Patents by Inventor Craig T. Swift

Craig T. Swift 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: 7582929
    Abstract: An electronic device can include discontinuous storage elements that lie within a trench. In one embodiment, the electronic device can include a substrate having a trench that includes a wall and a bottom. The electronic device can also include a portion of discontinuous storage elements that lie within the trench. The electronic device can also include a first gate electrode, wherein at least one discontinuous storage element lies along the wall of the trench at an elevation between and upper surface of the first gate electrode and a primary surface of the substrate. The electronic device can also include a second gate electrode overlying the first gate electrode and the primary surface of the substrate. In another embodiment, a conductive line can be electrically connected to one or more rows or columns of memory cells, and another conductive line can be more rows or more columns of memory cells.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: September 1, 2009
    Assignee: Freescale Semiconductor, Inc
    Inventors: Michael A. Sadd, Ko-Min Chang, Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Patent number: 7563681
    Abstract: A method for making a semiconductor device comprises providing a first wafer and providing a second wafer having a first side and a second side, the second wafer including a semiconductor structure, a first storage layer, and a layer of gate material, wherein the first storage layer is located between the semiconductor structure and the layer of gate material and closer to the first side of the second wafer than the semiconductor structure. The method further includes bonding the first side of the second wafer to the first wafer and cleaving away a first portion of the semiconductor structure to leave a layer of the semiconductor structure after the bonding. The method further includes forming a second storage layer over the layer of the semiconductor structure and forming a top gate over the second storage layer.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: July 21, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Thuy B. Dao, Michael A. Sadd
  • Publication number: 20090170262
    Abstract: A virtual ground memory array (VGA) is formed by a storage layer over a substrate with a conductive layer over the storage layer. The conductive layer is opened according to a patterned photoresist layer. The openings are implanted to form source/drain lines in the substrate, then filled with a layer of dielectric material. Chemical mechanical polishing (CMP) is then performed until the top of the conductive layer is exposed. This leaves dielectric spacers over the source/drain lines and conductive material between the dielectric spacers. Word lines are then formed over the conductive material and the dielectric spacers. As an alternative, instead of using a conductive layer, a sacrificial layer is used that is removed after the CMP step. After removing the sacrificial portions, the word lines are formed. In both cases, dielectric spacers reduce gate/drain capacitance and the distance from substrate to gate is held constant across the channel.
    Type: Application
    Filed: March 4, 2009
    Publication date: July 2, 2009
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore, Laureen H. Parker
  • Patent number: 7544980
    Abstract: A memory cell is implemented using a semiconductor fin in which the channel region is along a sidewall of the fin between source and drains regions. One portion of the channel region has a select gate adjacent to it and another other portion has the control gate adjacent to it with a charge storage structure there between. In some embodiments, independent control gate structures are located adjacent opposite sidewalls of the fin so as to implement two memory cells.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: June 9, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Craig T. Swift
  • Patent number: 7518179
    Abstract: A virtual ground memory array (VGA) is formed by a storage layer over a substrate with a conductive layer over the storage layer. The conductive layer is opened according to a patterned photoresist layer. The openings are implanted to form source/drain lines in the substrate, then filled with a layer of dielectric material. Chemical mechanical polishing (CMP) is then performed until the top of the conductive layer is exposed. This leaves dielectric spacers over the source/drain lines and conductive material between the dielectric spacers. Word lines are then formed over the conductive material and the dielectric spacers. As an alternative, instead of using a conductive layer, a sacrificial layer is used that is removed after the CMP step. After removing the sacrificial portions, the word lines are formed. In both cases, dielectric spacers reduce gate/drain capacitance and the distance from substrate to gate is held constant across the channel.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: April 14, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore, Laureen H. Parker
  • Publication number: 20080248649
    Abstract: A method and apparatus are described for forming a first inter-layer dielectric (ILD0) stack having a protective gettering layer (72) with a substantially uniform thickness. After forming device components (32, 33) on a substrate (31), a gap fill dielectric layer of SATEOS (52) is deposited over an etch stop layer of PEN ESL (42) and then planarized before sequentially depositing a gettering layer of BPTEOS (72) and capping dielectric layer (82) on the planarized gap fill dielectric layer (52). Once the ILD0 stack is formed, one or more contact openings (92, 94, 96) are etched through the ILD0 stack, thereby exposing the etch stop layer (42) over the intended contact regions.
