Patents by Inventor Craig Swift

Craig 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).

  • Publication number: 20070238249
    Abstract: A semiconductor storage cell includes a first source/drain region underlying a first trench defined in a semiconductor layer. A second source/drain region underlies a second trench in the semiconductor layer. A first select gate in the first trench and a second select gate in the second trench are lined by a select gate dielectric. A charge storage stack overlies the select gates and a control gate overlies the stack. The DSEs may comprise discreet accumulations of polysilicon. An upper surface of the first and second select gates is lower than an upper surface of the first and second trenches. The control gate may be a continuous control gate traversing and running perpendicular to the select gates. The cell may include contacts to the semiconductor layer. The control gate may include a first control gate overlying the first select gate and a second control gate overlying the second select gate.
    Type: Application
    Filed: March 30, 2006
    Publication date: October 11, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore, Paul Ingersoll
  • Publication number: 20070176223
    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: Application
    Filed: January 27, 2006
    Publication date: August 2, 2007
    Inventors: Gowrishankar Chindalore, Craig Swift
  • Publication number: 20070176226
    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: Application
    Filed: January 27, 2006
    Publication date: August 2, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore
  • Publication number: 20070177440
    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: Application
    Filed: January 27, 2006
    Publication date: August 2, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore
  • Publication number: 20070178649
    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: Application
    Filed: January 27, 2006
    Publication date: August 2, 2007
    Inventors: Craig Swift, Thuy Dao, Michael Sadd
  • Publication number: 20070134888
    Abstract: A method of making a semiconductor device includes providing a first wafer and providing a second wafer having a first side and a second side, the second wafer including a semiconductor substrate, a storage layer, and a layer of gate material. The storage layer may be located between the semiconductor structure and the layer of the gate material and the storage layer may be located closer to the first side of the second wafer than the semiconductor structure. The method further includes boding the first side of the second wafer to the first wafer. The method further includes removing a first portion of the semiconductor structure to leave a layer of the semiconductor structure after the bonding. The method further includes forming a transistor having a channel region, wherein at least a portion of the channel region is formed from the layer of the semiconductor structure.
    Type: Application
    Filed: December 14, 2005
    Publication date: June 14, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore, Thuy Dao, Michael Sadd
  • Publication number: 20070117319
    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: Application
    Filed: January 24, 2007
    Publication date: May 24, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar Chindalore, Craig Swift
  • Publication number: 20070018234
    Abstract: An electronic device can include memory cells that are connected to gate lines, bit lines, or a combination thereof. In one embodiment, at least two sets of memory cells can be oriented substantially along a first direction, (e.g., rows or columns). A first gate line may be electrically connected to fewer rows or columns of memory cells as compared to a second gate line. For example, the first gate line may only be electrically connected to the first set of memory cells, and the second gate line may be electrically connected to the second and third sets of memory cells. In another embodiment, a first bit line may be electrically connected to fewer rows or columns of memory cells as compared to a second bit line. In still another embodiment, another set of memory cells may be oriented substantially along another direction that is substantially perpendicular to the first direction.
    Type: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar Chindalore, Paul Ingersoll, Craig Swift
  • Publication number: 20070020845
    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: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore
  • Publication number: 20070020856
    Abstract: forming a first gate electrode within the trench after forming the discontinuous storage elements. At least one discontinuous storage element lies along the wall of the trench at an elevation between an upper surface of the first gate electrode and a primary surface of the substrate. The process can also include forming a second gate electrode overlying 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: Michael Sadd, Ko-Min Chang, Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Publication number: 20070018232
    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: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Inventors: Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Publication number: 20070020831
    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: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Inventors: Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Publication number: 20070018222
    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: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Michael Sadd, Ko-Min Chang, Gowrishankar Chindalore, Cheong Hong, Craig Swift
  • Publication number: 20070018221
    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: Application
    Filed: July 25, 2005
    Publication date: January 25, 2007
    Inventors: Craig Swift, Gowrishankar Chindalore
  • Publication number: 20070018216
    Abstract: An electronic device can include discontinuous storage elements that lie within a trench. The electronic device can include a substrate including a trench that includes a wall and a bottom and extends from a primary surface of the substrate. The electronic device can also include discontinuous storage elements, wherein a portion of the discontinuous storage elements lies at least within the trench. The electronic device can further include a first gate electrode, wherein at least a part of the portion of the discontinuous storage elements lies between the first gate electrode and the wall of the trench. The electronic device can still further include a second gate electrode overlying 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 Chindalore, Paul Ingersoll, Craig Swift
  • Publication number: 20060076609
    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: Application
    Filed: March 14, 2005
    Publication date: April 13, 2006
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar Chindalore, Craig Swift
  • Publication number: 20060076586
    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: October 8, 2004
    Publication date: April 13, 2006
    Inventors: Craig Swift, Gowrishankar Chindalore, Laureen Parker
  • Publication number: 20060063327
    Abstract: A floating gate memory cell has a floating gate in which there are two adjacent floating gate layers. The top layer is made to have a contour while leaving the lower layer substantially unchanged. An interlevel dielectric and a control gate follow the contour of the floating gate to increase capacitance between the control gate and the floating gate. The two layers of the floating gate can be polysilicon in which the top layer has the contour formed therein by use of a sacrificial layer. The sacrificial layer is formed over the bottom polysilicon layer and etched. The top polysilicon layer is formed over the sacrificial layer. Subsequent processing of the top polysilicon layer exposes the remaining portion of the sacrificial layer so it can be removed; leaving the contour in the top polysilicon layer for the interlevel dielectric and the control gate.
    Type: Application
    Filed: September 17, 2004
    Publication date: March 23, 2006
    Inventors: Craig Swift, Gowrishankar Chindalore
  • Publication number: 20060063328
    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: Application
    Filed: September 17, 2004
    Publication date: March 23, 2006
    Inventors: Gowrishankar Chindalore, Craig Swift
  • Publication number: 20060046406
    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: Application
    Filed: August 31, 2004
    Publication date: March 2, 2006
    Inventors: Gowrishankar Chindalore, James Burnett, Craig Swift, Ramachandran Muralidhar