Abstract: A semiconductor memory device includes a memory cell array including first and second groups of memory strings respectively coupled to first and second groups of bit-lines, wherein the first and second groups of memory strings respectively include first and second groups of selection transistor cells; a peripheral circuit suitable for applying a program voltage, and performing program verification operation for the memory cell array; and a control logic suitable for controlling the peripheral circuit to perform a first program verification operation for the first group of selection transistor cells and a second program verification operation for the second group of selection transistor cells.

Abstract: Embodiments of erasing methods for a three-dimensional (3D) memory device are disclosed. The 3D memory device includes multiple decks vertically stacked over a substrate, wherein each deck includes a plurality of memory cells. The erasing method includes checking states of the plurality of memory cells of an erase-inhibit deck and preparing the erase-inhibit deck according to the states of the plurality of memory cells. The erasing method also includes applying an erase voltage at an array common source, applying a hold-release voltage on unselected word lines of the erase-inhibit deck, and applying a low voltage on selected word lines of a target deck.

Abstract: According to one embodiment, a semiconductor memory device includes: first and second memory cells; a first and second word lines; and a first bit line. The device is configured to execute first to sixth operations. In the first operation, a first voltage is applied to the first word line and a second voltage is applied to a semiconductor layer. In the second operation, the first voltage is applied to the second word line. In the third operation, a third voltage is applied to the first word line. In the fourth operation, the third voltage is applied to the second word line. In the fifth operation, a fourth voltage is applied to the first word line. In the sixth operation, the fourth voltage is applied to the second word line.

Abstract: Memory devices might include control circuitry that, when checking for a match of a stored digit of data and a received digit of data, might be configured to cause the memory device to apply a first voltage level to a control gate of a first memory cell of a memory cell pair, apply a second voltage level different than the first voltage level to a control gate of a second memory cell of that memory cell pair, determine whether that memory cell pair is deemed to be activated or deactivated in response to applying the first and second voltage levels, and deem a match between the stored digit of data and a received digit of data in response, in part, to whether that memory cell pair is deemed to be deactivated.

Abstract: A nonvolatile memory device according to an embodiment includes a substrate, a cell electrode structure disposed on the substrate and including interlayer insulating layers and gate electrode layers that are alternately stacked, a trench penetrating the cell structure on the substrate, a charge storage structure disposed on a sidewall surface of the trench, and a channel structure disposed adjacent to the charge storage structure and extending in a direction parallel to the sidewall surface. The channel structure includes a separate hole conduction layer and an adjacent and separate electron conduction layer. A control channel layer disposed on a control dielectric layer is a portion of the electron conduction layer configured to electrically connect to the channel structure, and to the charge storage structure. A control dielectric layer and a charge barrier layer are discrete but contiguous from the control channel structure to the charge storage structure.

Abstract: Apparatuses and methods for operating mixed mode blocks. One example method can include tracking single level cell (SLC) mode cycles and extra level cell (XLC) mode cycles performed on the mixed mode blocks, maintaining a mixed mode cycle count corresponding to the mixed mode blocks, and adjusting the mixed mode cycle count differently for mixed mode blocks operated in a SLC mode than for mixed blocks operated in a XLC mode.

Abstract: An operating method of a non-volatile memory device including a plurality of memory cells respectively connected to a plurality of word lines is provided. The operating method includes applying an erase detect voltage to a selected word line of the plurality of word lines to perform an erase detect operation on memory cells connected to the selected word line in response to a program command, applying a program voltage to the selected word line after the erase detect operation, and counting a number of undererased cells of the memory cells on which the erase detect operation has been performed.

Abstract: A semiconductor structure and an integrated circuit are provided. The semiconductor structure includes first well regions and a second well region in a semiconductor substrate; first transistors within the first wells; second transistors within the second well; and bit lines. The first wells are separately arranged along a first direction and a second direction. The second well continuously spreads between the first wells. Each first transistor and one of the second transistors are adjacent and connected to each other via a common source or common drain. The common drain or common source is electrically connected to a storage capacitor, and the electrically connected first and second transistors as well as the storage capacitor form a memory cell. The bit lines respectively extend between adjacent rows of the first wells. Adjacent memory cells arranged along the second direction are electrically connected to the same bit line.

