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Chang Wook Jeong, Seoul KR

Chang Wook Jeong, Seoul KR

Patent application numberDescriptionPublished
20080266942Multiple level cell phase-change memory device having pre-reading operation resistance drift recovery, memory systems employing such devices and methods of reading memory devices - A memory device comprises a plurality of memory cells, each memory cell comprising a memory cell material that has an initial resistance that is determined in response to an applied programming current in a programming operation, the resistance of the memory cell varying from the initial resistance over a time period following the programming operation, and each memory cell being connected to a conduction line of the memory device that is used to apply the programming current to program the resistance of the corresponding memory cell in the programming operation and that is used to apply a read current to read the resistance of the corresponding memory cell in a read operation. A modification circuit modifies the resistance of a memory cell of the plurality of memory cells selected for a read operation to return its resistance to near the initial resistance prior to a read operation of the memory cell.10-30-2008
20080283813Semiconductor memory device and method of manufacturing the same - A semiconductor memory device includes first conductive lines on a substrate, an interlayer insulating layer with a plurality of via holes on the substrate, second conductive lines on the interlayer insulating layer, and a resistive memory material in the via holes and electrically connected to the first and second conductive lines, the resistive memory material having a vertically non-uniform specific resistance profile with respect to the substrate.11-20-2008
20080316804Multiple level cell phase-change memory devices having controlled resistance drift parameter, memory systems employing such devices and methods of reading memory devices - In a method of controlling resistance drift in a memory cell of a resistance-changeable material memory device, the resistance changeable material in the memory cell is treated so that a drift parameter for the memory cell is less than about 0.18, wherein a change in resistance of a memory cell over the time period is determined according to the relationship:12-25-2008
20090016099Multiple level cell phase-change memory devices having post-programming operation resistance drift saturation, memory systems employing such devices and methods of reading memory devices - In a memory device and in a method of programming the same, a memory device comprises: a plurality of memory cells, each memory cell comprising a resistance-changeable material that has an initial resistance that is determined in response to an applied programming current in a programming operation; and a modification circuit that modifies the resistance of the memory cell following a programming operation of the memory cell to vary the resistance of the memory cell from the initial resistance to a second resistance by applying a saturation current in a saturation operation. Each memory cell is connected to a conduction line of the memory device that is used to apply the programming current to program the resistance of the corresponding memory cell in the programming operation, that is used to apply the saturation current to the corresponding memory cell in the saturation operation and that is used to apply a read current to read the resistance of the corresponding memory cell in a subsequent read operation.01-15-2009
20090101881SEMICONDUCTOR DEVICES HAVING PHASE CHANGE MEMORY CELLS, ELECTRONIC SYSTEMS EMPLOYING THE SAME AND METHODS OF FABRICATING THE SAME - In one embodiment, a phase-change memory device has an oxidation barrier layer to protect against memory cell contamination or oxidation and a method of manufacturing the same. In one embodiment, a semiconductor memory device comprises a molding layer overlying a semiconductor substrate. The molding layer has a protrusion portion vertically extending from a top surface thereof. The device further includes a phase-changeable material pattern adjacent the protrusion portion and a lower electrode electrically connected to the phase-changeable material pattern.04-23-2009
20100015785Method for reducing a reset current for resetting a portion of a phase change material in a memory cell of a phase change memory device and the phase change memory device - According to one embodiment, at least a portion of the phase change material including a first crystalline phase is converted to one of a second crystalline phase and an amorphous phase. The second crystalline phase transitions to the amorphous phase more easily than the first crystalline phase. For example, the first crystalline phase may be a hexagonal closed packed structure, and the first crystalline phase may be a face centered cubic structure.01-21-2010
20100090194MULTI-BIT PHASE-CHANGE RANDOM ACCESS MEMORY (PRAM) WITH DIAMETER-CONTROLLED CONTACTS AND METHODS OF FABRICATING AND PROGRAMMING THE SAME - A phase-change random-access memory (PRAM) device includes a chalcogenide element, the chalcogenide element comprising a material which can assume a crystalline state or an amorphous state upon application of a heating current. A first contact is connected to a first region of the chalcogenide element and has a first cross-sectional area. A second contact is connected to a second region of the chalcogenide element and having a second cross-sectional area. A first programmable volume of the chalcogenide material is defined in the first region of the chalcogenide element, a state of the first programmable volume being programmable according to a resistance associated with the first contact. A second programmable volume of the chalcogenide material is defined in the second region of the chalcogenide element, a state of the second programmable volume being programmable according to a second resistance associated with the second contact.04-15-2010
