Abstract: A nonvolatile memory device includes a nonvolatile memory array including a plurality of charge retaining transistors arranged in rows and columns. The device has a plurality source lines formed in parallel with the bit lines associated with each column. Row decode/driver circuits are connected to blocks of the charge retaining transistors for controlling the application of the necessary read, program, and erase signals. Erase count registers, each of the erase count registers associated with one block of the array of the charge retaining transistors for storing an erase count for the associated block for determining whether a refresh operation is to be executed. Groupings on each column of the array of charge retaining transistors are connected as NAND series strings where each NAND string has a select gating charge retaining transistor connected to the top charge retaining transistor for connecting the NAND series string to the bit lines.

Abstract: A method for fabricating a high temperature integrated circuit includes forming a drain/source diffusion and forming a buried diffusion implant containing the drain/source diffusion in a substrate to separate the drain/source diffusion from the substrate and an edge of a field isolation layer to decreases leakage current occurring with high voltage and high temperature. A nonvolatile memory array driver circuit with multiple driver transistors separated by anti-leakage transistors connected to prevent excess junction leakage current at elevated temperatures. Another nonvolatile memory array driver circuit has a high voltage blocking transistor connected to two anti-leakage transistors connected such that a source of the first anti-leakage transistor is connected to a drain of the high voltage blocking transistor and a drain of the second anti-leakage transistor is connected to prevent excess junction leakage current at elevated temperatures.

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 NOR flash nonvolatile memory device provides the memory cell size and a low current program process of a NAND flash nonvolatile memory device and the fast, asynchronous random access of a NOR flash nonvolatile memory device. The NOR flash nonvolatile memory 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 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 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 2 T FLOTOX-based EEPROM cell, a 2 T flash cell, 11 T flash cell or a 1.5 T split-gate flash cell.

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 pate connected to the floating gate of the storage MOS transistor for serving as a tunneling capacitor.

Abstract: A non-volatile memory array having FLOTOX-based memory cells connected by a plurality of word lines and a plurality of bit lines is disclosed. In the memory array, the FLOTOX-based memory cells in a common word line do not share a common source line. Instead, the FLOTOX-based memory cells associated with a bit line are provided with a source line laid out in parallel with the bit line to avoid punch-through leakage. The FLOTOX-based memory cells may be 2T FLOTOX-based EEPROM cells or 1T FLOTOX-based flash cells. The byte-alterable and page-alterable functions of a 2T EEPROM array and the block-alterable function of a 1T flash array are preserved. In addition, a novel bit-alterable function is added to both 2T FLOTOX-based EEPROM array and 1T FLOTOX-based flash array to reduce the unnecessary high voltage over-stress in a write operation to improve program/erasure endurance cycles.

Abstract: A novel FLASH-based EEPROM cell, decoder, and layout scheme are disclosed to eliminate the area-consuming divided triple-well in cell array and allows byte-erase and byte-program for high P/E cycles. Furthermore, the process-compatible FLASH cell for EEPROM part can be integrated with FLASH and ROM parts so that a superior combo, monolithic, nonvolatile memory is achieved. Unlike all previous arts, the novel combo nonvolatile memory of the present invention of ROM, EEPROM and FLASH or combination of any two is made of one unified, fully compatible, highly-scalable BN+ cell and unified process. In addition, its cell operation schemes have zero array overhead and zero disturbance during P/E operations. The novel combo nonvolatile memory is designed to meet the need in those markets requiring flexible write size in units of bytes, pages and blocks at a lower cost.

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: 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: A nonvolatile memory array has nonvolatile memory cells arranged in rows and columns where each column has a bit line and source line associated with and in parallel with the nonvolatile memory cells. In programming the nonvolatile memory cell, approximately equal program voltage levels are applied to a drain and a source of a selected charge retaining transistor such that the difference in the voltage between the drain and the source of the selected charge retaining transistor is less than a drain to source breakdown voltage of the selected charge retaining transistor to prevent drain-to-source punch through. In programming or erasing the nonvolatile memory cell a control gate and a bulk program voltage level is applied to a control gate and bulk such that the magnitude of the control gate and bulk program voltage levels is less than a breakdown voltage level of peripheral circuitry.

