Patents by Inventor John L. Fitz

John L. Fitz 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).

  • Patent number: 7838867
    Abstract: The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure resulting in an underlying L-shaped structure. A sacrificial spacer layer is deposited in the trench. The waveguide is created in the trench on the sacrificial spacer layer using a mask layer to angle the vertex of the L-shaped structure. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: November 23, 2010
    Assignee: United States of America as represented by the Director, National Security Agency, The
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7838866
    Abstract: The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure resulting in an underlying L-shaped structure. A sacrificial spacer layer is deposited in the trench. The waveguide is created in the trench on the sacrificial spacer layer using a mask layer to angle the vertex of the L-shaped structure. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: November 23, 2010
    Assignee: The United States of America as represented by the Director of the National Security Agency
    Inventors: John L. Fitz, Daniel Stephen Hinkel, Scott C. Horst
  • Patent number: 7833828
    Abstract: A method of creating a patterned device by selecting a substrate; forming a first step on the substrate; depositing a sacrificial layer along the first step and the substrate; depositing a second step on a portion of the sacrificial layer; depositing a second layer on each of a portion of the substrate, sacrificial layer and second step that shares a common resistance to removal by a same agent as the substrate, the first step and the second step; removing a portion of the sacrificial layer so that a gap is created between the second layer and the first step, wherein a portion of the sacrificial layer remains such that the second layer remains; and processing the substrate beneath the gap created between the second layer and the first step.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: November 16, 2010
    Assignee: United States of America as represented by the Director, The National Security Agency
    Inventors: John L. Fitz, Harris Turk
  • Patent number: 7741136
    Abstract: The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure resulting in an underlying L-shaped structure. A sacrificial spacer layer is deposited in the trench. The waveguide is created in the trench on the sacrificial spacer layer using a mask layer to angle the vertex of the L-shaped structure. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
    Type: Grant
    Filed: May 13, 2009
    Date of Patent: June 22, 2010
    Assignee: The United States of America as represented by the Director, National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7700391
    Abstract: The present invention is a method of fabricating an optical device using multiple sacrificial spacer layers. The first step in this process is to fabricate the underlying base structure and deposit an optical structure thereon. A facet is then created at the ends of the optical structure and alternating sacrificial and intermediate layers are fabricated on the device. A mask layer is deposited on the structure, with openings created in the layers to allow use of an etchant. User-defined portions of the spacer layers are subsequently removed with the etchant to create air gaps between the intermediate layers.
    Type: Grant
    Filed: May 5, 2009
    Date of Patent: April 20, 2010
    Assignee: U.S. Government as Represented by the Director, National Security Agency, The
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7700387
    Abstract: The present invention is a method of fabricating an optical device using multiple sacrificial spacer layers. The first step in this process is to fabricate the underlying base structure and deposit an optical structure thereon. A facet is then created at the ends of the optical structure and alternating sacrificial and intermediate layers are fabricated on the device. A mask layer is deposited on the structure, with openings created in the layers to allow use of an etchant. User-defined portions of the spacer layers are subsequently removed with the etchant to create air gaps between the intermediate layers.
    Type: Grant
    Filed: May 5, 2009
    Date of Patent: April 20, 2010
    Assignee: The United States of America as Represented by the Director, National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7678593
    Abstract: The present invention is a method of fabricating an optical device using multiple sacrificial spacer layers. The first step in this process is to fabricate the underlying base structure and deposit an optical structure thereon. A facet is then created at the ends of the optical structure and alternating sacrificial and intermediate layers are fabricated on the device. A mask layer is deposited on the structure, with openings created in the layers to allow use of an etchant. User-defined portions of the spacer layers are subsequently removed with the etchant to create air gaps between the intermediate layers.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: March 16, 2010
    Assignee: The United States of America, as represented by the Director, National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7611914
    Abstract: The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure resulting in an underlying L-shaped structure. A sacrificial spacer layer is deposited in the trench. The waveguide is created in the trench on the sacrificial spacer layer using a mask layer to angle the vertex of the L-shaped structure. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
    Type: Grant
    Filed: June 16, 2006
    Date of Patent: November 3, 2009
    Assignee: The United States of America as represented by the Director, National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7599594
    Abstract: The present invention is a method of fabricating a waveguide using a sacrificial spacer layer. The first step in this process is to fabricate the underlying optical semiconductor structure. A trench is then etched in this structure and a sacrificial spacer layer is deposited in the trench. The waveguide is then created in the trench on the sacrificial spacer layer. User-defined portions of the sacrificial spacer layer are subsequently removed to create air gaps between the waveguide and the sidewalls of the trench in the optical semiconductor.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: October 6, 2009
    Assignee: The United States of America as represented by Director, National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst
  • Patent number: 7595221
    Abstract: A method of fabricating a device using a sacrificial layer by selecting a substrate; forming a first step on the substrate, where the first step is formed from a second material; depositing a sacrificial layer along the first step and the substrate; depositing a second step on a portion of the sacrificial layer; depositing a second layer on each of a portion of the substrate, sacrificial layer and second step that shares a common resistance to removal by a same agent as the substrate, the first step and the second step; removing the second step; removing a portion of the sacrificial layer such that a gap is created between the second layer and the first step, wherein at least a portion of the sacrificial layer remains such that the second layer adhered to the substrate remains; and processing the substrate beneath the gap.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: September 29, 2009
