Patents by Inventor Chao-I Wu

Chao-I Wu 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: 20070297227
    Abstract: Multi-level cell memory devices comprise a charge trapping structure with an enlarged second bit operation window formed by hole injection through a gate electrode or substrate for producing multiple logic levels on each storage side of the charge trapping structure. A hole injection process is conducted through either a gate electrode or substrate to cause fringe-induced effect. Hole charges are stored in a charge trapping layer that intersects with a word line and the hole charges are stored along fringes of the word line. Each memory cell in the MLC memory device includes a total of 2 m bits with m bits for each side of the memory cell, a total of 2*2m multiple voltage threshold Vt distributions with 2m multiple voltage threshold Vt distributions for each side of the memory cell, and a total of 2*2m logic states with 2m logic states for each side of the memory cell.
    Type: Application
    Filed: December 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070296023
    Abstract: A charge monitoring device is described for monitoring charging effect during semiconductor manufacturing. In a first aspect of the invention, a charge storage MOS memory structure comprises a substrate body, an oxide-nitride-oxide structure that overlays a top surface of the substrate and extends above the edges between a source region and a drain region, and a polygate formed over the oxide-nitride-oxide structure. When a charging source, such as UV light or plasma, is projected onto the charge storage device, the polygate of the charge storage device protects the nitride layer from charging effect The light source charges side walls of the oxide-nitride-oxide structure.
    Type: Application
    Filed: June 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventors: Chao-I Wu, Ming Hsiu Lee
  • Publication number: 20070297240
    Abstract: Methods and structures are described for increasing a memory operation window in a charge trapping memory having a plurality of memory cells in which each memory cell is capable of storing multiple bits per memory cell. In a first aspect of the invention, a first method to increase a memory operation window in a two-bit-per-cell memory is described by applying a positive gate voltage, +Vg, to erase a memory cell to a negative voltage level. Alternatively, a negative gate voltage, ?Vg, is applied to the two-bit-per-cell memory for erasing the memory cell to a negative voltage level. A second method to increase a memory operation window is to erase a memory cell to a voltage level that is lower than an initial voltage threshold level. These two erasing methods can be implemented either before a programming step (i.e., a pre-program erase operation) or after a programming step (i.e., a post-program erase operation).
    Type: Application
    Filed: June 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070297244
    Abstract: Methods and structures are described for increasing a memory operation window in a charge trapping memory having a plurality of memory cells in which each memory cell is capable of storing multiple bits per memory cell. In a first aspect of the invention, a first method to increase a memory operation window in a two-bit-per-cell memory is described by applying a positive gate voltage, +Vg, to erase a memory cell to a negative voltage level. Alternatively, a negative gate voltage, ?Vg, is applied to the two-bit-per-cell memory for erasing the memory cell to a negative voltage level. A second method to increase a memory operation window is to erase a memory cell to a voltage level that is lower than an initial voltage threshold level. These two erasing methods can be implemented either before a programming step (i.e., a pre-program erase operation) or after a programming step (i.e., a post-program erase operation).
    Type: Application
    Filed: June 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070297243
    Abstract: Methods and structures are described for increasing a memory operation window in a charge trapping memory having a plurality of memory cells in which each memory cell is capable of storing multiple bits per memory cell. In a first aspect of the invention, a first method to increase a memory operation window in a two-bit-per-cell memory is described by applying a positive gate voltage, +Vg, to erase a memory cell to a negative voltage level. Alternatively, a negative gate voltage, ?Vg, is applied to the two-bit-per-cell memory for erasing the memory cell to a negative voltage level. A second method to increase a memory operation window is to erase a memory cell to a voltage level that is lower than an initial voltage threshold level. These two erasing methods can be implemented either before a programming step (i.e., a pre-program erase operation) or after a programming step (i.e., a post-program erase operation).
    Type: Application
    Filed: June 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070297241
    Abstract: Charge trapping memory devices and methods are described for increasing a second bit operation window by a fringe-induced effect. The fringe-induced effect occurs in areas underneath a word line so that when a hole injection method is applied to a memory device, hole charges are stored in a charge trapping layer that intersects with a word line and the hole charges are stored along fringes of the word line. In one embodiment, a virtual ground array comprises a charge trapping layer that is disposed between two dielectrics such that there is not a charge trapping layer over source and drain regions. After a hole injection is applied to the virtual ground array, hole charges are stored along fringes of each word line given the fringes of the word line has a larger electrical field relative to non-fringe areas of the word line.