Abstract: A NOR flash memory cell is formed of dual serially connected charge retaining transistors. A drain/source of a first of the dual charge retaining transistors connected to a local bit line and a source/drain of a second of the dual charge retaining transistors connected to a local source line. The drain/sources of the commonly connected dual serially connected charge retaining transistors are connected solely together. The drain/sources and source drains are formed in a diffusion well. In some embodiments, the diffusion well is formed in a deep diffusion well. The dual serially connected charge retaining transistors are N-channel or P-channel charge retaining transistors with the charge retaining layers being either floating gate or SONOS charge trapping layers. Selected charge retaining transistors are programmed by a combination of a band-to-band tunneling and a Fowler-Nordheim tunneling and erased by a Fowler Nordheim tunneling.

Abstract: A novel FLASH-based EEPROM cell, decoder, and layout scheme are disclosed to eliminate the area-consuming divided triple-well in cell array and allows byte-erase and byte-program for high P/E cycles. Furthermore, the process-compatible FLASH cell for EEPROM part can be integrated with FLASH and ROM parts so that a superior combo, monolithic, nonvolatile memory is achieved. Unlike all previous arts, the novel combo nonvolatile memory of the present invention of ROM, EEPROM and FLASH or combination of any two is made of one unified, fully compatible, highly-scalable BN+ cell and unified process. In addition, its cell operation schemes have zero array overhead and zero disturbance during P/E operations. The novel combo nonvolatile memory is designed to meet the need in those markets requiring flexible write size in units of bytes, pages and blocks at a lower cost.

Abstract: A nonvolatile memory device includes multiple independent nonvolatile memory arrays that concurrently for parallel reading and writing the nonvolatile memory arrays. A serial 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 serial interface at the rising edge and the falling edge of the synchronizing clock. The serial 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: 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: A nonvolatile memory device includes multiple independent nonvolatile memory arrays that concurrently for parallel reading and writing the nonvolatile memory arrays. A serial 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 serial interface at the rising edge and the falling edge of the synchronizing clock. The serial 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. An enable signal defines a beginning and termination of a reading or writing operation. Reading one nonvolatile memory array may be interrupted for another operation and then resumed.

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 mask programmable NOR ROM circuit includes serially connected ROM transistors. A drain of a topmost ROM transistor is connected to a bit line and a source of a bottommost ROM transistor is connected to a source line. A source of one ROM transistor is solely connected with a drain of an immediately adjacent ROM transistor. The ROM transistors are programmed by placing a resist mask having openings for selectively modifying a first threshold voltage level of chosen ROM transistors by implanting a threshold voltage modifying impurity. A selected ROM transistor is read by connecting the source line to a sense amplifier circuit and setting the bit line to a read biasing voltage level. The gate of the selected ROM transistor is set to a moderately high read voltage level. The gates of all unselected ROM transistor is set to a very high read voltage level.

Abstract: A memory system includes a NAND flash memory, a NOR flash memory and a SRAM manufactured on a single chip. Both NAND and NOR memories are manufactured by the same NAND manufacturing process and NAND cells. The three memories share the same address bus, data bus, and pins of the single chip. The address bus is bi-directional for receiving codes, data and addresses and transmitting output. The data bus is also bi-directional for receiving and transmitting data. One external chip enable pin and one external output enable pin are shared by the three memories to reduce the number of pins required for the single chip. Both NAND and NOR memories have dual read page buffers and dual write page buffers for Read-While-Load and Write-While-Program operations to accelerate the read and write operations respectively. A memory-mapped method is used to select different memories, status registers and dual read or write page buffers.