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United States Patent: 5,206,526 The period compositional variation in the superlattice region is such that each period lacks reflection symmetry in any plane parallel to the surface, whereby absorption of photons in the superlattice region can result in the appearance of a voltage across the superlattice region. Among these is ion bombardment of the superlattice region to introduce lattice defects, growth of the material of the superlattice region (e.g., by MBE) at relatively low temperature, or by stimulated recombination in predetermined portions of the superlattice region. Superlattice structures according to the invention can be readily produced by known means, e.g., by MBE growth of Al.sub.1-x Ga.sub.x As on a GaAs substrate, with x varied to result in the desired grading or step-like variation. www.ece.sunysb.edu /~serge/pat15.html   (4199 words)

U.S. Patent: 6005259 - InAs/GaSb superlattice structure infrared detector fabricated by organometallic vapor phase ... An InAs/GaSb superlattice infrared detector prepared on a GaSb or a GaAs substrate by low pressure organometallic chemical vapor deposition, the V to III ratio of the InAs superlattice layer is 28.7 and the V to III ratio of the GaSb layer is 78.5. The V to III ratio of the InAs supperlattice layer is 28.7 and the V to III ratio of the GaSb layer is 78.5. The V to III ratio of the GaSb superlattice structure is 75.5 and 28.7 for the V to III ratio of InAs. www.everypatent.com /comp/pat6005259.html   (1620 words)

U.S. Patent: 5536948 - Infrared detector element substrate with superlattice layers - July 16, 1996 Each superlattice layer of the present invention preferably comprises 10-15 pairs of two thin sublayers of semiconductor alloys (gallium antimonide and aluminum antimonide for the matched superlattice sublayers and gallium antimonide and indium arsenic antimonide for the strain superlattice sublayers). Thus, a defect filter, comprised of two different types of superlattice layers, is disposed intermediate the base 10 and the detector elements 16 so as to mitigate the propagation of defects from the crystalline base layer 10 to the individual infrared detector elements 16, thereby reducing their performance. In the preferred embodiment of the present invention the strain superlattice layer is formed directly upon the substrate and the matched superlattice layer is formed upon the strain superlattice layer. www.everypatent.com /comp/pat5536948.html   (3579 words)

Superlattice field effect transistor with monolayer confinement - Patent 5049951 The HFET of claim 1 wherein the superlattice comprises a plurality of quantum well layers which are sized to provide a quantized potential energy gradient between the channel layer and the substrate. The superlattice structure was relied on for its mechanical properties and little attention was directed towards using solid state electronic properties of the superlattice. Superlattice buffer 12 usually comprises layers of material such as gallium arsenide (GaAs) alternating with layers of aluminum arsenide (AlAs). www.freepatentsonline.com /5049951.html   (3678 words)

Interfacial Thermal Resistance in Superlattice Structures   (Site not responding. Last check: 2007-11-02) Figure 2 illustrates the temperature gap that arises in a krypton-argon-krypton structure in which each film is 8 atomic planes thick; a heat flux is imposed across the structure and the steady state time averaged temperature of each atomic plane is recorded. For complex superlattices of more than three films, it is expected that the interaction among interfaces will result in a more erratic response than in the simple dual interface case. Thin film thickness, atomic scale defects (imperfections and dislocations), superlattice periodicity and temperature will influence the shape of the dispersion curve and the size of the frequency gap and thereby affect the heat transport across the structure. www.me.berkeley.edu /mhtl/md-alexis.html   (491 words)

Semiconductor superlattice structures have shown promise as thermoelectric materials for their high power factor and ... A superlattice is a periodic structure generally consisting of several to hundreds of alternating thin film layers where each layer is typically between 10 and 500 Angstroms thick. Superlattices are grown either by Molecular Beam Epitaxy (MBE) or Metal Organic Chemical Vapor Deposition (MOCVD) to ensure high quality films. Phonon transport in semiconductor superlattices is controlled by two mechanisms: interface scattering by acoustic impedance mismatch, defects and/or roughness, and phonon filtering by Bragg reflection. www.me.berkeley.edu /mtpl/super.html   (598 words)

Wave packets in a semiconductor superlattice First, the superlattice bandstructure and the envelope functions of the superlattice, zone-center eigenstates are calculated. The bandstructure formalism describes superlattices with a variety of growth orientations and accounts for the effects of lattice mismatch within the superlattice and applied stress or DC electric fields. The wave packet description of the superlattice coherent dynamics is an effective means for modelling the interference effects that arise between superlattice subband states that are simultaneously excited by a short laser pulse. www.optics.rochester.edu /~stroud/thesis/biermann.html   (335 words)

