An array device and a writing method thereof are provided. A synapse array device includes: a crossbar array, in which a resistive memory element is connected to each intersection of a plurality of row lines and a plurality of column lines; a row select/drive circuit selecting a row line of the crossbar array and applying a pulse signal to the selected row line; a column select/drive circuit selecting a column line of the crossbar array and applying a pulse signal to the selected column line; and a writing part writing to the resistive memory element connected to the selected row line and the selected column line. A first write voltage with controlled pulse width is applied to the selected row line, and a second write voltage with controlled pulse width is applied to the selected column line to perform set writing of the resistive memory element.

According to one embodiment, a semiconductor memory device includes: a first and a second wirings; a third wiring disposed between them; a first phase change layer disposed between the first and the third wirings; a first conducting layer disposed on a first wiring side surface of the first phase change layer; a second conducting layer disposed on a third wiring side surface of the first phase change layer; a second phase change layer disposed between the third and the second wirings; a third conducting layer disposed on a third wiring side surface of the second phase change layer; and a fourth conducting layer disposed on a second wiring side surface of the second phase change layer. The first and the fourth conducting layers have coefficients of thermal conductivity larger or smaller than the coefficients of thermal conductivity of the second and the third conducting layers.

Various embodiments of the present application are directed towards a method of forming a memory device. The method includes forming a lower part of an interconnect structure over a substrate and forming a unipolar selector over the lower part of the interconnect structure. The method further comprises forming a data-storage element over the unipolar selector and electrically coupled in series with the unipolar selector, the data-storage element having a variable resistance. The method further comprises generating an external magnetic field by a magnetic field generator to pre-set the data-storage element to a first data state.

A memory device includes a cell region including a plurality of word lines, a plurality of bit lines, and a plurality of memory cells connected to the plurality of word lines and the plurality of bit lines disposed therein, where each of the plurality of memory cells includes a switch element and a memory element connected to each other in series between a corresponding word line and a corresponding bit line, and a peripheral circuit region including a control logic configured to, when a read command for a selected memory cell among the memory cells is received from an external controller, input a pre-voltage to the selected memory cell before reading data of the selected memory cell. The control logic is configured to determine a level of the pre-voltage with reference to an elapsed time after programming of the selected memory cell.

A variable resistance memory device includes: a memory cell including a first and second sub memory cell; and a first, second and third conductor. The first sub memory cell is above the first conductor, and includes a first variable resistance element and a first bidirectional switching element. The second sub memory cell is above the second conductor, and includes a second variable resistance element and a second bidirectional switching element. The second conductor is above the first sub memory cell. The third conductor is above the second sub memory cell. The variable resistance memory device is configured to receive first data and to write the first data to the memory cell when the first data does not match second data read from the memory cell.

A memory device includes a plurality of memory cells, each including a switching device and an information storage device connected to the switching device and having a phase change material, the plurality of memory cells connected to a plurality of word lines and a plurality of bit lines, a decoder circuit determining at least one of the plurality of memory cells to be a selected memory cell, and a program circuit configured to input a programming current to the selected memory cell to perform a programming operation and configured to detect a resistance of the selected memory cell to adjust a magnitude of the programming current.

A semiconductor device is provided. The semiconductor device includes a substrate a substrate, a first electrode structure on the substrate, the first electrode structure including first insulating patterns and first electrode patterns, the first insulating patterns alternately stacked with the first electrode patterns, a second electrode pattern on a sidewall of the first electrode structure, and a data storage film on a sidewall of the second electrode pattern. The data storage film has a variable resistance.

A variable resistance nonvolatile storage device includes: a variable resistance element having a state reversibly changeable between a high resistance state and a low resistance state; and a current supply circuit that supplies the variable resistance element with a low-resistance changing current for changing the state from the high resistance state to the low resistance state. The low-resistance changing current has a waveform that includes a first period and a second period along a time axis, the second period being subsequent to the first period. The current supply circuit applies to the variable resistance element: a first current during the first period; and a second current during the second period, the second current being smaller than the first current. The first current is not zero at an end of the first period, and the second current is not zero at a start of the second period.

A semiconductor memory device has a first wiring extending in a first direction and a second wiring extending in a second direction. The first and second wirings are spaced from each other in a third direction. The second wiring has a first recess facing the first wiring. A resistance change memory element is connected between the first and second wirings. A conductive layer is between the resistance change memory element and the second wiring and includes a first protrusion facing the second wiring. A switching portion is between the conductive layer and the second wiring and includes a second recess facing the conductive layer and a second protrusion facing the second wiring. The first protrusion is in the second recess. The second protrusion is in the first recess. The switching portion is configured to switch conductivity state according to voltage between the first wiring and the second wiring.

A writing method for a non-volatile memory device includes; performing a sensing operation, comparing write data with read data retrieved by the sensing operation, determining whether the write data is set state when the write data and the read data are the same, performing a set operation when the write data is set state, and not performing a write operation when the write data is not set data.