Abstract: Silicon wafers having excellent voltage resistance characteristics of an oxide film and high C-mode characteristics are derived from single crystal silicon ingots doped with nitrogen and hydrogen, characterized in that a plurality of voids constituting a bubble-like void aggregates are present ?50% relative to total voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 is ?20% of the total area of wafer; a V2 region having a void density of 5×102 to 2×104/cm3 occupies ?80% of the total area of the wafer; and bulk microdefect density is ?5×108/cm3.
Abstract: Silicon wafers doped with nitrogen, hydrogen and carbon, have a plurality of voids, wherein 50% or more of the total number of voids are bubble-like shaped aggregates of voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 which occupies 20% or less of the total area of the silicon wafer; a V2 region having a void density of 5×102 to 2×104/cm3 which occupies 80% or more of the total area of said silicon wafer; and a bulk micro defect density which is 5×108/cm3 or more, have excellent GOI characteristics and a high C-mode pass rate. The wafers are cut from a single crystal pulled by a method in which carbon, nitrogen, and hydrogen dopants are controlled, and the crystal is subjected to rapid cooling.
Abstract: A dichalcogenide thermoelectric material having a very low thermal conductivity in comparison with a conventional metal or semiconductor is described. The dichalcogenide thermoelectric material has a structure of Formula 1 below: RX2-aYa??Formula 1 wherein R is a rare earth or transition metal magnetic element, X and Y are each independently an element selected from the group consisting of S, Se, Te, P, As, Sb, Bi, C, Si, Ge, Sn, B, Al, Ga, In, and a combination thereof, and 0?a<2.
Abstract: A silicon single crystal pull-up apparatus is used to pull up a doped silicon single crystal from a melt by means of the Czochralski process and includes a pull-up furnace, a sample chamber which is externally mounted on the pull-up furnace and houses a sublimable dopant, a shielding means for thermally isolating the interior of the pull-up furnace and the interior of the sample chamber, a sample tube which can be raised and lowered between the interior of the sample chamber and the interior of the pull-up furnace, and a raising and lowering means which is provided with guide rails on which the sample tube can slide and a wire mechanism by which the sample tube is raised and lowered along the guide rails.
Abstract: A method of producing a crystalline semiconductor material includes feeding particles of the semiconductor material and/or a precursor compound of the semiconductor material into a gas flow, wherein the gas flow has a sufficiently high temperature to convert the particles of the semiconductor material from a solid into a liquid and/or gaseous state and/or to thermally decompose the precursor compound, condensing out and/or separating the liquid semiconductor material from the gas flow, and converting the liquid semiconductor material to a solid state with formation of mono- or polycrystalline crystal properties.
Type:
Application
Filed:
April 11, 2011
Publication date:
August 15, 2013
Applicant:
SCHMID SILICON TECHNOLOGY GMBH
Inventors:
Uwe Kerat, Christian Schmid, Jochem Hahn
Abstract: The invention relates to a method of fabricating at least one polycrystalline silicon plate (68, 70) with one (64, 66) of its two faces presenting predetermined relief, in which method a layer of polycrystalline silicon (60, 62) is deposited on at least one (56, 58) of the two faces of a support (50). The method comprises the steps of embossing said face (52, 54) of the support (50) to impart thereto a shape that is complementary to said relief; depositing said polycrystalline silicon layer (60, 62) on said embossed face (56, 58) of the support (50), the surface (64 or 66) of said polycrystalline silicon layer situated in contact with said embossed face (56 or 58) then taking on the shape of said relief; and eliminating said support in order to obtain said polycrystalline silicon plate (68 or 70). The invention is applicable to fabricating solar cells.
Abstract: A silica glass crucible for pulling up a silicon single crystal including a wall part and a bottom part is provided with a natural silica glass layer which forms at least one part of a an inner surface of the bottom part, and a synthetic silica glass layer which forms at least an inner surface of the wall part, wherein a concentration of Ca included in the natural silica glass layer is 0.5 ppm or less.