Superlattice Ordering of Mn, Ni, and Co in Layered Alkali Transition Metal Oxides with P2, P3, and O3 Structures Superlattice Ordering of Mn, Ni, and Co in Layered Alkali Transition Metal Oxides with P2, P3, and O3 Structures Using X-ray and neutron diffraction, it is shown that increasing amounts of Co first weaken and then suppress the superlattice ordering in the transition metal layers. The necessary conditions for superlattice ordering of transition metal atoms in the transition metal layers are discussed. pubs.acs.org /cgi-bin/abstract.cgi/cmatex/2000/12/i12/abs/cm000359m.html   (238 words)

Superlattice and Negative Differential Conductivity in Semiconductors   (Site not responding. Last check: 2007-11-02) We consider a one-dimensional periodic potential, or "superlattice," in monocrystalline semiconductors formed by a periodic variation of alloy composition or of impurity density introduced during epitaxial growth. If the period of a superlattice, of the order of 100 Å, is shorter than the electron mean free path, a series of narrow allowed and forbidden bands is expected due to the subdivision of the Brillouin zone into a series of minizones. The study of superlattices and observations of quantum mechanical effects on a new physical scale may provide a valuable area of investigation in the field of semiconductors. domino.research.ibm.com /tchjr/journalindex.nsf/1be2fd38b451963885256547004c00c8/c8a7ed853d5dce1b85256bfa0068407a?OpenDocument   (109 words)

Block-by-Block Growth of Single-Crystalline Si/SiGe Superlattice Nanowires   (Site not responding. Last check: 2007-11-02) While there are a number of well-developed techniques (e.g., molecular beam epitaxy) for the fabrication of thin film heterostructures and superlattices, a general synthetic scheme for heterojunction and superlattice formation in 1D nanostructures with well-defined coherent interfaces is currently still lacking. The periodic modulation of Ge doping is further confirmed by scanning a focused electron beam along the nanowire growth axis and tracking the change of X-ray signal from Si and Ge atoms in the wires (Figure 2d). The concentration of Ge in the superlattice is controlled by the ratio of Ge atoms and Si atoms deposited into the alloy droplets. pubs.acs.org /cgi-bin/sample.cgi/nalefd/2002/2/i02/html/nl0156888.html   (2298 words)

Citebase - On the nature of the negative-conductivity resonance in a superlattice Bloch oscillator   (Site not responding. Last check: 2007-11-02) Adding a high-frequency ac component to the bias field of a superlattice induces a synchronous modulation of the velocity with which the electrons traverse the Brillouin zone. We analyze the current dynamics of a superlattice Bloch oscillator under conditions where, in addition to the dc bias field causing a negative differential ac conductivity, a similarly strong ac field is present, at a frequency somewhat below the Bloch frequency associated with the dc field. Superlattice is subjected to a microwave field and a generation is achieved at some odd harmonics of... www.citebase.org /cgi-bin/citations?id=oai:arXiv.org:cond-mat/0007482   (4202 words)

Method of making a superlattice heterojunction bipolar device - Patent 4937204 A method of forming a superlattice device as recited in claim 1 wherein the steps of forming the superlattice structure comprise repeating the forming steps until the thickness of the superlattice structure is between 1300 to 2500.ANG. The resulting structure has the special property of a de-localized state of the electron and a localized state of the LO phonon (longitudinal optical phonon) with respect to the laminated layer direction in each semiconductor layer which allows the electron mobility to be modulated by the mutual action therebetween. Further, parts of the semiconductor layers 9, 8, 7 and 6 are removed by etching to expose to the outside a part of the collector layer 4 on which a collector electrode is deposited in ohmic contact and an emitter electrode 12 is deposited on the emitter region 9 in ohmic contact. www.freepatentsonline.com /4937204.html   (2396 words)

ILL : ANNUAL REPORT 2000   (Site not responding. Last check: 2007-11-02) Rare earth superlattices have been studied intensely over the last decade using elastic neutron scattering to determine their magnetic structures [4]. Q is parallel to the Dy c-axis and the superlattice growth direction. This superlattice period L, which is the sum of the individual Dy and Y layer thicknesses, is expected to induce a folding of the Brillouin zone like in the case of phonons in superlattices [10] or graphite intercalated compounds [11]. www.ill.fr /AR-00/p-26.htm   (1310 words)

