Abstract: A nonvolatile memory device has a combination of FLOTOX EEPROM nonvolatile memory arrays. Each FLOTOX-based nonvolatile memory array is formed of FLOTOX-based nonvolatile memory cells that include at least one floating gate tunneling oxide transistor such that a coupling ratio of the control gate to the floating gate of the floating gate tunneling oxide transistor is from approximately 60% to approximately 70% and a coupling ratio of the floating gate to the drain region of the floating gate tunneling oxide transistor is maintained as a constant of is from approximately 10% to approximately 20% and such that a channel length of the channel region is decreased such that during the programming procedure a negative programming voltage level is applied to the control gate and a moderate positive programming voltage level is applied to the drain region to prevent the moderate positive programming voltage level from exceeding a drain-to-source breakdown voltage.

Abstract: A novel NVM-based 2T or 2nT NAND-cell for a NAND-array for PLD, PAL and matching functions is disclosed. The preferable NVM cell can be ROM or Flash. The 2T flash cell preferably uses FN for both program and erase operation, while 2T ROM cell preferably to use phosphorus for ROM code implant to get negative Vt0.

Abstract: This invention discloses circuit and methods of a NAND-based 2T-string NOR flash cell structure as a building block for a fast random-read NOR flash memory. The key concept of this new set of bias conditions in cell array improves over the critical concern of punch-through issue when cell is migrating to the more advanced technology node of next generation. The invention adopts a novel preferable symmetrical 2T-string NOR flash cell. Each NAND or NAND like cell of this 2T-string NOR cell is to store 2 bits and is preferable to be made of N-channel device. The cell is preferable to use Fowler-Nordheim Tunneling scheme for both erase and program operations. The invention is to provide a novel 2T-string NOR flash cell structure made of N-channel device offering most flexible erase sizes in unit of byte, page, sector, block and chip with the least program and erase disturbances.

Abstract: A nonvolatile memory device has a combination of FLOTOX EEPROM nonvolatile memory arrays. Each FLOTOX-based nonvolatile memory array is formed of FLOTOX-based nonvolatile memory cells that include at least one floating gate tunneling oxide transistor such that a coupling ratio of the control gate to the floating gate of the floating gate tunneling oxide transistor is from approximately 60% to approximately 70% and a coupling ratio of the floating gate to the drain region of the floating gate tunneling oxide transistor is maintained as a constant of is from approximately 10% to approximately 20% and such that a channel length of the channel region is decreased such that during the programming procedure a negative programming voltage level is applied to the control gate and a moderate positive programming voltage level is applied to the drain region to prevent the moderate positive programming voltage level from exceeding a drain-to-source breakdown voltage.

Abstract: A two transistor NOR flash memory cell has symmetrical source and drain structure manufactured by a NAND-based manufacturing process. The flash cell comprises a storage transistor made of a double-poly NMOS floating gate transistor and an access transistor made of a double-poly NMOS floating gate transistor, a poly1 NMOS transistor with poly1 and poly2 being shorted or a single-poly poly1 or poly2 NMOS transistor. The flash cell is programmed and erased by using a Fowler-Nordheim channel tunneling scheme. A NAND-based flash memory device includes an array of the flash cells arranged with parallel bit lines and source lines that are perpendicular to word lines. Write-row-decoder and read-row-decoder are designed for the flash memory device to provide appropriate voltages for the flash memory array in pre-program with verify, erase with verify, program and read operations in the unit of page, block, sector or chip.

Abstract: A nonvolatile memory device includes multiple independent nonvolatile memory arrays that concurrently for parallel reading and writing the nonvolatile memory arrays. A parallel interface communicates commands, address, device status, and data between a master device and nonvolatile memory arrays for concurrently reading and writing of the nonvolatile memory arrays and sub-arrays. Data is transferred on the parallel interface at the rising edge and the falling edge of the synchronizing clock. The parallel interface transmits a command code and an address code from a master device and transfers a data code between the master device and the nonvolatile memory device, wherein the data code has a length that is determined by the command code and a location determined by the address code. Reading one nonvolatile memory array may be interrupted for reading another. One reading operation has two sub-addresses with one transferred prior to a command.

Abstract: Methods of increasing the speed of random read and write operations of a memory device are provided for improving the performance of volatile and non-volatile memory devices. In contrast to the conventional approach that latches the current memory address right before the currently accessed memory data are outputted, the methods latch the next memory address before the currently accessed memory data are read out. The flow, timing waveforms and control sequences of applying the methods to parallel NOR flash, parallel pSRAM, serial SQI NOR flash and NAND flash are described in detail. The NOR flash device designed with the method can be integrated with a NAND flash device on a same die in a combo flash device packaged in either an ONFI compatible NAND flash package or other standard NAND flash package.

