Patents by Inventor Steven Maxwell

Steven Maxwell 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: 10192927
    Abstract: A method for forming a resistive switching device. The method includes providing a substrate having a surface region and forming a first dielectric material overlying the surface region. A first wiring structure is formed overlying the first dielectric material. The method forms one or more first structure comprising a junction material overlying the first wiring structure. A second structure comprising a stack of material is formed overlying the first structure. The second structure includes a resistive switching material, an active conductive material overlying the resistive switching material, and a second wiring material overlying the active conductive material. The second structure is configured such that the resistive switching material is free from a coincident vertical sidewall region with the junction material.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: January 29, 2019
    Assignee: CROSSBAR, INC.
    Inventors: Mark Harold Clark, Natividad Vasquez, Steven Maxwell
  • Patent number: 9412790
    Abstract: A method for forming a resistive switching device. The method includes providing a substrate having a surface region and forming a first dielectric material overlying the surface region. A first wiring structure is formed overlying the first dielectric material. The method forms one or more first structure comprising a junction material overlying the first wiring structure. A second structure comprising a stack of material is formed overlying the first structure. The second structure includes a resistive switching material, an active conductive material overlying the resistive switching material, and a second wiring material overlying the active conductive material. The second structure is configured such that the resistive switching material is free from a coincident vertical sidewall region with the junction material.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: August 9, 2016
    Assignee: Crossbar, Inc.
    Inventors: Mark Harold Clark, Natividad Vasquez, Steven Maxwell
  • Patent number: 8981331
    Abstract: In some embodiments, a memory cell is provided that includes a metal-insulator-metal stack and a steering element coupled to the metal-insulator-metal stack. The metal-insulator-metal stack includes a first conductive layer, a reversible resistivity switching layer above the first conductive layer, and a second conductive layer above the reversible resistivity switching layer. The first conductive layer and/or the second conductive layer includes a first semiconductor material layer. The steering element includes the first semiconductor material layer. Numerous other aspects are provided.
    Type: Grant
    Filed: March 4, 2013
    Date of Patent: March 17, 2015
    Assignee: SanDisk 3D LLC
    Inventors: Yung-Tin Chen, Chuanbin Pan, Andrei Mihnea, Steven Maxwell, Kun Hou
  • Patent number: 8969845
    Abstract: A memory cell is provided that includes a steering element, a metal-insulator-metal stack coupled in series with the steering element, and a conductor above the metal-insulator-metal stack. The steering element includes a diode having an n-region and a p-region. The metal-insulator-metal stack includes a reversible resistivity-switching material between a top electrode and a bottom electrode, and the top electrode includes a highly doped semiconductor material. The memory cell does not include a metal layer disposed between the metal-insulator-metal stack and the conductor. The bottom electrode includes the n-region or the p-region of the diode, and the reversible resistivity-switching material is directly adjacent the n-region or the p-region of the diode. Numerous other aspects are provided.
    Type: Grant
    Filed: June 9, 2014
    Date of Patent: March 3, 2015
    Assignee: SanDisk 3D LLC
    Inventors: Yung-Tin Chen, Chuanbin Pan, Andrei Mihnea, Steven Maxwell, Kun Hou
  • Patent number: 8946667
    Abstract: A method for forming a resistive switching device. The method includes providing a substrate having a surface region and forming a first dielectric material overlying the surface region of the substrate. A first wiring structure overlies the first dielectric material. The method forms a first electrode material overlying the first wiring structure and a resistive switching material comprising overlying the first electrode material. An active metal material is formed overlying the resistive switching material. The active metal material is configured to form an active metal region in the resistive switching material upon application of a thermal energy characterized by a temperature no less than about 100 Degree Celsius. In a specific embodiment, the method forms a blocking material interposing the active metal material and the resistive switching material to inhibit formation of the active metal region in the resistive switching material during the subsequent processing steps.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: February 3, 2015
    Assignee: Crossbar, Inc.
    Inventors: Mark Harold Clark, Steven Maxwell, Harry Gee, Natividad Vasquez
  • Patent number: 8866124
    Abstract: In a first aspect, a vertical semiconductor diode is provided that includes (1) a first semiconductor layer formed above a substrate; (2) a second semiconductor layer formed above the first semiconductor layer; (3) a first native oxide layer formed above the first semiconductor layer; and (4) a third semiconductor layer formed above the first semiconductor layer, second semiconductor layer and first native oxide layer so as to form the vertical semiconductor diode that includes the first native oxide layer. Numerous other aspects are provided.
    Type: Grant
    Filed: February 2, 2011
    Date of Patent: October 21, 2014
    Assignee: SanDisk 3D LLC
    Inventors: Steven Maxwell, Abhijit Bandyopadhyay, Kun Hou, Er-Xuan Ping, Yung-Tin Chen, Li Xiao
  • Publication number: 20140284538
    Abstract: A memory cell is provided that includes a steering element, a metal-insulator-metal stack coupled in series with the steering element, and a conductor above the metal-insulator-metal stack. The steering element includes a diode having an n-region and a p-region. The metal-insulator-metal stack includes a reversible resistivity-switching material between a top electrode and a bottom electrode, and the top electrode includes a highly doped semiconductor material. The memory cell does not include a metal layer disposed between the metal-insulator-metal stack and the conductor. The bottom electrode includes the n-region or the p-region of the diode, and the reversible resistivity-switching material is directly adjacent the n-region or the p-region of the diode. Numerous other aspects are provided.
