A heterojunction is the interface that occurs between two Layer electronics layer s or regions of dissimilar crystalline semiconductor s. These semiconducting materials have unequal band gap s 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 heterotransistors ... where electronic properties depend on spatial properties. A more modern definition of heterojunction ... used in high speed and opto electronics Image Heterojunction types.png 430px thumb right The three ... heterojunctions Image Heterojunction variables in equilibrium.png 360px thumb right The important variables for heterojunction characterization and analysis are defined for two semiconductors physically ... a given junction and understanding the charge dynamics at a heterojunction band gap, electron affinity ... band and the vacuum level. Calculating energy band offsets for an ideal heterojunction is straightforward ... at the heterojunction interface to varying degrees. In cases where both materials have the same ... at heterojunctions When a heterojunction is formed by two different semiconductor s, a quantum well ... state physics effective mass across the heterojunction becomes substantial. The quantum well defined in the heterojunction can be treated as a finite well potential with width of math l w math . Addition ... heterojunctions Image Fe3O4 CdS Nano Heterojunction.JPG 400px thumb right Image of a nanoscale heterojunction .... When a heterojunction is used as the base emitter junction of a bipolar junction transistor ... a heterojunction bipolar transistor HBT . Heterojunctions are used in HEMT high electron mobility transistors ... dopant free region where very little scattering can occur. Fabrication Heterojunction manufacturing ... device fabrication . See also colbegin 3 Anderson s rule Band gap Heterojunction bipolar transistor ... reference respect to applications, but always a good introduction to basic principles of heterojunction ... more details
The heterojunction bipolar transistor HBT is a type of bipolar junction transistor BJT which uses differing semiconductor materials for the emitter and base regions, creating a heterojunction. The HBT improves on the BJT in that it that can handle signals of very high frequencies, up to several hundred gigahertz GHz . It is commonly used in modern ultrafast circuits, mostly radio frequency RF systems, and in applications requiring a high power efficiency, such as RF power amplifiers in cellular phones. The idea of employing a heterojunction is as old as the conventional BJT, dating back to a patent from 1951 ref W. Schockley Circuit Element Utilizing Semiconductive Material , United States Patent 2,569,347, 1951. ref . Materials Image Pnp Heterostructure Bands.png thumb Bands in graded heterojunction npn bipolar transistor. Barriers indicated for electrons to move from emitter to base, and for holes to be injected backward from base to emitter Also, grading of bandgap in base assists electron transport in base region Light colors indicate depletion region depleted regions The principal difference between the BJT and HBT is in the use of differing semiconductor materials for the emitter and base regions, creating a heterojunction. The effect is to limit the injection of holes from the base into the emitter region, since the potential barrier in the valence band is higher than in the conduction band. Unlike BJT technology, this allows a high doping density to be used in the base, reducing the base resistance while maintaining gain. The efficiency of the heterojunction is measured ... up the heterojunction, and can be expressed in the following way formula given ref , named after ... techniques used include MOVPE for III V systems. Limits A pseudomorphic heterojunction bipolar transistor ... Structure Produces World s Fastest Transistor 604 GHz Early 2005 DEFAULTSORT Heterojunction Bipolar ... de Heterojunction bipolar transistor ja HBT pl HBT simple Heterojunction bipolar transistor ... more details
orphan date January 2010 Band offset describes the relative alignment of the energy band s at a semiconductor heterojunction . References Franciosi A. Van de Walle C.G Heterojunction band offset engineering , Surface Science Reports, Volume 25, Number 1, October 1996 , pp. 5 140 136 See also Physics Category Semiconductor structures Category Electronic band structures physics stub ... more details