    Type: Application
    Filed: April 5, 2007
    Publication date: October 9, 2008
    Inventors: Olubunmi O. Adetutu, Christopher B. Hundley, Paul A. Ingersoll, Craig T. Swift
  • Patent number: 7399675
    Abstract: An electronic device can include an NVM array, wherein portions of word lines are formed within trenches. Insulating features are formed over heavily doped regions within the substrate. In one embodiment, charge storage stacks and a control gate electrode layer can be formed and substantially fill the trench. The insulating features help to reduce capacitive coupling between the heavily doped regions and the control gate electrode layer. In a particular embodiment, the insulating features are recessed from a top surface of a layer outside the trenches. The control gate electrode layer can form a substantially continuous electrical path along the lengths of the word lines. This particular embodiment substantially eliminates the formation of stringers or other residual etching artifacts from the control gate electrode layer within the array. A process can be performed to form the electronic device.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: July 15, 2008
    Assignee: Freescale Semiconductor, Inc
    Inventors: Gowrishankar L. Chindalore, Craig T. Swift
  • Patent number: 7394686
    Abstract: A semiconductor storage cell includes first and second source/drain regions underlying first and second trenches defined in a semiconductor substrate. Sidewalls of the trenches are lined with a charge storage stack that includes a layer of discontinuous storage elements (DSEs), which are preferably silicon nanocrystals. Spacer control gates are located in the trenches adjacent to the charge storage stacks on the trench sidewalls. The trench depth exceeds the spacer height so that a gap exists between a top of the spacers and the top of the substrate. A continuous select gate layer overlies the first trench. The gap facilitates ballistic programming of the DSEs adjacent to the gap by accelerating electrons traveling substantially perpendicular to the trench sidewalls. The storage cell may employ hot carrier injection programming to program a portion of the DSEs proximal to the source/drain regions.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: July 1, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore
  • Patent number: 7391659
    Abstract: A memory cell is programmed by injecting charge into a charge storage layer of the memory cell. A desired programmed charge results in the charge storage layer over an edge portion of a channel region of the memory cell. An undesired programmed charge results in the charge storage layer over an inner portion of the channel region. Charge tunneling is used to substantially remove the undesired programmed charge in the charge storage layer. In one form the memory cell has a substrate having a channel region, a first dielectric layer over the substrate and a charge storage layer over the first dielectric layer. A second dielectric layer over the charge storage layer has a first portion that is thicker than a second portion to selectively control the charge tunneling.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: June 24, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore
  • Patent number: 7317222
    Abstract: A memory cell is programmed by injecting charge into a charge storage layer of the memory cell. A desired programmed charge results in the charge storage layer over an edge portion of a channel region of the memory cell. An undesired programmed charge results in the charge storage layer over an inner portion of the channel region. Charge tunneling is used to substantially remove the undesired programmed charge in the charge storage layer. In one form the memory cell has a substrate having a channel region, a first dielectric layer over the substrate and a charge storage layer over the first dielectric layer. A second dielectric layer over the charge storage layer has a first portion that is thicker than a second portion to selectively control the charge tunneling.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: January 8, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore
  • Patent number: 7314798
    Abstract: A method of making an array of storage cells includes a first source/drain region underlying a first trench defined in a semiconductor substrate and a second source/drain region underlying a second trench in the substrate. A charge storage stack lines each of the trenches where the charge storage stack includes a layer of discontinuous storage elements (DSEs). A control gate overlies the first trench. The control gate may run perpendicular to the trenches and traverse the first and second trenches. In another implementation, the control gate runs parallel with the trenches. The storage cell may include one or more diffusion regions occupying an upper surface of the substrate between the first and second trenches. The diffusion region may reside between first and second control gates that are parallel to the trenches. Alternatively, a pair of diffusion regions may occur on either side of a control gate that is perpendicular to the trenches.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: January 1, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Patent number: 7285819
    Abstract: An array of storage cells include a first source/drain region underlying a first trench defined in a semiconductor substrate and a second source/drain region underlying a second trench in the substrate. A charge storage stack lines each of the trenches where the charge storage stack includes a layer of discontinuous storage elements (DSEs). A control gate overlies the first trench. The control gate may run perpendicular to the trenches and traverse the first and second trenches. In another implementation, the control gate runs parallel with the trenches. The storage cell may include one or more diffusion regions occupying an upper surface of the substrate between the first and second trenches. The diffusion region may reside between first and second control gates that are parallel to the trenches. Alternatively, a pair of diffusion regions may occur on either side of a control gate that is perpendicular to the trenches.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: October 23, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Patent number: 7250340
    Abstract: A method of fabricating a semiconductor storage cell that includes first and second source/drain regions underlying first and second trenches defined in a semiconductor substrate. Sidewalls of the trenches are lined with a charge storage stack that includes a layer of discontinuous storage elements (DSEs), which are preferably silicon nanocrystals. Spacer control gates are located in the trenches adjacent to the charge storage stacks on the trench sidewalls. The trench depth exceeds the spacer height so that a gap exists between a top of the spacers and the top of the substrate. A continuous select gate layer overlies the first trench. The gap facilitates ballistic programming of the DSEs adjacent to the gap by accelerating electrons traveling substantially perpendicular to the trench sidewalls. The storage cell may employ hot carrier injection programming to program a portion of the DSEs proximal to the source/drain regions.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: July 31, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Craig T. Swift, Gowrishankar L. Chindalore
