Program Gate Patents (Class 365/185.14)
  • Patent number: 7149118
    Abstract: Methods and apparatuses for programming a single-poly pFET-based nonvolatile memory cell bias the cell so that band-to-band tunneling (BTBT) is induced and electrons generated by the BTBT are injected onto a floating gate of the cell. Following a predetermined event, the single-poly pFET is biased to induce impact-ionized hot-electron injection (IHEI). The predetermined event may be, for example, the expiration of a predetermined time period or a determination that a channel has been formed by the BTBT injection process that is sufficiently conducting to support IHEI. Employing BTBT permits a previously overerased or stuck bit to be “unstuck” or “removed” and thus be made usable (i.e., able to be programmed) again.
    Type: Grant
    Filed: September 7, 2004
    Date of Patent: December 12, 2006
    Assignee: Impinj, Inc.
    Inventors: Christopher J. Diorio, Todd E. Humes
  • Patent number: 7136308
    Abstract: A memory system includes an active storage circuit and at least one base storage circuit. The at least one base storage circuit is coupled to the active storage circuit though at least one pass gate, at least one driver and a bit line. The at least one pass gate and the at least one driver have a device size substantially similar to a device size of each one of the devices in the active storage circuit and the at least one base storage circuit. A method of swapping data between two storage circuits is also described.
    Type: Grant
    Filed: November 1, 2004
    Date of Patent: November 14, 2006
    Assignee: Sun Microsystems, Inc.
    Inventors: Shree Kant, Kenway Tam, Poonacha P. Kongetira, Yuan-Jung D Lin, Zhen W. Liu, Kathirgamar Aingaran
  • Patent number: 7130221
    Abstract: A method for altering and reading the contents of a memory cell includes the steps of: applying programming voltages to a first control gate and to a second control gate to cause carriers to be injected and trapped in either a first charge trapping region or in a second charge trapping region; applying erasing voltages to the first control gate and to the second control gate to cause the trapped carriers to be removed from the first charge trapping region and/or the second charge trapping region; and applying a sequence of reading voltages to the first control gate and to the second control gate for determining a state of each of the first and the second charge trapping regions.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: October 31, 2006
    Assignee: Macronix International Co., Ltd.
    Inventors: ChiaHua Ho, Hang-Ting Lue
  • Patent number: 7120055
    Abstract: A selected wordline that is coupled to a cell to be programmed is biased during a program operation. The unselected wordlines are biased with a negative potential to reduce the cell leakage at programming bitline potential. A programming pulse is applied to the bitline coupled to the cell to be programmed. During verification, the unselected wordlines are biased back to ground potential.
    Type: Grant
    Filed: March 3, 2006
    Date of Patent: October 10, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Jeffrey Alan Kessenich
  • Patent number: 7116579
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising memory elements, a write state machine for performing a sequence of a program or erase operation with respect to the memory array, a decoder for decoding a signal indicating a current state of the write state machine, which is output from the write state machine, and outputting a status signal indicating a status of the program or erase operation with respect to the memory array, a status register for storing the status signal, and an output circuit for outputting the status signal stored in the status register. Each memory element comprises a gate electrode, a channel region, diffusion regions, and memory function sections provided on opposite sides of the gate electrode and having a function of retaining charges.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: October 3, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Patent number: 7110297
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising memory elements. Each memory element comprises a gate electrode, a channel region, first and second diffusion regions, and first and second memory function sections provided an opposite aides of the gate electrode and having a function of retaining charges. The device further comprises a row decoder for selecting a word line in accordance with a row address, and a write control circuit for applying a write pulse to a bit line, which is connected to one of the first and second diffusion regions of the memory element connected to the selected word line, in accordance with a column address. The write control circuit controls the application of the write pulse so that a quantity of charges retained in one of the first and second memory function sections corresponds to a value of multibit data.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: September 19, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshinao Morikawa, Masaru Nawaki, Hiroshi Iwata, Akihide Shibata
