Patents by Inventor James S. Im

James S. Im 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).

  • Publication number: 20140193935
    Abstract: Collections of laterally crystallized semiconductor islands for use in thin film transistors and systems and methods for making same are described. A display device includes a plurality of thin film transistors (TFTs) on a substrate, such that the TFTs are spaced apart from each other and each include a channel region that has a crystalline microstructure and a direction along which a channel current flows. The channel region of each of the TFTs contains a crystallographic grain that spans the length of that channel region along its channel direction. Each crystallographic grain in the channel region of each of the TFTs is physically disconnected from and crystallographically uncorrelated with each crystallographic grain in the channel region of each adjacent TFT.
    Type: Application
    Filed: October 16, 2013
    Publication date: July 10, 2014
    Applicant: THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
    Inventors: James S. IM, Ui-Jin CHUNG
  • Patent number: 8734584
    Abstract: In accordance with one aspect, the present invention provides a method for providing polycrystalline films having a controlled microstructure as well as a crystallographic texture. The methods provide elongated grains or single-crystal islands of a specified crystallographic orientation. In particular, a method of processing a film on a substrate includes generating a textured film having crystal grains oriented predominantly in one preferred crystallographic orientation; and then generating a microstructure using sequential lateral solidification crystallization that provides a location-controlled growth of the grains orientated in the preferred crystallographic orientation.
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: May 27, 2014
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: James S. Im, Paul C. van der Wilt
  • Patent number: 8715412
    Abstract: Systems for processing thin films having variable thickness are provided. A crystalline film includes a first crystalline region having a first film thickness and a first crystalline grain structure; and a second crystalline region having a second film thickness and a second crystalline grain structure. The first film thickness is greater than the second film thickness and the first and second film thicknesses are selected to provide a crystalline region having the degree and orientation of crystallization that is desired for a device component.
    Type: Grant
    Filed: January 14, 2013
    Date of Patent: May 6, 2014
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Patent number: 8680427
    Abstract: A device on a supporting substrate is provided including a semiconductor film, having two or more rectangular crystalline regions spaced from each other, wherein each of the two or more rectangular crystalline regions comprises one single crystal region. The device can further include two or more thin-film transistors, wherein each of the two or more thin-film transistors comprises one or more active-channel regions. Each of the one or more active-channel regions can comprise at least one of said two or more rectangular crystalline regions. The device can further include an integrated circuit which comprises of the two or more thin-film transistors.
    Type: Grant
    Filed: April 7, 2009
    Date of Patent: March 25, 2014
    Assignee: The Trustees Of Columbia University in The City Of New York
    Inventors: James S. Im, Robert S. Sposili, Mark A. Crowder
  • Patent number: 8663387
    Abstract: A method and system for processing at least one portion of a thin film sample on a substrate, with such portion of the film sample having a first boundary and a second boundary. One or more first areas of the film sample are successively irradiated by first beamlets of an irradiation beam pulse so that the first areas are melted throughout their thickness and allowed to re-solidify and crystallize thereby having grains grown therein. Thereafter, one or more second areas of the film sample are irradiated by second beamlets so that the second areas are melted throughout their thickness. At least two of the second areas partially overlap a particular area of the re-solidified and crystallized first areas such that the grains provided in the particular area grow into each of the at least two second areas upon re-solidification thereof.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: March 4, 2014
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Publication number: 20140045346
    Abstract: The disclosed subject matter relates to the use of laser crystallization of thin films to create epitaxially textured crystalline thick films. In one or more embodiments, a method for preparing a thick crystalline film includes providing a film for crystallization on a substrate, wherein at least a portion of the substrate is substantially transparent to laser irradiation, said film including a seed layer having a predominant surface crystallographic orientation; and a top layer disposed above the seed layer; irradiating the film from the back side of the substrate using a pulsed laser to melt a first portion of the top layer at an interface with the seed layer while a second portion of the top layer remains solid; and re-solidifying the first portion of the top layer to form a crystalline laser epitaxial with the seed layer thereby releasing heat to melt an adjacent portion of the top layer.