Nextreme Thermal Solutions - Superlattice Material   (Site not responding. Last check: 2007-11-02) Nextreme's devices employ nanoengineered layered semiconductors called superlattices that are created by stacking thousands of layers of thermoelectric material, with the layers between 1 and 5 nanometers thick (1 nm ~ 1/10,000th the thickness of a human hair). The superlattice material allows more efficient transfer of heat and energy than conventional solutions. The thin-film superlattices and microelectronic fabrication lead to small, high-speed, devices that have no moving parts and offer the high reliability of solid-state devices. www.nextremethermal.com /pages/tech/super.html   (166 words)

Georgia Institute of Technology :: News Room :: Nanohelix Structure Provides New Building Block   (Site not responding. Last check: 2007-11-02) Based on a superlattice composed of alternating single-crystal “stripes” just a few nanometers wide, the “nanohelix” structure is part of a family of nanobelts – tiny ribbon-like structures with semiconducting and piezoelectric properties – that were first reported in 2001. Nanosprings are composed of a single crystal whose shape is governed by balancing the electrostatic forces created by opposite electrical charges on their edges with the elastic deformation energy of the entire structure. The superlattice nanobelt is a periodic, coherent, epitaxial and parallel assembly of two alternating stripes of zinc oxide crystals oriented with their c-axes perpendicular to one another. www.gatech.edu /news-room/release.php?id=639   (1284 words)

Optical characteristics of InAs quantum dots influenced by AlGaAs/GaAs superlattice barriers We investigated the effect of AlGaAs/GaAs superlattice barriers on the optical properties of InAs quantum dots (QDs) by using photoluminescence (PL) spectroscopy. In order to identify the effect superlattice barrier, simple GaAs/InAs QD/GaAs structure was also grown as a reference. However, the PL intensity was drastically decreased with large broadening in PL linewidth from 44 meV to 75 and 80 meV for the ground state. www.nsti.org /Nanotech2003/showabstract.html?absno=636   (300 words)

1-dimensional superlattice? I haven't done much in the way of IC design and whatnot, but I don't recognize superlattices as being a part of the design. To be perfectly honest, I don't even know what a superlattice is beyond a textbook definition, and I don't understand how one (or anything outside of string theory or some other exotic situation, for that matter) can be one-dimensional. I just wanted to get some clarification on what exactly a 1-dimensional superlattice is. I apologise if this kind of thing is inappropriate for these forums. www.physicsforums.com /showthread.php?p=958718#post958718   (735 words)

Talk Abstract:Superlattice Turing Patterns: Why Not?   (Site not responding. Last check: 2007-11-02) ``Superlattice patterns'' are characterized as having spatial structure on two disparate length scales; they are spatially-periodic on the large scale, and have beautiful intricate structure on the smaller scale. Such patterns were recently observed in experiments on parametrically-excited surface waves by Kudrolli, Pier and Gollub. By considering a particular degenerate bifurcation problem we are able to show that the transitions observed in the hydrodynamic problem cannot be reproduced in the chemical reaction-diffusion system. www.ima.umn.edu /dynsys/wkshp_abstracts/silber1.html   (122 words)

Multispectral radiation detectors using strain-compensating superlattices (US6455908) A multispectral radiation detector for detecting radiation in at least two spectral bands, comprises a substrate and a layer stack grown on the substrate. The layer stack comprises at least first and second photodiodes, each photodiode having at least one strain-compensating superlattice absorbing layer substantially lattice matched to adjacent layers of the detector. Each strain-compensating superlattice absorbing layer has an energy gap responsive to radiation energy in a corresponding spectral region and different from the energy gaps of other strain-compensating superlattice absorbing layers of the detector. www.delphion.com /details?pn=US06455908__   (287 words)

Nano Superlattice Technology, Inc. Announces the Retainer of Festo AG & Co. to Construct Sophisticated Robotic ... Nano Superlattice Technology, Inc. Announces the Retainer of Festo AG & Co. to Construct Sophisticated Robotic Automation Insertion Machinery to Be Used in Nano Coating Process About Nano Superlattice Technology Inc. Nano utilizes Arc Bond Sputtering and Superlattice technology to apply multi-layers of super-hard elemental coatings on an array of precision products to achieve a variety of physical properties. The application of the coating on industrial products is designed to change their physical properties, improving an individual product's durability, resistance, chemical and physical characteristics as well as performance. www.prnewswire.com /cgi-bin/stories.pl?ACCT=104&STORY=/www/story/03-29-2006/0004329222&EDATE=   (386 words)