  • Patent number: 7106630
    Abstract: A semiconductor storage device is provided, which comprises a memory array comprising a plurality of memory elements, a section for performing an erase or program operation with respect to the memory array, a section for receiving a suspend command, and in response to the suspend command, suspending the erase or program operation, and a section for receiving a resume command, and in response to the resume command, resuming the suspended erase or program operation. Each of the plurality of memory elements comprises a gate electrode provided via a gate insulating film on a semiconductor layer, a channel region provided under the gate electrode, diffusion regions provided on opposite sides of the channel region and having a conductivity type opposite to that of the channel region, and memory function sections provided on opposite sides of the gate electrode and having a function of retaining charges.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: September 12, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Koji Hamaguchi, Masaru Nawaki, Yoshinao Morikawa, Hiroshi Iwata, Akihide Shibata
  • Patent number: 7092293
    Abstract: A configuration circuit includes a latch and a dedicated non-volatile memory cell. The non-volatile memory cell is initially programmed or erased. The latch is then set to store a first logic value by coupling the latch to a first voltage supply terminal in response to an activated control signal. When the control signal is de-activated, the latch is de-coupled from the first voltage supply terminal and coupled to the non-volatile memory cell. If the non-volatile memory cell is programmed, the latch is coupled to a second voltage supply terminal, thereby storing a second logic value in the latch. If the non-volatile memory cell is erased, the latch is isolated from the second voltage supply terminal, and the first logic value remains stored in the latch. The latch can also be directly written through one or more access transistors, thereby facilitating testing.
    Type: Grant
    Filed: November 25, 2003
    Date of Patent: August 15, 2006
    Assignee: Xilinx, Inc.
    Inventors: Phillip A. Young, Sunhom Paak
  • Patent number: 7088618
    Abstract: A characteristic evaluating method of precisely obtaining a resistance value of an offset region in a semiconductor memory element constructed so that the resistance value of the offset region positioned below a memory function element formed on one side or both sides of a gate electrode changes according to an amount of charges or a polarization state of charges accumulated in said memory function element includes: a step of obtaining each of a resistance value between two diffusion regions inclusive formed on both sides of a channel region disposed just below the gate electrode of the semiconductor memory element via a gate insulating film, a resistance value of the channel region, and a resistance value of the diffusion regions; and a step of calculating the resistance value of the offset region which isolates the channel region and the diffusion region from each other on the basis of a result of subtracting the resistance value of the channel region and the resistance value of the diffusion regions from t
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: August 8, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kozo Hoshino, Hiroshi Iwata, Akihide Shibata
  • Patent number: 7072215
    Abstract: Variations in memory array and cell configuration are shown, which eliminate punch-through disturb, reverse-tunnel. Several configurations are shown which range from combined and separate source lines for each row of cells, a two transistor cell containing a read transistor and a program transistor connected by a merged floating gate, and a two transistor cell where the program transistor has an extra implant to raise the Vt of the transistor to protect against punch-through disturb. A method is also described to rewrite disturbed cells, which were not selected to be programmed.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: July 4, 2006
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventor: Yeu-Der Chih
  • Patent number: 7057931
    Abstract: A method for programming a storage element and a storage element programmed using gate induced junction leakage current are provided. The element may include at least a floating gate on a substrate, an active region in the substrate, and a second gate adjacent to the floating gate. The method may include the steps of: creating an inversion region in the substrate below the floating gate by biasing the first gate; and creating a critical electric field adjacent to the second gate. Creating a critical electric field may comprise applying a first positive bias to the active region; and applying a bias less than the first positive bias to the second gate. The element further includes a first bias greater than zero volts applied to the active region and a second bias greater than the first bias applied to the floating gate and a third bias less than or equal to zero applied to the second gate.