The Heterojunction emitter bipolar transistor HEBT , is a somewhat unique arrangement with respect to emitter blocking of minority carriers. This is accomplished by using heterostructure confinement in the emitter, introducing an energy barrier to minority carrier charge flow from the base. This is important as loss of minority carriers from the base to the emitter degrades analog signal analog performance. The main difference of the HEBT from the Heterojunction bipolar transistor HBT is that the emitter base interface is the same as in a bipolar junction transistor BJT with the blocking energy gap being moved back into the emitter bulk region. Functional Architecture Image Heterostructure emitter bipolar transistor.jpg thumb HEBT, by Rutherford Research The main advantage of HEBT architecture, compared to the HBT is a simplified fabrication process for the emitter base junction. In particular the HEBT does not require as tight parametric control during epitaxial growth , that equivalent abrupt or graded emitter structures might. This is very important as it is evident from scanning ion mass spectrometry data that out diffusion base dopant into the emitter junction is difficult to control, as the base is, in general, very highly doped in order to enhance performance. Application The HEBT is well positioned as a potential candidate for key roles in high frequency optoelectronic markets, similar to the Heterojunction bipolar transistor . Also of importance for optoelectronic hybrids is that HEBT can be constructed in any semiconductor system that permits the use of band gap altering alloys in the emitter. References doi 10.1016 0038 1101 94 90231 3 doi 10.1088 0268 1242 17 5 301 doi finder http dx.doi.org External links Category Transistor types Category Microwave technology ... more details
Anderson s rule is used for the construction of Electronic band structure energy band diagrams of the heterojunction between two semiconductor material s. It is also referred to as the electron affinity rule. Anderson s rule was first described by R. L. Anderson in 1960 Anderson, 1960 . Anderson s rule states that when constructing an energy band diagram, the Vacuum level vacuum levels of the two semiconductors on either side of the heterojunction should be aligned at the same energy Borisenko and Ossicini, 2004 . The term is also used in the field of computer security for a principle formulated by Ross J. Anderson by their nature large database s will never be free of abuse by breaches of security. If a large system is designed for ease of access it becomes insecure if made watertight it becomes impossible to use ref http www.guardian.co.uk commentisfree henryporter 2009 aug 10 id card database breach Guardian newspaper article on a security breach, in which Anderson s Rule is formulated ref . Using Anderson s rule to construct energy band diagrams Once the vacuum levels are aligned it is possible to use the electron affinity and band gap values for each semiconductor to calculate the conduction band and valence band offsets Davies, 1997 . The electron affinity usually given the symbol math chi math in solid state physics gives the energy difference between the lower edge of the conduction band and the vacuum level of the semiconductor. The band gap usually given the symbol math E g math gives the energy difference between the lower edge of the conduction band and the upper edge of the valence band. Each semiconductor has different electron affinity and band gap values. For semiconductor alloys it may be necessary to use Vegard s law to calculate these values. Once the relative ... band math Delta E c math . Consider a heterojunction between semiconductor A and semiconductor ... . Germanium gallium arsenide heterojunction, IBM J. Res. Dev. 4 3 , pp. 283 287 Borisenko, V. E. and Ossicini ... more details
Other uses Junction disambiguation Junction A Junction , in electricity , may be either a thermoelectricity junction, a metal semiconductor junction or a p n junction p type semiconductor n type semiconductor junction . Junctions are either rectifying or non rectifying. Non rectifying junctions are called Ohmic contact s. Electronic component s employing rectifying junctions include p n diode s, Schottky diode s and bipolar junction transistor s. See also Heterojunction and Homojunction Depletion region , also called junction region Junction voltage p n junction isolation Category Electricity Category Semiconductor structures ... more details
