WO2001000522A2 - Nanometer-scale modulation - Google Patents
Nanometer-scale modulation Download PDFInfo
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- WO2001000522A2 WO2001000522A2 PCT/DK2000/000348 DK0000348W WO0100522A2 WO 2001000522 A2 WO2001000522 A2 WO 2001000522A2 DK 0000348 W DK0000348 W DK 0000348W WO 0100522 A2 WO0100522 A2 WO 0100522A2
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01Q—SCANNING-PROBE TECHNIQUES OR APPARATUS; APPLICATIONS OF SCANNING-PROBE TECHNIQUES, e.g. SCANNING PROBE MICROSCOPY [SPM]
- G01Q40/00—Calibration, e.g. of probes
- G01Q40/02—Calibration standards and methods of fabrication thereof
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/20—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy
- H01L21/2003—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy characterised by the substrate
- H01L21/2007—Bonding of semiconductor wafers to insulating substrates or to semiconducting substrates using an intermediate insulating layer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/04—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by their crystalline structure, e.g. polycrystalline, cubic or particular orientation of crystalline planes
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/122—Single quantum well structures
- H01L29/125—Quantum wire structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/122—Single quantum well structures
- H01L29/127—Quantum box structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/02—Semiconductor bodies ; Multistep manufacturing processes therefor
- H01L29/12—Semiconductor bodies ; Multistep manufacturing processes therefor characterised by the materials of which they are formed
- H01L29/15—Structures with periodic or quasi periodic potential variation, e.g. multiple quantum wells, superlattices
- H01L29/158—Structures without potential periodicity in a direction perpendicular to a major surface of the substrate, i.e. vertical direction, e.g. lateral superlattices, lateral surface superlattices [LSS]
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/30—Structure or shape of the active region; Materials used for the active region
- H01S5/34—Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers
- H01S5/341—Structures having reduced dimensionality, e.g. quantum wires
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S5/00—Semiconductor lasers
- H01S5/30—Structure or shape of the active region; Materials used for the active region
- H01S5/34—Structure or shape of the active region; Materials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers
- H01S5/341—Structures having reduced dimensionality, e.g. quantum wires
- H01S5/3412—Structures having reduced dimensionality, e.g. quantum wires quantum box or quantum dash
Definitions
- the present invention relates to techniques for fabricating artificial periodic structures in crystals and at crystal interfaces and surfaces.
- the present invention relates to techniques for fabricating nanometer-scale periodic strain patterns near the interface between two crystals, where the strain extends some distance away from the interface.
- the present invention further relates to the use of such strain patterns to generate a regular lattice of quantum dots or quantum wires for applications in electronic, optoelectronic and magnetic device fabrication.
- the present invention even further relates to the use of such strain patterns to generate a regular nanoscale lattice of controlled period at or near the free surface of a crystal for applications in diffractive optical systems, metrology and crystal growth.
- lithographic techniques have serious limitations.
- Optical lithography has limitations mainly in terms of the smallest feature sizes that can be generated, which due to diffraction effects are not smaller than half the wavelength of the light used, and in practice are considerably larger than this diffraction limit.
- grating like modulation of GaAs/AIGaAs quantum wells has been achieved by use of an interference pattern from a laser, but the period of the fringes was limited to 2 ⁇ m using 532 nm laser light.
- Electron beam lithography can be used to make features with smaller periods.
- the technology is slow if large areas on a surface must be patterned.
- the regularity of the periodic pattern can be limited by aberrations of the electron optics.
- Messica et al describe an array of 25 metallic wires with a period of 1 00 nm formed by e-beam lithography.
- this method is limited by the wavelength of the surface acoustic waves that can be generated (typically several microns), and is in any case cumbersome, as it requires external power to maintain the modulation.
- Quantum wires and dots have dimensions in the range of 1 -100 nm to provide sufficient confinement of electrons so that the desired quantisation effects are detectable at room temperature.
- Quantum wires induced by periodic strain have been made by the technique of cleaved-edge overgrowth.
- the periodic strain structure can be fabricated to extend some significant distance away from the interface, of order 1 -1 0 nm, and that this depth is controllable.
- the regularity of the fabricated periodic structure which is given by the regularity of the crystal lattices on either side of the interface, may be extremely high.
