A non-volatile memory includes a cell array, a current supply circuit, a path selecting circuit, a verification circuit and a control circuit. During a sample period of a verification action, the control circuit controls the current supply circuit to provide n M-th reference currents to the verification circuit and convert the n M-th reference currents into n reference voltages. During a verification period of the verification action, the control circuit controls n multi-level memory cells of a selected row of the cell array to generate n cell currents to the verification circuit and convert the n cell currents into n sensed voltages. The n verification devices generate the n verification signals according to the reference voltages and the sensed voltages. Accordingly, the control circuit judges whether the n multi-level memory cells have reached an M-th storage state.

In a non-volatile memory, a block of NAND strings is divided into sub-blocks by etching the select gate layers between sub-blocks. This results in a subset of NAND strings (e.g., at the border of the sub-blocks) having select gates that are partially etched such that the partially etched select gates are partially shaped as compared to the select gates of NAND strings that have not been etched. Host data is programmed to non-volatile memory cells that are connected to an edge word line and are on NAND strings having a complete shaped select gate. Host data is also programmed to non-volatile memory cells that are connected to non-edge word lines. However, host data is not programmed to non-volatile memory cells that are connected to the edge word line and are on NAND strings having a partial shaped select gate.

A semiconductor memory cell includes a floating body region configured to be charged to a level indicative of a state of the memory cell; a first region in electrical contact with said floating body region; a second region in electrical contact with said floating body region and spaced apart from said first region; and a gate positioned between said first and second regions. The cell may be a multi-level cell. Arrays of memory cells are disclosed for making a memory device. Methods of operating memory cells are also provided.

A storage apparatus includes an interface and storage circuitry. The interface communicates with a plurality of memory cells, and an individual one of the plurality of memory cells stores data in multiple programming levels. The storage circuitry configured to program data to a first group of multiple memory cells in a number of programming levels larger than two, using a One-Pass Programming (OPP) scheme that results in a first readout reliability level. After programming the data, the storage circuitry is further configured to read the data from the first group, and program the data read from the first group to a second group of the memory cells, in a number of programming levels larger than two, using a Multi-Pass Programming (MPP) scheme that results in a second readout reliability higher than the first reliability level, and reading the data from the second group of the memory cells.

A storage apparatus includes an interface and storage circuitry. The interface communicates with a plurality of memory cells, and an individual one of the plurality of memory cells stores data in multiple programming levels. The storage circuitry configured to program data to a first group of multiple memory cells in a number of programming levels larger than two, using a One-Pass Programming (OPP) scheme that results in a first readout reliability level. After programming the data, the storage circuitry is further configured to read the data from the first group, and program the data read from the first group to a second group of the memory cells, in a number of programming levels larger than two, using a Multi-Pass Programming (MPP) scheme that results in a second readout reliability higher than the first reliability level, and reading the data from the second group of the memory cells.

A nonvolatile semiconductor memory device comprises a cell unit including a first and a second selection gate transistor and a memory string provided between the first and second selection gate transistors and composed of a plurality of serially connected electrically erasable programmable memory cells operative to store effective data; and a data write circuit operative to write data into the memory cell, wherein the number of program stages for at least one of memory cells on both ends of the memory string is lower than the number of program stages for other memory cells, and the data write circuit executes the first stage program to the memory cell having the number of program stages lower than the number of program stages for the other memory cells after the first stage program to the other memory cells.

A method of operating a memory device that includes a plurality of stages each having a plurality of page buffers. The method including performing a verify operation of a first program loop from among a plurality of program loops, the verify operation of the first program loop including, performing a first off-cell counting operation on a first stage of the plurality of stages based on a first sampling rate to generate a first off-cell counting result; selectively changing the first sampling rate based on the first off-cell counting result to generate a changed first sampling rate; and performing a second off-cell counting operation on a second stage of the plurality of stages based on one of the first sampling rate and the changed first sampling rate to generate a second off-cell counting result.

A nonvolatile semiconductor memory device includes a control circuit configured to control a soft program operation of setting nonvolatile memory cells to a first threshold voltage distribution state of the nonvolatile memory cells. When a characteristic of the nonvolatile memory cells is in a first state, the control circuit executes the soft program operation by applying a first voltage for setting the nonvolatile memory cells to the first threshold voltage distribution state to first word lines, and applying a second voltage higher than the first voltage to a second word line. When the characteristic of the nonvolatile memory cells is in a second state, the control circuit executes the soft program operation by applying a third voltage equal to or lower than the first voltage to the first word lines and applying a fourth voltage lower than the second voltage to the second word line.

An operating method is for a memory device which controls a nonvolatile memory. The operating method includes managing a program depth bit map indicating an upper page program state of each of a plurality of word lines of the nonvolatile memory in response to an external write request, and outputting one of a plurality of different read commands to the nonvolatile memory based on information of the program depth bit map corresponding to a word line to be accessed in response to an external read request.

Methods, systems, and devices for preventing disturb of untargeted memory cells during repeated access operations of target memory cells are described for a non-volatile memory array. Multiple memory cells may be in electronic communication with a common conductive line, and each memory cell may have an electrically non-linear selection component. Following an access operation (e.g., a read or write operation) of a target memory cell, untargeted memory cells may be discharged by applying a discharge voltage to the common conductive line. The discharge voltage may, for example, have a polarity opposite to the access voltage. In other examples, a delay may be instituted between access attempts in order to discharge the untargeted memory cells.