Methods, systems, and devices for memory arrays having graded memory stack resistances are described. An apparatus may include a first subset of memory stacks having a first resistance based on a physical and/or electrical distance of the first subset of memory stacks from at least one of a first driver component or a second driver component. The apparatus may include a second subset of memory stacks having a second resistance that is less than the first resistance based on a physical and/or electrical distance of the second subset of memory from at least one of the first driver component or the second driver component.

Noise injection systems and methods for conducting power noise susceptibility tests on memory systems, including solid state drives. A noise injection system comprises a power selector to deliver a voltage at a first or second level according to a frequency level indicated by a frequency select signal; a noise signal relay to receive a frequency noise signal and to deliver a low or high frequency noise component of the frequency noise signal according to the frequency level of the frequency select signal; and an amplification assembly, responsive to the frequency select signal and which receives the first or second level voltage based on the frequency level of the frequency select signal, receives and amplifies the high frequency noise component when the frequency select signal indicates a high frequency level, and receives and amplifies the low frequency noise component when the frequency select signal indicates a low frequency level.

This application provides a memory, a chip, and a method for storing repair information of the memory. The memory includes a repair circuit that is configured to receive a first signal from a processor and determine to be powered by a first power supply or a second power supply based on a status of the first signal, to store repair information. The repair information is information of the failed bit cells in the memory. The first power supply is zero or in a high impedance state when a system is powered off, and the second power supply is not zero when the system is powered off. The memory further comprises a processing circuit configured to perform communication between the memory and the processor based on the repair information. Therefore, the repair information of the memory can be stored even during power loss.

A test structure for 3D memory arrays and methods of forming the same are disclosed. In an embodiment, a memory array includes a first word line over a semiconductor substrate and extending in a first direction; a second word line over the first word line and extending in the first direction; a memory film contacting the first word line and the second word line; an oxide semiconductor (OS) layer contacting a first source line and a first bit line, the memory film being between the OS layer and each of the first word line and the second word line; and a test structure over the first word line and the second word line, the test structure including a first conductive line electrically coupling the first word line to the second word line, the first conductive line extending in the first direction.

A row decoder located on one side of a memory array selectively drives word lines in response to a row address. A word line fault detection circuit located on an opposite side of the first memory array operates to detect an open word line fault between the opposed sides of the memory array. The word line fault detection circuit includes a first clamp circuit that operates to clamp the word lines to ground. An encoder circuit encodes signals on the word lines to generate an encoded address. The encoded address is compared to the row address by a comparator circuit which sets an error flag indicating the open word line fault has been detected if the encoded address does not match the row address.

Embodiments of the present disclosure provide a method and an apparatus of testing a word line. After repair of a memory array is completed, if a target word line in a failure state exists in the memory array, a second numerical value is written into the target word line, and then it is determined, according to a numerical value outputted by each word line in the memory array, whether there are at least two word lines in an on-state in the memory array; if there are at least two word lines in an on-state simultaneously in the memory array, a current value generated by the target word line in an on-to-off process is detected; when the current value generated by the target word line in the on-to-off process is greater than a preset current threshold, it is determined that the target word line has a repair fault.

Methods, systems, and devices for charge leakage detection for memory system reliability are described. In accordance with examples as disclosed herein, a memory system may employ memory management techniques configured to identify precursors of charge leakage in a memory device, and take preventative action based on such identified precursors. For example, a memory system may be configured to perform a leakage detection evaluation for a memory array, which may include various biasing and evaluation operations to identify whether a leakage condition of the memory array may affect operational reliability. Based on such an evaluation, the memory device, or a host device in communication with the memory device, may take various preventative measures to avoid operational failures of the memory device or host device that may result from ongoing operation of a memory array associated with charge leakage, thereby improving reliability of the memory system.

Methods, systems, and devices related to access schemes for access line faults in a memory device are described. In one example, a method may include isolating a first word line of a section of a memory device from a voltage source (e.g., a deselection voltage source) during a first portion of a period when the first word line is deselected, and coupling the first word line with the voltage source during a second portion of the period when the first word line is deselected based on determining that an access operation is performed during the second portion of the period when the word line is deselected. In some examples, the method may include identifying that the first word line is associated with a fault, such as a short circuit fault with a digit line of the memory device.

The present disclosure provides a method for detecting a memory and a device for detecting a memory. The memory includes first memory cells, second memory cells, bit lines, complementary bit lines, word lines, and a plurality of sense amplifiers, where each of the sense amplifiers is electrically coupled to a bit line and a complementary bit line; and the method includes: writing storage data into each of the first memory cells and each of the second memory cells; performing a read operation; obtaining a test result based on a difference between real data and the storage data; and obtaining a leakage position of the bit line and the word line or a leakage position the complementary bit line and the word line based on the test result.

Methods, systems, and devices for timing signal delay compensation in a memory device are described. In some memory devices, operations for accessing memory cells may be performed with timing that is asynchronous relative to an input signal. To support asynchronous timing, a memory device may include delay components that support generating a timing signal having aspects that are delayed relative to an input signal. In accordance with examples as disclosed herein, a memory device may include delay components having a variable and configurable impedance, where the configurable impedance may be based at least in part on a configuration signal generated at the memory device. A configuration signal may be generated based on fabrication characteristics of the memory device, or based on operating conditions of the memory device, or various combinations thereof.