Patents by Inventor Shi-Jung Kim
Shi-Jung Kim has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 10164173Abstract: Magnetic random access memory (MRAM) devices, and methods of manufacturing the same, include at least one first magnetic material pattern on a substrate, at least one second magnetic material pattern on the at least one first magnetic material pattern, and at least one tunnel barrier layer pattern between the at least one first magnetic material pattern and the at least one second magnetic material pattern. A width of a top surface of the at least one first magnetic material pattern may be less than a width of a bottom surface of the at least one second magnetic material pattern.Type: GrantFiled: July 25, 2017Date of Patent: December 25, 2018Assignee: Samsung Electronics Co., Ltd.Inventors: Kyu-Man Hwang, Shi-Jung Kim, Mi-Lim Park, Jun-Soo Bae, Seung-Woo Lee
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Patent number: 10147451Abstract: A data storage device may have increased signal-to-noise ratio contact detection by employing a transducing head assembly separated from a data storage medium by an air bearing with the transducing head assembly receiving an alternating current as directed from a controller. The alternating current can be configured to induce random transducing head motion when the air bearing has a greater than zero size and a cyclical transducing head motion when the air bearing has a zero size.Type: GrantFiled: September 11, 2017Date of Patent: December 4, 2018Assignee: Seagate Technology LLCInventors: Shi Jung Kim, Ju Yong Lee, YoungJin Son
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Publication number: 20180174614Abstract: A data storage device may have increased signal-to-noise ratio contact detection by employing a transducing head associated with a data storage medium each connected to a controller. The transducing head can have an alternating current heater excited to a first frequency for a first revolution of the data storage medium and to a different second frequency for a second revolution of the data storage medium. The second frequency may produce lateral transducing head motion as a result of physical contact of the transducing head with the data storage medium. The controller can issue a contact status in response to comparing a first plurality of position error signals logged during the first frequency to a second plurality of position error signals logged during the second frequency.Type: ApplicationFiled: September 11, 2017Publication date: June 21, 2018Inventors: Shi Jung Kim, Ju Yong Lee, YoungJin Son
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Publication number: 20170324031Abstract: Magnetic random access memory (MRAM) devices, and methods of manufacturing the same, include at least one first magnetic material pattern on a substrate, at least one second magnetic material pattern on the at least one first magnetic material pattern, and at least one tunnel barrier layer pattern between the at least one first magnetic material pattern and the at least one second magnetic material pattern. A width of a top surface of the at least one first magnetic material pattern may be less than a width of a bottom surface of the at least one second magnetic material pattern.Type: ApplicationFiled: July 25, 2017Publication date: November 9, 2017Applicant: Samsung Electronics Co., Ltd.Inventors: Kyu-Man HWANG, Shi-Jung KIM, Mi-Lim PARK, Jun-Soo BAE, Seung-Woo LEE
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Patent number: 9761792Abstract: Magnetic random access memory (MRAM) devices, and methods of manufacturing the same, include at least one first magnetic material pattern on a substrate, at least one second magnetic material pattern on the at least one first magnetic material pattern, and at least one tunnel barrier layer pattern between the at least one first magnetic material pattern and the at least one second magnetic material pattern. A width of a top surface of the at least one first magnetic material pattern may be less than a width of a bottom surface of the at least one second magnetic material pattern.Type: GrantFiled: October 20, 2015Date of Patent: September 12, 2017Assignee: Samsung Electronics Co., Ltd.Inventors: Kyu-Man Hwang, Shi-Jung Kim, Mi-Lim Park, Jun-Soo Bae, Seung-Woo Lee
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Patent number: 9761270Abstract: A data storage device may have increased signal-to-noise ratio contact detection by employing a transducing head associated with a data storage medium each connected to a controller. The transducing head can have an alternating current heater excited to a first frequency for a first revolution of the data storage medium and to a different second frequency for a second revolution of the data storage medium. The second frequency may produce lateral transducing head motion as a result of physical contact of the transducing head with the data storage medium. The controller can issue a contact status in response to comparing a first plurality of position error signals logged during the first frequency to a second plurality of position error signals logged during the second frequency.Type: GrantFiled: December 21, 2016Date of Patent: September 12, 2017Assignee: Seagate Technology LLCInventors: Shi Jung Kim, Ju Yong Lee, YoungJin Son
