Atmel Corporation

Advanced Micro Devices Corporation

Steven J Schumann

Anil Gupta

Tsung-Ching Wu

Fai Ching

Sai Kai Tsang

Geeng-Chuan Chern

Philip S Ng

Vikram Kowshik

James C Hu

George Smarandoiu

Nicola Telecco

Jason Guo

Edward S Hui

Vijay P Adusumilli

John Y Huang

Kent D Lewallen

Yolanda Yuan

A memory device comprises memory cells arranged in rows and columns, and source lines associated with memory sections, each of which includes a plurality of memory cells. Source terminals of transistors included in the memory cells in a first memory section are physically coupled to a first source line that is distinct from other source lines associated with other memory sections on a same row of the memory device as the first memory section. Gate terminals of transistors included in memory cells in a row share a common wordline configured for providing a signal to the gate terminals.

Memory device and systems and methods for selecting memory cells in the memory device

Selecting memory cells using source lines

A nonvolatile memory apparatus includes a separate controller circuit and memory circuit. The controller circuit is fabricated on a first integrated circuit chip. The controller circuit includes a plurality of charge pump circuits, a system interface logic circuit, a memory control logic circuit, and one or more analog circuits. The memory circuit is fabricated on a second integrated circuit chip and includes a column decoder, a row decoder, a control register, and a data register. A memory-controller interface area includes a first plurality of die bond pads on the first integrated circuit chip and a second plurality of die bond pads on the second integrated circuit chip such that the first and second integrated circuit chips may be die-bonded together. A single controller circuit may interface with a plurality of memory circuits, thus further reducing overall costs as each memory circuit does not require a dedicated controller circuit.

Nonvolatile semiconductor memory apparatus

An apparatus and method identify a plurality of words to be read, read these selected words during a clock latency period, and then shift these words out synchronously at an end of the latency period. In another aspect of the present invention, the above method of reading a plurality of words during a clock latency period and shifting them out synchronously after the latency period is facilitated by a two tier column decoder. The two-tier column decoder has two decoders. A first-tier decoder decodes a first group of words to be read during the latency period, and a second-tier decoder decodes subsequent words to be shifted out synchronously during a burst period.

Method and apparatus of a smart decoding scheme for fast synchronous read in a memory system

A decoding system for multi-plane memories routes address information corresponding to distinct memory access operations to the designated planes. The system includes an array of functional registers dedicated to random access read, burst read, program, erase, and erase-suspend program operations. Plane selector blocks for each plane receive the address outputs from all of the registers and plane function select logic controls the routing in accord with memory access commands for specified planes. Simultaneous operations of different type in different planes and nested operations in the same plane are possible.

Functional register decoding system for multiple plane operation

Group erasing system for flash array with multiple sectors

In a sector in a flash memory array PAGE ERASE and MULTIPLE PAGE ERASE modes of operation are provided. In the PAGE ERASE and MULTIPLE PAGE ERASE modes of operation, a preferred tunneling potential of approximately &minus;10 Volts is applied to the gates of the flash memory cells on the row or rows being selected for erasure, and the bitlines connected to the drains of the flash memory cells are driven to a preferred voltage of approximately 6.5 Volts. To reduce the unintended erasure of memory cells in rows other than the selected row or rows, a preferred bias voltage of approximately 1 to 2 Volts is applied to the gates of all the flash memory cells in the rows other than the selected row or rows.

Page mode erase in a flash memory array

In a sector in a flash memory array PAGE ERASE and MULTIPLE PAGE ERASE modes of operation are provided. In the PAGE ERASE and MULTIPLE PAGE ERASE modes of operation, a preferred tunneling potential of approximately -10 Volts is applied to the gates of the flash memory cells on the row or rows being selected for erasure, and the bitlines connected to the drains of the flash memory cells are driven to a preferred voltage of approximately 6.5 Volts. To reduce the unintended erasure of memory cells in rows other than the selected row or rows, a preferred bias voltage of approximately 1 to 2 Volts is applied to the gates of all the flash memory cells in the rows other than the selected row or rows.

A flash memory array architecture comprising a flash memory array, first and second memory buffer, and I/O interface circuit which has several operating modes which permit data to be read from the flash memory array, several operating modes which permit data to be programmed into the flash memory array, and a mode for rewriting the data in the flash memory array. In the four read modes, one of the pages stored in the flash memory array is read, the data stored in either of first or second memory buffers is read, the data in one of the pages of data stored in the flash memory array is read and then written into either of first or second memory buffers, the data in one of the pages of data stored in the flash memory array is read and then compared to the data read from either of first or second memory buffers. In the four write modes, data from an input stream is written into a selected first or second memory buffer, one of the pages of data stored in the flash memory array is erased, and then in the same cycle, data in either of first or second memory buffers is written into the erased page in the flash memory array, data in either of first or second memory buffers is written into a previously erased page in the flash memory array, and data from an input stream is written into the selected first or second memory buffer, one of the pages of data stored in the flash memory array is erased, and then in the same cycle, data in either of first or second memory buffers is written into the erased page in the flash memory array. In the auto page rewrite mode, the data in one of the pages of data stored in the flash memory array is read and then written into either of first or second memory buffers. The data stored in the page of the flash memory array just read is erased, and then in the same cycle, the page of data stored in the selected first or second memory buffer is written into the erased page in the flash memory array.

