Patents by Inventor Kamel Ounadjela

Kamel Ounadjela 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: 20080178793
    Abstract: Techniques for the formation of a higher purity semiconductor ingot using a low purity semiconductor feedstock include associating within a crucible a low-grade silicon feedstock, which crucible forms a process environment of said molten silicon. The process associates with the low-grade silicon feedstock, a quantity of the at least one metal and includes forming within the crucible a molten solution (e.g., a binary or ternary solution) of molten silicon and the metal at a temperature below the melting temperature of said low-grade silicon feedstock. A silicon seed crystal associates with the molten solution within the crucible for inducing directional silicon crystallization. The process further forms a silicon ingot from a portion of the molten solution in association with the silicon seed. The silicon ingot includes at least one silicon crystalline formation grown in the induced directional silicon crystallization process.
    Type: Application
    Filed: January 31, 2007
    Publication date: July 31, 2008
    Inventors: Matthias Heuer, Fritz Kirscht, Dieter Linke, Jean Patrice Rakotoniana, Kamel Ounadjela
  • Publication number: 20080157241
    Abstract: Techniques are here disclosed for a solar cell pre-processing method and system for annealing and gettering a solar cell semiconductor wafer having an undesirably high dispersion of transition metals, impurities and other defects. The process forms a surface contaminant layer on the solar cell semiconductor (e.g., silicon) wafer. A surface of the semiconductor wafer receives and holds impurities, as does the surface contaminant layer. The lower-quality semiconductor wafer includes dispersed defects that in an annealing process getter from the semiconductor bulk to form impurity cluster toward the surface contaminant layer. The impurity clusters form within the surface contaminant layer while increasing the purity level in wafer regions from which the dispersed defects gettered. Cooling follows annealing for retaining the impurity clusters and, thereby, maintaining the increased purity level of the semiconductor wafer in regions from which the impurities gettered.
    Type: Application
    Filed: December 30, 2006
    Publication date: July 3, 2008
    Inventors: Fritz Kirscht, Kamel Ounadjela, Jean Patrice Rakotoniana, Dieter Linke
  • Patent number: 7205164
    Abstract: Methods for patterning a magnetic cell junction and a topography used for and/or resulting from such methods are provided. In particular, a method is provided which includes etching portions of a topography adjacent to a patterned photoresist layer to a level within a cap film of the topography, removing etch residues from the topography and subsequently etching the remaining portions of the cap film to expose an uppermost magnetic layer. Another method is provided which includes patterning a dielectric mask layer above a patterned upper portion of a magnetic cell junction and ion milling a lower portion of the magnetic cell junction in alignment with the mask layer. An exemplary topography which may result and/or may be used for such methods includes a stack of layers having a dual layer cap film arranged above at least two magnetic layers spaced apart by a tunneling layer.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: April 17, 2007
    Assignee: Silicon Magnetic Systems
    Inventors: Sam Geha, Benjamin C. E. Schwarz, Chang Ju Choi, Biju Parameshwaran, Eugene Y. Chen, Helen L. Chung, Kamel Ounadjela, Witold Kula
  • Patent number: 7199055
    Abstract: A method for patterning a magnetic memory cell junction is provided herein, which includes etching exposed portions of a stack of layers to a level spaced above a tunneling barrier layer of the stack of layers. In addition, the method may include implanting dopants into exposed portions of the stack of layers. For example, the method may include oxidizing and/or nitriding the exposed portions of the stack of layers. In some embodiments, the steps of etching and implanting dopants may form an upper portion of the magnetic cell junction. Alternatively, the method may include alternating the steps of etching and implanting dopants throughout the thickness of the exposed portions of the stack of layers. In either case, the stack of layers may include a magnetic layer which includes a material adapted to prevent the introduction of dopants underlying the tunneling barrier layer during the step of implanting.
    Type: Grant
    Filed: February 25, 2004
    Date of Patent: April 3, 2007
    Assignee: Cypress Semiconductor Corp.
    Inventors: Eugene Y. Chen, Kamel Ounadjela, Witold Kula, Jerome S. Wolfman
  • Patent number: 6980468
    Abstract: A memory cell includes a magnetic cell junction having an antiferromagnetic layer within a portion of the cell junction that is adapted to characterize a logic state of a bit written to the junction. More specifically, a memory cell includes, an antiferromagnetic layer arranged in contact with an adjacent magnetic layer within a storing portion of a magnetic cell junction. Such a magnetic cell junction configuration and a method for programming a memory cell with such a cell junction configuration may be used to improve the write selectivity of a memory cell array and reduce the amount of current needed to write a bit to a memory cell. Moreover, a memory cell includes a magnetic cell junction having an aspect ratio less than 1.6. In addition, a memory cell includes at least two resistors.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: December 27, 2005
    Assignee: Silicon Magnetic Systems
    Inventor: Kamel Ounadjela
  • Patent number: 6897532
    Abstract: A method for forming a magnetic tunneling junction (MJT) is provided. In some embodiments, the method may include patterning one or more magnetic layers to form an upper portion of a MTJ. The method may further include patterning one or more additional layers to form a lower portion of the MTJ. In some cases, the lower portion may include a tunneling layer of the MTJ having a width greater than the upper portion. In addition, in some embodiments the method may further include patterning an electrode below the lower portion. In some cases, the electrode may include a lowermost layer with a thickness equal to or less than approximately 100 angstroms. In addition or alternatively, the electrode may have a width greater than the width of the tunneling layer. In yet other embodiments, the method may include forming spacers along the sidewalls of the upper and/or lower portions.