Abstract: An object of the present invention is to effectively add Ge in the production of GaN through the Na flux method. In a crucible, a seed crystal substrate is placed such that one end of the substrate remains on the support base, whereby the seed crystal substrate remains tilted with respect to the bottom surface of the crucible, and gallium solid and germanium solid are placed in the space between the seed crystal substrate and the bottom surface of the crucible. Then, sodium solid is placed on the seed crystal substrate. Through employment of this arrangement, when a GaN crystal is grown on the seed crystal substrate through the Na flux method, germanium is dissolved in molten gallium before formation of a sodium-germanium alloy. Thus, the GaN crystal can be effectively doped with Ge.
Type:
Grant
Filed:
March 26, 2010
Date of Patent:
August 6, 2013
Assignees:
Toyoda Gosei Co., Ltd., NGK Insulators, Ltd., Osaka University
Abstract: During a CZ or similar process, a silica crucible is held in a graphite or similar susceptor while being heated to above between about 1580 and 1620 degrees C. Vents or grooves formed in at least one of the outer surface of the crucible and the inner surface of the susceptor permit gasses to vent upwardly and out from between the crucible and susceptor. This permits gas evolved from the crucible as a result of the heat to be vented rather than expanding between the crucible and susceptor thereby deforming the crucible.
Type:
Grant
Filed:
September 2, 2009
Date of Patent:
July 30, 2013
Assignee:
Heraeus Shin-Etsu America, Inc.
Inventors:
Katsuhiko Kemmochi, Robert Joseph Coolich, Michael Randall Fallows
Abstract: Described herein is a method for producing a quartz glass crucible, including the steps of: preparing a crucible base material that is made of quartz glass and has a crucible shape; producing a synthetic quartz glass material by the direct process or the soot process; processing the synthetic quartz glass material into a crucible shape without pulverizing the synthetic quartz glass material; and welding the synthetic quartz glass material processed into the crucible shape to the inner surface of the crucible base material. As a result, there are provided a quartz glass crucible that avoids generation of dislocation in a silicon single crystal, the generation of dislocation caused by the crucible itself, at the time of production of a silicon single crystal and has high heat resistance, a method for producing the quartz glass crucible, and a method for producing a silicon single crystal, the method using such a quartz glass crucible.
Abstract: The invention describes a process for removing nonmetallic impurities from metallurgical silicon. A melt is produced from metallurgical silicon and halide-containing silicon. As a result, the impurities are sublimed out and removed from the melt in the form of nonmetal halides. Compared with the known process, in which gaseous halogen is blown through an Si melt, the novel process can be carried out in a particularly simple and efficient manner.
Type:
Application
Filed:
July 29, 2009
Publication date:
July 4, 2013
Inventors:
Seyed-Javad Mohsseni-Ala, Christian Bauch, Rumen Deltschew, Thoralf Gebel, Gerd Lippold, Matthias Heuer, Fritz Kirscht, Kamel Ounadjela
Abstract: When a silicon single crystal is grown by the CZ method using a pulling apparatus in which a voltage can be applied between a crystal suspending member and a crucible, the voltage is applied under the condition that the crystal suspending member is set as a negative electrode while the crucible is set as a positive electrode in a process for growing a lower end portion of a cylindrical portion or a tail portion which is of a non-convertible portion of the silicon single crystal. A sample wafer is collected from the lower end portion of the cylindrical portion or the tail portion, which is grown in association with the voltage application, and the metal contamination of the sample wafer is evaluated. The sample wafer has enough metal impurity concentration to evaluate the metal contamination.
Abstract: Silicon single crystals are grown from the melt by providing the melt in a crucible; imposing a horizontal magnetic field on the melt; directing a gas between the single crystal and a heat shield to a melt free surface, and controlling the gas to flow over a region of the melt free surface extending in a direction substantially perpendicular to the magnetic induction. A suitable apparatus has a crucible for holding the melt; a heat shield surrounding the silicon single crystal having a lower end which is connected to a bottom cover facing a melt free surface and a non-axisymmetric shape with respect to a crucible axis, such that gas which is directed between the crystal and the heat shield to the melt free surface is forced to flow over a region of the melt which extends substantially perpendicular to the magnetic induction.