    Type: Grant
    Filed: November 7, 2003
    Date of Patent: June 6, 2006
    Assignee: Sandisk Corporation
    Inventors: Jeffrey W. Lutze, Chan-Sui Pang
  • Patent number: 7057934
    Abstract: A flash memory includes multi-level cells (MLC) that are programmed with a combination of coarse gate voltage steps and fine gate voltage steps. The multi-level cells include floating gate transistors that are programmed by modifying the threshold voltages of the floating gate transistors. Coarse gate voltage steps are used until the threshold voltage any of the transistors being programmed reaches a reference value, and fine steps are used thereafter.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: June 6, 2006
    Assignee: Intel Corporation
    Inventors: Sreeram Krishnamachari, Karthikeyan Ramamurthi
  • Patent number: 7042763
    Abstract: A method of selectively programming nonvolatile memory cells in which multiple programming voltages are used to obtain the desired voltage on the storage nodes of the cells selected for programming, while the storage nodes of unselected cells remain undisturbed.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: May 9, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Yuri Mirgorodski, Pavel Poplevine, Peter J. Hopper, Andrew J. Franklin
  • Patent number: 7038945
    Abstract: A selected wordline that is coupled to a cell to be programmed is biased during a program operation. The unselected wordlines are biased with a negative potential to reduce the cell leakage at programming bitline potential. A programming pulse is applied to the bitline coupled to the cell to be programmed. During verification, the unselected wordlines are biased back to ground potential.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: May 2, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Jeffrey Alan Kessenich
  • Patent number: 7038282
    Abstract: A semiconductor storage device includes a voltage supply circuit generating a voltage of 5V, a voltage polarity inversion circuit generating a voltage of ?5V, a select-and-connect circuit supplying the voltages of 5V and ?5V to a memory cell array, a 5 V voltage level detection circuit detecting the voltage derived from the voltage supply circuit, and a ?5 V voltage level detection circuit detecting the voltage derived from the voltage polarity inversion circuit. Absolute values of the voltages detected by the voltage level detection circuits are lower than ever before. This allows a gate insulation film to be thinner. A memory-function film is formed on both sides of a gate electrode in the semiconductor storage device. This also make the gate insulation film thinner. The thin gate insulation film suppresses the short-channel effect, so that each memory element of the memory cell array is miniaturized.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: May 2, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kei Tokui, Hiroshi Iwata, Yoshifumi Yaoi, Akihide Shibata, Masaru Nawaki
  • Patent number: 7035145
    Abstract: A method is provided for programming a memory cell of an electrically erasable programmable read only memory. The memory cell is fabricated on a substrate and comprises a source region, a drain region, a floating gate, and a control gate. The memory cell has a threshold voltage selectively configurable into one of at least three programming states. The method includes generating a drain current between the drain region and the source region by applying a drain-to-source bias voltage between the drain region and the source region. The method further includes injecting hot electrons from the drain current to the floating gate by applying a gate voltage to the control gate. A selected threshold voltage for the memory cell corresponding to a selected one of the programming states is generated by applying a selected constant drain-to-source bias voltage and a selected gate voltage.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: April 25, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Chun Chen, Kirk D. Prall
  • Patent number: 7035144
    Abstract: There is provided a flash memory device with multi-level cell and a reading and programming method thereof. The flash memory device with multi-level cell includes a memory cell array, a unit for precharging bit line, a bit line voltage supply circuit for supplying a voltage to the bit line, and first to third latch circuits each of which performs different function from each other. The reading and programming methods are performed by LSB and MSB reading and programming operations. A reading method in the memory device is achieved by reading an LSB two times and by reading an MSB one time. A programming method is achieved by programming an LSB one time and programming an MSB one time. Data having multi-levels can be programmed into memory cells by two times programming operations.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: April 25, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Dong-Hwan Kim, Yeong-Taek Lee
  • Patent number: 7027329
    Abstract: A semiconductor memory has a memory cell matrix including a plurality of first and second cell columns alternately arranged along a row-direction, each of cell columns is implemented by a plurality of memory cell transistors, and peripheral circuits configured to drive the memory cell matrix and to read information from the memory cell matrix. The peripheral circuit encompasses (a) a leading program circuit configured to write first data into memory cell transistors in the first cell columns, (b) a lagging program circuit configured to write second data into memory cell transistors in the second cell columns after the first data are written, and (c) a voltage controller configured to control variation of threshold voltages for the memory cell transistors of the first cell columns.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: April 11, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Makoto Sakuma, Fumitaka Arai, Riichiro Shirota, Yasuhiko Matsunaga
  • Patent number: 7023731
    Abstract: A semiconductor memory device including: a memory cell array in which memory cells are arranged; a plurality of terminals for accepting commands issued by an external user; a command interface circuit for interfacing between the external user and the memory cell array; a write state machine for controlling the programming and erasing operations; and an output circuit for outputting an internal signal to the plurality of terminals, wherein the memory cell includes a gate electrode formed over a semiconductor layer via a gate insulating film, a channel region disposed below the gate electrode, diffusion regions disposed on both sides of the channel region and having a conductive type opposite to that of the channel region, and memory functional elements formed on both sides of the gate electrode and having the function of retaining charges.