Abstract: A method and system for controlling an MBC configured flash memory device to store data in an SBC storage mode, or a partial MBC storage mode. In a full MBC storage mode, pages of data are programmed sequentially from a first page to an Nth page for each physical row of memory cells. Up to N virtual page addresses per row of memory cells accompany each page to be programmed for designating the virtual position of the page in the row. For SBC or partial MBC data storage, a flash memory controller issues program command(s) to the MBC memory device using less than the maximum N virtual page addresses for each row. The MBC memory device sequentially executes programming operations up to the last received virtual page address for the row.

Abstract: Apparatuses and techniques are described for performing an operation which irreversibly prevents access to a set of memory cells. The operation provides a strong erase bias for select gate transistors of NAND strings. The erase bias induces a phenomenon in the select gate transistors which permanently increases their threshold voltages. This prevents access to the memory cells such as for program or read operations. The operation can involve one or more erase-verify iterations. In each erase-verify iteration, an erase bias is applied to the select gate transistors such as by charging up the channels of the NAND strings and holding a control gate voltage of the select gate transistors at a relatively low level, thereby causing a relatively high channel-to-control gate voltage.

Abstract: A method used in forming a memory array comprises forming a stack comprising vertically-alternating first tiers and second tiers. First insulator material is above the stack. The first insulator material comprises at least one of (a) and (b), where (a): silicon, nitrogen, and one or more of carbon, oxygen, boron, and phosphorus, and (b): silicon carbide. Channel-material strings are in and upwardly project from an uppermost material that is directly above the stack. Conducting material is directly against laterally-inner sides of individual of the upwardly-projecting channel-material strings and project upwardly from the individual upwardly-projecting channel-material strings. A ring comprising insulating material is formed individually circumferentially about the upwardly-projecting conducting material. Second insulator material is formed above the first insulator material, the ring, and the upwardly-projecting conducting material.

Abstract: An image signal output unit is controlled in accordance with a first control signal indicating either voltage state of an on voltage for causing a conductive state and an off voltage having a polarity different from that of the on voltage, and outputs an analog image signal corresponding to the electric charge held by an electric charge holding unit in the conductive state. A reset unit is controlled in accordance with a second control signal indicating either voltage state of the on voltage and the off voltage, resets the electric charge holding unit in the conductive state, transmits a fluctuation in the off voltage to the electric charge holding unit, and fluctuates the analog image signal. A reference signal generation unit generates a reference signal being a signal serving as a reference used when conversion from an analog image signal output from the image signal output unit into a digital image signal is performed.

Abstract: A non-volatile memory includes a memory cell region including a first metal pad, a peripheral circuit region including a second metal pad and vertically connected to the memory cell region by the first metal pad and the second metal pad, a memory cell array region in the memory cell region including an outer region proximate a first end of the memory cell region and an inner region separated from the first end by the outer region, first and second bit lines in the memory cell region, an outer memory cell string in the memory cell region including memory cells connected to an outer pillar extending vertically upward through the outer region, and an inner memory cell string including memory cells connected to an inner pillar extending vertically upward through the inner region, and a data input/output (I/O) circuit in the peripheral circuit region including a page buffer circuit that connects the first bit line during a first read operation directed to memory cells of the outer memory cell string, and connects

Abstract: A semiconductor memory device includes a memory block, a plurality of bit lines, a plurality of select gate lines, a plurality of word lines, and a controller. The memory block includes a plurality of memory strings, each memory string including a selection transistor and a plurality of memory cells. The plurality of bit lines are arranged in the first direction and connected to the respective memory strings. The plurality of select gate lines are arranged in the second direction and connected to gates of the respective selection transistors of the memory strings. The plurality of word lines are arranged in the third direction and connected to gates of the respective memory cells of the memory strings. The controller is configured to perform an erase operation in a unit of the memory block, and perform a sequence of erase verify operations.

Abstract: Systems and methods for managing non-volatile memory devices are provided. Embodiments discussed herein provide rapid restart protection for journaling system. The rapid restart protection prevents the NVM from experiencing memory saturation when the NVM system is being forced to handle multiple successive restarts.

Abstract: A methodology and structure for performing an erase verify in non-volatile memory is described. Both the odd wordlines and the even wordlines are driven to a high voltage level. This can be done simultaneously. The simultaneous charging of both the odd wordlines and the even wordlines, even when the erase verify will occur on only one of the odd or even wordlines reduces RC delay in the charging of the wordlines. After the odd and even wordlines are charged, then one set of wordlines, either the odd or even wordlines, is dropped to the erase verify voltage. The erase sense operation is then performed.

