Patents by Inventor Joseph C. Holzer
Joseph C. Holzer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Publication number: 20020170485Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process for growing the single crystal silicon ingot comprises controlling (i) a growth velocity, v, (ii) an average axial temperature gradient, G0, during the growth of a constant diameter portion of the crystal over a temperature range from solidification to a temperature of no less than about 1325° C., and (iii) a cooling rate of the crystal from a solidification temperature to about 1,050° C., in order to cause the formation of an axially symmetrical segment which is substantially free of agglomerated intrinsic point defects.Type: ApplicationFiled: April 30, 2002Publication date: November 21, 2002Applicant: MEMC Electronic Materials, Inc.Inventors: Robert J. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Publication number: 20020139294Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process comprises controlling growth conditions, such as growth velocity, v, instantaneous axial temperature gradient, G0, and the cooling rate, within a range of temperatures at which silicon self-interstitials are mobile, in order to prevent the formation of these agglomerated defects. In ingot form, the axially symmetric region has a width, as measured from the circumferential edge of the ingot radially toward the central axis, which is at least about 30% the length of the radius of the ingot. The axially symmetric region additionally has a length, as measured along the central axis, which is at least about 20% the length of the constant diameter portion of the ingot.Type: ApplicationFiled: April 30, 2002Publication date: October 3, 2002Applicant: MEMC Electronic Materials, Inc.Inventors: Robert J. Falster, Joseph C. Holzer
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Publication number: 20020078880Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect and which is substantially free of agglomerated vacancy intrinsic point defects, wherein the first axially symmetric region has a width which is at least about 50% of the length of the radius of the ingot, and a process for the preparation thereof.Type: ApplicationFiled: October 24, 2001Publication date: June 27, 2002Applicant: MEMC Electronic Materials, Inc.Inventors: Robert J. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Patent number: 6409826Abstract: The present invention relates a process for the preparation of single crystal silicon, which contains an axially symmetric region which is free of agglomerated intrinsic point defects. The process for growing the single crystal silicon including controlling the ratio v/G0, where v is the growth velocity and G0 is the average axial temperature gradient during the growth of a constant diameter portion of the crystal over a temperature range from solidification to a temperature of no less than about 1325° C., and a cooling rate of the crystal from a solidification temperature to about 1,050° C., in order to cause the formation of an axially symmetrical segment which is substantially free of agglomerated intrinsic point defects. The control of V/G0 accomplished by controlling heat transfer at the melt/solid interface.Type: GrantFiled: March 23, 2001Date of Patent: June 25, 2002Assignee: MEMC Electronic Materials, Inc.Inventors: Robert A. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Patent number: 6409827Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process including controlling growth conditions, such as growth velocity, v, instantaneous axial temperature gradient, G0, and the cooling rate, within a range of temperatures at which silicon self-interstitials are mobile, in order to prevent the formation of these agglomerated defects. The control of G0 is accomplished by controlling heat transfer at the melt/solid interface.Type: GrantFiled: April 12, 2001Date of Patent: June 25, 2002Assignee: MEMC Electronic Materials, Inc.Inventors: Robert J. Falster, Joseph C. Holzer
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Patent number: 6379642Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect and which is substantially free of agglomerated vacancy intrinsic point defects, wherein the first axially symmetric region has a width which is at least about 50% of the length of the radius of the ingot, and a process for the preparation thereof.Type: GrantFiled: March 16, 1999Date of Patent: April 30, 2002Assignee: MEMC Electronic Materials, Inc.Inventors: Robert A. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Publication number: 20010039916Abstract: The present invention is directed to a set of epitaxial silicon wafers assembled in a wafer cassette, boat or other wafer carrier. Each wafer comprises a single crystal silicon substrate having an axially symmetric region in which silicon self-interstitials are the predominant intrinsic point defect and which is substantially free of agglomerated defects, and an epitaxial layer which is deposited upon a surface of the substrate and which is substantially free of grown-in defects caused by the presence of agglomerated silicon self-interstitial defects on the substrate surface upon which the epitaxial layer is deposited.Type: ApplicationFiled: June 5, 2001Publication date: November 15, 2001Inventors: Luciano Mule' Stagno, Lu Fei, Joseph C. Holzer, Harold W. Korb, Falster J. Falster