of carbon nanotube heterojunction nanotube heterojunctions , and was first implemented ... the carbon rings needed to produce a heterojunction with arbitrary indices and chirality from two Carbon ... more details
HBT is a three letter initialism that can mean Holistic Body Training Handelsschule Berliner Tor Holy Bible Trivia Holme Bait and Tackle Healthcare Benefit Trust Heritage Bank & Trust Heterojunction Bipolar Transistor Herringbone twill , a type of cloth Hostage Barricade Team Houston Belt and Terminal Railway HydroBall Technics Hydrogen Breath Test HBT explosive HBT , 5,5 hydrazinebistetrazole, an experimental explosive material that is more environmentally friendly than current methods. homosexuality Homosexual , bisexuality Bisexual , and transsexualism Transsexual see LGBT Hanbury Brown and Twiss effect , a variety of correlation and anti correlation effects in the intensity intensities received by two detectors from a beam of particles Harry B. Thompson Middle School Hunter s Bog Trotters , an irreverent Scottish Cross Country, Road, and Fell Running Club based in Edinburgh HBT agar , human blood bilayer Tween 80 agar, used in microbiology as a selective differential human blood bilayer media for isolation of Gardnerella vaginalis disambig de HBT it HBT ... more details
unsourced date December 2007 A homojunction is a semiconductor interface that occurs between layers of similar semiconductor material, these materials have equal band gap s but typically have different doping semiconductor doping . In most practical cases a homojunction occurs at the interface between an n type semiconductor n type donor semiconductors donor doped and p type semiconductor p type acceptor semiconductors acceptor doped semiconductor such as silicon , this is called a p n junction . This is not a necessary condition as the only requirement is that the same semiconductor same band gap is found on both sides of the junction, in contrast to a heterojunction . See also Transistor p n junction Doping semiconductor External links http www.eere.energy.gov basics renewable energy pv cell structures.html Solar cell structures EERE Category Semiconductor structures Category Electronics terms de P n bergang fr H t rojonction pl Homoz cze ru uk ... more details
Refimprove date October 2008 dict A layer is the deposition physics deposition of molecules on a Substrate materials science substrate or base glass , ceramic , semiconductor , or plastic bioplastic . High temperature substrates includes stainless steel and polyimide film expensive ref http www.ipe.uni stuttgart.de index.php?lang ger&pulldownID 12&ebene2ID 18&ID 3394 ref and Polyethylene terephthalate PET cheap . A depth of less than one micrometre is generally called a thin film while a depth greater than one micrometre is called a coating . A web manufacturing web is a flexible disambiguation needed date November 2011 substrate. See also Portal Electronics Coating Heterojunction Nanoparticle Organic electronics Passivation Printed electronics Sputtering Thermal annealing TCO Transparency optics Transparent and Conductive Oxide layer References references Category Semiconductor device fabrication Electron stub ... more details
Jerry Woodall born 1938 is an American inventor and scientist best known for his invention of the first commercially viable heterojunction material GaAlAs for red LED s used in automobile brake lights and traffic lights, CD and DVD players,TV remote controls and computer networks. He is a recipient of US National Medal of Technology and Innovation for his pioneeriong role in the research and development of compound semiconductor materials and devices... ref http www.uspto.gov about nmti recipients 2001.jsp ref Born in Washington, DC, Woodall received a BS in Metallurgy from Massachusetts Institute of Technology in 1960 and a PhD in Electrical Engineering from Cornell University in 1982. References reflist Persondata Metadata see Wikipedia Persondata . NAME Woodall, Jerry ALTERNATIVE NAMES SHORT DESCRIPTION American scientist DATE OF BIRTH 1938 PLACE OF BIRTH DATE OF DEATH PLACE OF DEATH DEFAULTSORT Woodall, Jerry Category 1938 births Category American inventors Category American electrical engineers Category American scientists Category Living people ... more details