- the present invention relates to an article comprising :
- a first group of crystalline elements being formed by the same material and having a predetermined first crystal axis
- a second group of crystalline elements being formed by the same material and having a predetermined second crystal axis being different from the first crystal axis
- first and second group of crystalline elements are adjacently positioned so as to form an interface region between the first and second group of crystalline elements, at least part of said interface region defining a substantially periodic pattern extending in at least one direction.
- the material forming the first group of crystalline elements may comprise a semiconductor material, such as silicon or gallium arsenide.
- the material forming the second group of crystalline elements may comprise a semiconductor material, such as silicon or gallium arsenide.
- the materials forming the first and second group of crystalline elements may comprise an insulator material, such as diamond or sapphire.
- the orientation of the crystal axes of the two wafers may differ in two different ways. There may be a twist angle between the crystal axes such that the in-plane axes of first crystal axis are rotated an angle ⁇ relative to second crystal axis at the time of bonding.
- ⁇ There may also be a tilt angle ⁇ the crystal axes. This can be achieved by cutting the surface of one of the crystals at a tilt angle ⁇ to the main crystal axes in the direction normal to the surface.
- the tilt and twist of interest are typically in the range 0 degrees to 20 degrees, and in particular small angles in the range 0 degrees to 5 degrees. At larger angles, tilt is usually described in terms of the crystal facet index. At larger twist angles, the periodic interface structure is usually described in terms of coincidence site lattices.
- the first crystal axis may differ from the second crystal axis by a twist angle ⁇ , where ⁇ may be within the range 0, 1 -1 0°, such as in the range 0,2-9°, such as in the range 0,3-8°, such as in the range 0,5-7°, such as in the range 1 -5°.
- the first crystal axis may differ from the second crystal axis by a tilt angle ⁇ , where ⁇ may be within the range 0, 1 -10°, such as in the range 0,2-9°, such as in the range 0,3-8°, such as in the range 0,5-7°, such as in the range 1 -5°.
- the present invention relates to a laser comprising:
- the material or material system forming the array of quantum dots and/or quantum wires may comprise a semiconductor material, such as gallium, arsenide or indium or any combination thereof . Furthermore, the material or material system forming the array of quantum dots and/or quantum wires has a thickness smaller than 200 nm, such as smaller than 1 50 nm, such as smaller than 1 00 nm, such as smaller than 80 nm, such as smaller than 50 nm.
- the material or material system forming the array of quantum dots and/or quantum wires may be overgrown with an additional material, such as silicon or gallium arsenide.
- the pump signal may comprise electromagnetic radiation in the radio frequency, visible or near-infrared range.
- the pump signal may also comprise a direct or alternating electric current passed through the quantum dots to stimulate the emission of radiation.
- the emitted electromagnetic radiation may be in the visible or near-infrared range.
- the present invention relates to an object for calibrating an instrument, said object comprising:
- the transferring of the substantially periodic pattern to the surface may comprise removing at least part of the first or second group of crystalline elements by etching.
- the transferring of the substantially periodic pattern to the surface may comprise removing at least part of the first or second group of crystalline elements by chemical-mechanical polishing.
- the transferred substantially periodic pattern is adapted to hold an additional material, such as a metal.
- the present invention relates to an element for splitting an incoming beam into one or more outgoing beams, said element comprising:
- the incoming beam is incident on at least part of the substantially periodic pattern, said incoming beam having a first propagating direction, and wherein the one or more outgoing beams are reflected or transmitted by at least part of the substantially periodic pattern in one or more propagation directions being different from the first propagation direction.
- the present invention relates to an object for magnetically storing information, the said object comprising - an article according to the second aspect of the present invention, wherein the substantially periodic pattern is transferred to a surface of the article, said transferred substantially periodic pattern being adapted to hold a plurality of magnetic structures so as to form a plurality of magnetic domains.
- the plurality of magnetic structures may comprise iron, cobalt, chromium or any combination thereof.
- the plurality of magnetic structures are arranged according to the substantially periodic structure.
- the plurality of magnetic structures may be overgrown with a non-magnetic material.
- Fig. 1 illustrates the displacement field near the interface of two crystals bonded at their (001 ) surfaces at a twist angle ⁇ .
- A The bonding produces atomic displace- ments within a layer of characteristic thickness t.
- B Grid illustrating the modulation of the atom positions in a layer perpendicular to the interface.
