Patent application number | Description | Published |
20130301339 | SEMICONDUCTOR MEMORY DEVICE - A control circuit controls a voltage applied to a memory cell array. A first electrode contacts to a first surface of a variable resistance element, while a second electrode contacts to a second surface of the variable resistance element. The first electrode is configured by a metal, and the second electrode is configured by a P type semiconductor. The control unit, when performing a setting operation of a memory cell, applies a voltage such that a current flows in a direction from the first electrode toward the second electrode. | 11-14-2013 |
20140036571 | SEMICONDUCTOR MEMORY DEVICE AND OPERATION METHOD THEREOF - A semiconductor memory device according to an embodiment includes a control circuit configured to apply a first voltage to a selected first line, apply a second voltage to a selected second line, and apply a third voltage and a fourth voltage to a non-selected first line and a non-selected second line in a setting operation, respectively. The control circuit includes a detection circuit configured to detect a transition of a resistance state of a selected memory cell using a reference voltage. The control circuit is configured to execute a read operation in which the control circuit applies the third voltage to the selected first line and the non-selected first line, applies the second voltage to the selected second line, and applies the fourth voltage to the non-selected second line, and set the reference voltage based on a voltage value of the selected second line. | 02-06-2014 |
20140061578 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - A nonvolatile semiconductor memory device below comprises: a memory cell array configured having memory cells arranged therein disposed at intersections of a plurality of first lines and a plurality of second lines formed so as to intersect each other, and the memory cells each comprising a variable resistance element; and a control circuit configured to select and drive the first lines and the second lines. The variable resistance element is configured by a transition metal oxide film. The variable resistance element is electrically connected to a first electrode configured from a metal at a first surface and is electrically connected to a second electrode at a second surface which is on an opposite side to the first surface. A first insulating film is formed between the first electrode and the variable resistance element. The first insulating film is formed by a first material that is formed by covalent binding. | 03-06-2014 |
20140209853 | SEMICONDUCTOR MEMORY DEVICE - A plurality of first conductive layers are stacked at a predetermined pitch in a first direction perpendicular to a substrate. A memory layer is provided in common on side surfaces of the first conductive layers and functions as the memory cells. A second conductive layer comprises a first side surface in contact with side surfaces of the first conductive layers via the memory layer, the second conductive layer extending in the first direction. A width in a second direction of the first side surface at a first position is smaller than a width in the second direction of the first side surface at a second position lower than the first position. A thickness in the first direction of the first conductive layer at the first position is larger than a thickness in the first direction of the first conductive layer at the second position. | 07-31-2014 |
20140241037 | SEMICONDUCTOR MEMORY DEVICE - A memory cell array includes first wiring lines, and second wiring lines, the first and second wiring lines intersecting, and memory cells disposed in the intersections of the first and second wiring lines, the memory cells including a variable resistance element. A control circuit controls voltages of selected first and second wiring lines. The first wiring lines are arranged at a first pitch in a first direction perpendicular to a substrate and extend in a second direction parallel to the substrate. The second wiring lines are arranged at a second pitch in the second direction and extend in the first direction. The control circuit is configured to change voltages applied to a selected first wiring line according to the positions of the selected first wiring lines in the first direction. | 08-28-2014 |
20150060749 | NONVOLATILE MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - According to an embodiment, a first impurity diffusion layer is provided in a region lower than a drain region and the first impurity diffusion layer diffuses impurities of a second conductivity type. A second impurity diffusion layer is provided between the drain region and the first impurity diffusion layer, and the second impurity diffusion layer diffuses impurities of a first conductivity type or the second conductivity type, and a concentration of the second impurity diffusion layer is lower than that of the first conductivity type of the drain region and that of the second conductivity type of the first impurity diffusion layer. | 03-05-2015 |
20150194210 | SEMICONDUCTOR MEMORY DEVICE AND OPERATION METHOD THEREOF - A semiconductor memory device according to an embodiment includes a control circuit configured to apply a first voltage to a selected first line, apply a second voltage to a selected second line, and apply a third voltage and a fourth voltage to a non-selected first line and a non-selected second line in a setting operation, respectively. The control circuit includes a detection circuit configured to detect a transition of a resistance state of a selected memory cell using a reference voltage. The control circuit is configured to execute a read operation in which the control circuit applies the third voltage to the selected first line and the non-selected first line, applies the second voltage to the selected second line, and applies the fourth voltage to the non-selected second line, and set the reference voltage based on a voltage value of the selected second line. | 07-09-2015 |
20150207071 | RESISTIVE RANDOM ACCESS MEMORY DEVICE AND MANUFACTURING METHOD OF RESISTIVE ELEMENT FILM - In accordance with an embodiment, a manufacturing method of a resistive element film includes sequentially repeating, a desired number of times, first and second film formation cycles. In the first film formation cycle, an insulating film is formed up to a continuous layer by an ALD film formation method under a first condition. In the second film formation cycle a metal film is formed on the insulating film up to a continuous layer by the ALD film formation method under a second condition. | 07-23-2015 |