Patents by Inventor Johann Alsmeier

Johann Alsmeier 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: 9780112
    Abstract: A method of fabricating a monolithic three dimensional memory structure is provided. The method includes forming a stack of alternating word line and dielectric layers above a substrate, forming a source line above the substrate, forming a memory hole extending through the alternating word line and dielectric layers and the source line, and forming a mechanical support element on the substrate adjacent to the memory hole.
    Type: Grant
    Filed: October 26, 2015
    Date of Patent: October 3, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Jin Liu, Chun Ge, Johann Alsmeier
  • Patent number: 9780182
    Abstract: A memory film and a semiconductor channel can be formed within each memory opening that extends through a stack including an alternating plurality of insulator layers and sacrificial material layers. After formation of backside recesses through removal of the sacrificial material layers selective to the insulator layers, a metallic barrier material portion can be formed in each backside recess. A molybdenum-containing portion can be formed in each backside recess. Each backside recess can be filled with a molybdenum-containing portion alone, or can be filled with a combination of a molybdenum-containing portion and a metallic material portion including a material other than molybdenum.
    Type: Grant
    Filed: June 26, 2015
    Date of Patent: October 3, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Somesh Peri, Raghuveer S. Makala, Sateesh Koka, Yao-Sheng Lee, Johann Alsmeier, George Matamis
  • Patent number: 9780108
    Abstract: An alternating stack of insulating layers and sacrificial material layers is formed over a substrate. Memory openings are formed through the alternating stack to the substrate. After formation of memory film layers, a sacrificial cover material layer can be employed to protect the tunneling dielectric layer during formation of a bottom opening in the memory film layers. An amorphous semiconductor material layer can be deposited and optionally annealed in an ambient including argon and/or deuterium to form a semiconductor channel layer having a thickness less than 5 nm and surface roughness less than 10% of the thickness. Alternately or additionally, at least one interfacial layer can be employed on either side of the amorphous semiconductor material layer to reduce surface roughness of the semiconductor channel. The ultrathin channel can have enhanced mobility due to quantum confinement effects.
    Type: Grant
    Filed: October 19, 2015
    Date of Patent: October 3, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Peter Rabkin, Jayavel Pachamuthu, Masaaki Higashitani, Johann Alsmeier
  • Publication number: 20170278571
    Abstract: Two vertical NAND strings can share a common bit line by providing two pairs of drain select transistors. Channels of each vertical NAND string containing an adjoining pair of drain select transistors are incorporated into a respective vertical semiconductor channel, which is adjoined to a respective drain region which is connected to the common bit line. The drain select transistors have mismatched threshold voltages at each level such that each vertical NAND string includes a level at which a respective drain select transistor has a higher threshold voltage than a counterpart drain select transistor for the other vertical NAND string at the same level. By turning on three drain select transistors out of four, only one vertical NAND string can be activated while the common bit line is biased at a suitable bias voltage. A programming operation or a read operation can be performed only on the activated NAND string.
    Type: Application
    Filed: March 23, 2016
    Publication date: September 28, 2017
    Inventors: Murshed Chowdhury, Jin Liu, Yanli Zhang, Andrew Lin, Raghuveer S. Makala, Johann Alsmeier
  • Patent number: 9761604
    Abstract: Disclosed herein is 3D memory with vertical NAND strings having a III-V compound channel, as well as methods of fabrication. The III-V compound has at least one group III element and at least one group V element. The III-V compound provides for high electron mobility transistor cells. Note that III-V materials may have a much higher electron mobility compared to silicon. Thus, much higher cell current and overall cell performance can be achieved. Also, the memory device may have better read-write efficiency due to much higher carrier mobility and velocity. The tunnel dielectric of the memory cells may have an Al2O3 film in direct contact with the III-V NAND channel. The drain end of the NAND channel may be a metal-III-V alloy in direct contact with a metal region. The body of the source side select transistor could be formed from the III-V compound or from crystalline silicon.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: September 12, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Peter Rabkin, Jayavel Pachamuthu, Johann Alsmeier, Masaaki Higashitani
  • Patent number: 9754667
    Abstract: A three-dimensional NAND stacked non-volatile memory array and a DRAM memory array are provided. The three-dimensional NAND stacked non-volatile memory array and the DRAM memory array are integrated on a single substrate.