- C The two atomic layers on either side of the interface, illustrating the dislocation network of period d. The model described in the following section has been used to calculate the atom positions in (B) and (C) .
- the line ss in (C) shows where the layer in (B) cuts through the interface.
- Fig. 2 The reciprocal lattice in a plane parallel to the interface. P, and P 2 are bulk Bragg (1 1 1) reflections and the cross indicate a satellite reflection.
- the solid curves are fitted Lorentzian-squared functions. A measured background intensity has been subtracted from all data points and the individual curves have been shifted vertically for clarity.
- FIG. 3 Open circles are the measured full width half maximum values w for scans along the out-of-plane direction I (a subset is shown in Fig. 2C) as a function of the twist angle ⁇ .
- the full line is calculated using the screw dislocation model described in the text.
- the inset shows the same plot on a linear scale.
- the open circles are calculated with the screw dislocation model described in the text.
- the solid lines are fitted sine functions.
- the amplitude of the sine function decays exponentially with z.
- the curves are shifted vertically for clarity.
- Periodic elastic modulation of a semiconductor crystal on the nanometer scale gives rise to novel electronic and optical properties.
- external elastic modulation of a buried quantum well can lead to the formation of quantum wires or quantum dots.
- the present invention focuses on small twist angles. It is demonstrated that the cha- racteristic thickness t of the elastic modulation, defined as the sum of the exponential decay lengths of the modulation amplitude to either side of the interface (see Fig . 1 ), is inversely proportional to the twist angle ⁇ .
- the technique used to investigate the elastic modulation near the interface is synchrotron X-ray diffraction.
- the penetration of high intensity X-rays enables the non-destructive structural investigation of buried interfaces.
- the samples were prepared by direct wafer bonding, without an intermediate adhesive or oxide layer, which is a well-established technique for a wide variety of applications in microelectronics and micromechanics.
- the wafers used were 1 0 cm diameter commercial grade mirror-polished Si(001 ), 350 ⁇ m thick, and were stripped of their native oxide in a 5 % HF solution prior to contacting in a class 1 00 clean-room.
- the contacted pairs were then annealed at 1000°C for 1 hr in a nitrogen atmosphere to achieve high-strength silicon covalent bonding at the interface.
- Samples ( " 1 cm 2 ) diced from wafer pairs that were bonded with twist angles between 0.4° and 7.5°.
- the tilt angle (miscut) of the wafers defined as the misorientation of the physical surface relative to the crystallographic [001 ] direction, was less than 0.1 °.
- one of the two bonded wafers was thinned to about 30 ⁇ m by mechanical grinding followed by chemical etching .
- the X-ray measurements were performed at the undulator beamline ID32 at the European Synchrotron Radiation Facility (ESRF) and at the wiggler beamline BW2 at HASYLAB, using six circle diffractometers.
- ESRF European Synchrotron Radiation Facility
- the wavelengths used were 0.5254 A and 1 .24 A at ID32 and HASYLAB, respectively. Must of the experiments were performed at ID32, only one sample, where one of the wafers was thinned to 1 .5 ⁇ m was measured at BW2.
- the typical beam size at sample at ID32 was 0.5mm vertical, 0.2mm horizontal.
- the samples were mounted in air with sample surface normal aligned with the ⁇ - rotation axis.
- the detector slits before the sample was typically 0.5 x 0.5 mm 2 .
- the intensities along satellite rods were measured by measuring the peak and subtracting the average background from either side of the peak. Several rods were measured using the conventional co- integration and all gave the same results as obtained when both peak signal and background
- the satellite reflections closest to the (1 1 1) reflections were scanned along the out- of-plane direction for a set of seven bonded wafer pairs with different twist angles. Four examples are shown in Fig. 2C.
- the line shape of the measured reflections is fitted with a Lorentzian-squared function: I(A,) - I ' ( 1 ⁇ F )1 (2)
- the displacement field has been simulated numerically for two simple cubic lattices, forming a square network of dislocations at their common interface.
- N d/a lattice parameters
- the elastic modulation can be made to extend many nanometers into the silicon wafers. Indeed, the modulation penetrates much further into the crystals than the characteristic thickness t, due to the long exponential tails.
- the elastically modulated region provides a regular lattice with periodicity in the range 1 - 1 0 nm, a range for metrology applications that is difficult to access with lithographic techniques. In this case, the modulated region could be exposed by etching to within a few nanometers of the interface. This modulated substrate could also be used as a template for overgrowth of periodically strained layers.
