Patents by Inventor Zhijian J. Yang

Zhijian J. Yang 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).

  • Patent number: 9166588
    Abstract: A Physical Unclonable Function (PUF) semiconductor device includes a semiconductor substrate, and a well formed in the semiconductor substrate. The well includes a first region having a first concentration of ions, and at least one second region having a second concentration that is less than the first concentration. First and second FETs are formed on the well. The first and second FETs have a voltage threshold mismatch with respect to one another based on the first region and the at least one second region.
    Type: Grant
    Filed: January 20, 2014
    Date of Patent: October 20, 2015
    Assignee: GLOBALFOUNDIRES INC.
    Inventors: Kai D. Feng, Wai-Kin Li, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20150207505
    Abstract: A Physical Unclonable Function (PUF) semiconductor device includes a semiconductor substrate, and a well formed in the semiconductor substrate. The well includes a first region having a first concentration of ions, and at least one second region having a second concentration that is less than the first concentration. First and second FETs are formed on the well. The first and second FETs have a voltage threshold mismatch with respect to one another based on the first region and the at least one second region.
    Type: Application
    Filed: January 20, 2014
    Publication date: July 23, 2015
    Applicant: International Business Machines Corporation
    Inventors: Kai D. Feng, Wai-Kin Li, Ping-Chuan Wang, Zhijian J. Yang
  • Patent number: 8759175
    Abstract: A flash memory structure having an enhanced capacitive coupling coefficient ratio (CCCR) may be fabricated in a self-aligned manner while using a semiconductor substrate that has an active region that is recessed within an aperture with respect to an isolation region that surrounds the active region. The flash memory structure includes a floating gate that does not rise above the isolation region, and that preferably consists of a single layer that has a U shape. The U shape facilitates the enhanced capacitive coupling coefficient ratio.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: June 24, 2014
    Assignee: International Business Machines Corporation
    Inventors: Louis C. Hsu, Xu Ouyang, Ping-Chuan Wang, Zhijian J. Yang
  • Patent number: 8687445
    Abstract: A method for repairing degraded field effect transistors includes forward biasing PN junctions of one of a source and a drain of a field effect transistor (FET), and a body of the FET. Charge is injected from a substrate to a gate region to neutralize charge in the gate region. The method is applicable to CMOS devices. Repair circuits are disclosed for implementing the repairs.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: April 1, 2014
    Assignee: International Business Machines Corporation
    Inventors: Louis L. C. Hsu, Rajiv V. Joshi, Zhijian J. Yang, Ping-Chuan Wang
  • Patent number: 8422322
    Abstract: A method for repairing degraded field effect transistors includes forward biasing PN junctions of one of a source and a drain of a field effect transistor (FET), and a body of the FET. Charge is injected from a substrate to a gate region to neutralize charge in the gate region. The method is applicable to CMOS devices. Repair circuits are disclosed for implementing the repairs.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: April 16, 2013
    Assignee: International Business Machines Corporation
    Inventors: Louis L. C. Hsu, Rajiv V. Joshi, Zhijian J. Yang, Ping-Chuan Wang
  • Publication number: 20120184076
    Abstract: A flash memory structure having an enhanced capacitive coupling coefficient ratio (CCCR) may be fabricated in a self-aligned manner while using a semiconductor substrate that has an active region that is recessed within an aperture with respect to an isolation region that surrounds the active region. The flash memory structure includes a floating gate that does not rise above the isolation region, and that preferably consists of a single layer that has a U shape. The U shape facilitates the enhanced capacitive coupling coefficient ratio.
    Type: Application
    Filed: March 26, 2012
    Publication date: July 19, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Louis C. Hsu, Xu Ouyang, Ping-Chuan Wang, Zhijian J. Yang
  • Patent number: 8193575
    Abstract: A flash memory structure having an enhanced capacitive coupling coefficient ratio (CCCR) may be fabricated in a self-aligned manner while using a semiconductor substrate that has an active region that is recessed within an aperture with respect to an isolation region that surrounds the active region. The flash memory structure includes a floating gate that does not rise above the isolation region, and that preferably consists of a single layer that has a U shape. The U shape facilitates the enhanced capacitive coupling coefficient ratio.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: June 5, 2012
    Assignee: International Business Machines Corporation
    Inventors: Louis C. Hsu, Xu Ouyang, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20120051166
    Abstract: A method for repairing degraded field effect transistors includes forward biasing PN junctions of one of a source and a drain of a field effect transistor (FET), and a body of the FET. Charge is injected from a substrate to a gate region to neutralize charge in the gate region. The method is applicable to CMOS devices. Repair circuits are disclosed for implementing the repairs.
