Abstract: Apparatuses and techniques are provided for programming memory cells while reducing widening of a threshold voltage distribution due to changes in the temperature between the time of programming and the time of a subsequent read operation. One technique is based on a correlation between program speed and temperature coefficient (Tco). A different verify test is used for different memory cells which have a common assigned data state according to the program loop number and the temperature. Another technique is based on sensing the memory cells to measure their subthreshold slope and classifying the memory cells into groups. The sensing can occur as a separate operation before programming or as part of the programming of user data. The subsequent programming of the memory cells involves adjusting the verify test of each memory cell based on its group and the temperature.

Abstract: A memory device is provided including physical block circuitry including a first lateral network arrangement and a second lateral network arrangement. Each of the first and second lateral network arrangements includes a single generator configured to output both a sense amplifier voltage VHSA and a data latch voltage VDDSA, in each of a first mode and a second mode. In the first mode, during which read and program verify and other operations may occur, the generator receives VHSA as a feedback signal and in the second mode, during which programming, POR, and EVFY operations may occur, the generator receives VDDSA as a feedback signal.

Abstract: Method for performing an erase program operation. Various methods include: erasing a block of cells by: applying a program pulse to a block of memory elements in the three-dimensional memory that programs the block of memory elements to a level below an erase verify level, where the three-dimensional memory comprises memory elements stacked vertically; performing a verify step to verify voltage levels of a group of memory elements; determining that a memory element of the group is outside of a threshold window defined between the erase verify level and a compact erase threshold amount; and applying a second program pulse to the memory element. Where erasing the block of memory elements creates an erased block, where a width of the voltage distribution of the erased memory elements in the erased block is the same as or below a width of a voltage distribution associated with programmed memory elements.

Abstract: Apparatuses and techniques are described for transferring data out of a memory device with low latency. Data can be stored in data transfer latches for NAND strings arranged in columns in divisions of a block. Data can be output from the data transfer latches for different columns in different divisions in each transfer. For example, the data output can include data from an nth column in some divisions and an n+1st column in other divisions. This avoids outputting unwanted data at the start of a data transfer. The data from the data transfer latches is output to a data pipeline and then to a set of control latch circuits. The data can be clocked out from a last control latch circuit of the set in a desired division order by use of separate multiplexer control signals for the control latch circuits.

Abstract: An apparatus is provided that includes a plurality of memory cells, a programming circuit configured to apply a plurality of programming pulses to the memory cells, and a scanning circuit configured to repeatedly switch between performing an n-state bitscan after each programming pulse until first predetermined criteria are satisfied, and performing an m-state bitscan after each programming pulse until second predetermined criteria are satisfied, where m>n, and n>0.

Abstract: A memory device is provided including physical block circuitry including a first lateral network arrangement and a second lateral network arrangement. Each of the first and second lateral network arrangements includes a single generator configured to output both a sense amplifier voltage VHSA and a data latch voltage VDDSA, in each of a first mode and a second mode. In the first mode, during which read and program verify and other operations may occur, the generator receives VHSA as a feedback signal and in the second mode, during which programming, POR, and EVFY operations may occur, the generator receives VDDSA as a feedback signal.

Abstract: Techniques are described for reprogramming memory cells to tighten threshold voltage distributions and improve data retention. In one aspect, the memory cells of a word line WLn are reprogrammed after programming of memory cells of an adjacent, later-programmed word line WLn+1. The reprogramming can be limited to lower state memory cells of WLn which are adjacent to lower state memory cells of WL+1. A program pulse magnitude used in the reprogramming can be tailored to the data states of the WLn memory cell and the adjacent, WLn+1 memory cell. In some cases, the program pulse magnitudes can be grouped to reduce the implementation complexity and time. The reprogramming can occur after an initial program operation has completed, during an idle time of a control circuit.

Abstract: Apparatuses and techniques are described for pre-charging NAND string channels in a pre-charge phase of a program operation. In one aspect, a hole-type pre-charge process is used at the source end of a NAND string, where a bottom of the NAND string is connected to a p-well of a substrate. By applying a positive voltage to the p-well and a lower voltage, such as 0 V or a negative voltage, to the source-side select gate transistors and the memory cells, the holes from the p-well are injected into the channel In another approach, the hole-type pre-charge process and an electron-type pre-charge process are used sequentially in separate time periods. In another approach, the hole-type pre-charge process is used at the source end of a NAND string while the electron-type pre-charge process is used at the drain end of the NAND string.

Abstract: Apparatuses, systems, and methods are disclosed for magnetoresistive random access memory. A magnetic tunnel junction (MTJ) for storing data may include a reference layer. A free layer of an MTJ may be separated from a reference layer by a barrier layer. A free layer may be configured such that one or more resistance states for an MTJ correspond to one or more positions of a magnetic domain wall within the free layer. A domain stabilization layer may be coupled to a portion of a free layer, and may be configured to prevent migration of a domain wall into the portion of the free layer.

