Patents Assigned to TC Lab, Inc.
  • Patent number: 11763872
    Abstract: A memory architecture for 3-dimensional thyristor cell arrays is disclosed. Thyristor memory cells are connected in a 3-dimensional cross-point array to form a bit line cluster. The bit line clusters are connected in parallel to sense amplifier and write circuits through multiplexer/demultiplexer circuits. Control circuits select one of the bit line clusters during a read or write operation while the non-selected bit line clusters are not activated to avoid disturbs and power consumption in the non-selected bit line clusters. The bit line clusters, multiplexer/demultiplexer circuits, and sense amplifier and write circuits from a memory array tile (MAT).
    Type: Grant
    Filed: September 28, 2021
    Date of Patent: September 19, 2023
    Assignee: TC Lab, Inc.
    Inventor: Bruce L. Bateman
  • Patent number: 11605636
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of memory cells. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. The memory cells preferably are thyristors. Methods of fabricating the array are described.
    Type: Grant
    Filed: August 18, 2020
    Date of Patent: March 14, 2023
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 11444085
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of thyristor memory cells with silicon-germanium base regions. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. Methods of fabricating the array are described.
    Type: Grant
    Filed: April 13, 2021
    Date of Patent: September 13, 2022
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 11444084
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of thyristor memory cells and associated peripheral circuitry. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Methods of fabricating the array are described.
    Type: Grant
    Filed: March 30, 2021
    Date of Patent: September 13, 2022
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 11222681
    Abstract: Integrated circuit devices having multiple level arrays of thyristor memory cells are created using a stack of ONO layers through which NPNPNPN layered silicon pillars are epitaxially grown in-situ. Intermediate conducting lines formed in place of the removed nitride layer of the ONO stack contact the middle P-layer of silicon pillars. The silicon pillars form two arrays of thyristor memory cells, one stacked upon the other, having the intermediate conducting lines as common connections to both arrays. The stacked arrays can also be provided with assist-gates.
    Type: Grant
    Filed: April 28, 2020
    Date of Patent: January 11, 2022
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 11133049
    Abstract: A memory architecture for 3-dimensional thyristor cell arrays is disclosed. Thyristor memory cells are connected in a 3-dimensional cross-point array to form a bit line cluster. The bit line clusters are connected in parallel to sense amplifier and write circuits through multiplexer/demultiplexer circuits. Control circuits select one of the bit line clusters during a read or write operation while the non-selected bit line clusters are not activated to avoid disturbs and power consumption in the non-selected bit line clusters. The bit line clusters, multiplexer/demultiplexer circuits, and sense amplifier and write circuits from a memory array tile (MAT).
    Type: Grant
    Filed: December 19, 2018
    Date of Patent: September 28, 2021
    Assignee: TC Lab, Inc.
    Inventor: Bruce L. Bateman
  • Patent number: 11114438
    Abstract: A method of writing data into a volatile thyristor memory cell array and maintaining the data with refresh is disclosed.
    Type: Grant
    Filed: November 5, 2020
    Date of Patent: September 7, 2021
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Bruce L. Bateman, Valery Axelrad, Charlie Cheng
  • Patent number: 10978456
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of thyristor memory cells with silicon-germanium base regions. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. Methods of fabricating the array are described.
    Type: Grant
    Filed: June 26, 2020
    Date of Patent: April 13, 2021
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10978297
    Abstract: A method of making stacked lateral semiconductor devices is disclosed. The method includes depositing a stack of alternating layers of different materials. Slots or holes are cut through the layers for subsequent formation of single crystal semiconductor fences or pillars. When each of the alternating layers of one material are removed space is provided for formation of single crystal semiconductor devices between the remaining layers. The devices are doped as the single crystal silicon is formed.
    Type: Grant
    Filed: May 24, 2018
    Date of Patent: April 13, 2021
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10748903
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of memory cells. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. The memory cells preferably are thyristors. Methods of fabricating the array are described.
    Type: Grant
    Filed: April 19, 2018
    Date of Patent: August 18, 2020
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10700069
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of thyristor memory cells with silicon-germanium base regions. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Select transistors enable the use of folded bit lines. Methods of fabricating the array are described.
    Type: Grant
    Filed: June 13, 2018
    Date of Patent: June 30, 2020
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10636473
    Abstract: Integrated circuit devices having multiple level arrays of thyristor memory cells are created using a stack of ONO layers through which NPNPNPN layered silicon pillars are epitaxially grown in-situ. Intermediate conducting lines formed in place of the removed nitride layer of the ONO stack contact the middle P-layer of silicon pillars. The silicon pillars form two arrays of thyristor memory cells, one stacked upon the other, having the intermediate conducting lines as common connections to both arrays. The stacked arrays can also be provided with assist-gates.