Abstract: The erase voltage controlled with higher accuracy than the related art when erasing data in a non-volatile semiconductor memory device is provided. An control circuit for controlling an erase voltage includes: a slope adjustment circuit that controls a slope having a step shape by controlling a step voltage, a target voltage, and a step width of the erase voltage. The slope adjustment circuit repeatedly increases the erase voltage by the step voltage for each predetermined clock pulse control signal to the target voltage based on the step voltage and the target voltage, and outputs the clock pulse control signal to the erase voltage generation circuit by repeatedly clocking each time interval corresponding to the step width based on the step width.

Abstract: Devices, methods, and systems for managing temperature dependent failures in a memory device. An erase failure of a memory block is detected, and marked as a grown bad block if the memory device temperature is below a threshold temperature. If the temperature exceeds the threshold temperature, it is determined whether memory cells of the block exceed a first threshold voltage. If the memory cells of the block exceed the first threshold voltage, the block is marked as a potential grown bad block. If the memory cells of the block are below the first threshold voltage, it is determined whether a number of the memory cells of the block exceed a second threshold voltage. If the memory cells of the block are below the second threshold, the block is programmed. If the memory cells of the block exceed the second threshold, the block is marked for error correction and programmed.

Abstract: Gate-induced leakage current that is independent of a location of a physical p-n junction between a semiconductor channel and a source/drain region can be provided within a NAND string of a three-dimensional memory device by employing at least one leakage current control circuit that is activated during an erase operation. During the erase operation, an accumulation region and an inversion region can be formed between a vertically-neighboring pair of electrically conductive layers with a depletion region therebetween. The depletion region can generate and inject majority charge carriers into the semiconductor channel during the erase operation. The depletion region can be formed in the source region or in the drain region and may not overlap with a physical p-n junction. Thus, the charge injection location can be independent of the location of the physical p-n junction.

Abstract: A semiconductor memory device according to an embodiment, includes a plurality of semiconductor pillars extending in a first direction and being arranged along a second direction crossing the first direction, two interconnects extending in the second direction and being provided on two sides of the plurality of semiconductor pillars in a third direction crossing the first direction and the second direction, and an electrode film disposed between each of the semiconductor pillars and each of the interconnects. The two interconnects are drivable independently from each other.

Abstract: A semiconductor storage device includes a first memory cell and a second memory cell which are connected to each other in series, a first word line which is connected to the first memory cell, a second word line which is connected to the second memory cell, and a control circuit. The control circuit is configured to charge a first node while applying a second voltage to the second word line and a first voltage to the first word line, to charge a second node on the basis of a voltage of the charged first node, to discharge the second node while applying the second voltage to the second word line and a third voltage to the first word line, and to read data from the first memory cell on the basis of voltages of the charged and discharged second node.

Abstract: A memory includes a rewritable non-volatile memory cell and input circuitry coupled to the memory cell. The input circuitry, in operation, erases the memory cell in response to reception of a request to read the memory cell. Similarly, a read-once memory includes an addressable, non-volatile memory having a plurality of rewriteable memory cells. Input circuitry coupled to the non-volatile memory responds to reception of a request to read content stored at an address in the non-volatile memory by erasing the content stored at the address of the non-volatile memory.

Abstract: Provided is an erase method for a multi-tier three-dimension (3D) memory including a plurality of tiers and a plurality of blocks, each of the tiers including a plurality of word lines. The erase method includes: in erasing a selected block among the plurality of blocks, in a current iteration, selecting at least one tier among the plurality of tiers to be erased by a first erase voltage; determining whether the at least one tier passes erase verification; and if the at least one tier passes erase verification, in a next iteration, inhibiting the at least tier which already passes erase verification from erase.

Abstract: A memory controller is disclosed. The memory controller is configured to control the execution of a suspend operation by a memory device. The memory controller includes: a processor configured to output an operation control signal when the memory device is performing a program/erase operation; and a suspend operation manager configured to output suspend mode change information based on the operation control signal and suspend information, wherein the processor is further configured to control the memory controller such that the memory controller outputs a suspend mode change command and a suspend command based on the suspend mode change information.

Abstract: A tracking voltage generator, the latter including: a first transistor having a first leakage current and which is coupled with the flipped gate transistor so that a difference between a gate-source voltage (Vgs) of a flipped gate transistor and the first transistor is approximately equal to a bandgap voltage of a semiconductor material from which the tracking voltage generator is formed; an output node providing a tracking voltage which has a positive or negative temperature dependency based on the flipped gate transistor and the first transistor; and a second transistor connected to the output node and which has a second leakage current. A current reference includes: the tracking voltage generator; an amplifier to receive the tracking voltage and output an amplified signal; a control transistor to receive the amplified signal and conduct a reference current therethrough; and a control resistor connected in series with the control transistor.

