Patent application number | Description | Published |
20090201717 | RESISTANCE-CHANGE MEMORY - A resistance-change memory includes first and second bit lines running in the same direction, a third bit line running parallel to the first and second bit lines, fourth and fifth bit lines running in the same direction, a sixth bit line running parallel to the fourth and fifth bit lines, a first memory element which has one and the other terminals connected to the first and third bit lines, and changes to one of first and second resistance states, a first reference element having one and the other terminals connected to the fourth and sixth bit lines, and set in the first resistance state, a second reference element having one and the other terminals connected to the fifth and sixth bit lines, and set in the second resistance state, and a sense amplifier having first and second input terminals connected to the first and fourth bit lines. | 08-13-2009 |
20100124116 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - Memory strings includes: a first semiconductor layer including a columnar portion extending in a direction perpendicular to a substrate; a first electric charge storage layer formed to surround a side surface of the columnar portion; and a first conductive layer formed to surround the first electric charge storage layer. First selection transistors includes: a second semiconductor layer extending upward from a top surface of the columnar portion; a second electric charge storage layer formed to surround a side surface of the second semiconductor layer; and a second conductive layer formed to surround the second electric charge storage layer. The non-volatile semiconductor storage device further includes a control circuit that causes, prior to reading data from a selected one of the memory strings, electric charges to be accumulated in the second electric charge storage layer of one of the first selection transistors connected to an unselected one of the memory strings. | 05-20-2010 |
20100172189 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - A non-volatile semiconductor storage device includes: a memory string including a plurality of memory cells connected in series; a first selection transistor having one end connected to one end of the memory string; a first wiring having one end connected to the other end of the first selection transistor; a second wiring connected to a gate of the first selection transistor. A control circuit is configured to boost voltages of the second wiring and the first wiring in the erase operation, while keeping the voltage of the first wiring greater than the voltage of the second wiring by a certain potential difference. The certain potential difference is a potential difference that causes a GIDL current. | 07-08-2010 |
20100214838 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - A non-volatile semiconductor storage device includes a control circuit performing an erase operation to erase data from a selected one of memory transistors. The control circuit applies a first voltage to the other end of selected one of selection transistors, causes the selected one of the selection transistors to turn on, and causes any one of the memory transistors to turn on that is closer to the selection transistor than the selected one of the memory transistors. The control circuit also applies a second voltage lower than the first voltage to a gate of the selected one of the memory transistors. Such a potential difference between the first voltage and the second voltage causing a change in electric charges in the electric charge storage layer. | 08-26-2010 |
20100232224 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - A memory cell array has plural memory strings arranged therein, each of which including a plurality of electrically-rewritable memory transistors and selection transistors. Each memory string includes a body semiconductor layer including four or more columnar portions, and a joining portion formed to join the lower ends thereof. An electric charge storage layer is formed to surround a side surface of the columnar portions. A first conductive layer is formed to surround a side surface of the columnar portions as well as the electric charge storage layer. A plurality of second conductive layers are formed on side surfaces of the joining portion via an insulation film, and function as control electrodes of a plurality of back-gate transistors formed at a respective one of the joining portions. | 09-16-2010 |
20110063916 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - At least some of the memory transistors included in a first memory string are commonly connected to first conductive layers that are connected to at least some of the memory transistors included in a second memory string connected to the same third and fourth conductive layers as the first memory string. At least one of either the memory transistors or the back-gate transistor in the first memory string and at least one of either the memory transistors or the back-gate transistor in the second memory string are connected to the independent first or fifth conductive layers, respectively. | 03-17-2011 |
