Patents by Inventor En-Hsing Chen

En-Hsing Chen 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: 20120049186
    Abstract: Test structures are formed during semiconductor processing with a single mask that is used in a manner that also allows alignment marks to be formed which do not interfere with one another as subsequent layers are patterned. The test structures can provide insight into performance characteristics of different types of devices as the semiconductor process proceeds.
    Type: Application
    Filed: August 31, 2010
    Publication date: March 1, 2012
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Patent number: 7998640
    Abstract: A mask is reused to form the same pattern in multiple layers in semiconductor processing. Reference marks that allow alignment accuracy to be checked are also formed with the mask. The manner of using the mask advantageously mitigates interference between reference marks in different layers.
    Type: Grant
    Filed: June 30, 2007
    Date of Patent: August 16, 2011
    Assignee: SanDisk Corporation
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Patent number: 7932157
    Abstract: Test structures are formed during semiconductor processing. The test structures allow performance characteristics to be monitored as the process proceeds. The test structures are formed with a single mask that is used in a manner that also allows alignment marks to be formed which do not interfere with one another as subsequent levels are patterned. The manner of using the mask also allows different types of test structures having different features to be formed. The different types of test structures can provide insight into performance characteristics of different types of devices.
    Type: Grant
    Filed: June 30, 2007
    Date of Patent: April 26, 2011
    Assignee: SanDisk Corporation
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Patent number: 7830028
    Abstract: Different types of test structures are formed during semiconductor processing. One type of test structure comprises features that are aligned with one another and that are formed from different layers. Other types of test structures comprise features formed from respective layers that are not aligned with other test structure features. The different types of test structures are formed with a single mask that is used in a manner that also allows alignment marks to be formed which do not interfere with one another as subsequent layers are patterned. The different types of test structures can provide insight into performance characteristics of different types of devices as the semiconductor process proceeds.
    Type: Grant
    Filed: June 30, 2007
    Date of Patent: November 9, 2010
    Assignee: SanDisk Corporation
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Patent number: 7508714
    Abstract: An exemplary NAND string memory array includes at least one plane of memory cells, said memory cells comprising thin film modifiable conductance switch devices and which cells are arranged in a plurality of series-connected NAND strings, said NAND strings including a series select device at each end thereof. Another exemplary NAND string memory array includes a group of more than four adjacent NAND strings within the same memory block each associated with a respective global bit line not shared by the other NAND string of the group. Another exemplary NAND string memory array includes NAND strings on identical pitch as their respective global bit lines.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: March 24, 2009
    Assignee: SanDisk 3D LLC
    Inventors: Luca G. Fasoli, Roy E. Scheuerlein, En-Hsing Chen, Sucheta Nallamothu, Maitreyee Mahajani, Andrew J. Walker
  • Patent number: 7505321
    Abstract: A three-dimensional flash memory array incorporates thin film transistors having a charge storage dielectric arranged in series-connected NAND strings to achieve a 4F2 memory cell layout. The memory array may be programmed and erased using only tunneling currents, and no leakage paths are formed through non-selected memory cells. Each NAND string includes two block select devices for respectively coupling one end of the NAND string to a global bit line, and the other end to a shared bias node. Pairs of NAND strings within a block share the same global bit line. The memory cells are preferably depletion mode SONOS devices, as are the block select devices. The memory cells may be programmed to a near depletion threshold voltage, and the block select devices are maintained in a programmed state having a near depletion mode threshold voltage. NAND strings on more than one layer may be connected to global bit lines on a single layer.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: March 17, 2009
    Assignee: SanDisk 3D LLC
    Inventors: Roy E. Scheuerlein, Christopher Petti, Andrew J. Walker, En-Hsing Chen, Sucheta Nallamothu, Alper Ilkbahar, Luca Fasoli, Igor Koutnetsov
  • Publication number: 20090004880
    Abstract: A mask is reused to form the same pattern in multiple layers in semiconductor processing. Reference marks that allow alignment accuracy to be checked are also formed with the mask. The manner of using the mask advantageously mitigates interference between reference marks in different layers.
    Type: Application
    Filed: June 30, 2007
    Publication date: January 1, 2009
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Publication number: 20090004879
    Abstract: Test structures are formed during semiconductor processing. The test structures allow performance characteristics to be monitored as the process proceeds. The test structures are formed with a single mask that is used in a manner that also allows alignment marks to be formed which do not interfere with one another as subsequent levels are patterned. The manner of using the mask also allows different types of test structures having different features to be formed. The different types of test structures can provide insight into performance characteristics of different types of devices.
    Type: Application
    Filed: June 30, 2007
    Publication date: January 1, 2009
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Publication number: 20090001615
    Abstract: Different types of test structures are formed during semiconductor processing. One type of test structure comprises features that are aligned with one another and that are formed from different layers. Other types of test structures comprise features formed from respective layers that are not aligned with other test structure features. The different types of test structures are formed with a single mask that is used in a manner that also allows alignment marks to be formed which do not interfere with one another as subsequent layers are patterned. The different types of test structures can provide insight into performance characteristics of different types of devices as the semiconductor process proceeds.