  • Patent number: 7226840
    Abstract: A process for forming an electronic device can include forming a first set of discontinuous storage elements over a primary surface of a substrate and forming a trench within the substrate. The process can also include forming a second set of discontinuous storage elements within the trench. The process can further include forming a first gate electrode within the trench, wherein a discontinuous storage element lies between the first gate electrode and a wall of the trench. The process can still further include removing a part of the second set of discontinuous storage elements and forming a second gate electrode over the first gate electrode. After forming the second gate electrode, substantially none of the second set of discontinuous storage elements lies along the wall of the trench at an elevation between an upper surface of the first gate electrode and the primary surface of the substrate.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: June 5, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Patent number: 7205608
    Abstract: An electronic device can include a substrate having a trench that includes a wall and a bottom. The electronic device can also include a first set of discontinuous storage elements that overlie a primary surface of the substrate and a second set of discontinuous storage elements that lie within the trench. The electronic device can also include a first gate electrode, wherein substantially none of the discontinuous storage elements lies along the wall of the trench at an elevation between and upper surface of the first gate electrode and the primary surface of the substrate. The electronic device can also include a second gate electrode overlying the first gate electrode and the primary surface. In another embodiment, a conductive line can be electrically connected to one or more rows or columns of memory cells, and another conductive line can be more rows or more columns of memory cells.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: April 17, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Patent number: 7195983
    Abstract: A non-volatile memory (NVM) has a silicon germanium (SiGe) drain and a silicon carbon (SiC) source. The source being SiC provides for a stress on the channel that improves N channel mobility. The SiC also has a larger bandgap than the substrate, which is silicon. This results in it being more difficult to generate electron/hole pairs by impact ionization. Thus, it can be advantageous to use the SiC region for the drain during a read. The SiGe is used as the drain for programming and erase. The SiGe, having a smaller bandgap than the silicon substrate results in improved programming by generating electron/hole pairs by impact ionization and improved erasing by generating electron hole/pairs by band-to-band tunneling, both at lower voltage levels.
    Type: Grant
    Filed: August 31, 2004
    Date of Patent: March 27, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, James David Burnett, Craig T. Swift, Ramachandran Muralidhar
  • Patent number: 7183161
    Abstract: A floating gate memory cell has a floating gate in which there are two floating gate layers. The top layer is etched to provide a contour in the top layer while leaving the lower layer unchanged. The control gate follows the contour of the floating gate to increase capacitance therebetween. The two layers of the floating gate can be polysilicon separated by a very thin etch stop layer. This etch stop layer is thick enough to provide an etch stop during a polysilicon etch but preferably thin enough to be electrically transparent. Electrons are able to easily move between the two layers. Thus the etch of the top layer does not extend into the lower layer but the first and second layer have the electrical effect for the purposes of a floating gate of being a continuous conductive layer.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: February 27, 2007
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Craig T. Swift
  • Publication number: 20070020820
    Abstract: A process for forming an electronic device can include forming a first set of discontinuous storage elements over a primary surface of a substrate and forming a trench within the substrate. The process can also include forming a second set of discontinuous storage elements within the trench. The process can further include forming a first gate electrode within the trench, wherein a discontinuous storage element lies between the first gate electrode and a wall of the trench. The process can still further include removing a part of the second set of discontinuous storage elements and forming a second gate electrode over the first gate electrode. After forming the second gate electrode, substantially none of the second set of discontinuous storage elements lies along the wall of the trench at an elevation between an upper surface of the first gate electrode and the primary surface of the substrate.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift
  • Publication number: 20070020857
    Abstract: A process for forming an electronic device can include forming a first trench within a substrate, wherein the trench includes a wall and a bottom and extends from a primary surface of the substrate. The process can also include forming discontinuous storage elements and forming a first gate electrode within the trench such that, a first discontinuous storage element of the discontinuous storage elements lies between the first gate electrode and the wall of the trench. The process can further include removing the discontinuous storage elements that overlie the primary surface of the substrate. The process can still further include forming a second gate electrode that overlies the first gate electrode and the primary surface of the substrate.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Paul A. Ingersoll, Craig T. Swift
  • Publication number: 20070018240
    Abstract: An electronic device can include a substrate having a trench that includes a wall and a bottom. The electronic device can also include a first set of discontinuous storage elements that overlie a primary surface of the substrate and a second set of discontinuous storage elements that lie within the trench. The electronic device can also include a first gate electrode, wherein substantially none of the discontinuous storage elements lies along the wall of the trench at an elevation between and upper surface of the first gate electrode and the primary surface of the substrate. The electronic device can also include a second gate electrode overlying the first gate electrode and the primary surface. In another embodiment, a conductive line can be electrically connected to one or more rows or columns of memory cells, and another conductive line can be more rows or more columns of memory cells.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Cheong M. Hong, Craig T. Swift