Abstract: A silicon wafer is produced through the steps of forming a silicon ingot by a CZ method with an interstitial oxygen concentration of not more than 7.0×1017 atoms/cm3 and with a diameter of a COP occurring region not more than a diameter of a crystal, slicing a wafer from the silicon ingot after doping the silicon ingot with phosphorus, forming a polysilicon layer or a strained layer on one main surface of the wafer, and mirror polishing the other main surface of the wafer.
Abstract: An improved system based on the Czochralski process for continuous growth of a single crystal ingot comprises a low aspect ratio, large diameter, and substantially flat crucible, including an optional weir surrounding the crystal. The low aspect ratio crucible substantially eliminates convection currents and reduces oxygen content in a finished single crystal silicon ingot. A separate level controlled silicon pre-melting chamber provides a continuous source of molten silicon to the growth crucible advantageously eliminating the need for vertical travel and a crucible raising system during the crystal pulling process. A plurality of heaters beneath the crucible establish corresponding thermal zones across the melt. Thermal output of the heaters is individually controlled for providing an optimal thermal distribution across the melt and at the crystal/melt interface for improved crystal growth. Multiple crystal pulling chambers are provided for continuous processing and high throughput.
Abstract: The present invention is a semiconductor single crystal manufacturing apparatus including, within a growth furnace main body, a crucible, and a heater disposed around the crucible, wherein a heat insulating cylinder is disposed around the heater within the growth furnace main body, the heat insulating cylinder includes a step portion dividing the heat insulating cylinder into the upper part and the lower part at the inside surface thereof, the inner diameter of the lower part is larger than the inner diameter of the upper part, a heat insulating plate is disposed below the heater and on the inside of the lower part of the heat insulating cylinder within the growth furnace main body, and the diameter of the heat insulating plate is larger than the inner diameter of the upper part of the heat insulating cylinder and is smaller than the inner diameter of the lower part.
Abstract: Methods for producing crucibles for holding molten material that contain a reduced amount of gas pockets are disclosed. The methods may involve use of molten silica that may be outgassed prior to or during formation of the crucible. Crucibles produced from such methods and ingots and wafers that are produced from crucibles with a reduced amount of gas pockets are also disclosed.
Type:
Application
Filed:
November 18, 2011
Publication date:
May 23, 2013
Applicant:
MEMC ELECTRONIC MATERIALS, INC.
Inventors:
Steven L. Kimbel, Harold W. Korb, Richard J. Phillips, Shailendra B. Rathod
Abstract: Computer controlled quality control methods for manufacturing high purity polycrystalline granules are introduced. Polycrystalline silicon granules are sampled and converted into single crystal specimen in computer controlled system, eliminating the need of human operator in controlling the processing parameters. Single crystal silicon test samples, then characterized by FTIR and other standard analysis, are therefore more representative of the starting granular silicon.
Type:
Application
Filed:
August 31, 2012
Publication date:
May 9, 2013
Applicant:
GIGA INDUSTRIES, INC.
Inventors:
David C. Spencer, Jimmie D. Walter, Friedrich H. Doerbeck
Abstract: A method of manufacturing a down-conversion substrate for use in a light system includes forming a first crystallography layer including one or more phosphor materials and, optionally, applying at least one activator to the crystallography layer, heating the crystallography layer at high temperature to promote crystal growth in the crystallography layer, and drawing out the crystallography layer and allowing the crystallography layer to cool to form the down-conversion substrate. A light system includes an excitation source for emitting short wavelength primary emissions; and a down-conversion substrate disposed in the path of at least some of the primary emissions from the excitation source to convert at least a portion of the primary emissions into longer-wavelength secondary emissions, wherein the substrate includes one or more crystallography layers, wherein each crystallography layer includes one or more phosphor materials, and optionally at least one activator.
Abstract: In this method for manufacturing a silicon single crystal, when growing the silicon single crystal, in order to control the V/G value with high accuracy so as to yield a desired defect-free region, it is important to conduct the pulling at a constant pulling rate. In the method for pulling a silicon single crystal in the present invention, in order to control the V/G value with high accuracy, the distance ?t between the melt surface of the silicon melt and the heat shielding member that is disposed so as to oppose to and to partially cover this melt surface is continuously measured while pulling (growing) the silicon single crystal.