    Type: Application
    Filed: June 9, 2014
    Publication date: September 25, 2014
    Inventors: Yung-Tin Chen, Chuanbin Pan, Andrei Mihnea, Steven Maxwell, Kun Hou
  • Patent number: 8445385
    Abstract: Memory cells, and methods of forming such memory cells are provided that include a steering element coupled to a carbon-based reversible resistivity-switching material. In particular embodiments, methods in accordance with this invention etch a carbon nano-tube (“CNT”) film formed over a substrate, the methods including coating the substrate with a masking layer, patterning the masking layer, and etching the CNT film through the patterned masking layer using a non-oxygen based chemistry. Other aspects are also described.
    Type: Grant
    Filed: April 10, 2009
    Date of Patent: May 21, 2013
    Assignee: SanDisk 3D LLC
    Inventors: April D. Schricker, Andy Fu, Michael Konevecki, Steven Maxwell
  • Patent number: 8410582
    Abstract: A semiconductor p-i-n diode and method for forming the same are described herein. In one aspect, a SiGe region is formed between a region doped to have one conductivity (either p+ or n+) and an electrical contact to the p-i-n diode. The SiGe region may serve to lower the contact resistance, which may increase the forward bias current. The doped region extends below the SiGe region such that it is between the SiGe region and an intrinsic region of the diode. The p-i-n diode may be formed from silicon. The doped region below the SiGe region may serve to keep the reverse bias current from increasing as result of the added SiGe region. In one embodiment, the SiGe is formed such that the forward bias current of an up-pointing p-i-n diode in a memory array substantially matches the forward bias current of a down-pointing p-i-n diode which may achieve better switching results when these diodes are used with the R/W material in a 3D memory array.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: April 2, 2013
    Assignee: SanDisk 3D LLC
    Inventors: Abhijit Bandyopadhyay, Kun Hou, Steven Maxwell
  • Patent number: 8389375
    Abstract: In a first aspect, a method of forming a memory cell is provided, the method including: (1) forming a pillar above a substrate, the pillar comprising a steering element and a metal hardmask layer; (2) selectively removing the metal hardmask layer to create a void; and (3) forming a carbon-based switching material within the void. Numerous other aspects are provided.
    Type: Grant
    Filed: February 11, 2010
    Date of Patent: March 5, 2013
    Assignee: SanDisk 3D LLC
    Inventor: Steven Maxwell
  • Patent number: 8389971
    Abstract: In some embodiments, a memory cell is provided that includes a storage element formed from an MIM stack including (1) a first conductive layer; (2) an RRS layer formed above the first conductive layer; and (3) a second conductive layer formed above the RRS layer, at least one of the first and second conductive layers comprising a first semiconductor material layer. The memory cell includes a steering element coupled to the storage element, the steering element formed from the first semiconductor material layer of the MIM stack and one or more additional material layers. Numerous other aspects are provided.
    Type: Grant
    Filed: October 14, 2010
    Date of Patent: March 5, 2013
    Assignee: SanDisk 3D LLC
    Inventors: Yung-Tin Chen, Chuanbin Pan, Andrei Mihnea, Steven Maxwell, Kun Hou
  • Patent number: 8268678
    Abstract: A method of making a non-volatile memory device includes providing a substrate having a substrate surface, and forming a non-volatile memory array over the substrate surface. The non-volatile memory array includes an array of semiconductor diodes, and each semiconductor diode of the array of semiconductor diodes is disposed substantially parallel to the substrate surface.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: September 18, 2012
    Assignee: SanDisk 3D LLC
    Inventors: Steven Maxwell, Michael Konevecki, Mark H. Clark, Usha Raghuram
  • Publication number: 20120228579
    Abstract: A semiconductor p-i-n diode and method for forming the same are described herein. In one aspect, a SiGe region is formed between a region doped to have one conductivity (either p+ or n+) and an electrical contact to the p-i-n diode. The SiGe region may serve to lower the contact resistance, which may increase the forward bias current. The doped region extends below the SiGe region such that it is between the SiGe region and an intrinsic region of the diode. The p-i-n diode may be formed from silicon. The doped region below the SiGe region may serve to keep the reverse bias current from increasing as result of the added SiGe region. In one embodiment, the SiGe is formed such that the forward bias current of an up-pointing p-i-n diode in a memory array substantially matches the forward bias current of a down-pointing p-i-n diode which may achieve better switching results when these diodes are used with the R/W material in a 3D memory array.
