Patents by Inventor Jianhong Cai

Jianhong Cai 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: 10116115
    Abstract: A semiconductor device includes an array of VCSEL devices with an annealed oxygen implant region (annealed at a temperature greater than 800° C.) that surrounds and extends laterally between the VCSEL devices. A common anode and a common cathode can be electrically coupled to the VCSEL devices, with the common anode overlying the annealed oxygen implant region. The annealed oxygen implant region can funnel current into active optical regions of the VCSEL devices and provide current isolation between the VCSEL devices while avoiding an isolation etch between VCSEL devices. In another embodiment, a semiconductor device includes an annealed oxygen implant region surrounding a VCSEL device. The VCSEL device(s) can be formed from a multi-junction layer structure where built-in hole charge Qp for an intermediate p-type layer relative to built-in electron charge Qn for a bottom n-type layer is configured for diode-like current-voltage characteristics of the VCSEL device(s).
    Type: Grant
    Filed: February 22, 2017
    Date of Patent: October 30, 2018
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20180241173
    Abstract: A semiconductor device includes an array of VCSEL devices with an annealed oxygen implant region (annealed at a temperature greater than 800° C.) that surrounds and extends laterally between the VCSEL devices. A common anode and a common cathode can be electrically coupled to the VCSEL devices, with the common anode overlying the annealed oxygen implant region. The annealed oxygen implant region can funnel current into active optical regions of the VCSEL devices and provide current isolation between the VCSEL devices while avoiding an isolation etch between VCSEL devices. In another embodiment, a semiconductor device includes an annealed oxygen implant region surrounding a VCSEL device. The VCSEL device(s) can be formed from a multi-junction layer structure where built-in hole charge Qp for an intermediate p-type layer relative to built-in electron charge Qn for a bottom n-type layer is configured for diode-like current-voltage characteristics of the VCSEL device(s).
    Type: Application
    Filed: February 22, 2017
    Publication date: August 23, 2018
    Applicant: INTOP Corp.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 7595516
    Abstract: An optoelectronic circuit includes a resonant cavity formed on a substrate and into which is injected an input digital optical signal that encodes bits of information (each bit representing an OFF logic level or an ON logic level). A heterojunction thyristor device, formed in the resonant cavity, produces an output digital electrical signal corresponding to the input digital optical signal. A sampling clock defines sampling periods that overlap the bits (e.g., ON/OFF pulse durations) in the input digital optical signal. The sampling clock can be in the form of electrical pulses supplied to the n-channel injector terminal(s) and/or p-channel injector terminals of the heterojunction thyristor device. Alternatively, the sampling clock can be in the form of optical pulses that are part of the Optical IN signal that is resonantly absorbed by the device. The heterojunction thyristor device operates in an OFF state and an ON state.
    Type: Grant
    Filed: February 19, 2008
    Date of Patent: September 29, 2009
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 7409120
    Abstract: Interference caused by the propagation of a transmit signal transmitted from a transmit antenna to a receive antenna is effectively cancelled by an improved signal cancellation system. The system includes an interference cancellation signal generator that generates a time-delayed and amplitude-reduced representation of said transmit signal. A summing stage is operably coupled to the interference cancellation signal generator and the receive antenna. The summing stage subtracts the time-delayed and amplitude-reduced representation of the transmit signal from a receive signal to substantially cancel the interference. The interference cancellation signal generator preferably includes a novel programmable optical delay line that introduces a variable amount of optical delay to an optical signal derived from said transmit signal in addition to a thyristor-based sigma delta modulator that converts samples of the transmit signal to into a digital signal in the optical domain.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: August 5, 2008
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai, Daniel C. Upp
  • Publication number: 20080135831
    Abstract: An optoelectronic circuit includes a resonant cavity formed on a substrate and into which is injected an input digital optical signal that encodes bits of information (each bit representing an OFF logic level or an ON logic level). A heterojunction thyristor device, formed in the resonant cavity, produces an output digital electrical signal corresponding to the input digital optical signal. A sampling clock defines sampling periods that overlap the bits (e.g., ON/OFF pulse durations) in the input digital optical signal. The sampling clock can be in the form of electrical pulses supplied to the n-channel injector terminal(s) and/or p-channel injector terminals of the heterojunction thyristor device. Alternatively, the sampling clock can be in the form of optical pulses that are part of the Optical IN signal that is resonantly absorbed by the device. The heterojunction thyristor device operates in an OFF state and an ON state.