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Publication number: 20010025597Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process for growing the single crystal silicon ingot comprises controlling (i) a growth velocity, v, (ii) an average axial temperature gradient, G0, during the growth of a constant diameter portion of the crystal over a temperature range from solidification to a temperature of no less than about 1325° C., and (iii) a cooling rate of the crystal from a solidification temperature to about 1,050° C., in order to cause the formation of an axially symmetrical segment which is substantially free of agglomerated intrinsic point defects.Type: ApplicationFiled: March 23, 2001Publication date: October 4, 2001Inventors: Robert J. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Publication number: 20010020437Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process comprises controlling growth conditions, such as growth velocity, v, instantaneous axial temperature gradient, G0, and the cooling rate, within a range of temperatures at which silicon self-interstitials are mobile, in order to prevent the formation of these agglomerated defects. In ingot form, the axially symmetric region has a width, as measured from the circumferential edge of the ingot radially toward the central axis, which is at least about 30% the length of the radius of the ingot. The axially symmetric region additionally has a length, as measured along the central axis, which is at least about 20% the length of the constant diameter portion of the ingot.Type: ApplicationFiled: April 12, 2001Publication date: September 13, 2001Inventors: Robert J. Falster, Joseph C. Holzer
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Patent number: 6287380Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process comprises controlling growth conditions, such as growth velocity, v, instantaneous axial temperature gradient, G0, and the cooling rate, within a range of temperatures at which silicon self-interstitials are mobile, in order to prevent the formation of these agglomerated defects. In ingot form, the axially symmetric region has a width, as measured from the circumferential edge of the ingot radially toward the central axis, which is at least about 30% the length of the radius of the ingot. The axially symmetric region additionally has a length, as measured along the central axis, which is at least about 20% the length of the constant diameter portion of the ingot.Type: GrantFiled: April 9, 1998Date of Patent: September 11, 2001Assignee: MEMC Electronic Materials, Inc.Inventors: Robert J. Falster, Joseph C. Holzer
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Patent number: 6284039Abstract: The present invention is directed to a set of epitaxial silicon wafers assembled in a wafer cassette, boat or other wafer carrier. Each wafer comprises a single crystal silicon substrate having an axially symmetric region in which silicon self-interstitials are the predominant intrinsic point defect and which is substantially free of agglomerated defects, and an epitaxial layer which is deposited upon a surface of the substrate and which is substantially free of grown-in defects caused by the presence of agglomerated silicon self-interstitial defects on the substrate surface upon which the epitaxial layer is deposited.Type: GrantFiled: October 13, 1999Date of Patent: September 4, 2001Assignee: MEMC Electronic Materials, Inc.Inventors: Luciano Mule'Stagno, Lu Fei, Joseph C. Holzer, Harold W. Korb, Robert J. Falster
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Patent number: 6254672Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region which is free of agglomerated intrinsic point defects, and a process for the preparation thereof. The process for growing the single crystal silicon ingot comprises controlling (i) a growth velocity, v, (ii) an average axial temperature gradient, G0, during the growth of a constant diameter portion of the crystal over a temperature range from solidification to a temperature of no less than about 1325° C., and (iii) a cooling rate of the crystal from a solidification temperature to about 1,050° C., in order to cause the formation of an axially symmetrical segment which is substantially free of agglomerated intrinsic point defects.Type: GrantFiled: April 9, 1998Date of Patent: July 3, 2001Assignee: MEMC Electronic Materials, Inc.Inventors: Robert A. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Patent number: 6190631Abstract: A single crystal silicon wafer which, during the heat treatment cycles of essentially any electronic device manufacturing process, will form an ideal, non-uniform depth distribution of oxygen precipitates. The wafer is characterized in that is has a non-uniform distribution of crystal lattice vacancies, the concentration of vacancies in the bulk layer being greater than the concentration of vacancies in the surface layer and the vacancies having a concentration profile in which the peak density of the vacancies is at or near a central plane with the concentration generally decreasing from the position of peak density in the direction of a front surface of the wafer. In one embodiment, the wafer is further characterized in that it has a first axially symmetric region in which vacancies are the predominant intrinsic point defect and which is substantially free of agglomerated intrinsic point defects, wherein the first axially symmetric region comprises a central axis or has a width of at least about 15 mm.Type: GrantFiled: April 9, 1998Date of Patent: February 20, 2001Assignee: MEMC Electronic Materials, Inc.Inventors: Robert A. Falster, Joseph C. Holzer, Marco Cornara, Daniela Gambaro, Massimiliano Olmo, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Patent number: 5919302Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect and which is substantially free of agglomerated vacancy intrinsic point defects, wherein the first axially symmetric region comprises the central axis or has a width of at least about 15 mm, and a process for the preparation thereof.Type: GrantFiled: April 9, 1998Date of Patent: July 6, 1999Assignee: MEMC Electronic Materials, Inc.Inventors: Robert A. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