date December 2008 SiGe allows CMOS logic to be integrated with heterojunction bipolar transistor s, making it suitable for mixed signal circuits. Heterojunction bipolar transistors have higher ... transistor s. This translates into better low current and high frequency performance. Being a heterojunction ... more details
pairs by effective fields. The effective field are set up by creating a heterojunction between two ..., heterojunction based cells which rely on effective fields are more effective. ref name McGehee ref ... can reach the heterojunction interface. To address this problem, a new type of heterojunction photovoltaic cells is designed, which is the dispersed heterojunction photovoltaic cells. Bulk heterojunction photovoltaic cells File Fig 4 sketch of dispersed junction photovoltaic cell.JPG thumb ... heterojunction photovoltaic cells. Yu et al. fabricated a cell with the blend of MEH PPV and a methano functionalized C sub 60 sub derivative as the heterojunction, ITO and Ca as the electrodes ... blends are also used in dispersed heterojunction photovoltaic cells. Halls et al. used a blend of CN .... Graded Heterojunction photovoltaic cells Deleted image removed File graded heterojunction.jpg ... cell, the electron donor and acceptor are mixed together, like in the bulk heterojunction, but in such as way ... in the dispersed heterojunction with the advantage of the charge gradient of the bilayer technology ref cite web title Graded Heterojunction url http www.license.umn.edu Products Organic Photovoltaic Solar Cells using Graded Heterojunction Technology Z09174.aspx ref . Examples Holmes et al. fabricated ... heterojunction. ref cite journal last Holmes first Russel coauthors Richa Pandey title Organic Photovoltaic ... junction with controlled growth As described in section 2.3, dispersed heterojunction of donor ... acceptor interface inside the bulk of organic thin film. ref name Peumans Controlled growth heterojunction ... in decreased device efficiency. Controlled growth of the heterojunction provides better control ... more details
wiktionary bipolar Bipolar may refer to tocright Medicine Bipolar cell Bipolar cell of the retina Bipolar disorder Bipolar I disorder Bipolar II disorder Bipolar NOS Bipolar spectrum Astronomy Bipolar nebula , a two lobed, axially symmetric nebula Bipolar outflow , outflow of ejected materials from both poles of a star Engineering Bipolar electricity transmission Bipolar encoding Bipolar electric motor Bi Polar locomotive , a locomotive using a bipolar electric motor Bipolar signal Bipolar violation Transistors Bipolar junction transistor BJT Heterojunction bipolar transistor HBT Insulated gate bipolar transistor IGBT Mathematics Bipolar coordinates , a type of orthogonal coordinates based on the Apollonian circles Polar set , sometimes called a bipolar set, is the polar of a polar set Political science Polarity in international relations Bipolarity Bipolarity A situation in which two states have the majority of economic, military, and cultural influence internationally or regionally Music Bi Polar Vanilla Ice album Bipolar Up Dharma Down album Bipolar El Cuarteto de Nos album disambig ca Bipolar da Bipolaritet de Bipolar fr Bipolaire ... more details
wiktionary HJ is a Latin abbreviation for Hic Iacet Here lies , commonly used on gravestones. ref Collins Latin Dictionary & Grammar ref HJ or Hj can mean hj. Hajji , an islamic honorific Handjob , a sexual act Hall Janko group , a mathematical group Halliwell Jones Stadium , a stadium in Warrington Hero s Journey MMORPG , the game by Simutronics Corp. Heterojunction , the interface between two layers of dissimilar crystalline semiconductors Hilal i Jurat , the second highest military award of Pakistan Hitler Jugend , the German name for the Hitler Youth Hobby Japan , Japanese roleplaying, war, and tabletop games, books and magazines publishing company. Hotel juliet , U.S. code word for a cryptographic key change The IATA airline designator for Tasman Cargo Airlines Characters of Watchmen Hooded Justice , a character in The Watchmen Holden HJ , An Australian full sized car produced between 1974 & 1976 Hajj , a pilgrimage to Mecca, Saudi Arabia Notes reflist disambig Category Initialisms de HJ fr HJ ko HJ it HJ sw HJ nl HJ ja HJ fi Hj sv HJ tr HJ ... more details