Abstract: A velocity of Ar gas flow passing through between a lower end of a cylindrical body and a thermal shielding body is influenced by arrangement of a pulling path of single crystal silicon, a cylindrical body, and a thermal shielding body. Accordingly, the velocity of the Ar gas flow passing through between a lower end of the cylindrical body and the thermal shielding body is controlled by adjusting a relative position of the pulling path of the single crystal silicon, the cylindrical body, and the thermal shielding body. As described above, dust falling off to silicon melt can be reduced, thereby preventing deterioration in quality of the single crystal silicon.
Abstract: A method for growing II-VI semiconductor crystals and II-VI semiconductor layers as well as crystals and layers of their ternary or quaternary compounds from the liquid or gas phase is proposed. To this end, the solid starting materials are introduced into a growing chamber for the growing of crystals. Inside the growing chamber, carbon monoxide is supplied by way of reducing agent. At least certain zones of the growing chamber are heated to a temperature at which a first-order phase transition of the starting materials takes place and the starting materials pass into the liquid or gas phase. The starting materials are then cooled down accompanied by the formation of a semiconductor crystal or semiconductor layer, again with a first-order phase transition taking place. The oxygen present in the growing chamber is bound by the carbon monoxide and the formation of an oxide layer at the phase boundary of the growing semiconductor crystal or semiconductor layer is prevented.
Abstract: A system for growing silicon crystals that facilitates controlling a shape of a melt-solid interface is described. The crystal growing system includes a heated crucible including a semiconductor melt from which a monocrystalline ingot is grown according to a Czochralski process. The ingot is grown on a seed crystal pulled from the melt. The method includes applying an unbalanced cusped magnetic field to the melt, and rotating the ingot and the crucible in the same direction while the ingot is being pulled from the melt.
Type:
Grant
Filed:
June 29, 2009
Date of Patent:
March 19, 2013
Assignee:
MEMC Electronic Materials, Inc.
Inventors:
Hariprasad Sreedharamurthy, Milind Kulkarni, Richard G. Schrenker, Joseph C. Holzer, Harold W. Korb
Abstract: Semiconductor wafers composed of monocrystalline silicon and doped with nitrogen contain an OSF region and a Pv region, wherein the OSF region extends from the center radially toward the edge of the wafer as far as the Pv region; the wafer has an OSF density of less than 10 cm?2, a BMD density in the bulk of at least 3.5×108 cm?3, and a radial distribution of the BMD density with a fluctuation range BMDmax/BMDmin of not more than 3. The wafers are produced by controlling initial nitrogen content and maintaining oxygen within a narrow window, followed by a heat treatment.
Type:
Grant
Filed:
August 27, 2009
Date of Patent:
March 19, 2013
Assignee:
Siltronic AG
Inventors:
Timo Mueller, Gudrun Kissinger, Walter Heuwieser, Martin Weber
Abstract: Brittle polysilicon rods having a rod cross-section of 80-99% available for electrical conduction and a flexural strength of 0.1 to 80 N/mm2 are produced by a process wherein the temperature of the bridge of polysilicon rods in the Siemens process is held at a high temperature and the flow rate of chlorosilanes is increased to the maximum within a short time. The rods are easily fragmented with low force, resulting in polysilicon with a low level of metallic impurities.
Abstract: A method of making LSO scintillators with high light yield and short decay times is disclosed. In one arrangement, the method includes codoping LSO with cerium and another dopant from the IIA or IIB group of the periodic table of elements. The doping levels are chosen to tune the decay time of scintillation pulse within a broader range (between about ˜30 ns up to about ˜50 ns) than reported in the literature, with improved light yield and uniformity. In another arrangement, relative concentrations of dopants are chosen to achieve the desired light yield and decay time while ensuring crystal growth stability.
Type:
Grant
Filed:
January 27, 2012
Date of Patent:
March 12, 2013
Assignee:
Siemens Medical Solutions USA, Inc.