Abstract: There are provided a semiconductor memory and an operating method thereof. The semiconductor memory includes: a memory block including a plurality of pages; a peripheral circuit for performing a first erase operation, a program operation, and a second erase operation on the memory block in a write operation on the memory block; and control logic for controlling the peripheral circuit to perform the write operation. The control logic is configured to control the peripheral circuit to erase a plurality of memory cells included in the memory block to a pre-erase state having a threshold voltage higher than a threshold voltage of a target erase state in the first erase operation, and controls the peripheral circuit to erase some memory cells among the plurality of memory cells to the target erase state in the second erase operation.

Abstract: Word-line drivers, memories, and methods of operating word-line drivers are provided. A word-line driver coupled to an array of memory cells includes a decoder powered by a first power supply. The decoder is configured to decode an address to provide a plurality of word-line signals. The word-line driver also includes a plurality of output stages powered by a second power supply that is different than the first power supply. Each of the output stages includes a first transistor having a gate controlled by a first control signal and an inverter. The inverter is coupled between the first transistor and a ground and has an input coupled to the decoder to receive one of the word-line signals. The word-line driver also includes pull-down circuitry coupled between the gates of the first transistors and the ground and activated by a second control signal.

Abstract: The present invention relates to a flash memory cell with only four terminals and a high voltage row decoder for operating an array of such flash memory cells. The invention allows for fewer terminals for each flash memory cell compared to the prior art, which results in a simplification of the decoder circuitry and overall die space required per flash memory cells. The invention also provides for the use of high voltages on one or more of the four terminals to allow for read, erase, and programming operations despite the lower number of terminals compared to prior art flash memory cells.

Abstract: A memory system includes a memory device including a plurality of blocks, each capable of storing data, and a controller, coupled with the memory device. The controller can perform at least one sub erase operation on each of the plurality of blocks, and variably increase an erase count of each of the plurality of blocks based on a timing of erasing data of each of the plurality of blocks through the sub erase operation.

Abstract: Methods and design system for generating 2-dimensional distribution architecture for testing integrated circuit design that utilizes double grid to minimize interdependencies between grid cells and the associated functional logic to facilitate the a physically efficient scan of integrated circuit designs, that simultaneously minimizes required test application time (“TAT”), test data volume, tester memory and cost associated with design for test (“DFT”), while also retaining test coverage. An additional grid parallel to a 2-dimensional XOR grid may be implemented that improves the quality of test coverage by optimally adding additional data inputs which decreases correlations between grid cells. A column spreader may feed data into column wires and row spreader may feed data into column wires. The double grid allows data to be fed into two wires, row and column, respectively, which provides twice as much stimulus data in each direction, without significantly increasing the wiring used to build the grid.

Abstract: Techniques for profiling storage blocks in non-transitory memory (e.g., flash memory dies) to determine their retention capability, and assigning them with labels based on retention, are described. A superblock (SB) can be formed from physical blocks with the same labels located in different dies. The disclosed system and methods improve storage efficiency when the update frequency of stored data is non-uniform, as is typically the case. Moreover, the disclosed embodiments improve the reliability of solid state drives (SSDs), as well as reduce data refresh frequency and write amplification due to periodic refresh. A storage system can comprise a controller configured to obtain expected retention times for a plurality of storage blocks. The controller can partition the blocks into superblocks based on the retention times. A respective superblock is associated with a superblock retention time range, and contains blocks having expected retention times within the retention time range.

Abstract: Certain aspects of the present disclosure provide apparatus and techniques for communicating error information during memory operations. For example, certain aspects of the present disclosure may provide a method for memory operations. The method generally including receiving a command from a host device, performing memory operations corresponding to the command received from the host device, detecting an error during the memory operations, and communicating the error based on the detection, wherein the error is communicated before receiving another command from the host device.

Abstract: A semiconductor storage apparatus of high convenience, which improves utilization efficiency of a memory region, is provided. A flash memory provided in the disclosure includes a memory controller and an NAND memory device. The memory controller includes an SRAM, an RRAM, and a write/selector. The SRAM stores a conversion table that converts a logical address into a physical address. The RRAM temporarily stores a small amount of data which should be programmed. The write/selector selectively writes the to-be-programmed data into the RRAM or an NAND memory unit of the NAND memory device.