Aluminium gallium nitride AlGaN is a semiconductor material . It is an alloy of aluminium nitride and gallium nitride . AlGaN is used to manufacture light emitting diode s operating in blue to ultraviolet region, where wavelengths down to 250 nm far UV were achieved. It is also used in blue semiconductor laser s. It is also used in detectors of ultraviolet radiation, and in AlGaN GaN HEMT transistors. AlGaN is often used together with gallium nitride or aluminium nitride , forming heterojunction s. AlGaN layers can be also grown on sapphire . Safety and toxicity aspects The toxicology of AlGaN has not been fully investigated. The AlGaN dust is an irritant to skin, eyes and lungs. The environment, health and safety aspects of aluminium gallium nitride sources such as trimethylgallium and ammonia and industrial hygiene monitoring studies of standard MOVPE sources have been reported recently in a review ref cite journal title Environment, Health and Safety Issues for Sources Used in MOVPE Growth of Compound Semiconductors author Shenai Khatkhate, D. V. Goyette, R. DiCarlo, R. L. Jr. and Dripps, G. journal Journal of Crystal Growth volume 272 issue 1 4 pages 816 821 year 2004 doi 10.1016 j.jcrysgro.2004.09.007 ref . References reflist External links DEFAULTSORT Aluminium Gallium Nitride Category Semiconductor materials Category Aluminium compounds Category Gallium compounds Category Nitrides Category III V compounds Category Light emitting diode materials ar fr Nitrure d aluminium et de gallium ... more details
Orphan date February 2009 electronic structure methods The model solid approximation is a method used for determining the extrema of energy bands in semiconductors . The method was first proposed for silicon germanium alloys by Chris G. Van de Walle and Richard M. Martin in 1986 ref citation last Van de Walle first Chris G. last2 Martin first2 Richard M. journal Phys. Rev. B volume 34 issue 8 date 1986 10 15 page 5621 title Theoretical calculations of heterojunction discontinuities in the Si Ge system bibcode 1986PhRvB..34.5621V doi 10.1103 PhysRevB.34.5621 ref and extended to several other semiconductor materials by Van de Walle in 1989. ref citation last Van de Walle first Chris G. journal Phys. Rev. B volume 39 issue 3 date 1989 01 15 page 1871 title Band lineups and deformation potentials in the model solid theory bibcode 1989PhRvB..39.1871V doi 10.1103 PhysRevB.39.1871 ref It has been used extensively for modelling semiconductor heterostructure devices such as quantum cascade lasers . ref citation last Faist first J r me last2 Capasso first2 Federico last3 Sivco first3 Deborah L. last4 Hutchinson first4 Albert L. last5 Chu first5 Sung Nee G. last6 Cho first6 Alfred Y. Cho journal Appl. Phys. Lett. volume 72 issue 6 date 1998 02 09 page 680 title Short wavelength 3.4 m quantum cascade laser based on strained compensated InGaAs AlInAs bibcode 1998ApPhL..72..680F doi 10.1063 1.120843 ref Although the electrostatic potential in a semiconductor crystal fluctuates on an atomic scale, the model solid approximation averages these fluctuations out to obtain a constant energy level for each material. References reflist Category Semiconductor material structures condensedmatter stub ... more details
Nofootnotes date August 2010 Nihongo Satoshi Hiyamizu Hiyamizu Satoshi is a Japanese professor of electrical engineering . Dr. Hiyamizu won the 1982 Japanese Journal of Applied Physics Paper Award as lead author of a paper on mobility in 2DEG two dimensional electron gases while at Fujitsu Laboratories Limited, received the 1990 IEEE Morris N. Liebmann Memorial Award with Takashi Mimura for outstanding contributions to the epitaxy epitaxial growth of compound semiconductor materials and devices, and in 2001 was named an IEEE Fellow for contributions to the realization of the first high electron mobility transistor HEMT . He served as dean of the Osaka University Graduate School of Engineering from 2000 to 2002. References Satoshi Hiyamizu et al., Extremely High Mobility of Two Dimensional Electron Gas in Selectively Doped GaAs N AlGaAs Heterojunction Structures Grown by MBE , Jpn. J. Appl. Phys. Vol.20 1981 Pt.2 No.4, pp. L245 L248. http www.ieee.org documents liebmann rl.pdf IEEE Morris N. Liebmann Memorial Award recipients http www.ieeec.com membership services membership fellows chronology fellows 2001.html IEEE Fellow Class of 2001 http www.ieee jp.org section tokyo fellow winner fellow01.htm IEEE Fellow Class of 2001 Tokyo section http www.es.osaka u.ac.jp eng intro history.html Osaka University Graduate School of Engineering history Persondata Metadata see Wikipedia Persondata . NAME Hiyamizu, Satoshi ALTERNATIVE NAMES SHORT DESCRIPTION DATE OF BIRTH PLACE OF BIRTH DATE OF DEATH PLACE OF DEATH DEFAULTSORT Hiyamizu, Satoshi Category Japanese electrical engineers Category Living people Category Osaka University alumni Category Osaka University faculty ... more details