    Type: Grant
    Filed: November 6, 2015
    Date of Patent: September 5, 2017
    Assignee: SanDisk Technologies LLC
    Inventor: Johann Alsmeier
  • Patent number: 9748267
    Abstract: A NAND memory cell region of a NAND device includes a conductive source line that extends substantially parallel to a major surface of a substrate, a first semiconductor channel that extends substantially perpendicular to a major surface of the substrate, and a second semiconductor channel that extends substantially perpendicular to the major surface of the substrate. At least one of a bottom portion and a side portion of the first semiconductor channel contacts the conductive source line and at least one of a bottom portion and a side portion of the second semiconductor channel contacts the conductive source line.
    Type: Grant
    Filed: September 2, 2016
    Date of Patent: August 29, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanli Zhang, Go Shoji, Johann Alsmeier, Jayavel Pachamuthu, Yingda Dong, Jiahui Yuan
  • Publication number: 20170243879
    Abstract: Discrete silicon nitride portions can be formed at each level of electrically conductive layers in an alternating stack of insulating layers and the electrically conductive layers. The discrete silicon nitride portions can be employed as charge trapping material portions, each of which is laterally contacted by a tunneling dielectric portion on the front side, and by a blocking dielectric portion on the back side. The tunneling dielectric portions may be formed as discrete material portions or portions within a tunneling dielectric layer. The blocking dielectric portions may be formed as discrete material portions or portions within a blocking dielectric layer. The discrete silicon nitride portions can be formed by depositing a charge trapping material layer and selectively removing portions of the charge trapping material layer at levels of the insulating layers. Various schemes may be employed to singulate the charge trapping material layer.
    Type: Application
    Filed: February 22, 2016
    Publication date: August 24, 2017
    Inventors: Jixin YU, Zhenyu LU, Daxin MAO, Yanli ZHANG, Andrey SEROV, Chun GE, Johann ALSMEIER
  • Publication number: 20170236746
    Abstract: Contacts to peripheral devices extending through multiple tier structures of a three-dimensional memory device can be formed with minimal additional processing steps. First peripheral via cavities through a first tier structure can be formed concurrently with formation of first memory openings. Sacrificial via fill structures can be formed in the first peripheral via cavities concurrently with formation of sacrificial memory opening fill structures that are formed in the first memory openings. Second peripheral via cavities through a second tier structure can be formed concurrently with formation of word line contact via cavities that extend to top surfaces of electrically conductive layers in the first and second tier structures. After removal of the sacrificial via fill structures, the first and second peripheral via cavities can be filled with a conductive material to form peripheral contact via structures concurrently with formation of word line contact via structures.
    Type: Application
    Filed: September 23, 2016
    Publication date: August 17, 2017
    Inventors: Jixin YU, Zhenyu LU, Hiroyuki OGAWA, Daxin MAO, Kensuke YAMAGUCHI, Sung Tae LEE, Yao-sheng LEE, Johann ALSMEIER
  • Publication number: 20170236896
    Abstract: A method of dividing drain select gate electrodes in a three-dimensional vertical memory device is provided. An alternating stack of insulating layers and spacer material layers is formed over a substrate. A first insulating cap layer is formed over the alternating stack. A plurality of memory stack structures is formed through the alternating stack and the first insulating cap layer. The first insulating cap layer is vertically recessed, and a conformal material layer is formed over protruding portions of the memory stack structures. Spacer portions are formed by an anisotropic etch of the conformal material layer such that the sidewalls of the spacer portions having protruding portions. A self-aligned separator trench with non-uniform sidewalls having protruding portions is formed through an upper portion of the alternating stack by etching the upper portions of the alternating stack between the spacer portions.
