planar Process
The planar process is a manufacturing process used in the semiconductor industry to build individual components of a transistor, and in turn, connect those transistors together. It is the primary process by which silicon integrated circuit chips are built. The process utilizes the surface passivation and thermal oxidation methods. The planar process was developed at Fairchild Semiconductor in 1959. Overview The key concept is to view a circuit in its two-dimensional projection (a plane), thus allowing the use of photographic processing concepts such as film negatives to mask the projection of light exposed chemicals. This allows the use of a series of exposures on a substrate (silicon) to create silicon oxide (insulators) or doped regions (conductors). Together with the use of metallization, and the concepts of p–n junction isolation and surface passivation, it is possible to create circuits on a single silicon crystal slice (a wafer) from a monocrystalline silicon boule. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor Wafers
In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer. It undergoes many microfabrication processes, such as doping, ion implantation, etching, thin-film deposition of various materials, and photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and packaged as an integrated circuit. History In the semiconductor or silicon wafer industry, the term wafer appeared in the 1950s to describe a thin round slice of semiconductor material, typically germanium or silicon. Round shape comes from single-crystal ingots usually produced using the Czochralski method. Silicon wafers were first introduced in the 1940s. By 1960, silicon wafers were being manufactured in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotary Pocket Heater Cross Section
Rotary may refer to: General * Rotary motion Engineering and technology * Rotary dial, a rotating telephone dial * Rotary engine (other), multiple types of engines called "rotary" * Rotary latch * Rotary milking shed, a type of milking shed used in the dairy industry * Rotary snowplow, one type of railroad snowplow used especially for deep snow removal * Rotary system, a type of pre-electronic telephone switch * Rotary table (drilling rig), a device used to apply directional force to a drill string * Rotary tiller, a motorised cultivator * Rotary woofer, a type of loudspeaker capable of producing very low frequency sound * Rotary wing aircraft Arts and entertainment * "The Rotary", a song by Andy Partridge from '' Take Away / The Lure of Salvage'' Organisations and enterprises * Rotary International, or Rotary Club, an international service organization founded in the United States ** Rotary Foundation, non-profit foundation of Rotary International ** Rotar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Diboride
Magnesium diboride is the inorganic compound with the formula MgB2. It is a dark gray, water-insoluble solid. The compound has attracted attention because it becomes superconductor, superconducting at 39 K (−234 °C). In terms of its composition, MgB2 differs strikingly from most low-temperature superconductors, which feature mainly transition metals. Its superconducting mechanism is primarily described by BCS theory. Superconductivity Magnesium diboride's superconducting properties were discovered in 2001. Its critical temperature#Superconductivity, critical temperature (''T''c) of is the highest amongst conventional superconductors. Among conventional (BCS theory, phonon-mediated) superconductors, it is unusual. Its electronic structure is such that there exist two types of electrons at the Fermi level with widely differing behaviours, one of them (Sigma bond, sigma-bonding) being much more strongly superconducting than the other (Pi bond, pi-bonding). This is at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiaoxing Xi
Xiaoxing Xi (; born 1957) is a Chinese-born American physicist. He is the Laura H. Carnell Professor and former chair at the Physics Department of Temple University in Philadelphia. In May 2015, the United States Department of Justice arrested him on charges of having sent restricted American technology to China. All charges against him were dropped in September 2015. Career Xi was born in China and received his Ph.D. from Peking University in 1987. He was a researcher at the Karlsruhe Nuclear Research Center in Germany, and moved to the United States in 1989. In the US he worked at Bell Communication Research at Rutgers University and the University of Maryland, before becoming a faculty member of Pennsylvania State University in 1995. He has since naturalized as a US citizen. Xi's wife is also a physics professor, who teaches at Pennsylvania State University. They have two daughters and live in suburban Philadelphia. He was named chairman of Temple University's physics departm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temple University
Temple University (Temple or TU) is a public state-related research university in Philadelphia, Pennsylvania. It was founded in 1884 by the Baptist minister Russell Conwell and his congregation Grace Baptist Church of Philadelphia then called Baptist Temple. On May 12, 1888, it was renamed the Temple College of Philadelphia. By 1907, the institution revised its institutional status and was incorporated as a research university. As of 2020, about 37,289 undergraduate, graduate and professional students were enrolled at the university. Temple is among the world's largest providers of professional education (law, medicine, podiatry, pharmacy, dentistry, engineering and architecture), preparing the largest body of professional practitioners in Pennsylvania. History Temple University was founded in 1884 by Grace Baptist Church of Philadelphia and its pastor Russell Conwell, a Yale-educated Boston lawyer, orator, and ordained Baptist minister, who had served in the Union Army d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