    Type: Grant
    Filed: May 18, 2004
    Date of Patent: April 4, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Koji Hamaguchi, Masaru Nawaki, Yoshinao Morikawa, Hiroshi Iwata, Akihide Shibata
  • Patent number: 7023732
    Abstract: The present invention is to propose an data erasing method, a memory apparatus, and a data erasing circuit which are able to reduce the time required to boost the potential of the semiconductor substrate thereby to reduce the time required to erase data. Namely, a memory apparatus having a data erasing circuit that erases stored data by applying an erasing voltage between a semiconductor substrate and a control gate so as to discharge electric charges accumulated in a floating gate is disclosed. In this case, the data erasing circuit boosts a potential of the semiconductor substrate side while placing the control gate into its floating state; and applies an erasing voltage between the semiconductor substrate and the control gate to make the potential of the control gate to a predetermined potential.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: April 4, 2006
    Assignee: Sony Corporation
    Inventors: Shunji Sekimoto, Tomohiro Namise
  • Patent number: 7020027
    Abstract: A method of programming a nonvolatile memory cell in which a ramped control voltage is used to obtain the desired voltage on the storage node.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: March 28, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Pavel Poplevine, Yuri Mirgorodski, Andrew J. Franklin, Peter J. Hopper
  • Patent number: 7009244
    Abstract: An memory device, and method of making same, that includes source and drain regions defining a channel region therebetween. A select gate is formed over and insulated from a first portion of the channel region. A conductive floating gate is disposed over and insulated from the source region and a second portion of the channel region. A notch is formed in the floating gate bottom surface having an edge that is either aligned with an edge of the source region or is disposed over the source region. A conductive control gate is disposed adjacent to the floating gate. By having the source region terminate under the thicker insulation region provided by the notch, the breakdown voltage of the source junction is increased. Alternately, the lower portion of the floating gate is formed entirely over the source region, for producing fringing fields to control the adjacent portion of the channel region.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: March 7, 2006
    Assignee: Integrated Memory Technologies, Inc.
    Inventors: Ching-Shi Jenq, Ting P. Yen
  • Patent number: 7003619
    Abstract: The preferred embodiments described herein provide a memory device and method for storing and reading a file system structure in a write-once memory array. In one preferred embodiment, a plurality of bits representing a file system structure is inverted and stored in a write-once memory array. When the inverted plurality of bits is read from the memory array, the bits are inverted to provide the file system structure bits in their original, non-inverted configuration. With this preferred embodiment, a file system structure can be updated to reflect data stored in the memory array after the file system structure was written. Other preferred embodiments are provided, and each of the preferred embodiments described herein can be used alone or in combination with one another.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: February 21, 2006
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Christopher S. Moore, James E. Schneider, J. James Tringali, Roger W. March
  • Patent number: 6996660
    Abstract: The preferred embodiments described herein provide a memory device and method for storing and reading data in a write-once memory array. In one preferred embodiment, a plurality of bits representing data is inverted and stored in a write-once memory array. When the inverted plurality of bits is read from the memory array, the bits are inverted to provide the data in its original, non-inverted configuration. By storing data bits in an inverted form, the initial, un-programmed digital state of the memory array is redefined as the alternative, programmed digital state. Other preferred embodiments are provided, and each of the preferred embodiments described herein can be used alone or in combination with one another. For example, the embodiments in which data bits are inverted can be used alone or in combination with the embodiments in which data is redirected.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: February 7, 2006
    Assignee: Matrix Semiconductor, Inc.
