Silicon Storage Technology, Inc.

Cypress Semiconductor Corporation

Spansion Llc.

Longitude Flash Memory Solutions Ltd.

Ya-Fen Lin

Dana Lee

Changyuan Chen

Youseok Suh

Yuniarto Widjaja

John W Cooksey

Feng Gao

Yi-Ching Jean Wu

Sung-Yong Chung

Bomy A Chen

Takao Akaogi

Colin Stewart Bill

Jack Frayer

Zhitang Song

Songlin Feng

Elbert Lin

Hieu Van Tran

Hung Quoc Nguyen

William Saiki

Coling Stewart Bill

Gianfranco Pellegrini

Xiuhong Chen

A memory device is described. Generally, the device includes a string of memory transistors, a source select transistor coupled to a first end of the string of memory transistor and a drain select transistor coupled to a second end of the string of memory transistor. Each memory transistor includes a gate electrode formed adjacent to a charge trapping layer and there is neither a source nor a drain junction between adjacent pairs of memory transistors or between the memory transistors and source select transistor or drain select transistor. In one embodiment, the memory transistors are spaced apart from adjacent memory transistors and the source select transistor and drain select transistor, such that channels are formed therebetween based on a gate fringing effect associated with the memory transistors. Other embodiments are also described.

Gate fringing effect based channel formation for semiconductor device

A split gate NAND flash memory structure is formed on a semiconductor substrate of a first conductivity type. The NAND structure comprises a first region of a second conductivity type in the substrate with a second region of the second conductivity type in the substrate, spaced apart from the first region. A continuous first channel region is defined between the first region and the second region. A plurality of floating gates are spaced apart from one another with each positioned over a separate portion of the channel region. A plurality of control gates are provided with each associated with and adjacent to a floating gate. Each control gate has two portions: a first portion over a portion of the channel region and a second portion over the associated floating gate and capacitively coupled thereto.

Method of programming a continuous-channel flash memory device

Methods and structures for forming semiconductor channels based on gate fringing effect are disclosed. In one embodiment, a NAND flash memory device comprises multiple NAND strings of memory transistors. Each memory transistor includes a charge trapping layer and a gate electrode formed on the charge trapping layer. The memory transistors are formed close to each other to form a channel between an adjacent pair of the memory transistors based on a gate fringing effect associated with the adjacent pair of the memory transistors.

A memory system is programmed with minimal program disturb and reduced junction and channel leakage during self-boosting. Pre-charging bias signals are applied to word lines adjacent to a selected word line before a program signal is applied to the selected word line and a pass signal is applied to the remaining word lines. The pre-charging bias signals apply a pre-charge to the memory cells. The pre-charging bias signals are chosen to improve the isolation of the memory cells on word lines adjacent to the selected word line, improve self boost efficiency and reduce current leakage to prevent or reduce program disturb and/or programming errors especially in the inhibited memory cells on the selected word line.

Partial local self boosting for NAND

Split gate NAND flash memory structure and array, method of programming, erasing and reading thereof, and method of manufacturing

Nonvolatile flash memory systems and methods are disclosed having a semiconductor substrate of a first conductivity type, including non-diffused channel regions through which electron flow is induced by application of voltage to associated gate elements. A plurality of floating gates are spaced apart from one another and each insulated from the channel region. A plurality of control gates are spaced apart from one another and insulated from the channel region, with each control gate being located between a first floating gate and a second floating gate and capacitively coupled thereto to form a subcell. A plurality of spaced-apart assist gates are insulated from the channel region, with each assist gate being located between and insulated from adjacent subcells. The channel is formed of three regions, two beneath adjacent control gate elements as well as a third region between the first two and beneath an associated assist gate.

Non-diffusion junction split-gate nonvolatile memory cells and arrays, methods of programming, erasing, and reading thereof, and methods of manufacture

A method for partial local self-boosting of a memory cell channel is disclosed. As a part of memory cell channel partial local self-boosting, an isolating memory cell located on a source side of a program inhibited memory cell is turned off and a gating memory cell located on a drain side of the program inhibited memory cell is used to pass a pre-charge voltage to the program inhibited memory cell to provide a pre-charge voltage to a channel of the program inhibited memory cell. Moreover, a pre-charge voltage is passed to a buffering memory cell located on the source side of the program inhibited memory cell to provide a pre-charge voltage to a channel of the buffering memory cell and the gating memory cell that is located on the drain side of the program inhibited memory cell is turned off. During programming, a program voltage is applied to the gate of the program inhibited memory cell where a channel voltage of the program inhibited memory cell is raised above a level raised by the pre-charge voltage.

Partial local self-boosting of a memory cell channel

A method and apparatus for dynamic programming and dynamic reading of a select non-volatile memory cell in a virtual grounds array is disclosed. In the dynamic read operation the global bit lines and the associated local bit lines are connected to a precharged voltage. One of the first or second global bit lines is connected to a low voltage such as ground, wherein the one global bit line connected to ground also connects to the local bit line for sensing the select non-volatile memory cell. The state of the select non-volatile memory cell is detected by detecting the sense amplifier connected to the global bit line, other than the one global bit line. In a dynamic programming operation, the first and second global bit lines and their associated local bit lines are precharged to a first voltage. One of the first or second global bit line and its associated local bit lines is connected to a second voltage.

Method and apparatus for reading and programming a non-volatile memory cell in a virtual ground array

A method of trimming down the volume of a semiconductor resistor element using electrical resistance feedback. After forming conductive material disposed between a pair of electrodes, a voltage is applied to the electrodes to produce an electrical current through the conductive material sufficient to heat and melt away a portion of the conductive material. By reducing the volume of the conductive material, its resistance is increased. The application of the voltage is ceased once the desired dimensions (and thus resistivity) of the conductive material is reached. The resulting semiconductor resistor element could have a fixed resistance, or could have a variable resistance (by using phase change memory material).

Method of trimming semiconductor elements with electrical resistance feedback

Growing community of inventors

Santa Clara, CA, United States of America

Ya-Fen Lin