    Type: Application
    Filed: December 21, 2006
    Publication date: December 27, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070290251
    Abstract: A NAND based memory device uses inversion bit lines in order to eliminate the need for implanted bit lines. As a result, the cell size can be reduced, which can provide greater densities in smaller packaging. In another aspect, a method for fabricating a NAND based memory device that uses inversion bit lines is disclosed.
    Type: Application
    Filed: June 16, 2006
    Publication date: December 20, 2007
    Applicant: Macronix International Co., Ltd.
    Inventor: Chao-I Wu
  • Publication number: 20070291541
    Abstract: A virtual ground array structure uses inversion bit lines in order to eliminate the need for implanted bit lines. As a result, the cell size can be reduced, which can provide greater densities and smaller packaging.
    Type: Application
    Filed: June 16, 2006
    Publication date: December 20, 2007
    Applicant: MACRONIX INTERNATIONAL CO., LTD.
    Inventor: Chao-I Wu
  • Publication number: 20070267677
    Abstract: A non-volatile memory device comprises a substrate with the dielectric layer formed thereon. A control gate and a floating gate are then formed on top of the dielectric layer. Accordingly, a non-volatile memory device can be constructed using a single poly process that is compatible with conventional CMOS processes. In addition, an assist gate, or assist gates are formed on the dielectric layer next to and between the control gate and floating gate respectively. The assist gates are used to form inversion diffusion regions in the substrate. By using the assist gates to form inversion diffusion regions, the overall size of the device can be reduced, which can improve device density.
    Type: Application
    Filed: May 17, 2006
    Publication date: November 22, 2007
    Applicant: MACRONIX INTERNATIONAL CO., LTD.
    Inventors: Ming-Chang Kuo, Chao-I Wu
  • Patent number: 7292478
    Abstract: A non-volatile memory cell is described, including a semiconductor substrate with a trench therein, a charge-trapping layer in the trench, a gate disposed in the trench and separated from the substrate by at least the charge-trapping layer, and S/D regions in the substrate beside the trench. The gate includes a p-doped semiconductor material, so that the memory cell is particularly suitable to erase through hole injection from the gate.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: November 6, 2007
    Assignee: Macronix International Co., Ltd.
    Inventors: Chao-Lun Yu, Chao-I Wu
  • Publication number: 20070247925
    Abstract: A method of programming data regions in a nitride read-only memory cell that, in an erased state, exhibits a low Vt value by first programming a data region that is to be programmed to a highest Vt value. Remaining data regions in the nitride read-only memory cell are programmed in a time order according to their descending Vt values. For a nitride read-only memory cell that, in an erased state, exhibits a high Vt value, a data region that is to be programmed to a lowest Vt value is programmed first with remaining data regions programmed in a time order according to their ascending Vt values.
    Type: Application
    Filed: June 22, 2007
    Publication date: October 25, 2007
    Inventors: Hsiang-Lan Lung, Chao-I Wu
  • Publication number: 20070236994
    Abstract: The present invention describes a uniform program method and a uniform erase method of a charge trapping memory by employing a substrate transient hot electron technique for programming, and a substrate transient hot hole technique for erasing, which emulate an FN tunneling method for NAND memory operation. The methods of the present invention are applicable to a wide variety of charge trapping memories including n-channel or p-channel SONOS types of memories and floating gate (FG) type memories. the programming of the charge trapping memory is conducted using a substrate transient hot electron injection in which a body bias voltage Vb has a short pulse width and a gate bias voltage Vg has a pulse width that is sufficient to move electrons from a channel region to a charge trapping structure.
    Type: Application
    Filed: January 19, 2007
    Publication date: October 11, 2007
    Applicant: Macronix International Co., Ltd.
    Inventors: Tzu Hsuan Hsu, Chao-I Wu, Kuang Yeu Hsieh, Ya-Chin King
  • Publication number: 20070232000
    Abstract: A method of fabricating a non-volatile memory is provided. A stacked structure is formed over a substrate, and the stacked structure has a gate dielectric layer and a floating gate thereon. A first dielectric layer, a second dielectric layer and a third dielectric layer are respectively formed over the top and the sidewalls of the stacked structure and the exposed substrate. A charge storage layer covers over the top and sidewalls of the stacked structure. Also, a pair of auxiliary gates is formed over the substrate beside the charge storage layer, and a gap is between the auxiliary gates and the charge storage layer.
    Type: Application
    Filed: June 8, 2007
    Publication date: October 4, 2007
    Applicant: MACRONIX INTERNATIONAL CO., LTD.
    Inventors: Ming-Chang Kuo, Chao-I Wu
  • Publication number: 20070212800
    Abstract: A semiconductor process test structure comprises a gate electrode, a charge-trapping layer, and a diffusion region. The test structure is a capacitor-like structure in which the charge-trapping layer will trap charges during various processing steps. A charge pump current can be used to detect the charging effect during various processing steps.