    Inventors: Christopher S. Moore, James E. Schneider, J. James Tringali, Roger W. March
  • Patent number: 6992927
    Abstract: An integrated nonvolatile memory circuit having a plurality of control devices. Separate devices execute distinct control, erase, write and read operations, thereby allowing each device to be individually selected and optimized for performing its respective operation.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: January 31, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Pavel Poplevine, Yuri Mirgorodski, Andrew J. Franklin, Hengyang (James) Lin
  • Patent number: 6992925
    Abstract: A programmable memory cell comprised of a transistor located at the crosspoint of a column bitline and a row wordline is disclosed. The transistor has its gate formed from the column bitline and its source connected to the row wordline. The memory cell is programmed by applying a voltage potential between the column bitline and the row wordline to produce a programmed p+ region to form a p-n diode in the substrate underlying the gate of the transistor. Further, the wordline is formed from a buried diffusion N+ layer while the column bitline is formed from a counterdoped polysilicon layer.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: January 31, 2006
    Assignee: Kilopass Technologies, Inc.
    Inventor: Jack Zezhong Peng
  • Patent number: 6984862
    Abstract: A storage device includes a first semiconducting layer having a p-dopant and a second semiconducting layer having an n-dopant, disposed on the first semiconducting layer forming a junction between the first and the second semiconducting layers. The storage device also includes a charge trapping structure disposed on the second semiconducting layer and a conductive gate, wherein the conductive gate and the charge trapping structure move relative to the other, wherein an electric field applied across the second semiconducting layer and the conductive gate traps charge in the charge trapping structure.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: January 10, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Hang Liao, Zhizhang Chen, Alexander Govyadinov, Leslie Louis Szepesi, Jr., Heon Lee
  • Patent number: 6985386
    Abstract: A method of programming a nonvolatile memory cell in which a ramped control voltage is used to obtain the desired voltage on the storage node.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: January 10, 2006
    Assignee: National Semiconductor Corporation
    Inventors: Yuri Mirgorodski, Pavel Poplevine, Peter J. Hopper, Vladislav Vashchenko
  • Patent number: 6977846
    Abstract: A plurality of memory cell arrays are provided. Each of the memory cell arrays has a plurality of memory cells and the memory cells are connected to a plurality of word lines. Corresponding with the plurality of memory cell arrays, a plurality of word line drive circuits and a plurality of bit line control circuits are provided. Each of the word line drive circuits selects and drives the word lines of the corresponding memory cell array. Each of the bit control circuits carries out verifying reading for the data written in advance in the plurality of memory cells of the corresponding memory cell array, and controls a select and driving operation for the word lines of the corresponding word line drive circuit based on a result of the verifying reading.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: December 20, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Kawai, Kenichi Imamiya, Hiroshi Nakamura, Koji Hosono
  • Patent number: 6969662
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate 13. Each of the data storage cells includes a field effect transistor having a source 18, drain 22 and gate 28, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body 22 can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate 28 and the drain 22 and between the source 18 and the drain 22.
    Type: Grant
    Filed: June 5, 2002
    Date of Patent: November 29, 2005
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6965524
    Abstract: In accordance with the present invention, a memory cell includes a non-volatile device and a SRAM cell. The SRAM cell includes first and second MOS transistors. The non-volatile device is a load to the SRAM cell. The memory cell may be adapted to operate differentially if a second SRAM cell and a second non-volatile device is disposed therein. If so adapted, the SRAM cells and/or the non-volatile devices when programmed store and supply complementary data. The non-volatile devices are erased prior to being programmed. Programming of the non-volatile devices may be done via hot-electron injection or Fowler-Nordheim tunneling. When a power failure occurs, the data stored in the SRAM are loaded in the non-volatile devices. After the power is restored, the data stored in the non-volatile devices are restored in the SRAM cells. The differential reading and wring of data reduces over-erase of the non-volatile devices.