20100090213ONE-TIME PROGRAMMABLE DEVICES INCLUDING CHALCOGENIDE MATERIAL AND ELECTRONIC SYSTEMS INCLUDING THE SAME - A method of programming a one-time programmable device is provided. A switching device disposed in a substrate is turned on and a program current is applied to a fuse electrically connected to the switching device, thereby cutting the fuse. The fuse includes a first electrode electrically connected to the switching device, a second electrode spaced apart from the first electrode, and a chalcogenide pattern disposed between the first and second electrodes. Related one-time programmable devices, phase change memory devices and electronic systems are also disclosed.04-15-2010
20110106145TOOL FOR MINIMALLY INVASIVE SURGERY - The present invention relates to an easy-to-control tool for minimally invasive surgery. In accordance with an aspect of the present invention, there is provided a tool for minimally invasive surgery comprising, an elongated shaft having a predetermined length, an adjustment handle manually controllable by a user, a first pitch axis part and a first yaw axis part positioned around one end of the elongated shaft for transferring motions in pitch and yaw directions following the operation of the adjustment handle, a second pitch axis part and a second yaw axis part positioned around the other end of the elongated shaft for operating corresponding to the operations from the first pitch axis part and the first yaw axis part, respectively, and an end effector controllable by the second pitch axis part and the second yaw axis part, wherein the first pitch axis part drives the second pitch axis part by at least one pitch axis actuating cable, and the first yaw axis part drives the second yaw axis part by at least one yaw axis actuating cable.05-05-2011
20110106146TOOL FOR MINIMALLY INVASIVE SURGERY - The present invention relates to an easy-to-control tool for minimally invasive surgery. In accordance with an aspect of the present invention, there is provided a tool for minimally invasive surgery comprising, an elongated shaft having a predetermined length, an adjustment handle manually controllable by a user, a pitch direction handling part and a yaw direction handling part positioned around one end of the elongated shaft for transferring motions in pitch and yaw directions following the actuation of the adjustment handle, a pitch direction actuating part and a yaw direction actuating part positioned around the other end of the elongated shaft for operating corresponding to the operations from the pitch direction handling part and the yaw direction handling part, respectively, an end effector controllable by the pitch direction actuating part and the yaw direction actuating part, and a plurality of cables for transferring the from the pitch direction handling part and the yaw direction handling part to the pitch direction actuating part and the yaw direction actuating part, respectively.05-05-2011
20110152922TOOL FOR MINIMALLY INVASIVE SURGERY AND METHOD FOR USING THE SAME - The present invention relates to an easy-to-control tool for minimally invasive surgery and a method for using the same. In accordance with an aspect of the present invention, there is provided a tool for minimally invasive surgery and a method for using the same comprising, a main shaft, a first control shaft and a second control shaft positioned in sequence from one end of the main shaft, a first actuating shaft and a second actuating shaft positioned in sequence from the other end of the main shaft, an adjustment handle positioned around one end of the second control shaft, an end effector positioned around one end of the second actuating shaft, a pitch control part positioned around one position of the positions between the main shaft and the first control shaft, between the first control shaft and the second control shaft, and between the second control shaft and the adjustment handle, for transferring a motion of the adjustment handle in a pitch direction to the end effector, a first yaw control part and a second yaw control part positioned around the other positions of the positions between the main shaft and the first control shaft, between the first control shaft and the second control shaft, and between the second control shaft and the adjustment handle, respectively, for transferring a motion of the adjustment handle in a yaw direction to the end effector, a pitch actuating part positioned around one position of the positions between the main shaft and the first actuating shaft, between the first actuating shaft and the second actuating shaft, and between the second actuating shaft and the end effector, a first yaw actuating part and a second yaw actuating part positioned around the other positions of the positions between the main shaft and the first actuating shaft, between the first actuating shaft and the second actuating shaft, and between the second actuating shaft and the end effector, respectively, and a pitch cable, a first yaw cable, and a second yaw cable for transferring motions from the pitch control part, the first yaw control part, and the second yaw control part to the pitch actuating part, the first yaw actuating part, and the second yaw actuating part.06-23-2011

Patent applications by Chang Wook Jeong, Seoul KR