    Type: Application
    Filed: June 30, 2007
    Publication date: January 1, 2009
    Inventors: Calvin K. Li, Yung-Tin Chen, En-Hsing Chen, Paul Wai Kie Poon
  • Patent number: 7433233
    Abstract: An exemplary NAND string memory array provides for capacitive boosting of a half-selected memory cell channel to reduce program disturb effects of the half selected cell. To reduce the effect of leakage current degradation of the boosted level, multiple programming pulses of a shorter duration are employed to limit the time period during which such leakage currents may degrade the voltage within the unselected NAND strings. In addition, multiple series select devices at one or both ends of each NAND string further ensure reduced leakage through such select devices, for both unselected and selected NAND strings. In certain exemplary embodiments, a memory array includes series-connected NAND strings of memory cell transistors having a charge storage dielectric, and includes more than one plane of memory cells formed above a substrate.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: October 7, 2008
    Assignee: SanDisk 3D LLC
    Inventors: En-Hsing Chen, Andrew J. Walker, Roy E. Scheuerlein, Sucheta Nallamothu, Alper Ilkbahar, Luca G. Fasoli
  • Publication number: 20070242511
    Abstract: An exemplary NAND string memory array provides for capacitive boosting of a half-selected memory cell channel to reduce program disturb effects of the half selected cell. To reduce the effect of leakage current degradation of the boosted level, multiple programming pulses of a shorter duration are employed to limit the time period during which such leakage currents may degrade the voltage within the unselected NAND strings. In addition, multiple series select devices at one or both ends of each NAND string further ensure reduced leakage through such select devices, for both unselected and selected NAND strings. In certain exemplary embodiments, a memory array includes series-connected NAND strings of memory cell transistors having a charge storage dielectric, and includes more than one plane of memory cells formed above a substrate.
    Type: Application
    Filed: June 18, 2007
    Publication date: October 18, 2007
    Inventors: En-Hsing Chen, Andrew Walker, Roy Scheuerlein, Sucheta Nallamothu, Alper Ilkbahar, Luca Fasoli
  • Publication number: 20070217263
    Abstract: An exemplary NAND string memory array includes at least one plane of memory cells, said memory cells comprising thin film modifiable conductance switch devices and which cells are arranged in a plurality of series-connected NAND strings, said NAND strings including a series select device at each end thereof. Another exemplary NAND string memory array includes a group of more than four adjacent NAND strings within the same memory block each associated with a respective global bit line not shared by the other NAND string of the group. Another exemplary NAND string memory array includes NAND strings on identical pitch as their respective global bit lines.
    Type: Application
    Filed: May 21, 2007
    Publication date: September 20, 2007
    Inventors: Luca Fasoli, Roy Scheuerlein, En-Hsing Chen, Sucheta Nallamothu, Maitreyee Mahajani, Andrew Walker
  • Patent number: 7233522
    Abstract: An exemplary NAND string memory array provides for capacitive boosting of a half-selected memory cell channel to reduce program disturb effects of the half selected cell. To reduce the effect of leakage current degradation of the boosted level, multiple programming pulses of a shorter duration are employed to limit the time period during which such leakage currents may degrade the voltage within the unselected NAND strings. In addition, multiple series select devices at one or both ends of each NAND string further ensure reduced leakage through such select devices, for both unselected and selected NAND strings. In certain exemplary embodiments, a memory array includes series-connected NAND strings of memory cell transistors having a charge storage dielectric, and includes more than one plane of memory cells formed above a substrate.
    Type: Grant
    Filed: December 5, 2003
    Date of Patent: June 19, 2007
    Assignee: SanDisk 3D LLC
    Inventors: En-Hsing Chen, Andrew J. Walker, Roy E. Scheuerlein, Sucheta Nallamothu, Alper Ilkbahar, Luca G. Fasoli
  • Patent number: 7221588
    Abstract: An exemplary NAND string memory array includes at least one plane of memory cells, said memory cells comprising thin film modifiable conductance switch devices and which cells are arranged in a plurality of series-connected NAND strings, and NAND strings including a series select device at each end thereof. Another exemplary NAND string memory array includes a group of more than four adjacent NAND strings within the same memory block each associated with a respective global bit line not shared by the other NAND string of the group. Another exemplary NAND string memory array includes NAND strings on identical pitch as their respective global bit lines.
    Type: Grant
    Filed: December 5, 2003
    Date of Patent: May 22, 2007
    Assignee: Sandisk 3D LLC
    Inventors: Luca G. Fasoli, Roy E. Scheuerlein, En-Hsing Chen, Sucheta Nallamothu, Maitreyee Mahajani, Andrew J. Walker
  • Patent number: 7023739
    Abstract: An exemplary NAND string memory array provides for capacitive boosting of a half-selected memory cell channel to reduce program disturb effects of the half selected cell. To reduce the effect of leakage current degradation of the boosted level, multiple programming pulses of a shorter duration are employed to limit the time period during which such leakage currents may degrade the voltage within the unselected NAND strings. In addition, multiple series select devices at one or both ends of each NAND string further ensure reduced leakage through such select devices, for both unselected and selected NAND strings. In certain exemplary embodiments, a memory array includes series-connected NAND strings of memory cell transistors having a charge storage dielectric, and includes more than one plane of memory cells formed above a substrate.