Inventors:
Mark S. Andreaco, Piotr Szupryczynski, A. Andrew Carey
Abstract: A silica glass crucible for pulling up a silicon single crystal including a wall part, a corner part and a bottom part is provided with an outer layer formed from an opaque silica glass layer which includes many bubbles, and an inner layer formed from a transparent silica glass layer which substantially does not include bubbles, wherein at least one part of an inner surface of the wall part and the corner part being an uneven surface formed with multiple damaged parts having a depth of 50 ?m or more and 450 ?m or less, and wherein a region among the inner surface of the bottom part within a certain range from the center of the bottom part being a smooth surface which does is substantially not formed with damage.
Type:
Grant
Filed:
November 27, 2009
Date of Patent:
March 12, 2013
Assignee:
Japan Super Quartz Corporation
Inventors:
Masaki Morikawa, Jun Furukawa, Satoshi Kudo
Abstract: A method for measuring a distance between a lower end surface of a heat shielding member including a criterion reflector inside a concavity on the lower end surface and a surface of a raw material melt includes: a silicon single crystal is pulled by the Czochralski method while a magnetic field is applied to the raw material melt in a crucible, measuring the distance between the lower end surface of the heat shielding member and the surface of the raw material melt and observing a position of a mirror image of the criterion reflector with a fixed point observation apparatus; and measuring a movement distance of the mirror image with the apparatus and calculating the distance between the lower end surface of the heat shielding member and the surface of the raw material melt from the movement distance of the image and the measured distance.
Abstract: A method for producing a mono-crystalline sheet includes providing at least two aperture elements forming a gap in between; providing a molten alloy including silicon in the gap; providing a gaseous precursor medium comprising silicon in the vicinity of the molten alloy; providing a silicon nucleation crystal in the vicinity of the molten alloy; and bringing in contact said silicon nucleation crystal and the molten alloy. A device for producing a mono-crystalline sheet includes at least two aperture elements at a predetermined distance from each other, thereby forming a gap, and being adapted to be heated for holding a molten alloy including silicon by surface tension in the gap between the aperture elements; a precursor gas supply supplies a gaseous precursor medium comprising silicon in the vicinity of the molten alloy; and a positioning device for holding and moving a nucleation crystal in the vicinity of the molten alloy.
Type:
Application
Filed:
May 23, 2011
Publication date:
March 7, 2013
Applicant:
INTERNATIONAL BUSINESS MACHINES CORPORATION
Inventors:
Mikael T. Bjoerk, Heike E. Riel, Heinz Schmid
Abstract: Silicon wafers wherein slip dislocations and warpages during device production are suppressed, contain BMDs with an octahedral shape, and of BMDs at a depth greater than 50 ?m from the surface of the wafer, the density of BMDs with diagonal size of 10 nm to 50 nm is ?1×1012/cm3, and the density of BSFs is ?1×108/cm3. The present silicon wafers preferably have an interstitial oxygen concentration of 4×1017 atoms/cm3 to 6×1017 atoms/cm3, and a density of BMDs with diagonal size of ?200 nm of not more than 1×107/cm3.
Abstract: An oxide single crystal having a composition represented by RExSi6O1.5x+12 (RE: La, Ce, Pr, Nd, or Sm, x: 8 to 10) is grown by using the Czochralski method such that the crystal growth orientation coincides with the c-axis direction. The solidification rate (the weight of the grown crystal÷the weight of the charged raw material) in the crystal growth is less than 45%.
Abstract: In the production of GaN through the flux method, deposition of miscellaneous crystals on the nitrogen-face of a GaN self-standing substrate and waste of raw materials are prevented. Four arrangements of crucibles and a GaN self-standing substrate are exemplified. In FIG. 1A, a nitrogen-face of a self-standing substrate comes into close contact with a sloped flat inner wall of a crucible. In FIG. 1B, a nitrogen-face of a self-standing substrate comes into close contact with a horizontally facing flat inner wall of a crucible, and the substrate is fixed by means of a jig. In FIG. 1C, a jig is provided on a flat bottom of a crucible, and two GaN self-standing substrates are fixed by means of the jig so that the nitrogen-faces of the substrates come into close contact with each other. In FIG. 1D, a jig is provided on a flat bottom of a crucible, and a GaN self-standing substrate is fixed on the jig so that the nitrogen-face of the substrate is covered with the jig.
