摘要:
A nonvolatile memory device of the present invention includes a substrate (1), first wires (3), first resistance variable elements (5) and lower electrodes (6) of first diode elements which are filled in first through-holes (4), respectively, second wires (11) which cross the first wires 3 perpendicularly to the first wires 3, respectively, and each of which includes a semiconductor layer (7) of a first diode elements, a conductive layer (8) and a semiconductor layer (10) of a second diode elements which are stacked together in this order, second resistance variable elements (16) and upper electrodes (14) of second diode elements which are filled into second through holes (13), respectively, and third wires (17), and the conductive layer (8) of each second wires (11) also serves as the upper electrode of the first diode elements (9) and the lower electrode of the second diode elements (15).
摘要:
A nonvolatile memory device of the present invention comprises a substrate (1), first wires (3), first filling constituents (5) filled into first through-holes (4), respectively, second wires (11) which cross the first wires (3) perpendicularly to the first wires (3), respectively, each of the second wires (11) including a plurality of layers including a resistance variable layer (6) of each of first resistance variable elements, a conductive layer (7) and a resistance variable layer (8) of each of second resistance variable elements which are stacked together in this order, second filling constituents (14) filled into second through-holes (13), respectively, and third wires (15), and the conductive layer (7) of the second wires (11) serves as the electrodes of the first resistance variable elements (9) and the electrodes of the second resistance variable elements (10).
摘要:
A nonvolatile memory device of the present invention comprises a substrate (1), first wires (3), first filling constituents (5) filled into first through-holes (4), respectively, second wires (11) which cross the first wires (3) perpendicularly to the first wires (3), respectively, each of the second wires (11) including a plurality of layers including a resistance variable layer (6) of each of first resistance variable elements, a conductive layer (7) and a resistance variable layer (8) of each of second resistance variable elements which are stacked together in this order, second filling constituents (14) filled into second through-holes (13), respectively, and third wires (15), and the conductive layer (7) of the second wires (11) serves as the electrodes of the first resistance variable elements (9) and the electrodes of the second resistance variable elements (10).
摘要:
A nonvolatile memory device of the present invention includes a substrate (1), first wires (3), first resistance variable elements (5) and lower electrodes (6) of first diode elements which are filled in first through-holes (4), respectively, second wires (11) which cross the first wires 3 perpendicularly to the first wires 3, respectively, and each of which includes a semiconductor layer (7) of a first diode elements, a conductive layer (8) and a semiconductor layer (10) of a second diode elements which are stacked together in this order, second resistance variable elements (16) and upper electrodes (14) of second diode elements which are filled into second through holes (13), respectively, and third wires (17), and the conductive layer (8) of each second wires (11) also serves as the upper electrode of the first diode elements (9) and the lower electrode of the second diode elements (15).
摘要:
A variable resistance nonvolatile memory device including memory cells provided at cross-points of first signal lines and second signal lines, each memory cell including a variable resistance element and a current steering element connected to the variable resistance element in series, the variable resistance nonvolatile memory device including a write circuit, a row selection circuit, and a column selection circuit, wherein the write circuit: sequentially selects blocks in an order starting from a block farthest from at least one of the row selection circuit and the column selection circuit and finishing with a block closest to the at least one of the row selection circuit and the column selection circuit; and performs, for each of the selected blocks, initial breakdown on each memory cell included in the selected block.
摘要:
A cross point variable resistance nonvolatile memory device including: a cross point memory cell array having memory cells each of which is placed at a different one of cross points of bit lines and word lines; a word line decoder circuit that selects at least one of the memory cells from the memory cell array; a read circuit that reads data from the selected memory cell; an unselected word line current source that supplies a first constant current; and a control circuit that controls the reading of the data from the selected memory cell, wherein the control circuit controls the word line decoder circuit, the read circuit, and the unselected word line current source so that when the read circuit reads data, the first constant current is supplied to an unselected word line.
摘要:
To provide a variable resistance element writing method that, even when a variable resistance element has a possibility of becoming a half LR state, can ensure a maximum resistance change window by correcting the variable resistance element to a normal low resistance state. In a method of writing data to a variable resistance element (10a) that reversibly changes between a high resistance state and a low resistance state according to a polarity of an applied voltage, as a voltage applied to an upper electrode (11) with respect to a lower electrode (14t): a positive voltage is applied in a high resistance writing step (405) to set the variable resistance element (10a) to a high resistance state (401); a negative voltage is applied in a low resistance writing step (406, 408) to set the variable resistance element (10a) to a low resistance state (403, 402); and a positive voltage is applied in a low resistance stabilization writing step (404) after the negative voltage is applied in the low resistance writing step (408), thereby setting the variable resistance element (10a) through the low resistance state to the high resistance state (401).
摘要:
A nonvolatile resistance variable memory device (100) includes memory cells (M11, M12, . . . ) in each of which a variable resistance element (R11, R12, . . . ) including a variable resistance layer placed between and in contact with a first electrode and a second electrode, and a current steering element (D11, D12, . . . ) including a current steering layer placed between and in contact with a third electrode and a fourth electrode, are connected in series, and the device is driven by a first LR drive circuit (105a1) via a current limit circuit (105b) to decrease resistance of the variable resistance element while the device is driven by a second HR drive circuit (105a2) to increase resistance of the variable resistance element, thus using the current limit circuit (105b) to make a current for decreasing resistance of the variable resistance element lower than a current for increasing resistance of the variable resistance element.
摘要:
A cross point nonvolatile memory device capable of suppressing sneak-current-caused reduction in sensitivity of detection of a resistance value of a memory element is provided. The device includes perpendicular bit and word lines; a cross-point cell array including memory cells each having a resistance value reversibly changing between at least two resistance states according to electrical signals, arranged on cross-points of the word and bit lines; an offset detection cell array including an offset detection cell having a resistance higher than that of the memory cell in a high resistance state, the word lines being shared by the offset detection cell array; a read circuit (a sense amplifier) that determines a resistance state of a selected memory cell based on a current through the selected bit line; and a current source which supplies current to the offset detection cell array in a read operation period.
摘要:
A writing method optimum for a variable resistance element which can maximize an operation window of the variable resistance element is provided. The writing method is performed for a variable resistance element that reversibly changes between a high resistance state and a low resistance state depending on a polarity of an applied voltage pulse. The writing method includes a preparation step (S50) and a writing step (S51, S51a, S51b). At the preparation step (S50), resistance values of the variable resistance element are measured by applying voltage pulses of voltages that are gradually increased to the variable resistance element, thereby determining the first voltage V1 for starting high resistance writing and the second voltage V2 having a maximum resistance value. At the HR writing step (S51a), a voltage pulse having a voltage Vp that is equal to or higher than the first voltage V1 and equal to or lower than the second voltage V2 is applied to the variable resistance element, thereby changing the variable resistance element from the low resistance state (S52) to the high resistance state (S53).