Patents by Inventor Haydn James Gregory

Haydn James Gregory 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: 6816224
    Abstract: A pixel cell array of a light valve does not rely upon photolithography to define inter-pixel spacing. Instead, adjacent pixels of the array are electronically insulated from one another by spacers formed by etching a dielectric layer conforming to sidewalls of a patterned sacrificial layer. Removal of the sacrificial layer, followed by formation of a metal layer over the dielectric spacer structures and chemical-mechanical polishing of the metal layer, completes fabrication of the array. The thickness of the spacer sidewalls, and hence inter-pixel spacing, is determined by the rate of formation of the conforming dielectric layer. This rate can be precisely controlled to produce spacer structures having a thickness of less than the minimum linewidth of a given photolithography system. In this manner, pixel arrays having significantly reduced inter-pixel spacing and correspondingly higher cell densities can be created.
    Type: Grant
    Filed: July 24, 2001
    Date of Patent: November 9, 2004
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6528375
    Abstract: A bipolar transistor compatible with CMOS processes utilizes only a single layer of polysilicon while maintaining the low base resistance associated with conventional double-polysilicon bipolar designs. Dopant is implanted to form the intrinsic base through the same dielectric window in which the polysilicon emitter contact component is later created. Following poly deposition within the window and etch to create the polysilicon emitter contact component, large-angle tilt ion implantation is employed to form a link base between the intrinsic base and a subsequently-formed base contact region. Tilted implantation enables the link base region to extend underneath the edges of the polysilicon emitter contact component, creating a low resistance path between the intrinsic base and the extrinsic base. Fabrication of the device is much simplified over a conventional double-poly transistor, particularly if tilted implantation is already employed in the process flow to form an associated structure such as an LDMOS.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: March 4, 2003
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6420771
    Abstract: A bipolar transistor is vertically isolated from underlying silicon by an isolation layer of conductivity type opposite that of the collector. This isolation layer lies beneath the heavily doped buried layer portion of the collector, and is formed either by ion implantation prior to epitaxial growth of well regions, or by high energy ion implantation into the substrate prior to formation of the well and the heavily doped buried collector layer. Utilization of trench lateral isolation extending into the semiconductor material beyond the isolation layer permits blanket implant of the isolation layer, obviating the need for an additional masking step.
    Type: Grant
    Filed: February 5, 2001
    Date of Patent: July 16, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6392734
    Abstract: A light valve array features discrete pixel cells electronically isolated by dielectric spacers formed by etching a dielectric layer conforming to sidewalls of a patterned first metal layer. Formation of a second metal layer over the dielectric spacer structures, followed by chemical-mechanical polishing of the second metal layer to stop on the tips of the sidewall spacers, completes fabrication of the array. Interpixel regions corresponding to the dielectric spacers are substantially shielded from incident light by projecting metal edges of the electrodes supported by the curved upper surface of the spacer structures.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: May 21, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6392733
    Abstract: A light valve array features discrete pixel cells electronically isolated by dielectric spacers formed by etching a dielectric layer conforming to sidewalls of a patterned sacrificial layer. The sacrificial layer is then removed selective to the dielectric spacer structures. A metal layer is formed over the dielectric spacer structures. Chemical-mechanical polishing of the metal layer to stop on the tips of the sidewall spacers completes fabrication of the array. Interpixel regions corresponding to the dielectric spacers are substantially shielded from incident light by projecting electrode edges formed over the curved upper surface of the spacer structures.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: May 21, 2002
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6306561
    Abstract: A pixel cell array of a light valve does not rely upon photolithography to define inter-pixel spacing. Instead, adjacent pixels of the array are electronically insulated from one another by spacers formed by etching a dielectric layer conforming to sidewalls of a patterned first metal layer. Formation of a second metal layer over the dielectric spacer structures, followed by chemical-mechanical polishing of the second metal layer to reveal the tops of the sidewall spacers, completes fabrication of the array. The thickness of the spacer sidewalls, and hence inter-pixel spacing, is determined by the rate of formation of the conforming dielectric layer. This rate can be precisely controlled to produce spacer structures having a thickness less than the minimum linewidth of a given photolithography system. In this manner, pixel arrays having greatly reduced inter-pixel spacing and correspondingly higher cell densities can be created.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: October 23, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6303273
    Abstract: A pixel cell array of a light valve does not rely upon photolithography to define inter-pixel spacing. Instead, adjacent pixels of the array are electronically insulated from one another by spacers formed by etching a dielectric layer conforming to sidewalls of a patterned sacrificial layer. Removal of the sacrificial layer, followed by formation of a metal layer over the dielectric spacer structures and chemical-mechanical polishing of the metal layer, completes fabrication of the array. The thickness of the spacer sidewalls, and hence inter-pixel spacing, is determined by the rate of formation of the conforming dielectric layer. This rate can be precisely controlled to produce spacer structures having a thickness of less than the minimum linewidth of a given photolithography system. In this manner, pixel arrays having significantly reduced inter-pixel spacing and correspondingly higher cell densities can be created.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: October 16, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Publication number: 20010015470
    Abstract: A bipolar transistor is vertically isolated from underlying silicon by an isolation layer of conductivity type opposite that of the collector. This isolation layer lies beneath the heavily doped buried layer portion of the collector, and is formed either by ion implantation prior to epitaxial growth of well regions, or by high energy ion implantation into the substrate prior to formation of the well and the heavily doped buried collector layer. Utilization of trench lateral isolation extending into the semiconductor material beyond the isolation layer permits blanket implant of the isolation layer, obviating the need for an additional masking step.
