摘要:
A multi-headed word line driver circuit incorporates bent-gate transistors to reduce the pitch otherwise achievable for interfacing to tightly-pitched array lines. In certain exemplary embodiments, a three-dimensional memory array includes multiple memory blocks and array lines traversing horizontally across at least one memory block. Vertical active area stripes are disposed beneath a first memory block, and a respective plurality of bent-gate electrodes intersects each respective active area stripe to define individual source/drain regions. Every other source/drain region is coupled to a bias node for the active area stripe, and remaining source/drain regions are respectively coupled to a respective array line associated with the first memory block, thereby forming a respective first driver transistor for the respective array line. In certain embodiments, a respective plurality of complementary array line driver circuits is disposed on each side of a connection area between adjacent memory blocks, and each such driver circuit is responsive to a single driver input node.
摘要:
A nonvolatile memory cell comprising a diode formed of semiconductor material can store memory states by changing the resistance of the semiconductor material by application of a set pulse (decreasing resistance) or a reset pulse (increasing resistance.) In preferred embodiments, set pulses are applied with the diode under forward bias, while reset pulses are applied with the diode in reverse bias. By switching resistivity of the semiconductor material of the diode, a memory cell can be either one-time programmable or rewriteable, and can achieve two, three, four, or more distinct data states.
摘要:
A method and system for forming reversible resistivity-switching elements is described herein. Forming refers to reducing the resistance of the reversible resistivity-switching element, and is generally understood to refer to reducing the resistance for the first time. Prior to forming the reversible resistivity-switching element it may be in a high-resistance state. A first voltage is applied to “partially form” the reversible resistivity-switching element. The first voltage has a first polarity. Partially forming the reversible resistivity-switching element lowers the resistance of the reversible resistivity-switching element. A second voltage that has the opposite polarity as the first is then applied to the reversible resistivity-switching element. Application of the second voltage may further lower the resistance of the reversible resistivity-switching element. Therefore, the second voltage could be considered as completing the forming of the reversible resistivity-switching element.
摘要:
A method and system for forming reversible resistivity-switching elements is described herein. Forming refers to reducing the resistance of the reversible resistivity-switching element, and is generally understood to refer to reducing the resistance for the first time. Prior to forming the reversible resistivity-switching element it may be in a high-resistance state. A first voltage is applied to “partially form” the reversible resistivity-switching element. The first voltage has a first polarity. Partially forming the reversible resistivity-switching element lowers the resistance of the reversible resistivity-switching element. A second voltage that has the opposite polarity as the first is then applied to the reversible resistivity-switching element. Application of the second voltage may further lower the resistance of the reversible resistivity-switching element. Therefore, the second voltage could be considered as completing the forming of the reversible resistivity-switching element.
摘要:
A method and system for forming, resetting, or setting memory cells is disclosed. One or more programming conditions to apply to a memory cell having a reversible resistivity-switching element may be determined based on its resistance. The determination of one or more programming conditions may also be based on a pre-determined algorithm that may be based on properties of the memory cell. The one or more programming conditions may include a programming voltage and a current limit. For example, the magnitude of the programming voltage may be based on the resistance. As another example, the width of a programming voltage pulse may be based on the resistance. In some embodiments, a current limit used during programming is determined based on the memory cell resistance.
摘要:
A method and system for forming, resetting, or setting memory cells is disclosed. One or more programming conditions to apply to a memory cell having a reversible resistivity-switching element may be determined based on its resistance. The determination of one or more programming conditions may also be based on a pre-determined algorithm that may be based on properties of the memory cell. The one or more programming conditions may include a programming voltage and a current limit. For example, the magnitude of the programming voltage may be based on the resistance. As another example, the width of a programming voltage pulse may be based on the resistance. In some embodiments, a current limit used during programming is determined based on the memory cell resistance.
摘要:
A method for using a multi-use memory cell and memory array are disclosed. In one preferred embodiment, a memory cell is operable as a one-time programmable memory cell or a rewritable memory cell. The memory cell comprises a memory element comprising a semiconductor material configurable to one of at least three resistivity states, wherein a first resistivity state is used to represent a data state of the memory cell when the memory cell operates as a one-time programmable memory cell but not when the memory cell operates as a rewritable memory cell. A memory array with such memory cells is also disclosed. In another preferred embodiment, a memory cell is provided comprising a switchable resistance material, wherein the memory cell is operable in a first mode in which the memory cell is programmed with a forward bias and a second mode in which the memory cell is programmed with a reverse bias.
摘要:
A method of programming a nonvolatile memory cell. The nonvolatile memory cell includes a diode steering element in series with a carbon storage element The method includes providing a first voltage to the nonvolatile memory cell. The first voltage reverse biases the diode steering element. The carbon storage element sets to a lower resistivity state.
摘要:
A multi-use memory cell and memory array are disclosed. In one preferred embodiment, a memory cell is operable as a one-time programmable memory cell or a rewritable memory cell. The memory cell comprises a memory element comprising a semiconductor material configurable to one of at least three resistivity states, wherein a first resistivity state is used to represent a data state of the memory cell when the memory cell operates as a one-time programmable memory cell but not when the memory cell operates as a rewritable memory cell. A memory array with such memory cells is also disclosed. In another preferred embodiment, a memory cell is provided comprising a switchable resistance material, wherein the memory cell is operable in a first mode in which the memory cell is programmed with a forward bias and a second mode in which the memory cell is programmed with a reverse bias.
摘要:
A method of programming a monolithic three-dimensional (3-D) memory having a plurality of levels of memory cells above a silicon substrate is disclosed. The method includes initializing a program voltage and program time interval; selecting a memory cell to be programmed within the three-dimensional memory having the plurality of levels of memory cells; applying a pulse having the program voltage and the program time interval to the selected memory cell; performing a read after write operation with respect to the selected memory cell to determine a measured threshold voltage value; and comparing the measured threshold voltage value to a minimum program voltage. In response to the comparison between the measured threshold voltage value and the minimum program voltage, the method further includes selectively applying at least one subsequent program pulse to the selected memory cell.