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Patent number: 9607642Abstract: An AC signal having a specified frequency and a DC offset voltage is applied to a slider substrate or a magnetic recording medium. A low- or non-modulation interface is defined between the slider and medium. In response to applying the AC signal, an oscillation in an electrostatic force occurs between the slider and the medium at the specified frequency, which causes an oscillation in thermal sensor signal at the slider, which oscillates at the specified frequency. A heater of the slider is adjusted to decrease spacing between the slider and medium during oscillation of the electrostatic force. For each heater adjustment, thermal sensor resistance is measured over a specified number of medium revolutions. Head-medium contact is detected using one of an amplitude of a harmonic of the thermal sensor signal and a summation of amplitudes of all frequency components at the specified frequency.Type: GrantFiled: January 27, 2016Date of Patent: March 28, 2017Assignee: SEAGATE TECHNOLOGY LLCInventors: Won Choul Yang, Jin Pil Kim, Shi Jung Kim
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Publication number: 20160307590Abstract: A current temperature of a data storage device having a heat assisted recording (HAMR) device is measured while in idle. A threshold laser diode power output of the HAMR device is calculated at the current temperature when there is a change between a previous temperature and the current temperature. A new laser diode current that produced the calculated threshold laser diode power output is applied to the HAMR device when there is a change between the currently applied laser diode current and the new laser diode current.Type: ApplicationFiled: April 16, 2015Publication date: October 20, 2016Inventors: Won Choul Yang, Shi Jung Kim, Ju Yong Lee
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Patent number: 9472229Abstract: A current temperature of a data storage device having a heat assisted recording (HAMR) device is measured while in idle. A threshold laser diode power output of the HAMR device is calculated at the current temperature when there is a change between a previous temperature and the current temperature. A new laser diode current that produced the calculated threshold laser diode power output is applied to the HAMR device when there is a change between the currently applied laser diode current and the new laser diode current.Type: GrantFiled: April 16, 2015Date of Patent: October 18, 2016Assignee: Seagate Technology LLCInventors: Won Choul Yang, Shi Jung Kim, Ju Yong Lee
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Patent number: 9437234Abstract: An apparatus comprises a read/write head having a heater, wherein a low- or non-modulation interface is defined between the head and a magnetic recording medium. A microactuator is coupled to the head. A main actuator is coupled to the microactuator and the head. A controller is coupled to the main actuator, the microactuator, and the head. The controller is configured to control movement of the main actuator and the microactuator in response to a position error signal. The controller is further configured to induce an oscillation in the heater at a predetermined frequency. A detector is coupled to the controller. The detector is configured to sense a disturbance in the PES supplied to the microactuator resulting from the induced heater oscillation, and detect contact between the head and the medium using the PES disturbance.Type: GrantFiled: August 20, 2015Date of Patent: September 6, 2016Assignee: SEAGATE TECHNOLOGY LLCInventors: Shi Jung Kim, Dong Wook Lee, Ju Yong Lee, Won Choul Yang
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Publication number: 20160155934Abstract: Magnetic random access memory (MRAM) devices, and methods of manufacturing the same, include at least one first magnetic material pattern on a substrate, at least one second magnetic material pattern on the at least one first magnetic material pattern, and at least one tunnel barrier layer pattern between the at least one first magnetic material pattern and the at least one second magnetic material pattern. A width of a top surface of the at least one first magnetic material pattern may be less than a width of a bottom surface of the at least one second magnetic material pattern.Type: ApplicationFiled: October 20, 2015Publication date: June 2, 2016Inventors: Kyu-Man HWANG, Shi-Jung KIM, Mi-Lim PARK, Jun-Soo BAE, Seung-Woo LEE