Abstract: Techniques are provided for optimizing an erase operation in a memory device to compensate for erase speed variations due to blocking oxide thinning In an erase operation for a block, the channels of NAND strings in different sub-blocks can be charged up by different amounts. One approach adjusts the control gate voltage of a first select gate transistor in a NAND string. This adjusts the amount of holes generated in the channel due to gate-induced drain leakage. Another approach adjusts the control gate voltage of additional select gate transistors in the NAND string to adjust the conductivity of the adjacent channel regions. Another approach applies different bit line voltages to different rows of NAND strings in each sub-block.

Abstract: An operating method of a nonvolatile memory device which includes a cell string including a plurality of cell transistors connected in series between a bit line and a common source line and stacked in a direction perpendicular to a substrate, the method including: programming an erase control transistor of the plurality of cell transistors; and after the erase control transistor is programmed, applying an erase voltage to the common source line or the bit line and applying an erase control voltage to an erase control line connected to the erase control transistor, wherein the erase control voltage is less than the erase voltage and greater than a ground voltage, and wherein the erase control transistor is between a ground selection transistor of the plurality of cell transistors and the common source line or between a string selection transistor of the plurality of cell transistors and the bit line.

Abstract: A semiconductor memory device includes a memory cell array including a plurality of memory blocks, a voltage generator suitable for applying an erase voltage to a source line of at least one memory block selected from among the plurality of memory blocks during an erase operation, a read and write circuit suitable for applying an initial setting voltage to bit lines of at least one memory block during the erase operation, and a control logic suitable for controlling the voltage generator and the read and write circuit to apply the initial setting voltage to the bit lines before applying the erase voltage to the source line.

Abstract: An apparatus comprising strings of non-volatile memory cells is disclosed. Each string comprises non-volatile memory cells, an operative select gate, and a dummy select gate. The apparatus comprises a select line connected to the operative select gate of each string, and a dummy line connected to the dummy select gate of each string. The dummy line is an immediate neighbor to the select line. The apparatus comprises a control circuit configured to apply a voltage waveform to the select line while the dummy line is floating. The control circuit is configured to detect a floating voltage on the dummy line while applying the voltage waveform to the select line. The control circuit is configured to determine a condition of the voltage waveform at a target location on the select line based on the floating voltage on the dummy line.

Abstract: Circuit designs and operating techniques for a storage device that includes, in one implementation, a memory controller configured to control a memory device including a plurality of memory blocks, each including a plurality of memory cells. The memory controller may include a memory device interface configured to perform data communication with the memory device, and a soft program controller communicatively coupled to the memory device interface and configured to count a number of iterations that an erase operation on an erase target memory block, among the plurality of memory blocks, has been suspended until the erase operation is completed, and to perform a soft program operation on the erase target memory block after the erase operation has been completed, based on the number of iterations that the erase operation on the erase target memory block has been suspended.

Abstract: The present invention provides a semiconductor memory device capable of performing rapid erasing while reducing power consumption. In the flash memory of the present invention, the voltage of the P well is detected by the voltage detecting unit 200 during the erasing operation. When the voltage is lower than the threshold value, it is determined that the off leakage current of the selection transistor of the non-selection block is large, and the voltage of the global word line at the time of applying the next erase pulse is increased. When the voltage is above the threshold value, it is determined that the off leakage current is small, and the voltage of the global word line at the time of applying the next erase pulse is maintained.

Abstract: A semiconductor device includes a substrate including a doped region of a first doping concentration that extends downward from an upper surface of the substrate; a first stack on the upper surface, including first insulating layers and first conductive layers alternatively stacked, a first channel layer, a first memory layer and a first conductive connector configured to receive a first voltage, the first conductive connector on the first channel layer, having a second doping concentration; a second stack on the first stack including second insulating layers and second conductive layers alternatively stacked, a second channel layer, a second memory layer, the second conductive layer configured to receive the second voltage; a second conductive connector on the second channel layer, configured to receive an erasing voltage, the first conductive connector electrically connected to the first and second channel layers; the first doping concentration smaller than the second doping concentration.

Abstract: A vehicle control system includes: a first device that generates trajectory data indicating a future trajectory of a host vehicle and outputs the generated trajectory data; a second device that controls at least one of acceleration/deceleration and steering of the host vehicle on the basis of the trajectory data generated by the first device; and a third device that receives the trajectory data generated by the first device and writes the received trajectory data in a storage unit thereof, the third device being a device separate from at least the first device, wherein when an abnormality occurs in the trajectory data output by the first device, the second device controls at least one of acceleration/deceleration and steering of the host vehicle on the basis of the trajectory data which has been received by the third device and written in the storage unit before the abnormality occurred.