    Type: Application
    Filed: February 19, 2008
    Publication date: June 12, 2008
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 7332752
    Abstract: An optoelectronic circuit includes a resonant cavity formed on a substrate and into which is injected an input digital optical signal that encodes bits of information (each bit representing an OFF logic level or an ON logic level). A heterojunction thyristor device, formed in the resonant cavity, produces an output digital electrical signal corresponding to the input digital optical signal. A sampling clock defines sampling periods that overlap the bits (e.g., ON/OFF pulse durations) in the input digital optical signal. The sampling clock can be in the form of electrical pulses supplied to the n-channel injector terminal(s) and/or p-channel injector terminals of the heterojunction thyristor device. Alternatively, the sampling clock can be in the form of optical pulses that are part of the Optical IN signal that is resonantly absorbed by the device. The heterojunction thyristor device operates in an OFF state and an ON state.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: February 19, 2008
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20070019900
    Abstract: Interference caused by the propagation of a transmit signal transmitted from a transmit antenna to a receive antenna is effectively cancelled by an improved signal cancellation system. The system includes an interference cancellation signal generator that generates a time-delayed and amplitude-reduced representation of said transmit signal. A summing stage is operably coupled to the interference cancellation signal generator and the receive antenna. The summing stage subtracts the time-delayed and amplitude-reduced representation of the transmit signal from a receive signal to substantially cancel the interference. The interference cancellation signal generator preferably includes a novel programmable optical delay line that introduces a variable amount of optical delay to an optical signal derived from said transmit signal in addition to a thyristor-based sigma delta modulator that converts samples of the transmit signal to into a digital signal in the optical domain.
    Type: Application
    Filed: June 14, 2006
    Publication date: January 25, 2007
    Inventors: Geoff Taylor, Jianhong Cai, Daniel Upp
  • Patent number: 7064697
    Abstract: Interference caused by the propagation of a transmit signal transmitted from a transmit antenna to a receive antenna is effectively cancelled by an improved signal cancellation system. The system includes an interference cancellation signal generator that generates a time-delayed and amplitude-reduced representation of said transmit signal. A summing stage is operably coupled to the interference cancellation signal generator and the receive antenna. The summing stage subtracts the time-delayed and amplitude-reduced representation of the transmit signal from a receive signal to substantially cancel the interference. The interference cancellation signal generator preferably includes a novel programmable optical delay line that introduces a variable amount of optical delay to an optical signal derived from said transmit signal in addition to a thyristor-based sigma delta modulator that converts samples of the transmit signal to into a digital signal in the optical domain.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: June 20, 2006
    Assignee: The University of Connecticut
    Inventors: Geoff W. Taylor, Jianhong Cai, Daniel C. Upp
  • Patent number: 6995407
    Abstract: A photonic digital-to-analog converter employing a plurality of heterojunction thyristor devices that are configured to convert a digital word encoded by a parallel digital optical signal (e.g., a plurality of synchronous optical bits) to an output analog electrical signal whose magnitude corresponds to the digital word. Each heterojunction thyristor device is configured to convert an optical bit in the digital word to a corresponding digital electrical signal. The voltage levels (e.g., magnitudes) of the ON state of the digital electrical signals produced by the heterojunction thyristor devices may be supplied by voltage divider networks coupled between the cathode terminal of the devices and ground potential or voltage reference sources coupled to the input terminals of the heterojunction thyristor devices. In this manner, electrical signals whose magnitude corresponds to contribution of each optical bit in the digital word are produced.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: February 7, 2006
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 6954473
    Abstract: An optoelectronic integrated circuit includes a resonant cavity formed on a substrate. A heterojunction thyristor device is formed in the resonant cavity and operates to detect an input optical pulse (or input electrical pulse) and produce an output optical pulse via laser emission in response to the detected input pulse. The heterojunction thyristor device includes a channel region that is coupled to a current source that draws current from the channel region. Time delay between the input pulse and output optical pulse may be varied by configuring the current source to draw constant current from the channel region and modulating the intensity of the input pulse, or by varying the amount of current drawn from the channel region by the current source. The heterojunction thyristor device may be formed from a multilayer structure of group III-V materials, or from a multilayer structure of strained silicon materials.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: October 11, 2005
    Assignees: Opel, Inc., The University of Connecticut
    Inventors: Rohinton Dehmubed, Geoff W. Taylor, Daniel C. Upp, Jianhong Cai
  • Patent number: 6873273
    Abstract: A serial photonic digital-to-analog converter employs a heterojunction thyristor device configured for optically-controlled sampling/switching to convert a digital word encoded by a serial digital optical data signal (e.g., serial optical bit stream) into a corresponding analog electrical signal. A voltage reference is operably coupled to the electrical input terminal of the heterojunction thyristor device. The voltage reference cooperates with the heterojunction thyristor device to sequentially generate at its electrical output terminal a voltage signal representing contribution of each bit of the digital word encoded in the serial digital optical data signal. A summing network is operably coupled to the electrical output terminal of the device. The summing network sequentially sums contribution of the voltage signal over the sequence of bits to produce an analog electrical signal corresponding to the digital word for output therefrom.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: March 29, 2005
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 6853014
    Abstract: An optoelectronic circuit employing a heterojunction thyristor device that is configured as an optically-controlled (or electrically-controlled) sampling/switching device. First and second channel regions are disposed between the anode terminal and the cathode terminal of the device, and an electrical input terminal and an electrical output terminal are coupled to opposite ends of the first channel region. At least one control signal is supplied to the device. When the control signal corresponds to a predetermined ON condition, sufficient charge is stored in the second channel region to cause the heterojunction thyristor device to operate in an ON state whereby current flows between the anode terminal and the cathode terminal and the electrical input terminal is electrically coupled to the electrical output terminal.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: February 8, 2005
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Patent number: 6841806
    Abstract: An integrated circuit includes a heterojunction thyristor device having an anode terminal, a cathode terminal, a first injector terminal operably coupled to a first quantum well channel disposed between the anode terminal and the cathode terminal, and a second injector terminal operably coupled to a second quantum well channel disposed between the anode terminal and the cathode terminal. Bias elements operate the heterojunction thyristor device in a mode that provides substantially linear voltage gain for electrical signals supplied to at least one of the first and second injector terminals for output to at least one output node.
