Patent application number | Description | Published |
20090283736 | NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR APPARATUS USING THE NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element comprises a first electrode layer ( | 11-19-2009 |
20100271860 | DRIVING METHOD OF VARIABLE RESISTANCE ELEMENT, INITIALIZATION METHOD OF VARIABLE RESISTANCE ELEMENT, AND NONVOLATILE STORAGE DEVICE - A method of driving a variable resistance element includes: a writing step performed by applying a writing voltage pulse having a first polarity to a variable resistance layer to change a resistance state of the layer from high to low; and an erasing step performed by applying an erasing voltage pulse having a second polarity to the layer to change the state from low to high. Here, |Vw1|>|Vw2| where Vw1 represents a voltage value of the writing voltage pulse for first to N-th writing steps (N≧ | 10-28-2010 |
20110002154 | NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR DEVICE INCORPORATING NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element of the present invention comprises a first electrode ( | 01-06-2011 |
20110031465 | RESISTANCE VARIABLE ELEMENT AND MANUFACTURING METHOD THEREOF - A resistance variable element of the present invention comprises a first electrode ( | 02-10-2011 |
20110044088 | VARIABLE RESISTANCE NONVOLATILE STORAGE DEVICE AND METHOD OF FORMING MEMORY CELL - A variable resistance nonvolatile storage device which includes (i) a semiconductor substrate ( | 02-24-2011 |
20110080770 | METHOD OF PROGRAMMING VARIABLE RESISTANCE ELEMENT AND NONVOLATILE STORAGE DEVICE - Applying a writing voltage pulse having a first polarity to a metal oxide layer ( | 04-07-2011 |
20110103131 | NONVOLATILE MEMORY ELEMENT AND NONVOLATILE MEMORY DEVICE - Provided is a nonvolatile memory element which has a small variation in operation and allow stable operation. The nonvolatile memory element includes: a first electrode ( | 05-05-2011 |
20110233510 | NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element of the present invention comprises a first electrode ( | 09-29-2011 |
20110294259 | NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR APPARATUS USING THE NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element comprises a first electrode layer ( | 12-01-2011 |
20120170353 | NONVOLATILE MEMORY DEVICE AND METHOD FOR PROGRAMMING THE SAME - A method for programming a nonvolatile memory device according to the present invention includes a step of detecting an excessively low resistance cell from among a plurality of memory cells ( | 07-05-2012 |
20120230085 | FORMING METHOD OF PERFORMING FORMING ON VARIABLE RESISTANCE NONVOLATILE MEMORY ELEMENT, AND VARIABLE RESISTANCE NONVOLATILE MEMORY DEVICE - In forming, an automatic forming circuit ( | 09-13-2012 |
20120320661 | METHOD OF PROGRAMMING VARIABLE RESISTANCE ELEMENT AND NONVOLATILE STORAGE DEVICE - A method includes applying a first polarity writing voltage pulse to a metal oxide layer to change its resistance state from high to low into a write state, applying a second polarity erasing voltage pulse different from the first polarity to the metal oxide layer to change its resistance state from low to high into an erase state, and applying an initial voltage pulse having the second polarity to the metal oxide layer before first application of the writing voltage pulse, to change an initial resistance value of the metal oxide layer. R | 12-20-2012 |
20130010530 | METHOD FOR DRIVING NON-VOLATILE MEMORY ELEMENT, AND NON-VOLATILE MEMORY DEVICE - Provided is a method for driving a non-volatile memory element in which a variable resistance element including a first electrode, a second electrode, and a variable resistance layer capable of reversibly changing between a high resistance state and a low resistance state with application of electrical signals having different polarities is connected in series with a current steering element having bidirectional rectifying characteristics with respect to an applied voltage. After the non-volatile memory element is manufactured, the resistance value of the variable resistance layer is reduced from a resistance value in the initial resistance state higher than that in the high resistance state by applying, to the non-volatile memory element, a voltage pulse having the polarity identical to that of the voltage pulse for changing the variable resistance layer from the low resistance state to the high resistance state in the normal operations. | 01-10-2013 |
20130037775 | NONVOLATILE MEMORY ELEMENT, MANUFACTURING METHOD THEREOF, AND NONVOLATILE SEMICONDUCTOR DEVICE INCORPORATING NONVOLATILE MEMORY ELEMENT - A nonvolatile memory element of the present invention comprises a first electrode ( | 02-14-2013 |
20130044534 | FORMING METHOD OF PERFORMING FORMING ON VARIABLE RESISTANCE NONVOLATILE MEMORY ELEMENT, AND VARIABLE RESISTANCE NONVOLATILE MEMORY DEVICE - A forming method of a variable resistance nonvolatile memory element capable of lowering a forming voltage and preventing variations of the forming voltage depending on variable resistance elements. The forming method is for initializing a variable resistance element, including a step (S | 02-21-2013 |