Abstract: A methodology and structure for performing an erase verify in non-volatile memory is described. Both the odd wordlines and the even wordlines are driven to a high voltage level. This can be done simultaneously. The simultaneous charging of both the odd wordlines and the even wordlines, even when the erase verify will occur on only one of the odd or even wordlines reduces RC delay in the charging of the wordlines. After the odd and even wordlines are charged, then one set of wordlines, either the odd or even wordlines, is dropped to the erase verify voltage. The erase sense operation is then performed.

Abstract: According to one embodiment, a semiconductor memory device includes: a first memory cell; a second memory cell; a first word line; a second word line; and a first bit line. The first memory cell faces the second memory cell. When reading data from the first memory cell, the semiconductor memory device is configured to perform the first operation in which a first voltage is applied to the first word line and a second voltage higher than the first voltage is applied to the second word line, and perform the second operation in which a third voltage higher than the first voltage and a fourth voltage different from the third voltage are applied to the first word line and a fifth voltage lower than the second to the fourth voltage is applied to the second word line.

Abstract: A semiconductor device includes a memory string coupled between a common source line and a bit line, the memory string including at least one first selection transistor, a plurality of memory cells, and a plurality of second selection transistors. The semiconductor device also includes selection lines respectively coupled to the second selection transistors. The semiconductor device further includes a control logic circuit configured to float a first group of selection lines from among the selection lines at a first time and configured to float a second group of selection lines from among the selection lines at a second time different from the first time.

Abstract: A dynamic power control system includes an external power input terminal receiving a first output electric current from a power management circuit outside of the memory device; a variable charge pump receiving a second input voltage and a second input electric current, boosting the second input voltage to a second output voltage, and outputting the second output voltage and a second output electric current to the memory device; and a feedback controller to compare a ratio of the first output electric current to the first input electric current and a ratio of the second output electric current to the second input electric current, and to select one of the power management circuit and the variable charge pump to supply power to the memory device, according to the comparison result.

Abstract: An integrated circuit device includes channel structures extending from a substrate in a vertical direction, memory cell strings disposed along the plurality of channel structures, gate lines spaced apart from one another in the vertical direction and including erase control lines and string selection lines, and driving transistors including erase control driving transistors connected to the erase control lines and string selection driving transistors connected to the string selection lines.

Abstract: In some examples, a defective memory cell detection circuitry is configured to provide a failure signal indicative of a failure of a sub-group of memory cells (e.g., a row of memory cells). The failure signal is generated responsive to the failure of a sense line to transition to one of a set of reference voltages within a threshold time from a memory command. In some examples, failure signals indicative of a failure of a sub-group of memory cells is used by vehicle computer control systems to operate a vehicle.

Abstract: In a method of erasing data in a nonvolatile memory device including a memory block, it is determined whether a data erase characteristic for the memory block is degraded for each predetermined cycle. The memory block has a plurality of memory cells therein, the plurality of memory cells being stacked in a vertical direction relative to an underlying substrate. A data erase operation is performed by changing a level of a voltage applied to selection transistors for selecting the memory block as an erase target block when it is determined that the data erase characteristic is degraded.

Abstract: A semiconductor memory device includes a memory block, a plurality of bit lines, a plurality of select gate lines, a plurality of word lines, and a controller. The memory block includes a plurality of memory strings, each memory string including a selection transistor and a plurality of memory cells. The plurality of bit lines are arranged in the first direction and connected to the respective memory strings. The plurality of select gate lines are arranged in the second direction and connected to gates of the respective selection transistors of the memory strings. The plurality of word lines are arranged in the third direction and connected to gates of the respective memory cells of the memory strings. The controller is configured to perform an erase operation in a unit of the memory block, and perform a sequence of erase verify operations.

Abstract: An EEPROM and methods for erasing, programming and reading it, the EEPROM includes a plurality of split-gate storage arrays, each of the plurality of split-gate storage cells including a source connected with a first bit line, a drain connected with a second bit line, a first control gate connected with a first store position, a word line gate connected with a word line and a second control gate connected with a second store position; and the first control gate is connected with a first control gate line, and the second control gate is connected with a second control gate line, wherein every N columns of the split-gate storage cells are formed on a first well structure, adjacent first well structures are separated by a second well structures having a different doping type with that of the first well structures, and N is a positive integer.