    Type: Application
    Filed: May 16, 2016
    Publication date: August 17, 2017
    Inventors: Zhenyu LU, Kota FUNAYAMA, Chun-Ming WANG, Jixin YU, Chenche HUANG, Tong ZHANG, Daxin MAO, Johann ALSMEIER, Makoto YOSHIDA, Lauren MATSUMOTO
  • Publication number: 20170229472
    Abstract: A memory opening can be formed through a multiple tier structure. Each tier structure includes an alternating stack of sacrificial material layers and insulating layers. After formation of a dielectric oxide layer, the memory opening is filled with a sacrificial memory opening fill structure. The sacrificial material layers are removed selective to the insulating layers and the dielectric oxide layer to form backside recesses. Physically exposed portions of the dielectric oxide layer are removed. A backside blocking dielectric and electrically conductive layers are formed in the backside recesses.
    Type: Application
    Filed: February 4, 2016
    Publication date: August 10, 2017
    Inventors: Ching-Huang LU, Zhenyu LU, Jixin YU, Daxin MAO, Johann ALSMEIER, Wenguang Stephen SHI, Henry CHIEN
  • Patent number: 9728551
    Abstract: A memory opening can be formed through a multiple tier structure. Each tier structure includes an alternating stack of sacrificial material layers and insulating layers. After formation of a dielectric oxide layer, the memory opening is filled with a sacrificial memory opening fill structure. The sacrificial material layers are removed selective to the insulating layers and the dielectric oxide layer to form backside recesses. Physically exposed portions of the dielectric oxide layer are removed. A backside blocking dielectric and electrically conductive layers are formed in the backside recesses. Subsequently, the sacrificial memory opening fill structure is replaced with a memory stack structure including a plurality of charge storage regions and a semiconductor channel. Hydrogen or deuterium from a dielectric core may then be outdiffused into the semiconductor channel.
    Type: Grant
    Filed: February 4, 2016
    Date of Patent: August 8, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ching-Huang Lu, Zhenyu Lu, Jixin Yu, Daxin Mao, Johann Alsmeier, Wenguang Stephen Shi, Henry Chien
  • Patent number: 9728546
    Abstract: A three dimensional NAND device includes a common vertical channel and electrically isolated control gate electrodes on different lateral sides of the channel in each device level to form different lateral portions of a memory cell in each device level. Dielectric separator structures are located between and electrically isolate the control gate electrodes. The lateral portions of the memory cell in each device level may be electrically isolated by at least one of doping ungated portions of the channel adjacent to the separator structures or storing electrons in the separator structure.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: August 8, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Andrey Serov, James K. Kai, Yanli Zhang, Henry Chien, Johann Alsmeier
  • Patent number: 9716101
    Abstract: Techniques for forming 3D memory arrays are disclosed. Memory openings are filled with a sacrificial material, such as silicon or nitride. Afterwards, a replacement technique is used to remove nitride from an ONON stack and replace it with a conductive material such as tungsten. Afterwards, memory cell films are formed in the memory openings. The conductive material serves as control gates of the memory cells. The control gate will not suffer from corner rounding. ONON shrinkage is avoided, which will prevent control gate shrinkage. Block oxide between the charge storage region and control gate may be deposited after control gate replacement, so the uniformity is good. Block oxide may be deposited after control gate replacement, so TiN adjacent to control gates can be thicker to prevent fluorine attacking the insulator between adjacent control gates. Therefore, control gate to control gate shorting is prevented.
    Type: Grant
    Filed: October 30, 2015
    Date of Patent: July 25, 2017
    Assignee: SanDisk Technologies LLC
    Inventors: Zhenyu Lu, Hiro Kinoshita, Daxin Mao, Johann Alsmeier, Wenguang Shi, Yingda Dong, Henry Chien, Kensuke Yamaguchi, Xiaolong Hu
  • Patent number: 9698153
    Abstract: Alignment between memory openings through multiple tier structures can be facilitated employing a temporary landing pad. The temporary landing pad can have a greater area than the horizontal cross-sectional area of a first memory opening through a first tier structure including a first alternating stack of first insulating layers and first spacer material layers. An upper portion of a first memory film is removed, and a sidewall of an insulating cap layer that defines the first memory opening can be laterally recessed to form a recessed cavity. A sacrificial fill material is deposited in the recessed cavity to form a sacrificial fill material portion, which functions as the temporary landing pad for a second memory opening that is subsequently formed through a second tier structure including second insulating layers and second spacer material layers. A memory stack structure can be formed through the first and second tier structures.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: July 4, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Jin Liu, Yanli Zhang, Murshed Chowdhury, Raghuveer S. Makala, Johann Alsmeier
  • Patent number: 9698152
    Abstract: A contact via structure can include a ruthenium portion formed by selective deposition of ruthenium on a semiconductor surface at the bottom of a contact trench. The ruthenium-containing portion can reduce contact resistance at the interface with an underlying doped semiconductor region. At least one conductive material portion can be formed in the remaining volume of the contact trench to form a contact via structure. Alternatively or additionally, a contact via structure can include a tensile stress-generating portion and a conductive material portion. In case the contact via structure is formed through an alternating stack of insulating layers and electrically conductive layers that include a compressive stress-generating material, the tensile stress-generating portion can at least partially cancel the compressive stress generated by the electrically conductive layers. The conductive material portion of the contact via structure can include a metallic material or a doped semiconductor material.