    Type: Grant
    Filed: March 19, 2003
    Date of Patent: November 15, 2005
    Assignee: O2IC, Inc.
    Inventor: Kyu Hyun Choi
  • Patent number: 6961279
    Abstract: A non-volatile memory element is operated, in part, in two phases. During the first phase, a voltage is applied to a first node coupled to the nonvolatile memory element to generate an initial voltage. During the second phase, a voltage is coupled through at least one capacitor to charge pump the initial voltage to a level sufficient for programming or erasing the non-volatile memory element.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: November 1, 2005
    Assignee: Linear Technology Corporation
    Inventor: Richard T. Simko
  • Patent number: 6958936
    Abstract: The present invention presents a non-volatile memory and method for its operation that can reduce the amount of disturb in non-selected cells during an erase process. For a set of storage elements formed over a common well structure, all word-lines are initially charged with the same high voltage erase signal that charges the well to insure there is no net voltage difference between the well and word-lines. The selected word-lines are then discharged to ground while the non-selected word-lines and the well are maintained at the high voltage. According to another aspect of the present invention, this can be accomplished without increasing any pitch area circuit or adding new wires in the memory array, and at minimal additional peripheral area. Advantages include less potential erase disturb in the non-selected storage elements and a tighter erase distribution for the selected elements.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: October 25, 2005
    Assignee: SanDisk Corporation
    Inventors: Khandker N. Quader, Raul-Adrian Cernea
  • Patent number: 6955967
    Abstract: A non-volatile memory (30) comprises nanocrystal memory cells (50, 51, 53). The program and erase threshold voltage of the memory cell transistors (50, 51, 53) increase as a function of the number of program/erase operations. During a read operation, a reference transistor (46) provides a reference current for comparing with a cell current. The reference transistor (46) is made from a process similar to that used to make the memory cell transistors (50, 51, 53), except that the reference transistor (46) does not include nanocrystals. By using a similar process to make both the reference transistor (46) and the memory cell transistors (50, 51, 53), a threshold voltage of the reference transistor (46) will track the threshold voltage shift of the memory cell transistor (50, 51, 53). A read control circuit (42) is provided to bias the gate of the reference transistor (46).
    Type: Grant
    Filed: June 27, 2003
    Date of Patent: October 18, 2005
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Gowrishankar L. Chindalore, Rajesh A. Rao, Jane A. Yater
  • Patent number: 6954381
    Abstract: Novel memory cells utilize source-side injection, allowing very small programming currents. If desired, to-be-programmed cells are programmed simultaneously while not requiring an unacceptably large programming current for any given programming operation. In one embodiment, memory arrays are organized in sectors with each sector being formed of a single column or a group of columns having their control gates connected in common. In one embodiment, a high speed shift register is used in place of a row decoder to serially shift in data for the word lines, with all data for each word line of a sector being contained in the shift register on completion of its serial loading. In one embodiment, speed is improved by utilizing a parallel loaded buffer register which receives parallel data from the high speed shift register and holds that data during the write operation, allowing the shift register to receive serial loaded data during the write operation for use in a subsequent write operation.
    Type: Grant
    Filed: August 20, 2002
    Date of Patent: October 11, 2005
    Assignee: SanDisk Corporation
    Inventors: Daniel C. Guterman, Gheorghe Samachisa, Yupin Kawing Fong, Eliyahou Harari
  • Patent number: 6953964
    Abstract: Rows of memory cells are electrically isolated from one another by trenches formed in the substrate between the rows that are filled with a dielectric, commonly called “shallow trench isolation” or “STI.” Discontinuous source and drain regions of the cells are connected together by column oriented bit lines, preferably made of doped polysilicon, that extend in the column direction on top of the substrate. This structure is implemented in a flash memory array of cells having either one floating gate per cell or at least two floating gates per cell. A process of making a dual-floating gate memory cell array includes etching the word lines twice along their lengths, once to form openings through which source and drain implants are made and in which the conductive bit lines are formed, and second to form individual floating gates with a select transistor gate positioned between them that also serves to erase charge from the adjacent floating gates.