    Assignee: The United States of America as represented by the Director, National Security Agency
    Inventors: John L. Fitz, Harris Turk
  • Patent number: 7531382
    Abstract: A method of creating a patterned device by selecting a substrate; depositing a mask layer on the substrate; forming a first step on the mask layer; depositing a sacrificial layer along the first step and the mask layer; depositing a blocking layer on the sacrificial layer; removing a portion of the blocking layer, where a portion of the blocking layer remains such that no gap exists between the blocking layer and the sacrificial layer and the remaining blocking layer is adhered to the mask layer; removing a portion of the sacrificial layer such that a gap is created between the blocking layer and the first step, where a portion of the sacrificial layer remains such that the blocking layer adhered to the mask layer remains; etching the mask layer beneath the gap; and processing the substrate through the gap in the mask layer.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: May 12, 2009
    Assignee: The United States of America as represented by the Director National Security Agency
    Inventors: John L. Fitz, Harris Turk
  • Patent number: 7010187
    Abstract: The present invention is a photonic logic circuit for multimode optical signals. The device includes a laser cavity having at least four conduits, the combination forming a substantially X-shaped construction. An output is attached to each conduit for transmission of the optical signals from the cavity. At least one input is connected to the laser cavity. The input is connected to an upper or lower edge of the laser cavity. These are the edges that do not include conduits. A bias contact is connected to the cavity and the two lower conduits. The bias contact is used to pump the photonic device. Preset contacts are attached to each of the upper two conduits and their respective outputs. The preset contacts are used to control the logic function of the photonic logic device. Altering current pump settings between the respective contacts controls the direction of lasing between outputs of the photonic device and the logic function performed.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: March 7, 2006
    Assignee: The United States of America as represented by the National Security Agency
    Inventor: John L. Fitz
  • Patent number: 6835581
    Abstract: A method of simultaneously depositing dielectric layers on both facets of an optical device and devices made therefrom. The steps of the method are selecting a substrate; forming an optical device on the substrate; forming an active-layer pumping structure on the optical device; forming facets in the optical device with at least two different orientations; and coating a user-definable number of dielectric layers onto the facets. The dielectric layers may be deposited in single dielectric layers or in pairs of dielectric layers. Single layers are useful for forming optical amplifiers while dielectric pairs are useful for forming lasers.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: December 28, 2004
    Assignee: The United States of America as represented by the National Security
    Inventors: John L. Fitz, Daniel Stephen Hinkel, Scott C. Horst, Harris Turk
  • Patent number: 6541288
    Abstract: A method of measuring reflectivity of a semiconductor laser facet by first fabricating first and second semiconductor lasers. The reflectance of the facets of the lasers are then determined. The threshold current densities of the lasers are then measured. If the reflectance of the first facet of the first semiconductor laser is modified then setting u=1, x=1, and y=1. If the reflectance of the first facet and the second facet of the first semiconductor laser are modified to the same extent then setting u=1, x=1, and y=0.5. The threshold current density of the first semiconductor laser after reflectivity modification is then measured. The reflectance of the modified first semiconductor laser is then calculated as follows: R1=(u){(R0)Exp[x−(2y[(1/L1)−(1/L2)]L1(J1−J3)/(J1−J2))]}.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: April 1, 2003
    Assignee: The United States of America as represented by the National Security Agency
    Inventor: John L. Fitz
  • Publication number: 20030035453
    Abstract: A method of simultaneously depositing dielectric layers on both facets of an optical device and devices made therefrom. The steps of the method are selecting a substrate; forming an optical device on the substrate; forming an active-layer pumping structure on the optical device; forming facets in the optical device with at least two different orientations; and coating a user-definable number of dielectric layers onto the facets. The dielectric layers may be deposited in single dielectric layers or in pairs of dielectric layers. Single layers are useful for forming optical amplifiers while dielectric pairs are useful for forming lasers.
    Type: Application
    Filed: August 17, 2001
    Publication date: February 20, 2003
    Inventors: John L. Fitz, Daniel Stephen Hinkel, Scott C. Horst, Harris Turk
  • Patent number: 4825442
    Abstract: An optically controlled laser device is used to perform digital logic functions. The device comprises a single mode semiconductor laser including a waveguide for coupling light into the lasing caving at an angle at or near normal incidence with respect to the laser radiation generated by the laser. The single mode properties of the laser are achieved by index guiding. The coupled light interacts with the laser radiation in a small region of the lasing cavity creating a perturbation that quenches the laser output, whereby input of the coupled light enables the laser device to perform logic functions.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: April 25, 1989
    Assignee: U.S. Government as represented by Director, National Security Agency
    Inventor: John L. Fitz
  • Patent number: RE45084
    Abstract: The present invention is a method of fabricating an optical device using multiple sacrificial spacer layers. The first step in this process is to fabricate the underlying base structure and deposit an optical structure thereon. A facet is then created at the ends of the optical structure and alternating sacrificial and intermediate layers are fabricated on the device. A mask layer is deposited on the structure, with openings created in the layers to allow use of an etchant. User-defined portions of the spacer layers are subsequently removed with the etchant to create air gaps between the intermediate layers.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: August 19, 2014
    Assignee: National Security Agency
    Inventors: John L. Fitz, Daniel S. Hinkel, Scott C. Horst