Sandisk Patent Grants

Three-dimensional memory device with a columnar memory opening arrangement and method of making thereof

Granted: December 19, 2023
Patent Number: 11849578
A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, a plurality of periodic two-dimensional arrays of memory openings vertically extending through the alternating stack, a plurality of periodic two-dimensional arrays of memory opening fill structures, and bit lines. The bit lines laterally extend along a second horizontal direction. Each periodic two-dimensional array of memory openings includes…

Three-dimensional memory device with backside support pillar structures and methods of forming the same

Granted: December 12, 2023
Patent Number: 11844222
At least one vertically alternating sequence of continuous insulating layers and continuous sacrificial material layers is formed over a substrate. Rows of backside support pillar structures are formed through the at least one vertically alternating sequence. Memory stack structures are formed through the at least one vertically alternating sequence. A two-dimensional array of discrete backside trenches is formed through the at least one vertically alternating sequence. Contiguous…

Systems and methods for dynamically sensing a memory block

Granted: December 12, 2023
Patent Number: 11842775
A memory device that dynamically adjusts the sense time to read an open block of a memory block is disclosed. The adjusted sense time is based upon various considerations, including the sense time of the closed block equivalent and the openness of the open block. This allows the memory device to maintain a fixed Vt as well as reduce failed bit count, i.e., read errors due to an insufficient sense time. Also, the dynamic adjustment of sense time can optimize system performance and…

Transistors with stepped contact via structures and methods of forming the same

Granted: December 5, 2023
Patent Number: 11837640
A transistor includes a semiconductor substrate including a first active region, a second active region, and a semiconductor channel, a gate stack structure that overlies the semiconductor channel, a proximal dielectric material layer overlying the semiconductor substrate, laterally surrounding the gate stack structure, a distal dielectric material layer overlying the proximal dielectric material layer, and a first contact via structure contacting the first active region having a greater…

Transistor circuits including fringeless transistors and method of making the same

Granted: December 5, 2023
Patent Number: 11837601
A field effect transistor includes a gate dielectric and a gate electrode overlying an active region and contacting a sidewall of a trench isolation structure. The transistor may be a fringeless transistor in which the gate electrode does not overlie a portion of the trench isolation region. A planar dielectric spacer plate and a conductive gate cap structure may overlie the gate electrode. The conductive gate cap structure may have a z-shaped vertical cross-sectional profile to contact…

Smart erase verify in non-volatile memory structures

Granted: December 5, 2023
Patent Number: 11837297
A method for dynamically adjusting an erase voltage level to be applied in a subsequent erase cycle, comprising: in a current erase cycle, initiating a current erase/verify loop by applying an initial stored erase voltage level according to an erase sequence in which each successive erase/verify loop is incremented by a pre-determined voltage amount, storing an erase/verify loop count, and determining whether the current erase cycle is complete according to a pass criterion. If the erase…

Non-volatile memory with adjusted bit line voltage during verify

Granted: December 5, 2023
Patent Number: 11837296
A control circuit connected to non-volatile memory cells applies a programming signal to a plurality of the non-volatile memory cells in order to program the plurality of the non-volatile memory cells to a set of data states. The control circuit performs program verification for the non-volatile memory cells, including applying bit line voltages during program verification based on word line position and data state being verified.

Detecting bit line open circuits and short circuits in memory device with memory die bonded to control die

Granted: November 28, 2023
Patent Number: 11830564
Apparatuses and techniques are presented for detecting bit line open circuits and short circuits in a memory device in which a memory die is inverted and bonded to a control die. In one approach, the control die comprises a set of bit lines which are connected to a set of bit lines of the memory die, and the set of bit lines of the control die comprise ground transistors, e.g., transistors connected to a ground node. Ground transistors of even-numbered bit lines may be commonly…

Semi receiver side write training for non-volatile memory system

Granted: November 28, 2023
Patent Number: 11829281
Technology is disclosed herein for semi receiver side write training in a non-volatile memory system. The transmitting device has delay taps that control the delay between a data strobe signal and data signals sent on the communication bus. The delay taps on the transmitting device are more precise that can typically be fabricated on the receiving device (e.g., NAND memory die). However, the receiving device performs the comparisons between test data and expected data, which alleviates…

Programming techniques for memory devices having partial drain-side select gates

Granted: November 21, 2023
Patent Number: 11823744
A method of operating a memory device. The method includes the step of preparing a memory device that includes a first group of the memory holes with full SGD transistors and a second group of the memory holes with partial SGD transistors. The second group includes both a set of selected partial SGD transistors and a set of unselected partial SGD transistors. The method proceeds with electrically floating a first unselected partial SGD transistor of the set of unselected partial SGD…