20130082230 | METHOD OF MANUFACTURING NONVOLATILE MEMORY ELEMENT, AND NONVOLATILE MEMORY ELEMENT - A variable resistance nonvolatile memory element manufacturing method includes: forming a first electrode on a substrate; forming a first metal oxide layer having a predetermined oxygen content atomic percentage on the first electrode; forming, in at least one part of the first metal oxide layer, a modified layer higher in resistance than the first metal oxide layer, by oxygen deficiency reduction; forming a second metal oxide layer lower in oxygen content atomic percentage than the first metal oxide layer, on the modified layer; and forming a second electrode on the second metal oxide layer. A variable resistance layer includes the first metal oxide layer having the modified layer and the second metal oxide layer, connects to the first electrode and the second electrode, and changes between high and low resistance states according to electrical pulse polarity. | 04-04-2013 |
20130223131 | METHOD FOR DRIVING VARIABLE RESISTANCE ELEMENT, AND NONVOLATILE MEMORY DEVICE - A driving method for driving a variable resistance element and a nonvolatile memory device, which achieves stable storage operation. In a low resistance write process, a low resistance writing voltage pulse having the negative polarity is applied once to a variable resistance layer included in a variable resistance element while in a high resistance write process, a high resistance writing voltage pulse having the positive polarity is applied more than twice to the same variable resistance layer. Here, when a voltage value of one of the high resistance writing voltage pulses is VH | 08-29-2013 |
20130242642 | VARIABLE RESISTANCE NONVOLATILE MEMORY ELEMENT WRITING METHOD - A variable resistance nonvolatile memory element writing method according to the present disclosure includes: (a) changing a variable resistance layer to a low resistance state by applying, to a second electrode, a first voltage which is negative with respect to a first electrode; and (b) changing the variable resistance layer to a high resistance state. Step (b) includes: (i) applying, to the second electrode, a second voltage which is positive with respect to the first electrode; and (ii) changing the variable resistance layer to the high resistance state by applying, to the second electrode, a third voltage, which is negative with respect to the first electrode and is smaller than the absolute value of a threshold voltage for changing the variable resistance layer from the high resistance state to the low resistance state, after the positive second voltage is applied in step (i). | 09-19-2013 |
20130250658 | NONVOLATILE MEMORY ELEMENT AND NONVOLATILE MEMORY DEVICE - A nonvolatile memory device includes: a first electrode; a second electrode; and a variable resistance layer which includes: a first oxide layer including a first metal oxide; a second oxide layer located between and in contact with the first oxide layer and a second electrode including a second metal oxide and having a degree of oxygen deficiency lower than a degree of oxygen deficiency of the first oxide layer; and a local region located in the first oxide layer and the second oxide layer, having contact with the second electrode and no contact with the first electrode, and having a degree of oxygen deficiency higher than the degree of oxygen deficiency of the second oxide layer and different from the degree of oxygen deficiency of the first oxide layer. | 09-26-2013 |
20130314975 | METHOD FOR PROGRAMMING NONVOLATILE MEMORY ELEMENT, METHOD FOR INITIALIZING NONVOLATILE MEMORY ELEMENT, AND NONVOLATILE MEMORY DEVICE - A method for programming a nonvolatile memory element includes: decreasing a resistance value of a variable resistance element in an initial state, by applying an initialization voltage pulse to a series circuit in which a load resistor having a first resistance value is connected in series with the variable resistance element and a MSM diode; applying, after the decreasing, a write voltage pulse to the series circuit after the resistance value of the variable resistance element is changed to a second resistance value lower than the first resistance value; and applying, after the decreasing, an erase voltage pulse to the series circuit after the resistance value of the variable resistance element is changed to a third resistance value lower than the first resistance value. | 11-28-2013 |
20140050014 | DRIVING METHOD OF VARIABLE RESISTANCE ELEMENT AND NON-VOLATILE MEMORY DEVICE - A method of driving a variable resistance element comprises: before a first write step is performed, applying an initial voltage pulse of a first polarity to change a resistance value of a metal oxide layer from a resistance value corresponding to an initial state of the metal oxide layer to another resistance value; wherein when the resistance value corresponding to the initial state is R0, the resistance value corresponding to a write state is RL, the resistance value corresponding to an erase state is RH, another resistance value is R2, a maximum value of the current flowing when the initial voltage pulse is applied is IbRL, a maximum value of the current flowing when the write voltage pulse is applied is IRL, and a maximum value of the current flowing when the erase voltage pulse is applied is IRH, R0>RH>R2≧RL, and |IRL|>|IbRL| are satisfied. | 02-20-2014 |