    Type: Grant
    Filed: April 12, 2004
    Date of Patent: October 11, 2005
    Assignee: SanDisk Corporation
    Inventors: Jack H. Yuan, Jacob Haskell
  • Patent number: 6950338
    Abstract: A floating gate transistor has a reduced barrier energy at an interface with an adjacent amorphous silicon carbide (a-SiC) gate insulator, allowing faster charge transfer across the gate insulator at lower voltages. Data is stored as charge on the floating gate. The data charge retention time on the floating gate is reduced. The data stored on the floating gate is dynamically refreshed. The floating gate transistor provides a dense and planar dynamic electrically alterable and programmable read only memory (DEAPROM) cell adapted for uses such as for a dynamic random access memory (DRAM) or a dynamically refreshed flash EEPROM memory. The floating gate transistor provides a high gain memory cell and low voltage operation.
    Type: Grant
    Filed: August 14, 1998
    Date of Patent: September 27, 2005
    Assignee: Micron Technology Inc.
    Inventors: Leonard Forbes, Joseph E. Geusic, Kie Y. Ahn
  • Patent number: 6947325
    Abstract: This invention largely reduces a data writing time of a non-volatile semiconductor memory device. A memory array is split into a first memory cell array to be programmed with normal data in its memory cells and a second memory cell array to be programmed with inverted data of the normal data in its memory cells. A column decoder selects a bit line connected with the memory cell written with the normal data and a bit line connected with the memory cell written with the inverted data simultaneously. A differential amplifier amplifies a difference between signals outputted to the pair of these bit lines and outputs it to an I/O line.
    Type: Grant
    Filed: May 21, 2004
    Date of Patent: September 20, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Yoshinobu Kaneda
  • Patent number: 6937520
    Abstract: In a nonvolatile floating-gate semiconductor memory device, a word line voltage supply circuit is configured to be able to apply gate voltages to the same memory cells such that the gate voltage applied at and after the second time is different from the gate voltage applied at the first time. At least one of the word line voltage supply circuit and the bit line voltage supply circuit is set to be able to apply a voltage to the same memory cells for a longer application period at the first time than at and after the second time. With this configuration, the threshold voltage distribution of the memory cells is controlled to be narrow.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: August 30, 2005
    Inventors: Tsuyoshi Ono, Yasuaki Hirano, Masahiko Watanabe, Sau Ching Wong
  • Patent number: 6937516
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: August 30, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6934191
    Abstract: A nonvolatile semiconductor memory device having a small layout area includes a memory cell array in which a plurality of memory cells are arranged in a row direction and a column direction, wherein each of the memory cells includes a source region, a drain region, a channel region between the source region and the drain region, a word gate and a select gate disposed to face the channel region, and a nonvolatile memory element formed between the word gate and the channel region, wherein the wordline-and-selectline-driver-section includes a plurality of unit wordline-and-selectline-driver-sections, and wherein each of the unit wordline-and-selectline driver sections drives the select gates and the word gates of the memory cells in each row at a single potential.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: August 23, 2005
    Assignee: Seiko Epson Corporation
    Inventor: Kimihiro Maemura
  • Patent number: 6934186
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: August 23, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6930920
    Abstract: A memory cell comprises a multilayer gate heating structure formed over a channel region between source and drain regions. The multilayer gate heating structure comprises polysilicon and metal silicide layers stacked over a similarly shaped gate oxide. When a programming voltage is applied across the metal silicide layer, there is intense localized heating. The heating causes segregation of the channel dopant atoms towards the source and drain regions, lowering the threshold voltage of the device. The heating causes carrier activation in the polysilicon layer and dopant penetration through the oxide layer into the channel region, thereby increasing the threshold voltage of the device.
