Patent classifications
G11C16/04
Calculating soft metrics depending on threshold voltages of memory cells in multiple neighbor word lines
A memory controller includes an interface and a processor. The interface communicates with memory cells organized in multiple Word Lines (WLs). The processor is configured to read a Code Word (CW) of an Error Correction Code (ECC) from a group of multiple memory cells belonging to a target WL, to calculate for a given memory cell (i) a first soft metric, depending on a first threshold voltage of a first neighbor memory cell in a first WL neighboring the target WL, and (ii) a second soft metric, depending on a second threshold voltage of a second neighbor memory cell in a second WL neighboring the target WL, to calculate a combined soft metric based on both the first and second soft metrics and assign the combined soft metric to the given memory cell, and to decode the CW based on the combined soft metric, to produce a decoded CW.
MEMORY DEVICE AND METHOD OF OPERATING THE SAME
A memory device includes a memory block including memory cells to which a program voltage is applied through a word line. The memory device also includes a peripheral circuit configured to perform a verify operation of comparing threshold voltages of the memory cells with a verify voltage on each of a plurality of program levels. The memory device further includes a control logic circuit configured to control the peripheral circuit to apply a plurality of blind voltages related to a target level among the plurality of program levels to the word line, and determine a start time point of a verify operation corresponding to a next program level of the target level using the number of fail bits for each of the plurality of blind voltages.
MEMORY WITH A SOURCE PLATE DISCHARGE CIRCUIT
Memory systems and devices with source plate discharge circuits (and associated methods) are described herein. In one embodiment, a memory device includes (a) a plurality of memory cells, (b) a source plate electrically coupled to the plurality of memory cells, and (c) a discharge circuit. The discharge circuit can include a bipolar junction transistor device electrically coupled to the source plate and configured to drop a voltage at the source plate by, for example, discharging current through the bipolar junction transistor device. In some embodiments, the bipolar junction transistor device can be activated using a low-voltage switch or a high-voltage switch electrically coupled to the bipolar junction transistor. In these and other embodiments, the bipolar junction transistor device can operate in an avalanche mode while discharging current to drop the voltage at the source plate.
NON-VOLATILE MEMORY WITH SUB-BLOCK BASED SELF-BOOSTING SCHEME
To help reduce program disturbs in non-selected NAND strings of a non-volatile memory, a sub-block based boosting scheme in introduced. For a three dimensional NAND memory structure, in which the memory cells above a joint region form an upper sub-block and memory cells below the joint region form a lower sub-block, dummy word lines in the joint region act as select gates to allow boosting at the sub-block level when the lower block is being programmed in a reverse order.
INTERLEAVED STRING DRIVERS, STRING DRIVER WITH NARROW ACTIVE REGION, AND GATED LDD STRING DRIVER
A memory device includes a first string driver circuit and a second string driver circuit that are disposed laterally adjacent to each other in a length direction of a memory subsystem. The first and the second string driver circuits are disposed in an interleaved layout configuration such that the first connections of the first string driver are offset from the second connections of the second string driver in a width direction. For a same effective distance between the corresponding opposing first and second connections, a first pitch length corresponding to the interleaved layout configuration of the first and second string drivers is less by a predetermined reduction amount than a second pitch length between the first and second string drivers when disposed in a non-interleaved layout configuration in which each of the first connections is in-line with the corresponding second connection.
Memory device and method of operation
Discussed herein are systems and methods for charging an access line to a non-volatile memory cell during a standby state, such as to prevent or mitigate standby-state charge loss. An embodiment of a memory device comprises a memory cell, a string driver circuit, and a charging circuit. The string driver circuit is coupled to the memory cell via a local word line, and has a common p-well. The charging circuit, in response to a voltage of a global word line of the memory device falling below a reference voltage during a standby state, couple a supply voltage to the common p-well of the string driver circuit to charge the global word line to a positive bias potential. The memory device includes a leakage compensation circuit to compensate for the junction leakage.
Memory devices having cell over periphery structure, memory packages including the same, and methods of manufacturing the same
A memory device includes first and second semiconductor layers. The first semiconductor layer includes wordlines and bitlines, an upper substrate, and a memory cell array. The memory cell array includes a memory blocks. The second semiconductor layer includes a lower substrate, and an address decoder. Each memory block includes a core region including a memory cells, a first extension region adjacent to a first side of the core region and including a plurality of wordline contacts, and a second extension region adjacent to a second side of the core region and including an insulating mold structure. The second extension region includes step zones and at least one flat zone. Through-hole vias penetrating the insulating mold structure are in the flat zone. The wordlines and the address decoder are electrically connected with each other by at least the through-hole vias.
Erasing method for 3D NAND flash memory
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.
Storage device and reading method
According to one embodiment, a storage device includes a nonvolatile memory and a controller. The controller is configured to read data from the nonvolatile memory by applying a read voltage to the nonvolatile memory. The controller is configured to correct the read voltage based on a difference between a measured value of a bit number obtained when the data is read from the nonvolatile memory by applying the read voltage to the nonvolatile memory and an expected value of the bit number.
Page buffer circuit with bit line select transistor
Aspects of the disclosure provide a memory device. For example, the memory device can include a memory array, a bitline and a buffer. The memory array can include a plurality of memory strings. The memory strings can be divided into a first memory string group and a second memory string group. The bitline can include a first bitline segment coupled to the first memory string group and a second bitline segment coupled to the second memory string group. The first bitline segment can be disposed between the first memory string group and the buffer and be connected to the buffer through a first conduction path. The second bitline segment can be disposed between the second memory string group and the buffer and be connected to the buffer through a second conduction path.