A location of at least one fail bit to be repaired in a memory block of a memory is extracted from at least one memory test on the memory block. An available repair resource in the memory for repairing the memory block is obtained. It is checked, using machine learning, whether the at least one fail bit is unrepairable, according to the location of the at least one fail bit, and the available repair resource. When the checking indicates that the at least one fail bit is not unrepairable, it is determined whether a Constraint Satisfaction Problem (CSP) containing a plurality of constraints is solvable. The constraints correspond to the location of the at least one fail bit in the memory block, and the available repair resource. In response to determining that the CSP is not solvable, the memory block is marked as unrepairable or the memory is rejected.

In a method of testing a nonvolatile memory device including a first semiconductor layer in which and a second semiconductor layer is formed prior to the first semiconductor layer, circuit elements including a page buffer circuit are provided in the second semiconductor layer, an on state of nonvolatile memory cells which are not connected to the page buffer circuit is mimicked by providing a conducting path between an internal node of a bit-line connection circuit connected between a sensing node and a bit-line node of the page buffer circuit and a voltage terminal to receive a first voltage, a sensing and latching operation with the on state being mimicked is performed in the page buffer circuit and a determination is made as to whether the page buffer circuit operates normally is made based on a result of the sensing and latching operation.

A nonvolatile memory device includes memory cell region including a first metal pad and a peripheral circuit region including a second metal pad, is connected to the memory cell region by the first metal pad and the second metal pad and includes including an address decoder and a page buffer circuit located on a first substrate. A memory cell array is provided in the memory cell region, which includes a first vertical structure on a second substrate. The first vertical structure includes first sub-blocks and first via areas in which one or more through-hole vias are provided, and through-hole vias pass through the first vertical structure. A control circuit in the peripheral circuit region groups the memory blocks into a plurality of groups based on whether the memory blocks is close to the first via areas and performs address re-mapping.

A memory controller includes, in one embodiment, a memory interface, a plurality of decoders, and a controller circuit. The memory interface is configured to interface with a memory having a plurality of wordlines. Each decoder of the plurality of decoders is configured to determine a bit error rate (BER). The controller circuit configured to generate a plurality of bit-error-rate estimation scan (BES) hypotheses for one wordline of the plurality of wordlines, divide the plurality of BES hypotheses among the plurality of decoders, receive BER results from the plurality of decoders based on the plurality of BES hypotheses, and adjust one or more read locations of the one wordline based on the BER results from the plurality of decoders.

3D memory arrays including dummy conductive lines and methods of forming the same are disclosed. In an embodiment, a memory array includes a ferroelectric (FE) material over a semiconductor substrate, the FE material including vertical sidewalls in contact with a word line; an oxide semiconductor (OS) layer over the FE material, the OS layer contacting a source line and a bit line, the FE material being between the OS layer and the word line; a transistor including a portion of the FE material, a portion of the word line, a portion of the OS layer, a portion of the source line, and a portion of the bit line; and a first dummy word line between the transistor and the semiconductor substrate, the FE material further including first tapered sidewalls in contact with the first dummy word line.

A memory device includes a content addressable memory (CAM) block storing a plurality of stored search keys. The memory device further includes control logic that determines a first number of memory cells in at least one string of the CAM block storing one of the plurality of stored search keys, the first number of memory cells storing a first logical value, and stores a calculated parity value representing the first number of memory cells in a page cache associated with the CAM block. The control logic further reads stored parity data from one or more memory cells in the at least one string, the one or more memory cells connected to one or more additional wordlines in the CAM block, and compares the calculated parity value to the stored parity data to determine whether an error is present in the one of the plurality of stored search keys in the CAM block.

A method for detecting and isolating defective memory plane(s) of a non-volatile memory structure during a program verify operation, comprising: initiating, for each plane, a word line verify voltage level scan with a bit scan pass fail criterion and at a starting voltage located within an intended program threshold voltage distribution curve, incrementally decreasing the word line verify voltage by a predetermined offset until a specific condition of the scan is obtained, and storing the voltage at which the specific condition of the scan is obtained, wherein the stored voltage represents a voltage of an upper tail portion of an actual programmed threshold voltage distribution curve of the plane. The stored voltages of all of the memory planes of the structure are compared to determine which plane corresponds to the lowest stored voltage. A “fail” status is applied to the plane corresponding to the lowest stored voltage.

A memory controller includes, in one embodiment, a memory interface and a controller circuit. The memory interface is configured to interface with a memory interface configured to interface with a memory having a plurality of memory blocks. Each memory block has a plurality of strings. The controller circuit is configured to perform a string defect leakage check on one of the memory blocks during a first programming operation of the one memory block, determine whether the one memory block has one or more string to string shorts based on the string defect leakage check, and resolve the string to string shorts in response to determining that the one of the memory blocks has the string to string shorts.

A nonvolatile memory device includes a memory cell array having cell strings that each includes memory cells stacked on a substrate in a direction perpendicular to the substrate. A row decoder is connected with the memory cells through word lines. The row decoder applies a setting voltage to at least one word line of the word lines and floats the at least one word line during a floating time. A page buffer circuit is connected with the cell strings through bit lines. The page buffer senses voltage changes of the bit lines after the at least one word line is floated during the floating time and outputs a page buffer signal as a sensing result. A counter counts a number of off-cells in response to the page buffer signal. A detecting circuit outputs a detection signal associated with a defect cell based on the number of off-cells.

A memory apparatus and method of operation are provided. The apparatus includes memory cells connected to one of a plurality of word lines and arranged in strings and configured to retain a threshold voltage corresponding to one of a plurality of memory states. A control circuit is coupled to the plurality of word lines and strings and is configured to erase the memory cells using a stripe erase operation in response to determining a cycle count is less than a predetermined cycle count maximum threshold. The control circuit is also configured to perform a dummy cycle operation in response to determining the cycle count is not less than the predetermined cycle count maximum threshold.