Field effect devices having short period superlattice structures using Si and Ge (US5357119) Carrier mobility in a heterojunction field effect device is increased by reducing or eliminating alloy scattering. The active channel region of the field effect device uses alternating layers of pure silicon and germanium which form a short period superlattice with the thickness of each layer in the superlattice being no greater than the critical thickness for maintaining a strained heterojunction. The gate contact of the field effect device can comprise quantum Si/Ge wires which provide quantum confinement in the growth plane, thereby allowing the field effect device to further improve the mobility by restricting phonon scattering. www.delphion.com /details?pn=US05357119__   (471 words)

Nano Superlattice (NSLT) Stock Charts - Technical Analysis and Charting Make Nano Superlattice your first of 30 commission free trades. InvestorGuide's Interactive Charting offers you the ability to investigate historical trends of Nano Superlattice stock price and compare the performance of Nano Superlattice to several well-known benchmarks. We have gathered all of the important information into one simple tool so that you can research any company you like quickly and easily, whether you are an expert stock researcher or a beginner investor. www.investorguide.com /stock-charts.cgi?ticker=NSLT   (505 words)

Nano Superlattice Technology, Inc. Announces the Retainer of Festo AG & Co. to Construct Sophisticated Robotic ...   (Site not responding. Last check: 2007-11-02) Nano Superlattice Technology, Inc. Announces the Retainer of Festo AG and Co. to Construct Sophisticated Robotic Automation Insertion Machinery to be used in Nano Coating Process - Public Companies News from Send2Press Newswire Wed, 29 Mar 2006 Nano Superlattice Technology, Inc. Announces the Retainer of Festo AG and Co. to Construct Sophisticated Robotic Automation Insertion Machinery to be used in Nano Coating Process Nano utilizes Arc Bond Sputtering and Superlattice technology to apply multi-layers of super-hard elemental coatings on an array of precision products to achieve a variety of physical properties. www.send2press.com /newswire/2006-03-0329-002A.shtml   (1368 words)

Thin-Film Superlattice Technology - RTI International RTI's material cools so efficiently that applying tiny dots of it to just the hot spots on a microprocessor chip would result in better performance than trying to cool the whole chip and would consume less power. RTI's superlattice devices are 2.4 times more efficient and 23,000 times faster than existing thermoelectric devices, enabling "anywhere, anytime" cooling. These high-speed, more-efficient solid-state heat pumps represent a step up in the state of the art, using the advantages of microelectronic wafer-scalability, high-performance materials, and high speed. www.rti.org /page.cfm?nav=86&objectid=D3154009-28BE-4DBF-B8EC541532F03B4B   (331 words)

Stock Research Wizard - Catalysts - MSN Money Look for press releases on new products, partnerships, strategies or problems that might improve or diminish the company's chances of success, and for news reports on new products, strategies, alliances or trouble. Companies must disclose all material facts about their businesses to federal regulators every 3 months. Advisor FYI Alerts provide investors with highlights of catalyst information like changes in analyst projections or changes in the financial condition of the company. moneycentral.msn.com /investor/research/wizards/SRWCatalysts.asp?Symbol=NSLT   (261 words)

Transport Properties of the Semiconductor Superlattice Precise calculations have been made, by Monte Carlo methods, of electron transport properties of the Esaki superlattice. The calculations were on a single-particle space-homogeneous basis, with a model of the superlattice which could be reasonably close to reality. Related Subjects: Carrier transport; Mathematics; Physics, solid state; Physics, theoretical; Semiconductor devices; Superlattices domino.research.ibm.com /tchjr/journalindex.nsf/0b9bc46ed06cbac1852565e6006fe1a0/6beb9d22a561455e85256bfa0068418f?OpenDocument   (120 words)

NANO SUPERLATTICE TECHNOLOGY INC. - NSLT Unscheduled Material Events (8-K) EXHIBIT 2.1 This Share Exchange Agreement, dated as of May 26, 2004, is made by and among NANO SUPERLATTICE TECHNOLOGY, Inc., a Delaware corporation (the "Acquiror"), Mr. Alice Tzu-Hsia Hwang (the "Shareholder Representative"), for and on behalf of each of the Persons listed on Exhibit A hereto (collectively, the "Shareholders", and individually a "Shareholder"), and Nano Superlattice Technology Inc., a British Virgin Islands company (the "Company"). Nano Superlattice Technology, Inc. Loeb and Loeb, LLP Miao LiCity 345 Park Avenue Chung Cheng Road #449 New York, NY 10154 Taiwan, ROC Attention: Mitchell S. Nussbaum, Esq. sec.edgar-online.com /2004/06/07/0001165527-04-000134/section5.asp   (9138 words)

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