Abstract: A single polycrystalline silicon floating gate nonvolatile memory device has a storage MOS transistor and at least one polycrystalline-insulator-polycrystalline (PIP) or metal-insulator-metal (MIM) capacitor manufactured with dimensions that can be fabricated using current low voltage logic integrated circuit process. The PIP or MIM capacitor is a coupling capacitor with a first plate connected to a floating gate of the storage MOS transistor to form a floating gate node. The coupling PIP or MIM capacitor couples the voltage level applied to a second plate of the PIP or MIM capacitor to the floating gate node with a large coupling ratio approximately 90% so as to initiate Fowler-Nordheim tunneling effect for erasing or programming the memory device. The memory device may also have another PIP or MIM capacitor with a first plate connected to the floating gate of the storage MOS transistor for serving as a tunneling capacitor.

Abstract: A DRAM-like non-volatile memory array includes a cell array of non-volatile cell units with a DRAM-like cross-coupled latch-type sense amplifier. Each non-volatile cell unit has two non-volatile cell devices with respective bit lines and source lines running in parallel and laid out perpendicular to the word line associated with the non-volatile cell unit. The two non-volatile cell devices are programmed with erased and programmed threshold voltages as a pair for storing a single bit of binary data. The two bit lines of each non-volatile cell unit are coupled through a Y-decoder and a latch device to the two respective inputs of the latch-type sense amplifier which provides a large sensing margin for the cell array to operate properly even with a narrowed threshold voltage gap. Each non-volatile cell device may be a 2T FLOTOX-based EEPROM cell, a 2T flash cell, 1 1T flash cell or a 1.5T split-gate flash cell.

Abstract: An integrated circuit formed of nonvolatile memory array circuits, logic circuits and linear analog circuits is formed on a substrate. The nonvolatile memory array circuits, the logic circuits and the linear analog circuits are separated by isolation regions formed of a shallow trench isolation. The nonvolatile memory array circuits are formed in a triple well structure. The nonvolatile memory array circuits are NAND-based NOR memory circuits formed of at least two floating gate transistors that are serially connected such that at least one of the floating gate transistors functions as a select gate transistor to prevent leakage current through the charge retaining transistors when the charge retaining transistors is not selected for reading. Each column of the NAND-based NOR memory circuits are associated with and connected to one bit line and one source line.

Abstract: A NAND-based NOR flash memory array has a matrix of NAND-based NOR flash cells arranged in rows and columns. Every two adjacent NAND-based NOR flash cells in a column share a common source node which is connected to a common source line through a diode. The source line may be made of a metal layer and is in contact directly with the source node or through an ohmic contact to form a Schottky barrier diode. The source line may also be made of a polysilicon or metal layer and connected to the source node through a pillar-structured polysilicon diode and a conduction layer. The diode may also be formed in the source node by enclosing a P/N+ junction diode in a heavily N+ doped region of the source node.

Abstract: A single polycrystalline silicon floating gate nonvolatile memory cell has a MOS capacitor and a storage MOS transistor fabricated with dimensions that allow fabrication using current low voltage logic integrated circuit process. The MOS capacitor has a first plate connected to a gate of the storage MOS transistor to form a floating gate node. The physical size of the MOS capacitor is relatively large (approximately 10 time greater) when compared to a physical size of the storage MOS transistor to establish a large coupling ratio (greater than 80%) between the second plate of the MOS capacitor and the floating gate node. When a voltage is applied to the second plate of the MOS capacitor and a voltage applied to the source region or drain region of the MOS transistor establishes a voltage field within the gate oxide of the MOS transistor such that Fowler-Nordheim edge tunnel is initiated.

Abstract: Two-transistor FLOTOX EEPROM cells are collected to form an alterable unit such as a byte. Each of the two-transistor FLOTOX EEPROM cells has a bit line connected to a drain of a select transistor of each of the two-transistor FLOTOX EEPROM cells and a source line placed in parallel with the bit line and connected to a source of a floating gate transistor of each of the two-transistor FLOTOX EEPROM cells. In a program operation, the bit lines are connected to a very large programming voltage level and the source lines are connected to a punch through inhibit voltage level. The punch through inhibit voltage level is approximately one half the very large programming voltage level. The lower drain-to-source voltage level permits the select transistor and the floating gate transistor to have smaller channel lengths and therefore a lower drain-to-source breakdown voltage.