- the periodic strain field may be used as a template for a meteorological calibration standard for Scanning Tunnelling Microscopy (STM), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) in the 3-100 nm regime. Calibration standards in this regime are difficult to obtain; the lattice constant of standard crystalline materials are too small and most artificial structures have too large a lattice constant.
- a calibration standard can be accomplished by wafer bonding two Si( 1 00) wafers with zero tilt at twist angles of ⁇ , where ⁇ is in the range 0.2°-7°. This results in a periodic dislocation network with lattice spacing given by equation (1 ) .
- this periodic lattice In order to be used as a calibration standard this periodic lattice must be transferred to the surface of one of the two crystals. After bonding, one of the two crystals must be thinned down to 100 nm or less, in order to allow the periodic strain field in the direction perpendicular to the bonded interface to extend to the surface of the thinned crystal.
- the thinning can be achieved by preparing one of the wafers with an H- implanted etch stop prior to bonding, and etching with standard etchants such as KOH to remove the silicon on one side of the interface down to the etch stop.
- the strain field has an exponential decay away from the interfaces with 1 /e lengths of 1 -30 nm, so the etch stop must have a comparable depth.
- chemical-mechanical polishing techniques could be applied to thin one of the wafers.
- thin membranes could be produced in one of the wafers prior to bonding, by chemical or physical etching techniques such as reactive ion etching. Roughness of the surface defined by the etch stop due to etching can be reduced, for example, by repeated oxidation and etching in HF.
- the periodic strain field penetrates to the surface, it can be made more easily detectable, for example by overgrowth of a suitable material, such as a metal.
- a material is chosen which shows preferential growth at sites with a specific strain, leading to a replication of the periodic pattern of the strain field in the overgrown material.
- a metallic overlayer would also have advantages for STM measurements, where the substrate must be conducting.
- the pattern will have the same periodicity as the underlying grain boundary, and can be imaged with the above mentioned scanning techniques.
- the period of the pattern is given by the twist angle between the two crystals as described in equation ( 1 ), and can be measured independently and extremely accurately by, for example, X-ray techniques, in order to provide a standard reference for the scanning probe techniques.
- the twist angle can be determined with accuracy better than 0.01 °.
- a single bonded wafer could produce hundreds of identical calibration standards for distribution by manufacturers of scanning probe systems to their customers. Owing to the two dimensional nature of the periodic strain field, the calibration standards could also be used for calibrating distortions that affect the relative scales of perpendicular axes in the scanned images.
- the periodic strain field may be used as a template for growth of quantum dot lasers.
- the efficiency of such lasers depend on being able to produce a very high density of clusters of semiconductor material on a surface, the cluster size being in the nanometer range, and the clusters being nearly monodisperse.
- the optical properties of such clusters can be compared to artificial atoms with sharp absorption lines, and this has a number of advantages for laser fabrication in, for example, telecommunications applications.
- the wavelength of spontaneous emission of the dots is much more stable to temperature changes than so-called quantum wire or quantum well lasers.
- a key challenge in the fabrication of such dots by self organisation techniques has been the compromise between achieving a dense packing, and preventing clustering.
- Producing a periodic strain modulation at a free surface provides a way of controlling the cluster formation process by providing a periodic array of preferred nucleation sites as a template for overgrowth of quantum dots.
- the periodic lattice must be transferred to the surface of one of the two crystals by the method described in the previous embodiment.
- one of the two crystals must be thinned down to about 1 00 nm, in or- der to allow the strain field in the direction perpendicular to the bonded interface to extend to the surface of the thinned crystal.
- the thinning can be achieved by preparing one of the wafers with an H- implanted etch stop prior to bonding, and etching with standard etchants such as KOH to remove the silicon on one side of the interface down to the etch stop.
- the strain field has an exponential decay away from the interfaces with 1 /e lengths of 1 -30nm, so the etch stop must have a comparable depth. Roughness of the surface defined by the etch stop due to etching can be reduced, for example, by repeated oxidation and etching in HF.
- any oxide or contamination layer at this surface can be removed in vacuum by standard techniques such as high- temperature annealing and sputtering.