    Type: Application
    Filed: May 23, 2012
    Publication date: September 13, 2012
    Inventors: Abhijit Bandyopadhyay, Kun Hou, Steven Maxwell
  • Publication number: 20120193756
    Abstract: In a first aspect, a vertical semiconductor diode is provided that includes (1) a first semiconductor layer formed above a substrate; (2) a second semiconductor layer formed above the first semiconductor layer; (3) a first native oxide layer formed above the first semiconductor layer; and (4) a third semiconductor layer formed above the first semiconductor layer, second semiconductor layer and first native oxide layer so as to form the vertical semiconductor diode that includes the first native oxide layer. Numerous other aspects are provided.
    Type: Application
    Filed: February 2, 2011
    Publication date: August 2, 2012
    Inventors: Steven Maxwell, Abhijit Bandyopadhyay, Kun Hou, Er-Xuan Ping, Yung-Tin Chen, Li Xiao
  • Patent number: 8207064
    Abstract: A semiconductor p-i-n diode and method for forming the same are described herein. In one aspect, a SiGe region is formed between a region doped to have one conductivity (either p+ or n+) and an electrical contact to the p-i-n diode. The SiGe region may serve to lower the contact resistance, which may increase the forward bias current. The doped region extends below the SiGe region such that it is between the SiGe region and an intrinsic region of the diode. The p-i-n diode may be formed from silicon. The doped region below the SiGe region may serve to keep the reverse bias current from increasing as result of the added SiGe region. In one embodiment, the SiGe is formed such that the forward bias current of an up-pointing p-i-n diode in a memory array substantially matches the forward bias current of a down-pointing p-i-n diode which may achieve better switching results when these diodes are used with the R/W material in a 3D memory array.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: June 26, 2012
    Assignee: SanDisk 3D LLC
    Inventors: Abhijit Bandyopadhyay, Kun Hou, Steven Maxwell
  • Patent number: 8183121
    Abstract: Methods in accordance with aspects of this invention form microelectronic structures in accordance with other aspects this invention, such as non-volatile memories, that include (1) a bottom electrode, (2) a resistivity-switchable layer disposed above and in contact with the bottom electrode, and (3) a top electrode disposed above and in contact with the resistivity-switchable layer; wherein the resistivity-switchable layer includes a carbon-based material and a dielectric filler material. Numerous additional aspects are provided.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: May 22, 2012
    Assignee: SanDisk 3D LLC
    Inventors: April D. Schricker, Steven Maxwell
  • Publication number: 20120091418
    Abstract: In some embodiments, a memory cell is provided that includes (1) a bipolar storage element formed from a metal-insulator-metal (MIM) stack including (a) a first conductive layer; (b) a reversible resistivity switching (RRS) layer formed above the first conductive layer; (c) a metal/metal oxide layer stack formed above the first conductive layer; and (d) a second conductive layer formed above the RRS layer and the metal/metal oxide layer stack; and (2) a steering element coupled to the storage element. Numerous other aspects are provided.
    Type: Application
    Filed: October 14, 2010
    Publication date: April 19, 2012
    Inventors: Yung-Tin Chen, Franz Kreupl, Steven Maxwell, Kun Hou
  • Patent number: 8076056
    Abstract: A method of making a device includes forming an underlying mask layer over an underlying layer, forming a first mask layer over the underlying mask layer, patterning the first mask layer to form first mask features, undercutting the underlying mask layer to form underlying mask features using the first mask features as a mask, removing the first mask features, and patterning the underlying layer using at least the underlying mask features as a mask.
    Type: Grant
    Filed: October 6, 2008
    Date of Patent: December 13, 2011
    Assignee: SanDisk 3D LLC
    Inventors: Chun-Ming Wang, Steven Maxwell, Paul Wai Kie Poon, Yung-Tin Chen
  • Publication number: 20110193042
    Abstract: In a first aspect, a method of forming a memory cell is provided, the method including: (1) forming a pillar above a substrate, the pillar comprising a steering element and a metal hardmask layer; (2) selectively removing the metal hardmask layer to create a void; and (3) forming a carbon-based switching material within the void. Numerous other aspects are provided.
    Type: Application
    Filed: February 11, 2010
    Publication date: August 11, 2011
    Inventor: Steven Maxwell
  • Patent number: 7927977
    Abstract: A method of making a semiconductor device includes forming a first layer comprising a seed material over an underlying layer, forming a second layer comprising a sacrificial material over the first layer, the sacrificial material being different from the seed material, patterning the first layer and the second layer into a plurality of separate features, forming an insulating filling material between the plurality of the separate features, removing the sacrificial material from the separate features to form a plurality of openings in the insulating filling material such that the seed material is exposed in the plurality of openings, and growing a semiconductor material on the exposed seed material in the plurality of openings.
    Type: Grant
    Filed: July 15, 2009
    Date of Patent: April 19, 2011
    Assignee: SanDisk 3D LLC
    Inventors: Raghuveer S. Makala, Vance Dunton, Yoichiro Tanaka, Steven Maxwell, Tong Zhang, Steven J. Radigan