    Type: Application
    Filed: October 14, 2013
    Publication date: February 13, 2014
    Applicant: THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
    Inventor: James S. IM
  • Publication number: 20140045347
    Abstract: In some embodiments, a method of processing a film is provided, the method comprising defining a plurality of spaced-apart regions to be pre-crystallized within the film, the film being disposed on a substrate and capable of laser-induced melting; generating a laser beam having a fluence that is selected to form a mixture of solid and liquid in the film and where a fraction of the film is molten throughout its thickness in an irradiated region; positioning the film relative to the laser beam in preparation for at least partially pre-crystallizing a first region of said plurality of spaced-apart regions; directing the laser beam onto a moving at least partially reflective optical element in the path of the laser beam, the moving optical element redirecting the beam so as to scan a first portion of the first region with the beam in a first direction at a first velocity, wherein the first velocity is selected such that the beam irradiates and forms the mixture of solid and liquid in the first portion of the firs
    Type: Application
    Filed: October 16, 2013
    Publication date: February 13, 2014
    Applicant: The Trustees Of Columbia University In The City Of New York
    Inventor: James S. IM
  • Publication number: 20140001164
    Abstract: Methods and systems for processing a thin film are disclosed. Thin films are loaded onto two different loading fixtures, laser beam pulses are split into first and second laser beam pulses, the thin film loaded on one loading fixture is irradiated with the first laser beam pulses to induce crystallization while the thin film loaded on the other loading fixture is irradiated with the second laser beam pulses. At least a portion of the thin film loaded on the first and second loading fixtures is irradiated. The laser source system includes first and second laser sources and an integrator that combines the laser beam pulses to form combined laser beam pulses. The methods and system further utilize additional loading fixtures for processing additional thin film samples. The irradiation of additional thin film samples can be performed while thin film samples are being loaded onto the remaining loading fixtures.
    Type: Application
    Filed: August 5, 2013
    Publication date: January 2, 2014
    Applicant: THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
    Inventor: James S. IM
  • Patent number: 8617313
    Abstract: A system for preparing a semiconductor film, the system including: a laser source; optics to form a line beam, a stage to support a sample capable of translation; memory for storing a set of instructions, the instructions including irradiating a first region of the film with a first laser pulse to form a first molten zone, said first molten zone having a maximum width (Wmax) and a minimum width (Wmin), wherein the first molten zone crystallizes to form laterally grown crystals; laterally moving the film in the direction of lateral growth a distance greater than about one-half Wmax and less than Wmin; and irradiating a second region of the film with a second laser pulse to form a second molten zone, wherein the second molten zone crystallizes to form laterally grown crystals that are elongations of the crystals in the first region, wherein laser optics provide Wmax less than 2×Wmin.