Systems and methods for detecting erratic programming in a memory system

Granted: November 14, 2023
Patent Number: 11817157
The storage device that includes a non-volatile memory with a control circuitry that is communicatively coupled to an array of memory cells that are arranged in a plurality of word lines. The control circuitry is configured to program the memory cells in a plurality of programming loops. The programming loops include applying a programming pulse to a selected word line of the plurality of word lines. The programming loops also include applying a verify pulse VN to the selected word line…

Non-volatile memory with different word line hook up regions based on pass through signals

Granted: November 14, 2023
Patent Number: 11817150
To overcome a shortage of area for horizontal metal lines to connect word line switch transistors to corresponding word lines and for pass through signal lines, it is proposed to implement multiple architectures for the word line hook up regions. For example, some areas of a die will be designed to provide extra horizontal metal lines to connect word line switch transistors to word lines and other areas of the die will be designed to provide extra pass through signal lines.

Memory device including laterally perforated support pillar structures surrounding contact via structures and methods for forming the same

Granted: November 7, 2023
Patent Number: 11812598
A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers, memory stack structures vertically extending through the alternating stack, a retro-stepped dielectric material portion overlying stepped surfaces of the alternating stack, a laterally perforated support pillar structure vertically extending through the alternating stack and the retro-stepped dielectric material portion, and a layer contact via structure laterally…

Non-volatile memory with efficient testing during erase

Granted: November 7, 2023
Patent Number: 11810628
When erasing multiple sub-blocks of a block, erase verify is performed for memory cells connected to even word lines to generate even results and for memory cells connected to odd word lines to generate odd results. The even results and the odd results are used to determine that the erase verify process successfully completed. For each NAND string of a first sub-block, a last even result for the NAND string is compared to a last odd result for the NAND string. Despite the determination…

Generating boosted voltages with a hybrid charge pump

Granted: November 7, 2023
Patent Number: 11810626
A hybrid charge pump is disclosed that employs novel arrangements of depletion-mode n-channel semiconductor devices and enhancement-mode p-channel semiconductor devices that eliminate or otherwise substantially reduce voltage drops that would otherwise occur across semiconductor device arrangements in existing charge pumps. As a result, the hybrid charge pump disclosed herein achieves the same output voltages as conventional charge pumps while requiring a reduced physical die area.…

Three-dimensional memory device with wiggled drain-select-level isolation structure and methods of manufacturing the same

Granted: October 31, 2023
Patent Number: 11805649
A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive layers located over a substrate, memory openings vertically extending through the alternating stack, memory opening fill structures located within a respective one of the memory openings, and at least one drain-select-level isolation structure vertically extending through at least a topmost electrically conductive layer among the electrically conductive layers. The at least…

Reference independent and noise insensitive glitch free clock multiplexer

Granted: October 31, 2023
Patent Number: 11803207
Systems and methods disclosed herein provide for an improved glitch-free clock multiplexer exhibiting noise insensitivity with reduced power consumption and reduced physical area on a chip. The embodiments disclosed herein operate without any need of a reference clock. Due to which, clock interchangeability is possible at any point of time. An example glitch-free clock multiplexing according to the embodiments disclosed herein utilize a plurality of clock path circuits, each…

Program dependent biasing of unselected sub-blocks

Granted: October 24, 2023
Patent Number: 11798625
An apparatus includes a control circuit configured to connect to first word lines of a first vertical sub-block and second word lines of a second vertical sub-block. The first vertical sub-block and the second vertical sub-block include memory cells connected in series in NAND strings, each NAND string including memory cells coupled to the first word lines in series with memory cells connected to the second word lines. The control circuit is configured to program or sense memory cells…

Mitigating neighbor interference to select gates in 3D memory

Granted: October 24, 2023
Patent Number: 11798638
Technology for mitigating interference to select transistors in 3D memory is disclosed. In one aspect, a control circuit pre-charges a first set of bit lines to a first voltage and pre-charges a second set of bit lines to a second voltage greater than the first voltage. The control circuit may increase the voltage on the first set of bit lines to the second voltage while the second set of bit lines are floating to couple up the voltages on the second set of bit lines to a voltage greater…

Transfer latch tiers

Granted: October 24, 2023
Patent Number: 11798631
Read and write circuitry, described herein, comprises data latches, each data latch connected to a bit line and arranged in a same column as the bit line; and transfer latches, each transfer latch connected to a data latch and arranged in a same column as the data latch. Further, circuitry described herein is configured to: transfer a word to and from the transfer latches of a first column and the subset of transfer latches of a second column; transfer a first portion of the word between…