    Type: Application
    Filed: November 3, 2011
    Publication date: March 1, 2012
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Louis L. C. Hsu, Rajiv V. Joshi, Zhijian J. Yang, Ping-Chuan Wang
  • Patent number: 8098536
    Abstract: A method for repairing degraded field effect transistors includes forward biasing PN junctions of one of a source and a drain of a field effect transistor (FET), and a body of the FET. Charge is injected from a substrate to a gate region to neutralize charge in the gate region. The method is applicable to CMOS devices. Repair circuits are disclosed for implementing the repairs.
    Type: Grant
    Filed: January 24, 2008
    Date of Patent: January 17, 2012
    Assignee: International Business Machines Corporation
    Inventors: Louis L. C. Hsu, Rajiv V. Joshi, Zhijian J. Yang, Ping-Chuan Wang
  • Patent number: 7904273
    Abstract: A system, method and device for measuring a depth of a Through-Silicon-Via (TSV) in a semiconductor device region on a wafer during in-line semiconductor fabrication, includes a resistance measurement trench structure having length and width dimensions in a substrate, ohmic contacts on a surface of the substrate disposed on opposite sides of the resistance measurement trench structure, and an unfilled TSV structure in semiconductor device region having an unknown depth. A testing circuit makes contact with the ohmic contacts and measures a resistance therebetween, and a processor connected to the testing circuit calculates a depth of the trench structure and the unfilled TSV structure based on the resistance measurement. The resistance measurement trench structure and the unfilled TSV are created simultaneously during fabrication.
    Type: Grant
    Filed: February 16, 2009
    Date of Patent: March 8, 2011
    Assignee: International Business Machines Corporation
    Inventors: Qizhi Liu, Ping-Chuan Wang, Kimball M. Watson, Zhijian J. Yang
  • Publication number: 20100210043
    Abstract: A system, method and device for measuring a depth of a Through-Silicon-Via (TSV) in a semiconductor device region on a wafer during in-line semiconductor fabrication, includes a resistance measurement trench structure having length and width dimensions in a substrate, ohmic contacts on a surface of the substrate disposed on opposite sides of the resistance measurement trench structure, and an unfilled TSV structure in semiconductor device region having an unknown depth. A testing circuit makes contact with the ohmic contacts and measures a resistance therebetween, and a processor connected to the testing circuit calculates a depth of the trench structure and the unfilled TSV structure based on the resistance measurement. The resistance measurement trench structure and the unfilled TSV are created simultaneously during fabrication.
    Type: Application
    Filed: February 16, 2009
    Publication date: August 19, 2010
    Applicant: International Business Machines Corporation
    Inventors: Qizhi Liu, Ping-Chuan Wang, Kimball M. Watson, Zhijian J. Yang
  • Patent number: 7723824
    Abstract: A method for recovery of degradation caused by avalanche hot carriers is provided that includes subjecting an idle bipolar transistor exhibiting avalanche degradation to a thermal anneal step which increases temperature of the transistor thereby recovering the avalanche degradation of the bipolar transistor. In one embodiment, the annealing source is a self-heating structure that is a Si-containing resistor that is located side by side with an emitter of the bipolar transistor. During the recovering step, the bipolar transistor including the self-heating structure is placed in the idle mode (i.e., without bias) and a current from a separate circuit is flown through the self-heating structure. In another embodiment of the present, the annealing step is a result of providing a high forward current (around the peak fT current or greater) to the bipolar transistor while operating below the avalanche condition (VCB of less than 1 V).
    Type: Grant
    Filed: May 4, 2007
    Date of Patent: May 25, 2010
    Assignee: International Business Machines Corporation
    Inventors: Fernando Guarin, J. Edwin Hostetter, Jr., Stewart E. Rauch, III, Ping-Chuan Wang, Zhijian J. Yang
  • Patent number: 7675378
    Abstract: Disclosed are embodiments of a voltage controlled oscillator (VCO) capable of non-volatile self-correction to compensate for process variations and to ensure that the center frequency of the oscillator is maintained within a predetermined frequency range. This VCO incorporates a pair of varactors connected in parallel to an inductor-capacitor (LC) tank circuit for outputting a periodic signal having a frequency that is proportional to an input voltage. A control loop uses a programmable variable resistance e-fuse to set a compensation voltage to be applied to the pair of varactors. By adjusting the compensation voltage, the capacitance of the pair of varactors can be adjusted in order to selectively increase or decrease the frequency of the periodic signal in response to a set input voltage and, thereby to bring the frequency of that periodic signal into the predetermined frequency range.