Abstract: Techniques are provided for optimizing a program operation in a memory device to compensate for program speed variations due to block oxide thinning. In one approach, during a program operation, a program voltage which indicates program speed is acquired from sub-blocks with the highest and lowest program speeds. An initial program voltage for intermediate sub-blocks can be determined based on the acquired program voltages and the positions of the intermediate sub-blocks. The technique can accommodate a loss of one or both acquired program voltages if the programming is interrupted. In another approach, a program voltage which indicates program speed is acquired from one sub-block, and for a later-programmed sub-block, an appropriate offset is located from a table and summed with the acquired program voltage to determine an optimum initial program voltage.

Abstract: The switching device includes three terminals including an inner surface, an oxide layer on the inner surface of the third terminal, and a chalcogenide pillar extending through the oxide layer and the third terminal, the pillar being in electrical communication with the first terminal and the second terminal, wherein the voltage difference between the first terminal and the second terminal changes the channel from a first state to a second state when a threshold voltage between the first terminal and the second terminal is exceeded, the threshold voltage being dependent on temperature. The third terminal is resistive and receives a control signal to apply heat to the pillar and modulate the threshold voltage. The switching device can be used to select the memory stack through the bitline and provide a nearly limitless current based on the threshold switching conduction providing avalanche current conduction through the switching device.

Abstract: A memory system is provided that includes a first memory array including a first memory cell, a second memory array including a second memory cell, and a memory controller configured to determine a threshold voltage of the second memory cell to compensate a drift of a threshold voltage of the first memory cell and/or determine an offset voltage of the second memory cell to compensate an offset voltage of the first memory cell.

Abstract: Apparatuses and techniques are provided for programming memory cells while reducing widening of a threshold voltage distribution due to changes in the temperature between the time of programming and the time of a subsequent read operation. One technique is based on a correlation between program speed and temperature coefficient (Tco). A different verify test is used for different memory cells which have a common assigned data state according to the program loop number and the temperature. Another technique is based on sensing the memory cells to measure their subthreshold slope and classifying the memory cells into groups. The sensing can occur as a separate operation before programming or as part of the programming of user data. The subsequent programming of the memory cells involves adjusting the verify test of each memory cell based on its group and the temperature.

Abstract: An apparatus for erasing non-volatile storage elements in a non-volatile memory system is disclosed. The apparatus has consistent speed in gate induced drain leakage (GIDL) erase across the operating temperature of the memory system. In one aspect, a voltage source outputs an erase voltage to NAND strings. The NAND strings may draw a GIDL erase current in response to the erase voltage. The amount of GIDL erase current for a given erase voltage is highly temperature dependent. The GIDL erase current may be sampled, and the erase voltage regulated based on the GIDL erase current. Therefore, the GIDL erase current, as well as erase speed, may be kept uniform across operating temperatures.

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: A voltage regulator circuit is presented that can generate a stable and well-regulated output level to supply loads that have large dynamic current and capacitive variation. A compensation circuit is added to introduce a zero that tracks the voltage regulator's non-dominant pole. The compensation circuit includes a compensation transistor, whose gate is connected to receive the same voltage as the regulator's load driving pass transistor, and a series combination of a capacitance and a tracking resistance connected in series between the compensation transistor's gate and a supply level, where the value of the tracking resistance depends on the current supplied to the load. The tracking resistance can be implemented as a diode connected NMOS through which the compensation transistor is connected to the low supply level, or a diode connected PMOS whose current tracks that of the compensation transistor through a current mirror.

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: Techniques are provided to adaptively determine when to begin verify tests for memory cells during a program operation. The memory cells are programmed using a normal programming speed until their threshold voltage exceeds an initial verify voltage. The memory cells are then programmed further using a reduced programming speed until their threshold voltage exceeds a final verify voltage. In one aspect, a count of memory cells which exceeds the initial verify voltage is used to determine when to begin verify tests for a higher data state. In another aspect, a count of the higher state memory cells which exceeds the initial or final verify voltage is used to determine when to begin verify tests for the higher data state. The counted memory cells are not subject to the reduced programming speed.

Abstract: An apparatus includes a pair of memory cells configured to represent data using joint data states where one of the joint data states comprises an error-prone joint data state. The apparatus further includes an encoder configured to convert user data into joint data states according to a dual-cell gray-code encoding scheme in which the error-prone joint data state does not encode user data.

Abstract: An apparatus comprising strings of non-volatile memory cells, a first set of pathways connected to the strings, and a second set of pathways connected to the strings. The first set of pathways have first impedances that depend on location of respective strings. The second set of pathways having second impedances. The apparatus also includes one or more control circuits configured to compensate for location dependent impedance mismatch between the first set of pathways and the second set of pathways during memory operations on the non-volatile memory cells.