- deposition of semiconductor materials suitable for quantum dots such as Indium Arsenide can be carried out, in a molecular beam epitaxy system or chemical vapour deposition system.
- the clusters will grow preferentially at specific sites on the strained surface, which minimise the strain energy between the overgrown quantum dots and the substrate. In this way, a periodic pattern of quantum dots can be made.
- the spacing of the quantum dots can be controlled, to achieve optimum density for a given mean quantum dot size.
- the electronic state of the quantum dots can be controlled.
- a protective cap layer of semiconductor material can be deposited on the quantum dots to protect them from oxidation.
- Further electrical connections to provide injection of carriers can be fabricated by prior art methods. Injection of charge carriers is necessary to stimulate lasing.
- the periodic strain field may be used as a modulator of a buried quantum well layer, in order to form a quantum dot laser (described above). In this embodiment, it is not necessary to thin one of the wafers very accurately.
- a quantum well structure is fabricated in one of the wafers, with a suitable thin protective layer.
- a quantum well structure consists of a nanometer-thickness layer of one type of semiconductor grown epitaxially on another, for example gallium indium arsenide on gallium arsenide, using standard techniques such as molecular beam epitaxy
- the thickness of the thin protective layer is 1 00nm or less, such that the periodic strain field generated at the interface between the two wafers can penetrate through the protective layer and modulate the quantum well. This strain modulation will have the effect of modulating the electronic band-structure of the charge carriers in the, creating periodic electronic structure analogous to an array of quantum dots
- the periodic strain field may be used as a template for growth of arrays of periodic magnetic nanostructures, for applications such as data storage.
- An important challenge in data storage materials is the fabrication of regular magnetic nanodomains that can be addressed individually. Self-organisation techniques for achieving this depend on a compromise between achieving a dense packing, and preventing clustering.
- Producing a periodic strain modulation at a free surface provides a way of controlling the cluster formation process by providing a periodic array of preferred nucleation sites as a template for overgrowth of magnetic nanostructures.
- the periodic lattice must be transferred to the surface of one of the two crystals by the method described in the first embodiment. Again, after bonding, one of the two crystals must be thinned down to about 1 00 nm, in order to allow the strain field in the direction perpendicular to the bonded interface to extend to the surface of the thinned crystal.
- the thinning can be achieved by preparing one of the wafers with an H- implanted etch stop prior to bonding, and etching with standard etchants such as KOH to remove the silicon on one side of the interface down to the etch stop.
- standard etchants such as KOH
- the strain field has an exponential decay away from the interfaces with 1 /e lengths of 1 -30nm, so the etch stop must have a comparable depth.
- Roughness of the surface defined by the etch stop due to etching can be reduced, for example, by repeated oxidation and etching in HF.
- any oxide or contamination layer at this surface can be removed in vacuum by standard techniques such as high- temperature annealing and sputtering.
- magnetic materials are deposited suitable for data storage, such as iron, cobalt, chromium, and alloys of such materials, using techniques such as molecular beam epitaxy system or chemical vapour deposition system.
- the clusters will grow preferentially at specific sites on the strained surface, which minimise the strain energy between the overgrown magnetic nanostructures and the substrate.
- a buffer layer of one metallic material may be deposited prior to the active magnetic material, in order to optimise diffusion of the magnetic material. In this way, a periodic magnetic pattern can be made.
- the spacing of the quantum dots can be controlled, to achieve optimum density for a given mean quantum dot size.