    Type: Grant
    Filed: May 2, 2008
    Date of Patent: March 9, 2010
    Assignee: International Business Machines Corporation
    Inventors: Kai D. Feng, Kafai Lai, Ping-Chuan Wang, Zhijian J. Yang
  • Patent number: 7609121
    Abstract: Disclosed are embodiments of a voltage controlled oscillator (VCO) capable of non-volatile self-correction to compensate for process variations and to ensure that the center frequency of the oscillator is maintained within a predetermined frequency range. This VCO incorporates a pair of varactors connected in parallel to an inductor-capacitor (LC) tank circuit for outputting a periodic signal having a frequency that is proportional to an input voltage. A control loop uses a programmable variable resistance e-fuse to set a compensation voltage to be applied to the pair of varactors. By adjusting the compensation voltage, the capacitance of the pair of varactors can be adjusted in order to selectively increase or decrease the frequency of the periodic signal in response to a set input voltage and, thereby to bring the frequency of that periodic signal into the predetermined frequency range.
    Type: Grant
    Filed: March 28, 2008
    Date of Patent: October 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: Kai D. Feng, Kafai Lai, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20090243739
    Abstract: Disclosed are embodiments of a voltage controlled oscillator (VCO) capable of non-volatile self-correction to compensate for process variations and to ensure that the center frequency of the oscillator is maintained within a predetermined frequency range. This VCO incorporates a pair of varactors connected in parallel to an inductor-capacitor (LC) tank circuit for outputting a periodic signal having a frequency that is proportional to an input voltage. A control loop uses a programmable variable resistance e-fuse to set a compensation voltage to be applied to the pair of varactors. By adjusting the compensation voltage, the capacitance of the pair of varactors can be adjusted in order to selectively increase or decrease the frequency of the periodic signal in response to a set input voltage and, thereby to bring the frequency of that periodic signal into the predetermined frequency range.
    Type: Application
    Filed: May 2, 2008
    Publication date: October 1, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kai D. Feng, Kafai Lai, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20090243738
    Abstract: Disclosed are embodiments of a voltage controlled oscillator (VCO) capable of non-volatile self-correction to compensate for process variations and to ensure that the center frequency of the oscillator is maintained within a predetermined frequency range. This VCO incorporates a pair of varactors connected in parallel to an inductor-capacitor (LC) tank circuit for outputting a periodic signal having a frequency that is proportional to an input voltage. A control loop uses a programmable variable resistance e-fuse to set a compensation voltage to be applied to the pair of varactors. By adjusting the compensation voltage, the capacitance of the pair of varactors can be adjusted in order to selectively increase or decrease the frequency of the periodic signal in response to a set input voltage and, thereby to bring the frequency of that periodic signal into the predetermined frequency range.
    Type: Application
    Filed: March 28, 2008
    Publication date: October 1, 2009
    Inventors: Kai D. Feng, Kafai Lai, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20090200598
    Abstract: A flash memory structure having an enhanced capacitive coupling coefficient ratio (CCCR) may be fabricated in a self-aligned manner while using a semiconductor substrate that has an active region that is recessed within an aperture with respect to an isolation region that surrounds the active region. The flash memory structure includes a floating gate that does not rise above the isolation region, and that preferably consists of a single layer that has a U shape. The U shape facilitates the enhanced capacitive coupling coefficient ratio.
    Type: Application
    Filed: February 7, 2008
    Publication date: August 13, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Louis C. Hsu, Xu Ouyang, Ping-Chuan Wang, Zhijian J. Yang
  • Publication number: 20090190413
    Abstract: A method for repairing degraded field effect transistors includes forward biasing PN junctions of one of a source and a drain of a field effect transistor (FET), and a body of the FET. Charge is injected from a substrate to a gate region to neutralize charge in the gate region. The method is applicable to CMOS devices. Repair circuits are disclosed for implementing the repairs.
    Type: Application
    Filed: January 24, 2008
    Publication date: July 30, 2009
    Inventors: Louis L. C. Hsu, Rajiv V. Joshi, Zhijian J. Yang, Ping-Chuan Wang
  • Patent number: 7238565
    Abstract: A method for recovery of degradation caused by avalanche hot carriers is provided that includes subjecting an idle bipolar transistor exhibiting avalanche degradation to a thermal anneal step which increases temperature of the transistor thereby recovering the avalanche degradation of the bipolar transistor. In one embodiment, the annealing source is a self-heating structure that is a Si-containing resistor that is located side by side with an emitter of the bipolar transistor. During the recovering step, the bipolar transistor including the self-heating structure is placed in the idle mode (i.e., without bias) and a current from a separate circuit is flown through the self-heating structure. In another embodiment of the present, the annealing step is a result of providing a high forward current (around the peak fT current or greater) to the bipolar transistor while operating below the avalanche condition (V?CB of less than 1 V).
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: July 3, 2007
    Assignee: International Business Machines Corporation
    Inventors: Fernando Guarin, J. Edwin Hostetter, Jr., Stewart E. Rauch, III, Ping-Chuan Wang, Zhijian J. Yang