20120176836 | NON-VOLATILE SEMICONDUCTOR MEMORY DEVICE - According to one embodiment, a non-volatile semiconductor memory device comprises memory strings. Each memory string comprises a semiconductor layer, control gates, a first selection gate, and a second selection gate. A semiconductor layer comprises a pair of pillar portions which extend in a vertical direction to a substrate, and a coupling portion formed to couple the pair of pillar portions. Control gates orthogonally intersect one of the pair of pillar portions or the other of the pair of pillar portions. A first selection gate orthogonally intersects one of the pair of pillar portions and is formed above the control gates. A second selection gate orthogonally intersects the other of the pair of pillar portions, is formed above the control gates, and is on the same level as the first selection gate as well as integrated with the first selection gate. | 07-12-2012 |
20120218821 | NON-VOLATILE SEMICONDUCTOR STORAGE DEVICE - A non-volatile semiconductor storage device includes: a memory string including a plurality of memory cells connected in series; a first selection transistor having one end connected to one end of the memory string; a first wiring having one end connected to the other end of the first selection transistor; a second wiring connected to a gate of the first selection transistor. A control circuit is configured to boost voltages of the second wiring and the first wiring in the erase operation, while keeping the voltage of the first wiring greater than the voltage of the second wiring by a certain potential difference. The certain potential difference is a potential difference that causes a GIDL current. | 08-30-2012 |
20120243314 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - A nonvolatile semiconductor memory device according to one aspect includes a semiconductor substrate, a memory string, a plurality of first conductive layers, a second conductive layer, and a third conductive layer. The memory string has a plurality of memory cells, a dummy transistor and a back gate transistor connected in series in a direction perpendicular to the semiconductor substrate. The plurality of first conductive layers are electrically connected to gates of the memory cells. The second conductive layer is electrically connected to a gate of the dummy transistor. The third conductive layer is electrically connected to a gate of the back gate transistor. The second conductive layer is short-circuited with the third conductive layer. | 09-27-2012 |
20120243326 | SEMICONDUCTOR STORAGE DEVICE - According to one embodiment, a device includes transistors each with a path connected to a bit line, and circuits each includes a switch, the circuit being connected to the bit line. The device includes a amplifier connected to the transistor and to the circuit, and a latch connected to the amplifier to hold first data before read is carried out on a cell and to hold second data if a current equal to or a larger than a predetermined value flows via the bit line. In the device, the switch is turned on or off depending on data held in another latch located adjacently in a direction of the word lines, to control a connection between the bit line and connected to another bit line the amplifier via the circuit. | 09-27-2012 |
20130070528 | SEMICONDUCTOR MEMORY DEVICE - According to one embodiment, a semiconductor memory device includes a memory cell array, a bit line, a source line, and a sense circuit. The memory cell array includes memory strings which include memory cells connected in series and stacked above a semiconductor substrate. The bit line is coupled to one of the memory strings and is capable of transferring data. The source line is coupled to one of the memory strings. When data is read, a read current flows from a bit line into the source line. The sense circuit is coupled to the bit line and senses read data. An operation timing of the sense circuit is determined on the basis of a current flowing through the source line. | 03-21-2013 |
20130336064 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - When selectively erasing one sub-block, a control circuit applies, in a first sub-block, a first voltage to bit lines and a source line, and applies a second voltage smaller than the first voltage to the word lines. Then, the control circuit applies a third voltage lower than the first voltage by a certain value to a drain-side select gate line and a source-side select gate line, thereby performing the erase operation in the first sub-block. The control circuit applies, in a second sub-block existing in an identical memory block to the selected sub-block, a fourth voltage substantially identical to the first voltage to the drain side select gate line and the source side select gate line, thereby not performing the erase operation in the second sub-block. | 12-19-2013 |
20140092684 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - When selectively erasing one sub-block, a control circuit applies, in a first sub-block, a first voltage to bit lines and a source line, and applies a second voltage smaller than the first voltage to the word lines. Then, the control circuit applies a third voltage lower than the first voltage by a certain value to a drain-side select gate line and a source-side select gate line, thereby performing the erase operation in the first sub-block. The control circuit applies, in a second sub-block existing in an identical memory block to the selected sub-block, a fourth voltage substantially identical to the first voltage to the drain side select gate line and the source side select gate line, thereby not performing the erase operation in the second sub-block. | 04-03-2014 |