Abstract: Provided is a method for reliably and easily measuring a liquid level by selecting an optimal reflection method from among a plurality of reflection methods, depending on growing conditions of a pulled single crystal. The method comprises: setting a plurality of measuring methods having different ways of determining the liquid level; creating, in advance, information that associates with a gap between the outer peripheral face of the single crystal and a predetermined position located between a heat shield and the outer peripheral face of the single crystal; determining the gap in accordance with manufacturing conditions; selecting a measuring method associated to the determined gap, on the basis of the information; and measuring the liquid level of a melt surface in use of the selected measuring method.
Abstract: A method for detecting a diameter of a single crystal at the time of pulling the single crystal from a silicon melt contained in a crucible according to the Czochralski method, the method including at least: using two cameras placed equidistant from each other as a target diameter upon forming a straight-body portion of the single crystal and face both ends of the diameter of the single crystal in a growth point of the single crystal respectively, to separately capture both of the ends of the growth point of the single crystal from an outside of a furnace, the growth point being a contact point between the single crystal and a melt surface; and detecting the diameter of the single crystal on the basis of the captured images. As a result, diameter detection precision is improved.
Abstract: The present invention resides in a silicon single crystal growth method of pulling up and growing a single crystal from a melt of a silicon raw material in a quartz crucible based on a Czochralski method, wherein the method comprises the steps of: applying a DC voltage between an outer wall of the quartz crucible acts as a positive electrode and a pulling wire or pulling shaft for pulling up the silicon single crystal acts as a negative electrode; and fixing an electric current flowing through the silicon single crystal over a period of time for pulling up the single crystal, to grow the single crystal; as well as a pulling apparatus therefor.
Type:
Grant
Filed:
February 28, 2008
Date of Patent:
January 1, 2013
Assignee:
Shin-Etsu Handotai Co., Ltd.
Inventors:
Yuuichi Miyahara, Atsushi Iwasaki, Tetsuhiro Oda
Abstract: A method of making a single-crystalline Si wafer with an approximately polygonal cross section and having a material property that is the same as a zone-pulled Si crystal, and the single-crystalline Si wafer. The method includes pulling at least one bottle neck of a crystal vertically downwards from a rotating hanging melt drop. The rotational speed of the crystal is reduced to between 0 and less than 1 rpm. In a crystal-growth phase, a Si single crystal ingot is pulled vertically downwards with an approximately polygonal cross section. An inductor is used to generate a temperature profile at a growth phase boundary of the crystal that corresponds to the shape of a cross section of the pulled Si single crystal ingot. The growth is ended at a desired pulling length and the Si single crystal ingot is cut into wafers having an approximately polygonal cross section.
Type:
Grant
Filed:
April 4, 2006
Date of Patent:
December 25, 2012
Assignee:
PV Silicon Forschungs und Produktions GmbH
Inventors:
Nikolai Abrosimov, Anke Luedge, Andris Muiznieks, Helge Riemann
Abstract: A single-crystal manufacturing apparatus comprises a chamber, a crucible in the chamber, a heater arranged around the crucible, a lifting mechanism for lifting a seed crystal, and a guide passage for the seed crystal and a grown single crystal. In the single-crystal manufacturing apparatus, a material polycrystal contained the crucible is melted by a heater, and the seed crystal is made to contact the molten polycrystal and is lifted. The single-crystal manufacturing apparatus comprises a cylindrical quartz tube having a curved bottom portion, and a dome-shaped quartz plate. The curved bottom portion faces the crucible from the upper portion of the chamber through the guide passage. The quartz plate is arranged to enclose the quartz tube. The quartz tube has a reflecting structure for reflecting a heat ray from at least its bottom portion whereas the quartz plate has a reflecting structure for reflecting the heat ray to the crucible.