    Type: Grant
    Filed: October 24, 2003
    Date of Patent: August 16, 2005
    Assignee: Xilinx, Inc.
    Inventor: Kevin T. Look
  • Patent number: 6930918
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: December 1, 2003
    Date of Patent: August 16, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6925006
    Abstract: A semiconductor device, such as a memory device or radiation detector, is disclosed, in which data storage cells are formed on a substrate. Each of the data storage cells includes a field effect transistor having a source, drain, and gate, and a body arranged between the source and drain for storing electrical charge generated in the body. The magnitude of the net electrical charge in the body can be adjusted by input signals applied to the transistor, and the adjustment of the net electrical charge by the input signals can be at least partially cancelled by applying electrical voltage signals between the gate and the drain and between the source and the drain.
    Type: Grant
    Filed: November 28, 2003
    Date of Patent: August 2, 2005
    Assignee: Innovative Silicon S.A.
    Inventors: Pierre Fazan, Serguei Okhonin
  • Patent number: 6914842
    Abstract: An option fuse circuit, which can be viewed as a latch-type option fuse circuit, is manufactured with a standard single-poly CMOS manufacturing process. The option fuse circuit includes a non-volatile memory module for storing a logic bit in a data program status, a data control circuit electrically connected to the non-volatile memory module for controlling operations of the option fuse circuit, and an output circuit electrically connected to the data control circuit for outputting the logic data bit in a data read status.
    Type: Grant
    Filed: July 2, 2003
    Date of Patent: July 5, 2005
    Assignee: eMemory Technology Inc.
    Inventors: Chong-Jen Huang, Yu-Ming Hsu, Jie-Hau Huang
  • Patent number: 6911370
    Abstract: A non-volatile memory device includes a substrate having a first active region and a second active region. A first floating gate is provided over the first active region and having an edge, the first floating gate being made of a conductive material. A first spacer is connected to the edge of the first floating gate and being made of the same conductive material as that of the first floating gate. A control gate is provided proximate to the floating gate.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: June 28, 2005
    Assignee: Hynix Semiconductor, Inc.
    Inventors: Hsingya Arthur Wang, Kai-Cheng Chou, Peter Rabkin
  • Patent number: 6903978
    Abstract: A method of programming a PMOS stacked gate memory cell is provided that utilizes a sequence of control gate pulses to obtain the desired potential on the floating gate.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: June 7, 2005
    Assignee: National Semiconductor Corporation
    Inventors: Yuri Mirgorodski, Vladislav Vashchenko, Peter J. Hopper
  • Patent number: 6898120
    Abstract: A memory cell array of a nonvolatile semiconductor memory device includes a plurality of memory cells disposed in a row direction and a column direction. The memory cell array includes a plurality of word lines. Each of the memory cells includes a source region and a drain region. Each of the memory cells includes a select gate and a word gate which are disposed to face a channel region between the source region and the drain region. Each of the memory cells includes a nonvolatile memory element formed between the word gate and the channel region. The word line drive section includes a plurality of unit word line drive sections. Each of the unit word line driver sections drives two of the word lines connected respectively with two of the word gates adjacent to each other in the column direction.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: May 24, 2005
    Assignee: Seiko Epson Corporation
    Inventor: Kanji Natori
  • Patent number: 6898116
    Abstract: A programmable memory cell comprised of a transistor located at the crosspoint of a column bitline and a row wordline is disclosed. The transistor has its gate formed from the column bitline and its source connected to the row wordline. The memory cell is programmed by applying a voltage potential between the column bitline and the row wordline to produce a programmed n+ region in the substrate underlying the gate of the transistor. Further, the row wordline is formed from a buried N+ layer allowing for higher density integration.
    Type: Grant
    Filed: October 2, 2003
    Date of Patent: May 24, 2005
    Assignee: Kilopass Technologies, Inc.
    Inventor: Jack Zezhong Peng