An operating method of a memory device including a plurality of strings on a substrate, wherein the plurality of strings include a main string connected to a bit line and a dummy string spaced apart from the bit line, the operating method including: pre-programming the dummy string; and erasing the main string and the dummy string, wherein the pre-programming includes: applying a pre-program voltage to a word line connected to the dummy string; applying a pass voltage to a ground selection line connected to a ground selection transistor of the dummy string; and applying a common source line voltage to a common source line connected to the dummy string.

A storage array includes multiple wordlines of storage cells that can be selectively charged to an erase voltage or an inhibit voltage. Control logic associated with the storage array can perform erase verify in stages. On a first erase verify pass, the control logic can set wordlines of an erase block or subblock to a first erase voltage. On a second erase verify pass, the control logic can trigger a second erase verify pulse and set passing wordlines to an inhibit voltage, and failing wordlines to a second erase voltage higher than the first voltage. Inhibiting the already passing wordlines can reduce threshold voltage differences among the wordlines.

A semiconductor memory device includes a memory block with string units including a plurality of memory strings of memory cell transistors connected in series. Word lines are connected memory cell transistors in a same row and bit lines are respectively connected to one of the memory strings in each string unit. The bit lines are divided into different groups. A control circuit performs erasing on of the memory cell transistors in the memory block. The control circuit executes the erase verification on only a subset of memory strings in each string unit of the memory block rather than all memory strings.

In a memory controller configured to control a memory device including a plurality of memory blocks, the memory controller comprising: a memory interface configured to exchange data with the memory device; and a pre-program controller configured to perform a read operation on a last page of a program sequence for a plurality of pages in an erase target memory block when the memory device is in an idle state, and perform a pre-program operation on the erase target memory block according to the result obtained by performing the read operation, wherein the erase target memory block is a memory block on which an erase operation is to be performed among the plurality of memory blocks, and wherein the erase operation on the erase target memory block is performed after the pre-program operation is performed.

The storage device comprises a non-volatile memory coupled to a controller. The controller is configured to determine a first programming voltage by performing at least one program-verify iteration on a first word line using a voltage value which starts as a predetermined first initial voltage and is sequentially increased by a first voltage step amount following each failure to successfully program until the programming is completed. The controller is also configured to determine a second initial programming voltage by decreasing the first programming voltage by a second voltage step amount. The controller is further configured to perform at least one program-verify iteration on a second word line of the plurality of word lines using a voltage value which starts as the second initial programming voltage and is increased by the first voltage step amount following each sequential failure to successfully program until the programming is completed.

A digital neutron and photon track dosimeter based on three-dimensional Not-And (3D NAND) flash memory may be provided. A plurality of logical addresses respectively associated with a plurality of cells in a 3D NAND flash memory that have been flipped from a first charge state to a second charge state may be determined. Next, the plurality of logical addresses may be converted to a plurality of physical addresses associated with the plurality of cells in the 3D NAND flash memory that have been flipped from the first charge state to the second charge state by radiation. Then a radiation dose proportional to number and plurality of tracks within the plurality of cells associated with the plurality of physical address may be determined.

A nonvolatile memory device includes a memory cell array including first to fourth planes, a page buffer circuit that includes first to fourth page buffer units connected with the first to fourth planes, respectively, an input/output circuit that includes a first input/output unit connected with the first to fourth page buffer units and a second input/output unit connected with the second and fourth page buffer units, and control logic that controls the input/output circuit to output first data from one of the first to fourth page buffer units through the first input/output unit in a first read mode and output second data from one of the first and third page buffer units through the first input/output unit and third data from one of the second and fourth page buffer units through the second input/output unit in a second read mode.

Methods, systems and apparatus including computer-readable mediums for partially erasing blocks in a memory system to increase reliability are provided. In one aspect, a memory system includes a memory having a plurality of blocks and a memory controller coupled to the memory. The memory controller is configured to: execute a first erase operation on a particular block in the memory, the particular block including multiple sub-blocks each having respective memory cells, one or more memory cells in the particular block being in one or more programmed states before the first erase operation, then execute a second erase operation on a first sub-block of the particular block such that first respective memory cells of the first sub-block are in an erased state after the second erase operation. The memory controller can be configured to not execute the second erase operation on the one or more other sub-blocks of the particular block.

A memory device includes a plurality of memory blocks and each memory block includes a plurality of columns of memory cells. Each column of memory cells is coupled to a corresponding bit line. Upon completion of a power-up sequence, detect if a current leakage of corresponding columns in a group of memory blocks is greater than a predetermined level. If the current leakage of the corresponding columns in the group of memory blocks is greater than the predetermined level, perform an over-erasure correction on the corresponding columns.

According to the present embodiment, a nonvolatile semiconductor memory device includes a memory string group including k stacked memory strings, each of the memory strings including a plurality of nonvolatile memory cells connected in series, a selection transistor group including k selection transistors, each of the k selection transistors corresponding to each of the k memory strings respectively, the selection transistor group divided into n selection transistor sub-groups, each of the n selection transistor sub-groups including k/n selection transistors, n bit lines arranged in parallel to each of the k memory strings, and n bit line contacts arranged perpendicularly, each of the n bit line contacts connected to each of the n bit lines, respectively, each of the n bit line contacts connected to the k/n selection transistors belonging to the each of the n selection transistor sub-group respectively.