Abstract: Provided is an apparatus capable of producing a fluoride crystal in a very short period of time, and a method suitable for producing a fluoride crystal using the apparatus. The apparatus comprises a chamber, a window material, and the like, and is modified such that it can evacuate air from the chamber to provide a high degree vacuum there. The apparatus further includes a crucible, which has a perforation at its bottom. The capillary portion of the perforation is adjusted to facilitate the contact of a seed crystal with a melt. By using the apparatus it is possible to stably produce high quality single crystals of fluorides in a short period of time.
Abstract: A seed crystal axis used in a solution growth of single crystal production system is provided to prevent formation of polycrystals and grow a single crystal with a high growth rate. The seed crystal axis includes a seed crystal bonded to a seed crystal support member between which is interposed a laminated carbon sheet having a high thermal conductivity in a direction perpendicular to a solution surface of a solvent. The laminated carbon sheet includes a plurality of carbon thin films laminated with an adhesive or a plurality of pieces with differing lamination directions arranged in a lattice. Alternatively, a wound carbon sheet including a carbon strip wound concentrically from the center or a wound carbon sheet including a plurality of carbon strips with differing thicknesses which are wound and laminated from the center may be provided.
Abstract: An SOI wafer is constructed from a carrier wafer and a monocrystalline silicon layer having a thickness of less than 500 nm, an excess of interstitial silicon atoms prevailing in the entire volume of the silicon layer. The SOI wafers may be prepared by Czochralski silicon single crystal growth, the condition v/G<(v/G)crit=1.3×10?3 cm2/(K·min) being fulfilled at the crystallization front over the entire crystal cross section, with the result that an excess of interstitial silicon atoms prevails in the silicon single crystal produced; separation of at least one donor wafer from this silicon single crystal, bonding of the donor wafer to a carrier wafer, and reduction of the thickness of the donor wafer, with the result that a silicon layer having a thickness of less than 500 nm bonded to the carrier wafer remains.
Type:
Grant
Filed:
January 18, 2008
Date of Patent:
December 4, 2012
Assignee:
Siltronic AG
Inventors:
Dieter Graef, Markus Blietz, Reinhold Wahlich, Alfred Miller, Dirk Zemke
Abstract: A method for producing a single crystal of semiconductor material having material properties of a zone-pulled single crystal includes providing a vessel transmissive to high frequency magnetic fields and having a granulate of a granular semiconductor material disposed therein and a first conductor disposed externally thereto. A high frequency current is supplied to a planar inductor disposed above the vessel, the planar inductor having a turn and a slit as a current supply so as to produce an open melt lake on the granulate by a temperature field at a surface of the granulate produced by thermal power of the planar inductor and a heating action of the first inductor, the melt lake being embedded in unmelted material of the granular semiconductor material and not being in contact with a wall of the vessel. A single crystal is pulled form the melt lake of the semiconductor material upwards.
Type:
Application
Filed:
November 23, 2010
Publication date:
November 15, 2012
Applicant:
FORSCHUNGSVERBUND BERLIN E.V.
Inventors:
Helge Riemann, Nikolai V. Abrosimov, Joerg Fischer, Matthias Renner
Abstract: The present invention is a single-crystal manufacturing method based on the Czochralski method, comprising at least the steps of: producing a melt by heating and melting a crystalline raw material in a crucible with a heater; maturing the melt by keeping the melt at a high temperature; growing a single crystal after dipping a seed crystal into the matured melt, wherein the heater and the crucible are relatively moved up and down in the step of maturing. As a result, there is provided a single-crystal manufacturing method that enables the generation of dislocation to be effectively suppressed and a high quality single crystal to be manufactured at good yield, particularly in case of pulling the single crystal having a large diameter, in manufacture of the single crystal.
Abstract: Provided are a resistance heated sapphire single crystal ingot grower, a method of manufacturing a resistance heated sapphire single crystal ingot, a sapphire single crystal ingot, and a sapphire wafer. The resistance heated sapphire single crystal ingot grower comprises according to an embodiment includes a chamber, a crucible included in the chamber and containing an alumina melt, and a resistance heating heater included inside the chamber and heating the crucible.