    Type: Grant
    Filed: April 15, 2002
    Date of Patent: May 24, 2005
    Assignee: Cypress Semiconductor Corp.
    Inventors: Benjamin C. E. Schwarz, Kamel Ounadjela
  • Patent number: 6861006
    Abstract: The invention relates to a method of creating pores in a polymer material in sheet form or a polymer layer such as a thin film with a thickness equal to around 100 nanometers, previously deposited on a metallic base. The invention further relates to a method of creating pores in a polymer material in sheet form, such as polycarbonate or any other equivalent material, the said method making it possible to obtain porous areas with controllable sizes and shapes, these areas being distributed according to densities and locations which can also be controlled.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: March 1, 2005
    Assignee: Universite Catholique de Louvain
    Inventors: Etienne Ferain, Roger Legras, Kamel Ounadjela
  • Patent number: 6798691
    Abstract: A magnetic memory cell and method for improving the write selectivity of memory cells in an MRAM array is provided herein. In particular, the magnetic memory cell may have a magnetic layer with a shape that is substantially asymmetrical about at least one axis of the magnetic layer. Such asymmetry may advantageously reduce and/or eliminate the effects of variations in the fabrication process. In addition, an asymmetrical memory shape may induce a relatively consistent equilibrium vector state, allowing a single switching mechanism to set the magnetic direction of the cell. Furthermore, a method is provided for programming a memory cell, in which the amount of current needed during a writing procedure is advantageously reduced relative to the amount of current needed in conventional writing procedures. In this manner, the asymmetrical memory cell and method produces a storage medium having overall power requirements less than those associated with symmetrical memory cells.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: September 28, 2004
    Assignee: Silicon Magnetic Systems
    Inventors: Kamel Ounadjela, Frederick B. Jenne
  • Publication number: 20040175848
    Abstract: A method for patterning a magnetic memory cell junction is provided herein, which includes etching exposed portions of a stack of layers to a level spaced above a tunneling barrier layer of the stack of layers. In addition, the method may include implanting dopants into exposed portions of the stack of layers. For example, the method may include oxidizing and/or nitriding the exposed portions of the stack of layers. In some embodiments, the steps of etching and implanting dopants may form an upper portion of the magnetic cell junction. Alternatively, the method may include alternating the steps of etching and implanting dopants throughout the thickness of the exposed portions of the stack of layers. In either case, the stack of layers may include a magnetic layer which includes a material adapted to prevent the introduction of dopants underlying the tunneling barrier layer during the step of implanting.
    Type: Application
    Filed: February 25, 2004
    Publication date: September 9, 2004
    Inventors: Eugene Y. Chen, Kamel Ounadjela, Witold Kula, Jerome S. Wolfman
  • Patent number: 6683815
    Abstract: A circuit is provided herein, which is adapted to supply different current magnitudes along opposing directions of a conductive line. Such a circuit may be particularly beneficial in compensating for the effects of unintentional magnetic coupling within MRAM devices. In addition, a method is provided herein for configuring a device having a magnetic memory array, which receives a first current magnitude along one direction and a substantially different current magnitude along an opposite direction of the magnetic memory array. Furthermore, a method is provided herein which assigns tunable current magnitudes for write operations along conductive lines of a memory circuit. Such tunable writing currents advantageously increase the write selectivity of the memory circuit. More specifically, the tunable writing currents compensate for ferromagnetic and antiferromagnetic coupling within magnetic memory cells caused by uneven surface topology and non-zero total magnetic moments, respectively.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: January 27, 2004
    Assignee: Silicon Magnetic Systems
    Inventors: Eugene Y. Chen, Kamel A. Ounadjela, Ashish Pancholy
  • Publication number: 20030087083
    Abstract: The invention relates to a method of creating pores in a polymer material in sheet form or a polymer layer such as a thin film with a thickness equal to around 100 nanometers, previously deposited on a metallic base. The invention further relates to a method of creating pores in a polymer material in sheet form, such as polycarbonate or any other equivalent material, the said method making it possible to obtain porous areas with controllable sizes and shapes, these areas being distributed according to densities and locations which can also be controlled.
    Type: Application
    Filed: June 27, 2002
    Publication date: May 8, 2003
    Inventors: Etienne Ferain, Roger Legras, Kamel Ounadjela