Abstract: An integrated circuit formed of nonvolatile memory array circuits, logic circuits and linear analog circuits is formed on a substrate. The nonvolatile memory array circuits, the logic circuits and the linear analog circuits are separated by isolation regions formed of a shallow trench isolation. The nonvolatile memory array circuits are formed in a triple well structure. The nonvolatile memory array circuits are NAND-based NOR memory circuits formed of at least two floating gate transistors that are serially connected such that at least one of the floating gate transistors functions as a select gate transistor to prevent leakage current through the charge retaining transistors when the charge retaining transistors is not selected for reading. Each column of the NAND-based NOR memory circuits are associated with and connected to one bit line and one source line.

Abstract: A method and apparatus for operation for the NAND-like dual charge retaining transistor NOR flash memory cells begins by erasing, verifying over-erasing the threshold voltage level of the erased charge retaining transistors to an erased threshold voltage level. Then method progresses by programming one of two charge retaining transistors of the NAND-like dual charge retaining transistor NOR flash memory cells to a first programmed threshold voltage level, and programming the other of the two charge retaining transistors of the NAND-like dual charge retaining transistor NOR flash memory cells to the first programmed threshold voltage level or to a second programmed threshold voltage level. Combinations of the erased threshold voltage level and the first and second programmed threshold voltage levels determine an internal data state of the NAND-like dual charge retaining transistor NOR flash memory cells which are then decoded to ascertain the external data logical state.

Abstract: A NOR flash nonvolatile memory or reconfigurable logic device has an array of NOR flash nonvolatile memory circuits that includes charge retaining transistors serially connected in a NAND string such that at least one of the charge retaining transistors functions as a select gate transistor to prevent leakage current through the charge retaining transistors when the charge retaining transistors is not selected for reading. The topmost charge retaining transistor's drain is connected to a bit line parallel to the charge retaining transistors and the bottommost charge retaining transistor's source is connected to a source line and is parallel to the bit line. The charge retaining transistors are programmed and erased with a Fowler-Nordheim tunneling process.

Abstract: A nonvolatile memory structure with pairs of serially connected threshold voltage adjustable select transistors connected to the top and optionally to the bottom of NAND series strings of groups of the dual-sided charge-trapping nonvolatile memory cells for controlling connection of the NAND series string to an associated bit line. A first of the threshold voltage adjustable select transistors has its threshold voltage level adjusted to a first threshold voltage level and a second of the threshold voltage adjustable select transistors adjusted to a second threshold voltage level. The pair of serially connected threshold voltage adjustable select transistors is connected to a first of two associated bit lines. The NAND nonvolatile memory strings further is connected to a pair of serially connected threshold voltage adjustable bottom select transistors that is connected to the second associated bit line.

Abstract: A nonvolatile SRAM circuit has an SRAM cell and one or two FLOTOX EEPROM cells connected to the data storage terminals of the SRAM cell. In programming to a first data level, the threshold voltage of a FLOTOX EEPROM transistor is brought to a programmed voltage level greater than a read voltage level and erasing to a second data level, the threshold voltage of the FLOTOX EEPROM transistor is brought to an erased voltage level less than the read voltage level. The nonvolatile SRAM array provides for restoring data to an SRAM cell from a FLOTOX EEPROM memory cell(s) at a power initiation and storing data to the FLOTOX EEPROM memory cell(s) to the SRAM cell at power termination. A power detection circuit for providing signals indicating power initiation and power termination to instigate restoration and storing of data between an SRAM cell and a FLOTOX EEPROM cell(s).

Abstract: A two transistor NOR flash memory cell has symmetrical source and drain structure manufactured by a NAND-based manufacturing process. The flash cell comprises a storage transistor made of a double-poly NMOS floating gate transistor and an access transistor made of a double-poly NMOS floating gate transistor, a poly1 NMOS transistor with poly1 and poly2 being shorted or a single-poly poly1 or poly2 NMOS transistor. The flash cell is programmed and erased by using a Fowler-Nordheim channel tunneling scheme. A NAND-based flash memory device includes an array of the flash cells arranged with parallel bit lines and source lines that are perpendicular to word lines. Write-row-decoder and read-row-decoder are designed for the flash memory device to provide appropriate voltages for the flash memory array in pre-program with verify, erase with verify, program and read operations in the unit of page, block, sector or chip.

Abstract: A nonvolatile memory device includes an array of EEPROM configured nonvolatile memory cells each having a floating gate memory transistor for storing a digital datum and a floating gate select transistor for activating the floating gate memory transistor for reading, programming, and erasing. The nonvolatile memory device has a row decoder to transfer the operational biasing voltage levels to word lines connected to the floating gate memory transistors for reading, programming, verifying, and erasing the selected nonvolatile memory cells. The nonvolatile memory device has a select gate decoder circuit transfers select gate control biasing voltages to the select gate control lines connected to the control gate of the floating gate select transistor for reading, programming, verifying, and erasing the floating gate memory transistor of the selected nonvolatile memory cells.