Type:
Application
Filed:
January 19, 2012
Publication date:
November 8, 2012
Inventors:
Do Won SONG, Young Hee Mun, Sang Hoon Lee, Seong Oh Jeong, Chang Youn Lee
Abstract: A protective coating is prepared for, and applied to, crucibles used in the handling of molten materials that are solidified in the crucible and then removed as ingots. Crucibles containing this protective coating may be used for the solidification of silicon. The coating has a specified oxygen content and contains a mineral binder and silicon nitride or silicon oxynitride.
Abstract: A pressure differential is applied across a mold sheet and a semiconductor (e.g. silicon) wafer (e.g. for solar cell) is formed thereon. Relaxation of the pressure differential allows release of the wafer. The mold sheet may be cooler than the melt. Heat is extracted almost exclusively through the thickness of the forming wafer. The liquid and solid interface is substantially parallel to the mold sheet. The temperature of the solidifying body is substantially uniform across its width, resulting in low stresses and dislocation density and higher crystallographic quality. The mold sheet must allow flow of gas through it. The melt can be introduced to the sheet by: full area contact with the top of a melt; traversing a partial area contact of melt with the mold sheet, whether horizontal or vertical, or in between; and by dipping the mold into a melt. The grain size can be controlled by many means.
Type:
Grant
Filed:
November 17, 2011
Date of Patent:
October 23, 2012
Assignee:
1366 Technologies Inc.
Inventors:
Emanuel M. Sachs, Richard L. Wallace, Eerik T. Hantsoo, Adam M. Lorenz, G. D. Stephen Hudelson, Ralf Jonczyk
Abstract: A ribbon crystal pulling furnace has a base insulation and a liner insulation removably connected to the base insulation. At least a portion of the liner insulation forms an interior for containing a crucible.
Type:
Grant
Filed:
June 13, 2008
Date of Patent:
October 23, 2012
Assignee:
Max Era, Inc.
Inventors:
Richard Wallace, David Harvey, Weidong Huang, Scott Reitsma, Christine Richardson
Abstract: The present invention relates to a large-sized and high-quality bismuth-zinc-borate (Bi.sub.2 ZnB.sub.2 O.sub.7) single crystal, preparation methods and applications thereof. The crystal has cross-sectional dimensions greater than one centimeter, a nonlinear optical effect of about 3-4 times that of KH.sub.2 PO.sub.4 (KDP), and an optical transmission wavelength range of 330-3300 nm. The crystal can be grown from a compound melt by a Czochralski method, a Kyropoulos method or a Bridgman method with the raw material being the synthetic compound Bi.sub.2 ZnB.sub.2 O.sub.7. Alternatively, the crystal may be grown from a high-temperature solution method by using Bi.sub.2 O.sub.3 as a flux. The crystal may be applied in nonlinear optical devices such as frequency doubling generators, frequency upconverters or downconverters, and optical parametric oscillators.
Type:
Grant
Filed:
April 8, 2009
Date of Patent:
October 23, 2012
Assignee:
Xingjiang Technical Institute of Physics & Chemistry, Chinese Academy of Sciences
Abstract: A method for forming a bulk crystal from precursors in the molten state, of solidification and growth around a seed of a material having a defined crystalline structure, includes subjecting the crystalline solid phase obtained at the end of the growth to a first controlled cooling step performed at a first higher cooling rate until a predetermined threshold temperature is reached, and to a subsequent controlled cooling step from the threshold temperature, performed at a second cooling rate lower than the first cooling rate.
Abstract: A polysilicon system comprises polysilicon in at least three form-factors, or shapes, providing for an enhanced loading efficiency of a mold or crucible. The system is used in processes to manufacture multi-crystalline or single crystal silicon.
Abstract: In a method for growing a silicon carbide single crystal on a silicon carbide single crystal substrate by contacting the substrate with a solution containing C by dissolving C into the melt that contains Si, Cr and X, which consists of at least one element of Sn, In and Ga, such that the proportion of Cr in the whole composition of the melt is in a range of 30 to 70 at. %, and the proportion of X is in a range of 1 to 25 at. %, and the silicon carbide crystal is grown from the solution.