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Patent number: 5779791Abstract: A Czochralski method of producing a single crystal silicon ingot having a uniform thermal history from a silicon melt contained in a crucible coaxial with the ingot. In the process the pulling rate of the end-cone of the ingot is maintained at a relatively constant rate which is comparable to the pulling rate for the second half of the main body of the ingot. During the pulling of the end-cone of the crystal at a constant rate, the process may be further refined by, either independently or in combination, increasing the heat supplied to the melt, reducing the crystal rotation rate and/or reducing the crucible rotation rate. The second half of the main body of a single crystal silicon ingot grown in accordance with this process exhibits a relatively uniform axial concentration of flow pattern defects and amount of oxygen precipitated.Type: GrantFiled: August 8, 1996Date of Patent: July 14, 1998Assignee: MEMC Electronic Materials, Inc.Inventors: Harold W. Korb, Sadasivam Chandrasekhar, Robert J. Falster, Joseph C. Holzer, Kyong-Min Kim, Steven L. Kimbel, Larry E. Drafall
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Patent number: 5573680Abstract: A method of etching a generally planar surface of a semiconductor material to reveal flow pattern defects on the surface, by placing the material in a canted position, ranging from about 5.degree. to about 35.degree. from vertical, such that the generally planar surface of the material faces upwardly. The material is then immersed into a stagnant etchant solution. The surface of the material is etched such that bubbles nucleating at flow pattern defects on the surface of the canted material are released directly into the otherwise stagnant etchant solution.Type: GrantFiled: August 1, 1994Date of Patent: November 12, 1996Assignee: MEMC Electronic Materials, Inc.Inventors: Roger W. Shaw, Joseph C. Holzer
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Patent number: 5550374Abstract: Nondestructive methods and apparatus for determining a concentration of interstitial oxygen in a generally cylindrical body of crystalline silicon. The invention transmits an infrared (IR) beam through the body generally transverse to a longitudinal axis of the body and measures the absorption coefficient of an interstitial oxygen absorption band at a wavenumber W.sub.p of approximately 1720 cm.sup.-1. Further, the invention determines the concentration of interstitial oxygen in the body as a function of the measured absorption coefficient.Type: GrantFiled: May 12, 1994Date of Patent: August 27, 1996Assignee: MEMC Electronic Materials, Inc.Inventors: Joseph C. Holzer, Harold W. Korb, Klaus Drescher
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Patent number: 4990248Abstract: A water filter cartridge includes a reverse osmosis membrane permeator spirally wound on a central winding tube and surrounded by an impermeable barrier layer which is, in turn, surrounded by a spirally wound prefilter. A post-filter is placed centrally within the winding tube. The cartridge is designed for functional installation in a housing tube fastened and sealed to a valve plate at a first end and closed by a removable end cap at the other, second end. Feed water enters the cartridge through an inlet port in the valve plate at the first end at an outer radius to pass lengthwise in prefilter. Prefiltered water returns from the second end lengthwise through the reverse osmosis permeator to a waste-water outlet port in the valve plate at an intermediate radius. Product water which has permeated through the membrane flows inwardly through holes in the winding tube and into a clearance space surrounding the central post-filter.Type: GrantFiled: June 16, 1988Date of Patent: February 5, 1991Assignee: Eastman Kodak CompanyInventors: Barry M. Brown, Evan A. Edwards, Joseph C. Holzer, Augustine Pavel, Frederick Tone, Henry L. West
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Patent number: 4767531Abstract: A retractor handle is attached to the retraction end of a core wound permeator or filter module for withdrawing the module form its containment housing without requiring special tools. The retraction handle can be a resin pull ring flexibly attached to a flange of a plug that closes the retraction end of the core of the permeator or filter module. The retraction handle can also be a wire pull ring having ends seated in sockets formed in a plugged end region of the core.Type: GrantFiled: November 2, 1987Date of Patent: August 30, 1988Assignee: Eastman Kodak CompanyInventor: Joseph C. Holzer
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Patent number: 4564411Abstract: An apparatus having a friction-feed and surface-driven roller mechanism for producing laminated labels from a strip of base-tape material and a strip of transparent overlay-tape material. The apparatus is readily mountable to and adapted for use with many different types of typewriters and printers without permanent modification thereto. One embodiment is adapted for use with a typewriter or printer having a rolling platen. Another embodiment is adapted for use with a printer having a fixed platen and sheet-feeding tractor mechanism. Yet another embodiment is adapted for use with a typewriter having a movable, rolling platen. In all embodiments, there is provided a roller mechanism having a frictionally surface-driven feed roller engaging either the typewriter platen or a separate drive roll for pulling the overlay-tape and base-tape material into and through the roller mechanism and pressing the adhesive surface of the overlay-tape material into contact with the base-tape material.Type: GrantFiled: December 13, 1983Date of Patent: January 14, 1986Assignee: Gaylord Bros., Inc.Inventor: Joseph C. Holzer