    Type: Grant
    Filed: December 5, 2003
    Date of Patent: April 4, 2006
    Assignee: Matrix Semiconductor, Inc.
    Inventors: En-Hsing Chen, Andrew J. Walker, Roy E. Scheuerlein, Sucheta Nallamothu, Alper Ilkbahar, Luca G. Fasoli
  • Publication number: 20060067127
    Abstract: A method of programming a monolithic three-dimensional (3-D) memory having a plurality of levels of memory cells above a silicon substrate is disclosed. The method includes initializing a program voltage and program time interval; selecting a memory cell to be programmed within the three-dimensional memory having the plurality of levels of memory cells; applying a pulse having the program voltage and the program time interval to the selected memory cell; performing a read after write operation with respect to the selected memory cell to determine a measured threshold voltage value; and comparing the measured threshold voltage value to a minimum program voltage. In response to the comparison between the measured threshold voltage value and the minimum program voltage, the method further includes selectively applying at least one subsequent program pulse to the selected memory cell.
    Type: Application
    Filed: September 30, 2004
    Publication date: March 30, 2006
    Inventors: Luca Fasoli, Roy Scheuerlein, Alper Ilkbahar, En-Hsing Chen, Tanmay Kumar
  • Patent number: 7012299
    Abstract: The traditional nitride-only charge storage layer of a SONOS device is replaced by a multifilm charge storage layer comprising more than one dielectric material. Examples of such a multifilm charge storage layer are alternating layers of silicon nitride and silicon dioxide, or alternating layers of silicon nitride and aluminum oxide. The use of more than one material introduces additional barriers to migration of charge carriers within the charge storage layer, and improves both endurance and retention of a SONOS-type memory cell comprising such a charge storage layer.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: March 14, 2006
    Assignee: Matrix Semiconductors, Inc.
    Inventors: Maitreyee Mahajani, Andrew J. Walker, En-Hsing Chen
  • Patent number: 7005350
    Abstract: A three-dimensional flash memory array incorporates thin film transistors having a charge storage dielectric arranged in series-connected NAND strings to achieve a 4F2 memory cell layout. The memory array may be programmed and erased using only tunneling currents, and no leakage paths are formed through non-selected memory cells. Each NAND string includes two block select devices for respectively coupling one end of the NAND string to a global bit line, and the other end to a shared bias node. Pairs of NAND strings within a block share the same global bit line. The memory cells are preferably depletion mode SONOS devices, as are the block select devices. The memory cells may be programmed to a near depletion threshold voltage, and the block select devices are maintained in a programmed state having a near depletion mode threshold voltage. NAND strings on more than one layer may be connected to global bit lines on a single layer.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: February 28, 2006
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Andrew J. Walker, En-Hsing Chen, Sucheta Nallamothu, Roy E. Scheuerlein, Alper Ilkbahar, Luca Fasoli, Igor Koutnetsov, Christopher Petti
  • Patent number: 6960794
    Abstract: A thin film transistor with a channel less than 100 angstroms thick, preferably less than 80 angstroms thick, preferably less than 60 angstroms thick. The very thin channel reduces variability of threshold voltage from one TFT to the next. This is particularly advantageous for TFT memory arrays. It is possible that an extremely thin channel restricts the size of grains, forcing many small grains to be formed.
    Type: Grant
    Filed: December 31, 2002
    Date of Patent: November 1, 2005
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Andrew J. Walker, S. Brad Herner, Maitreyee Mahajani, En-Hsing Chen, Roy E. Scheuerlein, Sucheta Nallamothu, Mark Clark
  • Publication number: 20050128807
    Abstract: An exemplary NAND string memory array provides for capacitive boosting of a half-selected memory cell channel to reduce program disturb effects of the half selected cell. To reduce the effect of leakage current degradation of the boosted level, multiple programming pulses of a shorter duration are employed to limit the time period during which such leakage currents may degrade the voltage within the unselected NAND strings. In addition, multiple series select devices at one or both ends of each NAND string further ensure reduced leakage through such select devices, for both unselected and selected NAND strings. In certain exemplary embodiments, a memory array includes series-connected NAND strings of memory cell transistors having a charge storage dielectric, and includes more than one plane of memory cells formed above a substrate.
    Type: Application
    Filed: December 5, 2003
    Publication date: June 16, 2005
    Inventors: En-Hsing Chen, Andrew Walker, Roy Scheuerlein, Sucheta Nallamothu, Alper Ilkbahar, Luca Fasoli, James Cleeves