Dual buffer flash memory architecture with multiple operating modes

A nonvolatile memory device includes two floating-gate-type memory arrays, e.g. a flash memory intended to be used as a relatively permanent program memory and an E.sup.2 PROM intended to be used as a more frequently updated data memory. A single set of address lines and a single set of data lines are used for both read and write operations for both memory arrays. Address decoding means for accessing an addressed location of a selected memory array includes separate column decoders and data latches for each array, but also includes a shared row decoder common to both arrays. Row address latching circuitry associated with at least the data memory holds a decoded row address for that memory array during a write operation so as to free the shared row decoder for use on one or more concurrent read operations for the other memory array, e.g. the program memory. Data I/O buffer circuitry and sense amplifiers are also shared by both arrays. Control logic, responsive to input control signals selecting one of the memory arrays and selecting a read or write operation, controls the various elements of the device, including address and data latches and select/driver circuitry, to carry out the desired operations.

Combined program and data nonvolatile memory with concurrent

Non-volatile semiconductor core memory performance is enhanced by reduced stress on core memory cells. Stress is reduced by selectable application of bias voltages to the sense line under control of the word line. The word line is connected to an inverting device in turn connected to a transistor effective for grounding the gate of a variable threshold programmable transistor in the memory cell. Power down of the word line is reflected in synchronous power-down of the sense line. Additionally, with power down, the sense amplifier for the particular core memory cell is disconnected from a master latch circuit, which in turn is connected to a slave latch circuit for applying the previous sense amplifier output to an input/output buffer, in order to secure the data sensed in core memory during read operation. The invention further permits reduced word line voltages during erase operation on the sense line and the variable threshold programmable transistor.

Stress reduction for non-volatile memory cell

An EEPROM design featuring narrow linear electrodes including a source, a drain, a thin oxide, channel and floating gate. A pair of linear, opposed field oxide barrier walls form widthwise boundaries of the active structure which can be very closely spaced. The drain electrode, implanted in the substrate, abuts both opposed field oxide lateral walls, but does not extend under either wall. The source, drain and channel are formed in a single implant followed by diffusion after the field oxide barrier walls are formed, but prior to formation of the floating gate. All but opposed field oxide walls in a stripe design. A control gate is disposed over the floating gate. The combination of opposed field oxide barrier walls, a stripe electrode design, and single step implant for electrode formation results in a very compact cell, utilizing a simplified EEPROM process.

Fabricating a narrow width EEPROM with single diffusion electrode

An EEPROM design featuring narrow linear electrodes including a source, a drain, a thin oxide, channel and floating gate. A pair of linear, opposed field oxide barrier walls form widthwise boundaries of the active structure which can be very closely spaced. The drain electrode, implanted in the substrate, abuts both opposed field oxide lateral walls, but does not extend under either wall. The source, drain and channel are formed in a single implant followed by diffusion after the field oxide barrier walls are formed, but prior to formation of the floating gate. All abut opposed field oxide walls in a stripe design. A control gate is disposed over the floating gate. The combination of opposed field oxide barrier walls, a stripe electrode design, and single step implant for electrode formation results in a very compact cell, utilizing a simplified EEPROM process.

Narrow width EEPROM with single diffusion electrode formation

A CMOS fabrication process for EEPROMs having high-breakdown-voltage peripheral transistors in which a single implant step early in the process forms buried implants for both the memory cell's tunnel area source and the high voltage transistor's source and drain areas. The single implant step can be formed either before or after the formation of the channel stops and field oxide around the devices. The floating gate of the memory cell and the gates of the other devices are formed with polysilicon, the gates of the high voltage transistor overlapping the buried implants of its source and drain. The sources and drains of the other peripheral devices are then formed, using their polysilicon gates as a self-aligning mask. This may also include the formation of contact source and drain for the high voltage transistor. The process concludes with the formation of one or two layers of conductive lines connecting to specified drains, sources and gates to form a desired circuit pattern.

Fabrication process for EEPROMS with high voltage transistors

A write-bias gate in the form of an FET is provided for each of the bit-lines. Each FET has its drain electrode connected to logic 1 and its source electrode connected to the bit-line. When one port is writing, the write-bias gates on the other port(s) are driven by a signal which causes them to enter a pass condition, supplying extra current to pull up the bit lines of the non-writing port(s).

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Sunnyvale, CA, United States of America

Steven J Schumann