    Type: Grant
    Filed: July 12, 2012
    Date of Patent: December 31, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: James S. Im, Paul C. Van Der Wilt
  • Patent number: 8614471
    Abstract: Collections of laterally crystallized semiconductor islands for use in thin film transistors and systems and methods for making same are described. A display device includes a plurality of thin film transistors (TFTs) on a substrate, such that the TFTs are spaced apart from each other and each include a channel region that has a crystalline microstructure and a direction along which a channel current flows. The channel region of each of the TFTs contains a crystallographic grain that spans the length of that channel region along its channel direction. Each crystallographic grain in the channel region of each of the TFTs is physically disconnected from and crystallographically uncorrelated with each crystallographic grain in the channel region of each adjacent TFT.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: December 24, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: James S. Im, Ui-Jin Chung
  • Patent number: 8598588
    Abstract: In some embodiments, a method of processing a film is provided, the method comprising defining a plurality of spaced-apart regions to be pre-crystallized within the film, the film being disposed on a substrate and capable of laser-induced melting; generating a laser beam having a fluence that is selected to form a mixture of solid and liquid in the film and where a fraction of the film is molten throughout its thickness in an irradiated region; positioning the film relative to the laser beam in preparation for at least partially pre-crystallizing a first region of said plurality of spaced-apart regions; directing the laser beam onto a moving at least partially reflective optical element in the path of the laser beam, the moving optical element redirecting the beam so as to scan a first portion of the first region with the beam in a first direction at a first velocity, wherein the first velocity is selected such that the beam irradiates and forms the mixture of solid and liquid in the first portion of the firs
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: December 3, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Publication number: 20130316548
    Abstract: High throughput systems and processes for recrystallizing thin film semiconductors that have been deposited at low temperatures on a substrate are provided. A thin film semiconductor workpiece (170) is irradiated with a laser beam (164) to melt and recrystallize target areas of the surface exposed to the laser beam. The laser beam is shaped into one or more beam lets using patterning masks (150). The mask patterns have suitable dimensions and orientations to pattern the laser beam radiation so that the areas targeted by the beamlets have dimensions and orientations that are conducive to semiconductor recrystallization. The workpiece is mechanically translated along linear paths relative to the laser beam to process the entire surface of the work piece at high speeds. Position sensitive triggering of a laser can be used generate laser beam pulses to melt and recrystallize semiconductor material at precise locations on the surface of the workpiece while it is translated on a motorized stage (180).
    Type: Application
    Filed: August 1, 2013
    Publication date: November 28, 2013
    Applicant: THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
    Inventor: James S. IM
  • Patent number: 8569155
    Abstract: The disclosed subject matter generally relates a method of irradiating a large area thin film with a pulsed light source. In some embodiments, the disclosed subject matter particularly relates to utilizing flash lamp annealing in combination with patterning techniques for making thin film devices. The flash lamp annealing can trigger lateral growth crystallization or explosive crystallization in large area thin films. In some embodiments, capping layers or proximity masks can be used in conjunction with the flash lamp annealing.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: October 29, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Publication number: 20130280924
    Abstract: The disclosed systems and method for non-periodic pulse sequential lateral solidification relate to processing a thin film. The method for processing a thin film, while advancing a thin film in a selected direction, includes irradiating a first region of the thin film with a first laser pulse and a second laser pulse and irradiating a second region of the thin film with a third laser pulse and a fourth laser pulse, wherein the time interval between the first laser pulse and the second laser pulse is less than half the time interval between the first laser pulse and the third laser pulse. In some embodiments, each pulse provides a shaped beam and has a fluence that is sufficient to melt the thin film throughout its thickness to form molten zones that laterally crystallize upon cooling. In some embodiments, the first and second regions are adjacent to each other. In some embodiments, the first and second regions are spaced a distance apart.
    Type: Application
    Filed: May 13, 2013
    Publication date: October 24, 2013
    Inventors: James S. IM, Ui-Jin CHUNG, Alexander B. LIMANOV, Paul C. VAN DER WILT
  • Patent number: 8557040
    Abstract: The disclosed subject matter relates to the use of laser crystallization of thin films to create epitaxially textured crystalline thick films. In one or more embodiments, a method for preparing a thick crystalline film includes providing a film for crystallization on a substrate, wherein at least a portion of the substrate is substantially transparent to laser irradiation, said film including a seed layer having a predominant surface crystallographic orientation; and a top layer disposed above the seed layer; irradiating the film from the back side of the substrate using a pulsed laser to melt a first portion of the top layer at an interface with the seed layer while a second portion of the top layer remains solid; and re-solidifying the first portion of the top layer to form a crystalline laser epitaxial with the seed layer thereby releasing heat to melt an adjacent portion of the top layer.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: October 15, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Patent number: 8507368
    Abstract: High throughput systems and processes for recrystallizing thin film semiconductors that have been deposited at low temperatures on a substrate are provided. A thin film semiconductor workpiece is irradiated with a laser beam to melt and recrystallize target areas of the surface exposed to the laser beam. The laser beam is shaped into one or more pulses. The beam pulses have suitable dimensions and orientations to pattern the laser beam radiation so that the areas targeted by the beam have dimensions and orientations that are conductive to semiconductor recrystallization. The workpiece is mechanically translated along linear paths relative to the laser beam to process the entire surface of the workpiece at high speeds. Position sensitive triggering of a laser can be used to generate laser beam pulses to melt and recrystallize semiconductor material at precise locations on the surface of the workpiece while it is translated on a motorized stage.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: August 13, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Publication number: 20130201634
    Abstract: The disclosure relates to methods and systems for single-scan line-scan crystallization using superimposed scanning elements. In one aspect, the method includes generating a plurality of laser beam pulses from a pulsed laser source, wherein each laser beam pulse has a fluence selected to melt the thin film and, upon cooling, induce crystallization in the thin film; directing a first laser beam pulse onto a thin film using a first beam path; advancing the thin film at a constant first scan velocity in a first direction; and deflecting a second laser beam pulse from the first beam path to a second beam path using an optical scanning element such that the deflection results in the film experiencing a second scan velocity of the laser beam pulses relative to the thin film, wherein the second scan velocity is less than the first scan velocity.