ocmweb projects Organic WORM worm.htm Organic inorganic heterojunction WORM memory ref ref ... Smith and Forrest A low switching voltage organic on inorganic heterojunction memory element utilizing ... more details
The modulated doping field effect transistor or modulation doped field effect transistor MODFET is a type of a field effect transistor , also known as the High Electron Mobility Transistor HEMT . Like other FETs, MODFETs are used in integrated circuits as digital on off switches. FETs can also be used as amplifiers for large amounts of current using a small voltage as a control signal. Both of these uses are made possible by the FET s unique current voltage characteristic s. Manufacture MODFETs can be manufactured by epitaxial growth of a strained SiGe layer. In the strained layer, the germanium content increases linearly to around 40 50 . This concentration of germanium allows the formation of a quantum well structure with a high conduction band offset and a high density of very mobile charge carrier s. The end result is a FET with ultra high switching speeds and low noise. InGaAs AlGaAs , AlGaN InGaN , and other compounds are also used in place of SiGe. InP and GaN are starting to replace SiGe as the base material in MODFETs because of their better noise and power ratios. Conceptual analysis MODFETs are heterojunction s. This means that the semiconductors used have dissimilar band gap s. For instance, silicon has a band gap of 1.1 electron volt s eV , while germanium has a band gap of .67 eV. When a heterojunction is formed, the conduction band and valence band throughout the material must bend in order to form a continuous level. MODFETs exceptional electron mobility carrier mobility and switching speed come from the following conditions. The wide band element is doped with donor atoms thus it has excess electron s in its conduction band. These electrons will diffuse to the adjacent narrow band material s conduction band due to the availability of states with lower energy. The movement of electrons will cause a change in potential and thus an electric field between the materials. The electric field will push electrons back to the wide band element s conduction ba ... more details
A two dimensional electron gas 2DEG is a gas of electron s free to move in two dimensions, but tightly confined in the third. This tight confinement leads to quantized energy level s for motion in that direction, which can then be ignored for most problems. Thus the electrons appear to be a 2D sheet embedded in a 3D world. The analogous construct of electron hole holes is called a two dimensional hole gas 2DHG , and such systems have many useful and interesting properties. Geometries Image FET cross section.png thumb right 250px In MOSFETs, the 2DEG is only present when the transistor is in inversion mode, and is found directly beneath the gate oxide. Image HighElectronMobilityTrasistor Band Image.PNG thumb right 250px Energy Band of basic HEMT. Most 2DEGs are found in transistor like structures made from semiconductor s. The most commonly encountered 2DEG is the layer of electrons found in MOSFET s. When the transistor is in inversion mode , the electrons underneath the gate oxide are confined to the semiconductor oxide interface, and thus occupy well defined energy levels. Nearly always, only the lowest level is occupied, and so the motion of the electrons perpendicular to the interface can be ignored. However, the electron is free to move parallel to the interface, and so is quasi two dimensional. Other methods for engineering 2DEGs are HEMT high electron mobility transistor s HEMTs and rectangular quantum well s. HEMT s are field effect transistors that utilize the heterojunction between two semiconducting materials to confine electrons to a triangular quantum well . Electrons confined to the heterojunction of HEMTs exhibit higher electron mobility mobilities than those in MOSFETs, since the former device utilizes an intentionally undoped channel thereby mitigating the deleterious effect of ionized impurity scattering . Two closely spaced heterojunction interfaces may be used to confine electrons to a rectangular quantum well . Careful choice of the materials an ... more details