    Type: Grant
    Filed: July 11, 2018
    Date of Patent: April 28, 2020
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10573650
    Abstract: A semiconductor structure for a DRAM is described having multiple layers of arrays of thyristor memory cells and associated peripheral circuitry. Memory cells in a vertical string extending through the layers have an electrical connection to one terminal of the memory cells in that string. Word lines couple the strings together. Each layer of the array also includes bit line connections to memory cells on that layer. Methods of fabricating the array are described.
    Type: Grant
    Filed: August 21, 2018
    Date of Patent: February 25, 2020
    Assignee: TC Lab, Inc.
    Inventor: Harry Luan
  • Patent number: 10553269
    Abstract: Aspects of DDR and thyristor memory cell RAMs are optimally combined for high-speed data transfer into and out of RAMs. After a Read operation in which data from a selected row of memory cells in an array are latched, a Burst operation selectively moves the latched data from the array or latches external data. At the same time as the Burst data transfer, all the memory cells of the selected row are turned off or on by a write operation. In the following Write-Back & Pre-charge operation, the latched data bits which are complementary to the memory cell state of the Burst write operation are written back into the corresponding memory cells in the selected row. As part of a DDR-like activation cycle, data can be transferred to and from the memory cell array RAM at high-speed.
    Type: Grant
    Filed: September 6, 2018
    Date of Patent: February 4, 2020
    Assignee: TC Lab, Inc.
    Inventor: Bruce L. Bateman
  • Patent number: 10553588
    Abstract: Memory cells are formed with vertical thyristors to create a volatile memory array. Power consumption in such arrays is reduced or controlled with various techniques including encoding the data stored in the arrays.
    Type: Grant
    Filed: June 21, 2018
    Date of Patent: February 4, 2020
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Bruce L. Bateman, Valery Axelrad, Charlie Cheng
  • Patent number: 10535657
    Abstract: Isolation between vertical thyristor memory cells in an array is improved with isolation regions between the vertical thyristor memory cells. The isolation regions are formed by electrically isolating cores surrounded by insulating material, such as silicon dioxide, in trenches between the memory cells. The electrically isolating cores may be tubes of air or conducting rods. Methods of constructing the isolation regions in a processes for manufacturing vertical thyristor memory cell arrays are also disclosed.
    Type: Grant
    Filed: August 22, 2017
    Date of Patent: January 14, 2020
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Valery Axelrad
  • Patent number: 10529718
    Abstract: Operations with reduced current overall are performed on single thyristor memory cells forming a volatile memory cell cross-point array. A first voltage is applied across a first group of memory cells for the operation and a lower second voltage is applied across other groups of memory cells. The first voltage is then applied across a second group of memory cells while the second voltage is applied across the other groups including the first group of memory cells and repeated until the operations covers all the groups.
    Type: Grant
    Filed: June 21, 2018
    Date of Patent: January 7, 2020
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Bruce L. Bateman, Valery Axelrad, Charlie Cheng
  • Patent number: 10460789
    Abstract: A volatile memory array using vertical thyristors is disclosed together with methods of operating the array to read data from and write data to the array.
    Type: Grant
    Filed: July 9, 2018
    Date of Patent: October 29, 2019
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Bruce L. Bateman, Valery Axelrad, Charlie Cheng
  • Patent number: 10453515
    Abstract: This invention relates to thyristor memory cells with MOS assist gates for enhanced operations. This invention solves various disturb problems in cross point memory array using the thyristor memory cells, including the techniques for protecting stored data inside unselected and half selected bit cells, for recovering weakened stored data in disturbed bit cells, and for effectively shutting off bit cells with minimum disturbance.
    Type: Grant
    Filed: May 10, 2018
    Date of Patent: October 22, 2019
    Assignee: TC Lab, Inc.
    Inventor: Frank Guo
  • Patent number: 10438952
    Abstract: A method of writing data into a volatile thyristor memory cell array and maintaining the data with refresh is disclosed.
    Type: Grant
    Filed: July 24, 2017
    Date of Patent: October 8, 2019
    Assignee: TC Lab, Inc.
    Inventors: Harry Luan, Bruce L. Bateman, Valery Axelrad, Charlie Cheng