Patent application number | Description | Published |
20090323426 | SEMICONDUCTOR MEMORY DEVICE - A semiconductor memory device includes a sense amplifier which senses identical multilevel data, which is stored in a memory cell, a plurality of number of times at a time of read, and a n-channel MOS transistor which has a current path one end of which is connected to the sense amplifier and the other end of which is connected to a bit line. The device further include a control unit which applies a first voltage to a gate electrode of the n-channel MOS transistor, thereby setting the n-channel MOS transistor in an ON state, and applies a second voltage which is higher than the first voltage, to the gate electrode during a period after first sense and before second sense. | 12-31-2009 |
20100034020 | SEMICONDUCTOR MEMORY DEVICE INCLUDING CHARGE STORAGE LAYER AND CONTROL GATE - A semiconductor memory device includes a plurality of memory cells, signal lines, and a control unit. Each of the plurality of memory cells includes a charge storage layer. Each of the plurality of memory cells includes a control gate and is configured to hold two-or-higher-level data. Each of signal lines is electrically connected with a gate or one end of a current path of each of the memory cells. Each of signal lines has a line width which differs depending on each interval between the memory cells adjacent to each other. The control unit controls a voltage applied to each of the signal lines in accordance with the line width of each of the signal lines. | 02-11-2010 |
20100084702 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - A nonvolatile semiconductor memory device comprises a memory cell configured to store data and a resistor element provided around the memory cell. The memory cell includes a charge storage layer provided above a substrate, a first semiconductor layer formed on a top surface of the charge storage layer via an insulating layer, and a first low resistive layer formed on a top surface of the first semiconductor layer and having resistance lower than that of the first semiconductor layer. The resistor element includes a second semiconductor layer formed on the same layer as the first semiconductor layer, and a second low resistive layer formed on the same layer as the first low resistive layer and on a top surface of the second semiconductor layer, having resistance lower than that of the second semiconductor layer. The second semiconductor layer is formed to extend in a first direction parallel to the substrate. The second low resistive layer is formed at both ends of the second semiconductor layer in the first direction. | 04-08-2010 |
20100322012 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE AND WRITE METHOD FOR THE SAME - According to one embodiment, a semiconductor device includes memory cells, bit lines, a write circuit, and sense amplifiers. The bit lines are connected to the memory cells. The sense amplifiers are configured to bias the bit line to which the selected memory cell is connected, to a first voltage until the threshold of the selected memory cell reaches the value of a first write state. Then, when the threshold of the selected memory cell reaches the value of the first write state, the bit line is biased to a second voltage higher than the first voltage. When the threshold of the selected memory cell reaches the value of a second write state, the bit line is continuously biased to a third voltage higher than the second voltage. Bit lines connected to unselected memory cells corresponding to the memory cells other than the selected one are biased to the third voltage. | 12-23-2010 |
20110063922 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE - Nonvolatile semiconductor memory device according to one embodiment includes: a plurality of planes; a memory cell array provided in the plurality of planes respectively; bit lines; and a control circuit. Each memory cell array is configured as an array of NAND cell units each including a memory string. The memory string includes a plurality of nonvolatile memory cells connected in series. The bit lines are connected to a first end of the NAND cell units, respectively. The control circuit controls a write operation of charging the bit lines up to a certain voltage value, and then setting data in the nonvolatile memory cells to a certain threshold voltage distribution state. The control circuit is configured to be capable of executing an operation of charging the bit lines in a write operation by varying timings of starting charging the bit lines among the plurality of planes. | 03-17-2011 |
20110090736 | SEMICONDUCTOR MEMORY DEVICE - A semiconductor memory device includes a sense amplifier which senses identical multilevel data, which is stored in a memory cell, a plurality of number of times at a time of read, and a n-channel MOS transistor which has a current path one end of which is connected to the sense amplifier and the other end of which is connected to a bit line. The device further include a control unit which applies a first voltage to a gate electrode of the n-channel MOS transistor, thereby setting the n-channel MOS transistor in an ON state, and applies a second voltage which is higher than the first voltage, to the gate electrode during a period after first sense and before second sense. | 04-21-2011 |
20110176366 | SEMICONDUCTOR STORAGE DEVICE AND READING METHOD THEREOF - An embodiment of the invention provides a semiconductor storage device including a NAND string, a SEN node, and a capacitor. The NAND string includes plural series-connected memory cells, and one end of the NAND string is connected to a bit line while the other end is connected to a common source line. The SEN node is configured to be able to be electrically connected to a voltage source and the bit line. In the capacitor, one end is connected to the SEN node while the other end is connected to a CLK node to which a voltage within a predetermined range is applied. A discharge rate of the SEN node is enhanced by decreasing a capacitance during discharge of the SEN node only when a selected memory cell selected from the plural memory cells is an on-cell. | 07-21-2011 |
20120168851 | NONVOLATILE SEMICONDUCTOR MEMORY DEVICE AND METHOD OF MANUFACTURING THE SAME - A nonvolatile semiconductor memory device including a memory cell configured to store data and a resistor element provided around the memory cell. The memory cell includes a charge storage layer provided above a substrate, a first semiconductor layer formed on a top surface of the charge storage layer via an insulating layer, and a first low resistive layer formed on a top surface of the first semiconductor layer and having resistance lower than that of the first semiconductor layer. The resistor element includes a second semiconductor layer formed on the same layer as the first semiconductor layer, and a second low resistive layer formed on the same layer as the first low resistive layer and on a top surface of the second semiconductor layer, having resistance lower than that of the second semiconductor layer. | 07-05-2012 |