20140061579 | NONVOLATILE MEMORY ELEMENT AND NONVOLATILE MEMORY DEVICE - A variable resistance nonvolatile memory element includes a first electrode, a second electrode, and a variable resistance layer including: a first oxide layer including a metal oxide having non-stoichiometric composition and including p-type carriers; a second oxide layer located between and in contact with the first oxide layer and a second electrode and including a metal oxide having non-stoichiometric composition and including n-type carriers; an oxygen reservoir region located in the first oxide layer, having no contact with the first electrode, and having an oxygen content atomic percentage higher than that of the first oxide layer; and a local region located in the second oxide layer, having contact with the oxygen reservoir region, and having an oxygen content atomic percentage lower than that of the second oxide layer. | 03-06-2014 |
20140126267 | VARIABLE RESISTANCE NONVOLATILE MEMORY DEVICE - Provided is a variable resistance element (Rij) the resistance state of which is reversibly changed by applying electrical signals of different polarities; and a current steering element (Dij) in which a first current is larger than a second current, the first current being a current which flows when a voltage of the first polarity having a first value is applied, the first value being less than a predetermined voltage value and having an absolute value greater than zero, the second current being a current which flows when a voltage of the second polarity having an absolute value which is the first value is applied, the second polarity being different from the first polarity, in which Rij and Dij are connected in series such that the polarity of a voltage to be applied to Dij is the second polarity when the resistance state of Rij is changed to high resistance state. | 05-08-2014 |
20140126268 | METHOD OF DRIVING NONVOLATILE MEMORY ELEMENT AND NONVOLATILE MEMORY DEVICE - A method of driving a nonvolatile memory element including a variable resistance element having a state reversibly changing between low and high resistance states by an applied electrical signal and a transistor serially connected to the variable resistance element. The method including: setting the variable resistance element to the low resistance state by applying a first gate voltage to a gate of the transistor and applying a first write voltage negative with respect to a first electrode; and changing a resistance value of the transistor obtained in a low-resistance write operation, when a value of current passing through the variable resistance element in the setting of the low resistance state or a resistance value of the nonvolatile memory element in the case where the variable resistance element is in the low resistance state is outside a predetermined range. | 05-08-2014 |
20140203234 | VARIABLE RESISTANCE NONVOLATILE MEMORY ELEMENT AND METHOD OF MANUFACTURING THE SAME - A variable resistance nonvolatile memory element includes: first and second electrode layers; a first variable resistance layer between the first and second electrode layers; and a second variable resistance layer between the second electrode layer and the first variable resistance layer and having a higher resistance value than the first variable resistance layer. When viewed in a direction perpendicular to the major surface of the second variable resistance layer, an outline of the second variable resistance layer is located inwardly of the outline of any one of the second electrode layer and the first variable resistance layer, and an outline of a face of the second variable resistance layer, the face being in contact with the first variable resistance layer is located inwardly of an outline of a face of the first variable resistance layer, the face being in contact with the second variable resistance layer. | 07-24-2014 |
20140321197 | DRIVING METHOD OF NON-VOLATILE MEMORY ELEMENT AND NON-VOLATILE MEMORY DEVICE - In a driving method of a non-volatile memory element, the polarity of a write voltage pulse applied to change a variable resistance layer from a high-resistance state to a low-resistance state is such that an input/output terminal which is more distant from the variable resistance element becomes a source terminal, and when a first write voltage pulse is applied to change the variable resistance layer in the high-resistance state to the low-resistance state, a first gate voltage is applied to a gate terminal, while when a second write voltage pulse which is greater in absolute value of voltage than the first write voltage pulse is applied to change the variable resistance layer in an excess-resistance state to the low-resistance state, a second gate voltage which is smaller in absolute value than the first gate voltage is applied to the gate terminal. | 10-30-2014 |