    Type: Application
    Filed: March 8, 2006
    Publication date: September 13, 2007
    Inventors: Chao-I Wu, Ming Lee, Ming-Chang Kuo
  • Patent number: 7266014
    Abstract: A method of operating a non-volatile memory is provided, wherein the non-volatile memory at least includes: a gate structure formed by stacking a tunneling dielectric layer, charge trapping layer, a dielectric layer and a gate conducting layer sequentially, and a source region and a drain region. When the operating method is carried out, a ultraviolet is irradiated to the non-volatile memory to inject electrons into the charge trapping layer to erase the non-volatile memory, and a negative voltage is applied to the gate conductive layer and a positive voltage is applied to the drain region to program the non-volatile memory by band-to-band induced hot hole injection.
    Type: Grant
    Filed: August 1, 2005
    Date of Patent: September 4, 2007
    Assignee: MACRONIX International Co., Ltd
    Inventors: Chao-I Wu, Ming-Hsiu Lee
  • Publication number: 20070200164
    Abstract: A single poly embedded memory structure comprises an access transistor and a storage device formed on a silicon substrate. The access transistor comprises source and drain diffusion regions implanted in the silicon substrate and a polysilicon control gate formed over the silicon substrate between the source and drain diffusion regions. The storage structure comprises a source and drain diffusion regions implanted in the silicon substrate and a polysilicon floating gate formed over the silicon substrate between the source and drain diffusion region; however, the source diffusion region comprises a double diffusion structure.
    Type: Application
    Filed: February 27, 2006
    Publication date: August 30, 2007
    Inventor: Chao-I Wu
  • Patent number: 7251167
    Abstract: A method of programming data regions in a nitride read-only memory cell is described. In an erased state, the nitride read-only memory cell exhibits a low Vt value. A data region that is to be programmed to a highest Vt value is programmed first. Remaining data regions in the nitride read-only memory cell are programmed in a time order according to their descending Vt values. For a nitride read-only memory cell that, in an erased state, exhibits a high Vt value, a data region that is to be programmed to a lowest Vt value is programmed first with remaining data regions programmed in a time order according to their ascending Vt values.
    Type: Grant
    Filed: December 29, 2004
    Date of Patent: July 31, 2007
    Assignee: Macronix International Co., Ltd.
    Inventors: Hsiang-Lan Lung, Chao-I Wu
  • Publication number: 20070161193
    Abstract: A memory array comprising vertical memory cells does not require any isolation layers between cells. Thus, a very compact, high density memory array can be achieved. Each memory cell in the memory array is configured to store 4 bits of data per cell. Multi-level charge techniques can be used to increase the number of bit per cell and achieve further increased density for the memory array.
    Type: Application
    Filed: January 6, 2006
    Publication date: July 12, 2007
    Inventors: Tzu-Hsuan Hsu, Ming-Hsiu Lee, Chao-I Wu, Ming-Chang Kuo
  • Patent number: 7242052
    Abstract: A stacked structure is formed over a substrate, and the stacked structure has a gate dielectric layer and a floating gate thereon. A first dielectric layer, a second dielectric layer and a third dielectric layer are respectively formed over the top and the sidewalls of the stacked structure and the exposed substrate. A charge storage layer covers over the top and sidewalls of the stacked structure. Also, a pair of auxiliary gates is formed over the substrate beside the charge storage layer, and a gap is between the auxiliary gates and the charge storage layer.
    Type: Grant
    Filed: July 11, 2005
    Date of Patent: July 10, 2007
    Assignee: Macronix International Co., Ltd.
    Inventors: Ming-Chang Kuo, Chao-I Wu
  • Publication number: 20070138539
    Abstract: A non-volatile memory cell may include a semiconductor substrate; a source region in a portion of the substrate; a drain region within a portion of the substrate; a well region within a portion of the substrate. The memory cell may further include a first carrier tunneling layer over the substrate; a charge storage layer over the first carrier tunneling layer; a second carrier tunneling layer over the charge storage layer; and a conductive control gate over the second carrier tunneling layer. Specifically, the drain region is spaced apart from the source region, and the well region may surround at least a portion of the source and drain regions. In one example, the second carrier tunneling layer provides hole tunneling during an erasing operation and may include at least one dielectric layer.
    Type: Application
    Filed: December 15, 2005
    Publication date: June 21, 2007
    Inventors: Chao-I Wu, Tzu-Hsuan Hsu, Hang-Ting Lue