    Type: Application
    Filed: December 30, 2010
    Publication date: August 8, 2013
    Applicant: COLUMBIA UNIVERSITY
    Inventors: James S. Im, Paul C. Van Der Wilt
  • Patent number: 8479681
    Abstract: High throughput systems and processes for recrystallizing thin film semiconductors that have been deposited at low temperatures on a substrate are provided. A thin film semiconductor workpiece (170) is irradiated with a laser beam (164) to melt and recrystallize target areas of the surface exposed to the laser beam. The laser beam is shaped into one or more beamlets using patterning masks (150). The mask patterns have suitable dimensions and orientations to pattern the laser beam radiation so that the areas targeted by the beamlets have dimensions and orientations that are conducive to semiconductor recrystallization. The workpiece is mechanically translated along linear paths relative to the laser beam to process the entire surface of the work piece at high speeds. Position sensitive triggering of a laser can be used generate laser beam pulses to melt and recrystallize semiconductor material at precise locations on the surface of the workpiece while it is translated on a motorized stage (180).
    Type: Grant
    Filed: February 1, 2011
    Date of Patent: July 9, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Patent number: 8476144
    Abstract: An arrangement, process and mask for implementing single-scan continuous motion sequential lateral solidification of a thin film provided on a sample such that artifacts formed at the edges of the beamlets irradiating the thin film are significantly reduced. According to this invention, the edge areas of the previously irradiated and resolidified areas which likely have artifacts provided therein are overlapped by the subsequent beamlets. In this manner, the edge areas of the previously resolidified irradiated areas and artifacts therein are completely melted throughout their thickness. At least the subsequent beamlets are shaped such that the grains of the previously irradiated and resolidified areas which border the edge areas melted by the subsequent beamlets grow into these resolidifying edges areas so as to substantially reduce or eliminate the artifacts.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: July 2, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventor: James S. Im
  • Patent number: 8445365
    Abstract: A method of processing a polycrystalline film on a substrate includes generating laser pulses, directing the laser pulses through a mask to generate patterned laser beams, each having a length l?, a width w?, and a spacing between adjacent beams d?; irradiating a region of the film with the patterned beams, said beams having an intensity sufficient to melt and to induce crystallization of the irradiated portion of the film, wherein the film region is irradiated n times; and after irradiation of each film portion, translating the film and/or the mask, in the x- and y-directions. The distance of translation in the y-direction is about l?/n??, where ? is a value selected to overlap the beamlets from one irradiation step to the next. The distance of translation in the x-direction is selected such that the film is moved a distance of about ?? after n irradiations, where ??=w?+d?.
    Type: Grant
    Filed: June 21, 2011
    Date of Patent: May 21, 2013
    Assignee: The Trustees of Columbia University in the City of New York
    Inventors: James S. Im, Paul C. Van Der Wilt