    Type: Grant
    Filed: October 29, 2015
    Date of Patent: July 4, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Somesh Peri, Sateesh Koka, Raghuveer S. Makala, Rahul Sharangpani, Matthias Baenninger, Jayavel Pachamuthu, Johann Alsmeier
  • Patent number: 9691884
    Abstract: Methods of making a monolithic three dimensional NAND string that include forming a stack of alternating first material layers and second material layers over a substrate, where each of the second material layers includes a layer of a first silicon oxide material between two layers of a second silicon oxide material different from the first silicon oxide material, etching the stack to form a front side opening in the stack, forming a memory film over a sidewall of the front side opening, and forming a semiconductor channel in the front side opening such that at least a portion of the memory film is located between the semiconductor channel and the sidewall of the front side opening, where at least one of an air gap or a material which has a dielectric constant below 3.9 is formed between the respective two layers of second silicon oxide material.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: June 27, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Raghuveer S. Makala, Yanli Zhang, Rahul Sharangpani, Yao-Sheng Lee, Senaka Krishna Kanakamedala, George Matamis, Johann Alsmeier
  • Publication number: 20170179026
    Abstract: A three dimensional NAND memory device includes word line driver devices located on or over a substrate, an alternating stack of word lines and insulating layers located over the word line driver devices, a plurality of memory stack structures extending through the alternating stack, each memory stack structure including a memory film and a vertical semiconductor channel, and through-memory-level via structures which electrically couple the word lines in a first memory block to the word line driver devices. The through-memory-level via structures extend through a through-memory-level via region located between a staircase region of the first memory block and a staircase region of another memory block.
    Type: Application
    Filed: September 19, 2016
    Publication date: June 22, 2017
    Inventors: Fumiaki Toyama, Hiroyuki Ogawa, Yoko Furihata, James Kai, Yuki Mizutani, Jixin Yu, Jin Liu, Johann Alsmeier
  • Publication number: 20170179151
    Abstract: A three dimensional NAND memory device includes word line driver devices located on or over a substrate, an alternating stack of word lines and insulating layers located over the word line driver devices, a plurality of memory stack structures extending through the alternating stack, each memory stack structure including a memory film and a vertical semiconductor channel, and through-memory-level via structures which electrically couple the word lines in a first memory block to the word line driver devices. The through-memory-level via structures extend through a through-memory-level via region located between a staircase region of the first memory block and a staircase region of another memory block.
    Type: Application
    Filed: September 19, 2016
    Publication date: June 22, 2017
    Inventors: James Kai, Jin Liu, Johann Alsmeier, Jixin Yu, Yoko Furihata, Hiroyuki Ogawa
  • Publication number: 20170179154
    Abstract: A three dimensional NAND memory device includes word line driver devices located on or over a substrate, an alternating stack of word lines and insulating layers located over the word line driver devices, a plurality of memory stack structures extending through the alternating stack, each memory stack structure including a memory film and a vertical semiconductor channel, and through-memory-level via structures which electrically couple the word lines in a first memory block to the word line driver devices. The through-memory-level via structures extend through a through-memory-level via region located between a staircase region of the first memory block and a staircase region of another memory block.
    Type: Application
    Filed: September 19, 2016
    Publication date: June 22, 2017
    Inventors: Yoko FURIHATA, Jixin YU, Hiroyuki OGAWA, James KAI, Jin LIU, Johann ALSMEIER