An ultrathin, carbon-based memristor with a moiré superlattice potential shows prominent ferroelectric resistance switching. The memristor includes a bilayer material, such as Bernal-stacked bilayer graphene, encapsulated between two layers of a layered material, such as hexagonal boron nitride. At least one of the encapsulating layers is rotationally aligned with the bilayer to create the moiré superlattice potential. The memristor exhibits ultrafast and robust resistance switching between multiple resistance states at high temperatures. The memristor, which may be volatile or nonvolatile, may be suitable for neuromorphic computing.

A semiconductor device may include a word line, a bit line crossing the word line, and a memory cell coupled to the word line and the bit line to receive an electrical signal to control the memory cell and including a switching material layer and an oxidation-reduction reversible material layer that is in contact with the switching material layer to allow for either oxidation reaction or reduction reaction to occur in response to different amplitudes and different polarities of the electrical signal, wherein the oxidation-reduction reversible material layer and the switching material layer responds to a first threshold voltage and a first polarity of the electrical signal to generate an oxidation interface between the switching material layer and the oxidation-reduction reversible material layer, and responds to a second threshold voltage and a second polarity of the electrical signal to reduce the generation of the oxidation interface.

A memory device may be provided, including first, second and third electrodes, first and second mask elements and a switching layer. The first mask element may be arranged over a portion of and laterally offset from the first electrode. The second electrode may be arranged over the first mask element. The second mask element may be arranged over the second electrode. The third electrode may be arranged over a portion of and laterally offset from the second mask element. The switching layer may be arranged between the first electrode and the third electrode, along a first side surface of the first mask element, a first side surface of the second electrode and a first side surface of the second mask element.

A computer includes: a memristor array including memristors arranged at intersections between word lines and a first bit line in the memristor array and at intersections between the word lines and second bit lines in the memristor array; an adder circuit configured to obtain sum voltages for the second bit lines by adding first voltages generated according to currents that flow in the second bit lines when a first pattern is supplied to the word lines to difference voltages between a reference voltage generated according to a current that flows in the first bit line when a second pattern is supplied to the word lines and second voltages generated according to currents that flow in the second bit lines when a second pattern is supplied to the word lines; and a detection circuit that detects a second bit line that corresponds to a maximum value of the sum voltages.

An electronic device includes a semiconductor memory. The semiconductor memory includes word lines, bit lines intersecting the word lines, and memory cells coupled to and disposed between the word lines and the bit lines, each of the memory cells including a variable resistance layer in an amorphous state regardless of a value of data stored in the memory cells. In a reset operation, a memory cell is programmed to a high-resistance amorphous state by applying, to the memory cell, a sub-threshold voltage that is lower than a lowest threshold voltage among threshold voltages of the memory cells.

Techniques are provided for programming a self-selecting memory cell that stores a first logic state. To program the memory cell, a pulse having a first polarity may be applied to the cell, which may result in the memory cell having a reduced threshold voltage. During a duration in which the threshold voltage of the memory cell may be reduced (e.g., during a selection time), a second pulse having a second polarity (e.g., a different polarity) may be applied to the memory cell. Applying the second pulse to the memory cell may result in the memory cell storing a second logic state different than the first logic state.

Methods, systems, and devices related to techniques to access a self-selecting memory device are described. A self-selecting memory cell may store one or more bits of data represented by different threshold voltages of the self-selecting memory cell. A programming pulse may be varied to establish the different threshold voltages by modifying one or more time durations during which a fixed level of voltage or current is maintained across the self-selecting memory cell. The self-selecting memory cell may include a chalcogenide alloy. A non-uniform distribution of an element in the chalcogenide alloy may determine a particular threshold voltage of the self-selecting memory cell. The shape of the programming pulse may be configured to modify a distribution of the element in the chalcogenide alloy based on a desired logic state of the self-selecting memory cell.

Provided is a memristor that can be manufactured at a low temperature, and does not include metals of which resources might be depleted. This memristor includes a first electrode, a second electrode, and a memristor layer of an oxide having elements of Ga, Sn, and oxygen, disposed between the first electrode and the second electrode. When voltage is applied to the first electrode with respect to the second electrode, the voltage being positive or negative, a current flows; when voltage of a data-set voltage value is applied, a state is transitioned from a high-resistance state to a low-resistance state; and when voltage of a data-reset voltage value that is of an opposite sign to that of the data-set voltage value is applied, the state is transitioned from a low-resistance state to a high-resistance state.

Techniques are provided for programming a self-selecting memory cell that stores a first logic state. To program the memory cell, a pulse having a first polarity may be applied to the cell, which may result in the memory cell having a reduced threshold voltage. During a duration in which the threshold voltage of the memory cell may be reduced (e.g., during a selection time), a second pulse having a second polarity (e.g., a different polarity) may be applied to the memory cell. Applying the second pulse to the memory cell may result in the memory cell storing a second logic state different than the first logic state.

A resistive random access memory includes a memory cell including a resistive element having a resistance which varies according to a write operation and stores data according to the resistance of the resistive element, a reference resistive element having a resistance set to a first value, a voltage line set to a first voltage during a first write operation in which the resistance of the resistive element is varied from a second value higher than the first value to the first value, and a voltage control circuit arranged between first ends of the two resistive elements. The voltage control circuit adjusts a value of the first voltage supplied from the voltage line so as to reduce a difference between currents flowing through the two resistive elements during the first write operation, and supply the adjusted first voltage to the first ends of the two resistive elements.