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Patent number: 9245561Abstract: An apparatus comprises a slider that includes a fly height sensor. A signal generator is coupled to the slider. The signal generator is configured to generate an AC electrical signal having a DC offset voltage and to adjust the DC offset of the AC electrical signal to a plurality of DC offset voltages. Circuitry is coupled to the fly height sensor and the signal generator. The circuitry is configured to measure fly height of the slider in response to application of the AC electrical signal with varying DC offset voltages to the slider. The circuitry is further configured to determine an extremum of the measured fly heights and generate an output that includes the DC offset voltage associated with the fly height extremum.Type: GrantFiled: March 24, 2015Date of Patent: January 26, 2016Assignee: SEAGATE TECHNOLOGY LLCInventors: Ju Yong Lee, Won Choul Yang, Shi Jung Kim
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Patent number: 9195533Abstract: The disclosure is related to an apparatus and methods for addressing variations in bit error rates amongst data storage segments. In a particular embodiment, an apparatus includes a controller that detects variations in bit error rates amongst different segments of a plurality of segments in a storage medium. The controller also adjusts a read/write operation parameter according to the detected variations amongst the bit error rates in the plurality of segments.Type: GrantFiled: September 27, 2013Date of Patent: November 24, 2015Assignee: Seagate Technology LLCInventors: Won Choul Yang, Shi Jung Kim, Ju Yong Lee, Clifford Jayson Bringas Camalig, Mui Chong Chai
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Patent number: 8934188Abstract: Technologies are described herein for adaptive write pole tip protrusion compensation in a storage device having magnetic recording media. Variations in temperature of a head of a storage device are measured for various combinations of values of write-channel parameters during multiple test writes to the recording media. Sensitivity of the head temperature to change in value of the write-channel parameters is determined from the temperature measurements. A ratio of change in write pole tip protrusion of the head to change in head temperature is also determined. From the sensitivity of the head temperature to change in value of the write-channel parameters and the ratio of change in write pole tip protrusion of the head to change in head temperature, a coefficient corresponding to each write-channel parameter is calculated for the head to be utilized in a write pole tip protrusion compensation mechanism of the storage device.Type: GrantFiled: September 25, 2013Date of Patent: January 13, 2015Assignee: Seagate Technology LLCInventors: Shi Jung Kim, Won Choul Yang, Ju Yong Lee
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Publication number: 20100246072Abstract: A hard disk drive having an actuator coupled to a pivot part about which the actuator rotates, including first and second pivot bearings coupled to the actuator and the pivot part, wherein a rotation center of at least one of the first and second pivot bearings is offset from respective longitudinal centers of the first and second pivot bearings.Type: ApplicationFiled: March 31, 2010Publication date: September 30, 2010Applicant: Samsung Electronics Co., LtdInventor: Shi-Jung Kim
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Publication number: 20090268342Abstract: A disk clamp to fix a disk to a hub of a spindle motor in a hard disk drive, and a hard disk drive having the disk clamp. The disk clamp can include a coupling hole formed at a center of the disk clamp, in which a clamping screw is inserted, at least one through hole formed outside the coupling hole, and a pressing portion provided at an outer circumferential side of the disk clamp to contact and press the disk. A particular area around the at least one through hole that is away from the at least one through hole can have a sectional thickness thinner than a predetermined area that is adjacent to the at least one through hole, to prevent stress distribution generated at a contact surface between the pressing portion and the disk from being irregular due to the at least one through hole.Type: ApplicationFiled: April 23, 2009Publication date: October 29, 2009Applicant: Samsung Electronics Co., Ltd.Inventors: Woo Chul KIM, Woo Sung Kim, Shi-Jung Kim, Yoou Gyu Kam
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Publication number: 20070133124Abstract: A disk clamp to affix a disk of a hard disk drive to a spindle motor. The disk clamp includes a coupling part coupled to an upper portion of the spindle motor with screws, a pressing part provided outside the coupling part to press the disk against the spindle motor, and an elastic deformation part provided between the coupling part and the pressing part and adapted to be flexed in an elastically restorable manner, when the screws are tightened, to impart a pressing force to the pressing part. A hard disk drive including the disk clamp is also provided.Type: ApplicationFiled: December 7, 2006Publication date: June 14, 2007Applicant: Samsung Electronics Co., Ltd.Inventors: Youn-tai Kim, Back-ho Heo, Shi-jung Kim, Sung-wook Kang