. Features 3D molecular viewer Structure generation of Carbon nanotube Heterojunction carbon nanotube ... nanotube. Heterojunction generation This is the core of the CoNTub Contub note 0 sup 1 sup ... more details
of the first heterojunction bipolar transistor laser by incorporating a quantum well in the active ... . In 2006, American Institute of Physics selected Room Temperature Continuous Wave Operation of a Heterojunction ... more details
wiktionary junction TOCright Junction may refer to Electricity Junction electricity Thermoelectricity junction, a metal metal junction Metal semiconductor junction p n junction , or semiconductor semiconductor junction Magnetic tunnel junction Rectifying junction Ohmic contact , a non rectifying junction Heterojunction Homojunction Depletion region , also called junction region Junction voltage Junction diode Junction transistor disambiguation p n junction isolation Junction box , a container for electrical connections, usually intended to conceal them from sight and meter tampering Other science and technology Cell junction , in biology NTFS junction point , in computing A construct of the computer language Perl 6 called Perl 6 Junctions Junctions Transport Junction traffic where traffic routes cross Junction road , a road junction Intersection road , a road junction Interchange road , a motorway junction Junction canal , a canal junction Junction rail , a railroad railway junction Places Junction is also the name of some places in the United States Junction, California disambiguation Junction, Contra Costa County, California Junction, California, former name of Junction House, Lassen County, California Junction, Mendocino County, California Junction, California, former name of Roseville, California , in Placer County Junction, Illinois Junction, Texas Junction, Utah Junction, Wisconsin and at least one in England Junction, North Yorkshire Junction City is also a popular name Junction City, Arkansas Junction City, Georgia Junction City, Illinois Junction City, Kansas Junction City, Kentucky Junction City, Louisiana Junction City, Missouri Junction City, Ohio Junction City, Oregon Junction City, Washington Junction City, Wisconsin Grand Junction is also the name of a few places Grand Junction, Colorado Grand Junction, Iowa Grand Junction, Michigan Grand Junction, Tennessee Popular culture Junction Dune , a fictional planet in the Dune universe a Guardian Force junct ... more details
Indium gallium phosphide InGaP , also called gallium indium phosphide GaInP , is a semiconductor composed of indium , gallium and phosphorus . It is used in high power and high frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide . It is used mainly in HEMT and Heterojunction bipolar transistor HBT structures, but also for the fabrication of high efficiency solar cells used for space applications and, in combination with aluminium Aluminium gallium indium phosphide AlGaInP alloy to make high brightness LED s with orange red, orange, yellow, and green colors. Indium gallium phosphide is an alloy of indium phosphide and gallium phosphide . Special importance is an alloy of Ga sub 0.5 sub In sub 0.5 sub P, which is almost lattice matched to GaAs . This allows, in combination with Al sub x sub Ga sub 1 x sub sub 0.5 sub In sub 0.5 sub , the growth of Lattice constant lattice matched quantum well s for red emitting Laser diode semiconductor lasers , e.g. red Solid state lighting emitting 650 1 E 9 m nm RCLED s or VCSEL s for Poly methyl methacrylate PMMA plastic optical fiber s. Ga sub 0.5 sub In sub 0.5 sub P is used as the high energy junction on double and triple junction photovoltaic cells grown on GaAs . Recent years have shown GaInP GaAs tandem solar cells with AM0 sunlight incidence in space 1.35 kW m sup 2 sup efficiencies in excess of 25 . ref http www.cam.uh.edu MQW 20tech 202p.php ref A different alloy of GaInP, lattice matched to the underlying GaInAs , is utilized as the high energy junction GaInP GaInAs Ge triple junction photovoltaic cells. Growth of GaInP by epitaxy can be complicated by the tendency of GaInP to grow as an ordered material, rather than a truly random alloy. This changes the bandgap and the electronic and optical properties of the material. See also Gallium phosphide Indium III phosphide Indium gallium nitride Indium gallium arsenide GaInP GaAs solar cel ... more details
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