    Type: Application
    Filed: February 5, 2001
    Publication date: August 23, 2001
    Applicant: NATIONAL SEMICONDUCTOR CORPORATION
    Inventor: Haydn James Gregory
  • Publication number: 20010010382
    Abstract: A bipolar transistor compatible with CMOS processes utilizes only a single layer of polysilicon while maintaining the low base resistance associated with conventional double-polysilicon bipolar designs. Dopant is implanted to form the intrinsic base through the same dielectric window in which the polysilicon emitter contact component is later created. Following poly deposition within the window and etch to create the polysilicon emitter contact component, large-angle tilt ion implantation is employed to form a link base between the intrinsic base and a subsequently-formed base contact region. Tilted implantation enables the link base region to extend underneath the edges of the polysilicon emitter contact component, creating a low resistance path between the intrinsic base and the extrinsic base. Fabrication of the device is much simplified over a conventional double-poly transistor, particularly if tilted implantation is already employed in the process flow to form an associated structure such as an LDMOS.
    Type: Application
    Filed: March 20, 2001
    Publication date: August 2, 2001
    Inventor: Haydn James Gregory
  • Patent number: 6262472
    Abstract: A bipolar transistor compatible with CMOS processes utilizes only a single layer of polysilicon while maintaining the low base resistance associated with conventional double-polysilicon bipolar designs. Dopant is implanted to form the intrinsic base through the same dielectric window in which the polysilicon emitter contact component is later created. Following poly deposition within the window and etch to create the polysilicon emitter contact component, large-angle tilt ion implantation is employed to form a link base between the intrinsic base and a subsequently-formed base contact region. Tilted implantation enables the link base region to extend underneath the edges of the polysilicon emitter contact component, creating a low resistance path between the intrinsic base and the extrinsic base. Fabrication of the device is much simplified over a conventional double-poly transistor, particularly if tilted implantation is already employed in the process flow to form an associated structure such as an LDMOS.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: July 17, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6225181
    Abstract: A bipolar transistor is vertically isolated from underlying silicon by an isolation layer of conductivity type opposite that of the collector. This isolation layer lies beneath the heavily doped buried layer portion of the collector, and is formed either by ion implantation prior to epitaxial growth of well regions, or by high energy ion implantation into the substrate prior to formation of the well and the heavily doped buried collector layer. Utilization of trench lateral isolation extending into the semiconductor material beyond the isolation layer permits blanket implant of the isolation layer, obviating the need for an additional masking step.
    Type: Grant
    Filed: April 19, 1999
    Date of Patent: May 1, 2001
    Assignee: National Semiconductor Corp.
    Inventor: Haydn James Gregory
  • Patent number: 6069034
    Abstract: A DMOS structure is formed with P-body and N-source implantations are self-aligned using the same photoresist mask. Following formation of field isolation structures and removal of the composite nitride, a `double-implantation` of P body and N source is made using a single resist masking stage. This process flow utilizes a relatively low N-source implantation dose, as N-source and P-body implantations are subsequently thermally diffused together (co-driven) using the original thermal budget of the P-body drive-in. The N-source implant thus now sees the same thermal budget as does the P-body implant. As a result in this process scheme, overetching of P-body and N-source during composite nitride removal is eliminated, while process simplicity is conserved. Moreover, channel overlap remains self-aligned by implanting N-source and P-body through the same mask. Differing rates of thermal diffusion of the P and N type dopant determine the extent of channel overlap.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: May 30, 2000
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory
  • Patent number: 6043130
    Abstract: A bipolar transistor compatible with CMOS processes utilizes only a single layer of polysilicon while maintaining the low base resistance associated with conventional double-polysilicon bipolar designs. Dopant is implanted to form the intrinsic base through the same dielectric window in which the polysilicon emitter contact component is later created. Following poly deposition within the window and etch to create the polysilicon emitter contact component, large-angle tilt ion implantation is employed to form a link base between the intrinsic base and a subsequently-formed base contact region. Tilted implantation enables the link base region to extend underneath the edges of the polysilicon emitter contact component, creating a low resistance path between the intrinsic base and the extrinsic base. Fabrication of the device is much simplified over a conventional double-poly transistor, particularly if tilted implantation is already employed in the process flow to form an associated structure such as an LDMOS.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: March 28, 2000
    Assignee: National Semiconductor Corporation
    Inventor: Haydn James Gregory