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Abstract
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Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP00940221A EP1196350A2 (en) | 1999-06-28 | 2000-06-28 | Nanometer-scale modulation |
AU55223/00A AU5522300A (en) | 1999-06-28 | 2000-06-28 | Nanometer-scale modulation |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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DKPA199900918 | 1999-06-28 | ||
DKPA199900918 | 1999-06-28 |
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WO2001000522A2 true WO2001000522A2 (en) | 2001-01-04 |
WO2001000522A3 WO2001000522A3 (en) | 2001-05-03 |
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PCT/DK2000/000348 WO2001000522A2 (en) | 1999-06-28 | 2000-06-28 | Nanometer-scale modulation |
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EP (1) | EP1196350A2 (en) |
AU (1) | AU5522300A (en) |
WO (1) | WO2001000522A2 (en) |
Cited By (8)
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US6329070B1 (en) * | 1999-12-09 | 2001-12-11 | Cornell Research Foundation, Inc. | Fabrication of periodic surface structures with nanometer-scale spacings |
DE10108853A1 (en) * | 2001-02-18 | 2002-09-05 | Hahn Meitner Inst Berlin Gmbh | Production of regular arrangement of nanocrystalline magnetic particles comprises stabilizing magnetic particles in colloidal solution, wetting substrate with solution at specified angle, and depositing particles |
FR2826378A1 (en) * | 2001-06-22 | 2002-12-27 | Commissariat Energie Atomique | COMPOSITE STRUCTURE WITH UNIFORM CRYSTALLINE ORIENTATION AND METHOD FOR CONTROLLING THE CRYSTALLINE ORIENTATION OF SUCH A STRUCTURE |
WO2006007396A1 (en) * | 2004-06-16 | 2006-01-19 | Massachusetts Institute Of Technology | Strained silicon-on-silicon by wafer bonding and layer transfer |
FR2877662A1 (en) * | 2004-11-09 | 2006-05-12 | Commissariat Energie Atomique | PARTICLE NETWORK AND METHOD FOR MAKING SUCH A NETWORK |
US7535089B2 (en) | 2005-11-01 | 2009-05-19 | Massachusetts Institute Of Technology | Monolithically integrated light emitting devices |
USRE40725E1 (en) * | 1999-12-09 | 2009-06-09 | Nippon Telegraph And Telephone Corporation | Magnetic body formed by quantum dot array using non-magnetic semiconductor |
US8063397B2 (en) | 2006-06-28 | 2011-11-22 | Massachusetts Institute Of Technology | Semiconductor light-emitting structure and graded-composition substrate providing yellow-green light emission |
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- 2000-06-28 AU AU55223/00A patent/AU5522300A/en not_active Abandoned
- 2000-06-28 WO PCT/DK2000/000348 patent/WO2001000522A2/en not_active Application Discontinuation
- 2000-06-28 EP EP00940221A patent/EP1196350A2/en not_active Withdrawn
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Publication number | Priority date | Publication date | Assignee | Title |
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EP1165864A1 (en) * | 1999-12-09 | 2002-01-02 | Cornell Research Foundation, Inc. | Fabrication of periodic surface structures with nanometer-scale spacings |
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USRE40725E1 (en) * | 1999-12-09 | 2009-06-09 | Nippon Telegraph And Telephone Corporation | Magnetic body formed by quantum dot array using non-magnetic semiconductor |
US6329070B1 (en) * | 1999-12-09 | 2001-12-11 | Cornell Research Foundation, Inc. | Fabrication of periodic surface structures with nanometer-scale spacings |
DE10108853A1 (en) * | 2001-02-18 | 2002-09-05 | Hahn Meitner Inst Berlin Gmbh | Production of regular arrangement of nanocrystalline magnetic particles comprises stabilizing magnetic particles in colloidal solution, wetting substrate with solution at specified angle, and depositing particles |
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JP2008520444A (en) * | 2004-11-09 | 2008-06-19 | コミサリヤ・ア・レネルジ・アトミク | Particle networks and methods for realizing such networks |
WO2006051186A3 (en) * | 2004-11-09 | 2006-12-14 | Commissariat Energie Atomique | Particle network and method for realizing such a network |
FR2877662A1 (en) * | 2004-11-09 | 2006-05-12 | Commissariat Energie Atomique | PARTICLE NETWORK AND METHOD FOR MAKING SUCH A NETWORK |
US7985469B2 (en) | 2004-11-09 | 2011-07-26 | Commissariat A L'energie Atomique | Particle network comprising particles disposed on a substrate and method for realizing such a network |
US7535089B2 (en) | 2005-11-01 | 2009-05-19 | Massachusetts Institute Of Technology | Monolithically integrated light emitting devices |
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US8012592B2 (en) | 2005-11-01 | 2011-09-06 | Massachuesetts Institute Of Technology | Monolithically integrated semiconductor materials and devices |
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US8063397B2 (en) | 2006-06-28 | 2011-11-22 | Massachusetts Institute Of Technology | Semiconductor light-emitting structure and graded-composition substrate providing yellow-green light emission |
Also Published As
Publication number | Publication date |
---|---|
WO2001000522A3 (en) | 2001-05-03 |
AU5522300A (en) | 2001-01-31 |
EP1196350A2 (en) | 2002-04-17 |
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