A non-volatile semiconductor memory device in which, while voltage from a first control line is applied, as a memory gate voltage, to a sub control line through a switching transistor, another switching transistor can block voltage application to a corresponding sub control line. Thus, while a plurality of memory cells are arranged in one direction along the first control line, the number of memory cells to which a memory gate voltage is applied can reduced by the switching transistor, which reduces the occurrence of disturbance, accordingly. The sub control line to which the memory gate voltage is applied from the first control line is used as the gates of memory transistors, and thus the sub control line and the gates are disposed in a single wiring layer, thereby achieving downsizing as compared to a case in which the sub control line and the gates are disposed in separate wiring layers.

A non-volatile memory system includes one or more control circuits configured to program memory cells and verify the programming. The verifying of the programmed memory cells includes applying one or more voltages to perform boosting of a channel region associated with unselected memory cells, allowing the boosting of the channel region for a portion of time while applying the one or more voltages, preventing/interrupting the boosting of the channel region while applying the one or more voltages for a duration of time based on position of a memory cell selected for verification, applying a compare signal to the memory cell selected for verification, and performing a sensing operation for the memory cell selected for verification in response to the compare signal.

A method is for operating a nonvolatile memory device, the nonvolatile memory device including at least one string connected to a bit line, the at least one string including a plurality of memory cells connected in series, each of the plurality of memory cells being connected to a respective word line among a plurality of word lines and stacked in a direction perpendicular to a substrate. The method includes applying a word line voltage needed for an operation to a first word line among the word lines, applying a recovery voltage higher than a ground voltage to the first word line after the operation, and then floating the first word line.

A device includes a memory and a controller coupled to the memory. The controller is configured to determine a temperature-based value of a search parameter in response to detecting that an error rate of a codeword read from the memory exceeds a threshold error rate. The controller is further configured to iteratively modify one or more memory access parameters associated with reducing temperature-dependent threshold voltage variation and to re-read the codeword using the modified one or more memory access parameters.

Multi-gate NOR flash thin-film transistor (TFT) string arrays are organized as three dimensional stacks of active strips. Each active strip includes a shared source sublayer and a shared drain sublayer that is connected to substrate circuits. Data storage in the active strip is provided by charge-storage elements between the active strip and a multiplicity of control gates provided by adjacent local word-lines. The parasitic capacitance of each active strip is used to eliminate hard-wire ground connection to the shared source making it a semi-floating, or virtual source. Pre-charge voltages temporarily supplied from the substrate through a single port per active strip provide the appropriate voltages on the source and drain required during read, program, program-inhibit and erase operations. TFTs on multiple active strips can be pre-charged separately and then read, programmed or erased together in a massively parallel operation.

The present invention provides a method for access a flash memory module, wherein the method includes the steps of: sending a read command to the flash memory module to read a plurality of memory cells of at least one word line of the flash memory module by using a plurality of read voltages, wherein each memory cell is configured to store a plurality of bits, each memory cell has a plurality of states, the states are used to indicate different combinations of the plurality of bits; obtaining readout information from the flash memory module; analyzing the readout information to determine numbers of the states of the memory cells; determining if the memory cells are balance or unbalance according the numbers of the states of the memory cells to generate a determination result; and referring to the determination result to adjust voltage levels of the plurality of read voltages.

A variety of applications can include memory devices designed to provide stabilization of selector devices in a memory array of the memory device. A selector stabilizer pulse can be applied to a selector device of a string of the memory array and to a memory cell of multiple memory cells of the string with the memory cell being adjacent to the selector device in the string. The selector stabilizer pulse can be applied directly following an erase operation to the string to stabilize the threshold voltage of the selector device. The selector stabilizer pulse can be applied as part of the erase algorithm of the memory device. Additional devices, systems, and methods are discussed.

In a memory array with a cross-point structure, at each cross-point junction a programmable resistive memory element, such as an MRAM memory cell, is connected in series with a threshold switching selector, such as an ovonic threshold switch. The threshold switching selector switches to a conducting state when a voltage above a threshold voltage is applied. When powered down for extended periods, the threshold voltage can drift upward. If the drift is excessive, this can make the memory cell difficult to access and can disturb stored data values when accessed. Techniques are presented to determine whether excessive voltage threshold drift may have occurred, including a read based test and a time based test.

A memory system includes blocks (or other groupings) of memory cells including data memory cells and dummy memory cells. In order to mitigate program disturb or other issues, the memory system applies a gate voltage based on temperature to all or a subset of the dummy memory cells as part of a memory operation.

A semiconductor device includes a transmission and reception circuit and a control circuit. The transmission and reception circuit transmits and receives a signal to and from a semiconductor memory device. The control circuit acquires threshold voltage distribution information of a memory element connected to a word line for read disturb detection to which a second voltage higher than a first voltage applied to an adjacent word line adjacent to a read target word line during a read operation is applied and determines an influence of read disturb based on the threshold voltage distribution information.