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: January 11, 2005
    Assignees: The University of Connecticut, Opel, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20040262593
    Abstract: An integrated circuit includes a heterojunction thyristor device having an anode terminal, a cathode terminal, a first injector terminal operably coupled to a first quantum well channel disposed between the anode terminal and the cathode terminal, and a second injector terminal operably coupled to a second quantum well channel disposed between the anode terminal and the cathode terminal. Bias elements operate the heterojunction thyristor device in a mode that provides substantially linear voltage gain for electrical signals supplied to at least one of the first and second injector terminals for output to at least one output node.
    Type: Application
    Filed: June 24, 2003
    Publication date: December 30, 2004
    Applicants: University of Connecticut, OPEL, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20040146237
    Abstract: Interference caused by the propagation of a transmit signal transmitted from a transmit antenna to a receive antenna is effectively cancelled by an improved signal cancellation system. The system includes an interference cancellation signal generator that generates a time-delayed and amplitude-reduced representation of said transmit signal. A summing stage is operably coupled to the interference cancellation signal generator and the receive antenna. The summing stage subtracts the time-delayed and amplitude-reduced representation of the transmit signal from a receive signal to substantially cancel the interference. The interference cancellation signal generator preferably includes a novel programmable optical delay line that introduces a variable amount of optical delay to an optical signal derived from said transmit signal in addition to a thyristor-based sigma delta modulator that converts samples of the transmit signal to into a digital signal in the optical domain.
    Type: Application
    Filed: June 24, 2003
    Publication date: July 29, 2004
    Inventors: Geoff W. Taylor, Jianhong Cai, Daniel C. Upp
  • Publication number: 20040094760
    Abstract: An optoelectronic circuit includes a resonant cavity formed on a substrate and into which is injected an input digital optical signal that encodes bits of information (each bit representing an OFF logic level or an ON logic level). A heterojunction thyristor device, formed in the resonant cavity, produces an output digital electrical signal corresponding to the input digital optical signal. A sampling clock defines sampling periods that overlap the bits (e.g., ON/OFF pulse durations) in the input digital optical signal. The sampling clock can be in the form of electrical pulses supplied to the n-channel injector terminal(s) and/or p-channel injector terminals of the heterojunction thyristor device. Alternatively, the sampling clock can be in the form of optical pulses that are part of the Optical IN signal that is resonantly absorbed by the device. The heterojunction thyristor device operates in an OFF state and an ON state.
    Type: Application
    Filed: December 19, 2002
    Publication date: May 20, 2004
    Applicants: The University of Connecticut, OPEL, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20040079939
    Abstract: A serial photonic digital-to-analog converter employs a heterojunction thyristor device configured for optically-controlled sampling/switching to convert a digital word encoded by a serial digital optical data signal (e.g., serial optical bit stream) into a corresponding analog electrical signal. A voltage reference is operably coupled to the electrical input terminal of the heterojunction thyristor device. The voltage reference cooperates with the heterojunction thyristor device to sequentially generate at its electrical output terminal a voltage signal representing contribution of each bit of the digital word encoded in the serial digital optical data signal. A summing network is operably coupled to the electrical output terminal of the device. The summing network sequentially sums contribution of the voltage signal over the sequence of bits to produce an analog electrical signal corresponding to the digital word for output therefrom.
    Type: Application
    Filed: December 19, 2002
    Publication date: April 29, 2004
    Applicants: The University of Connecticut, OPEL, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20040081216
    Abstract: An optoelectronic integrated circuit includes a resonant cavity formed on a substrate. A heterojunction thyristor device is formed in the resonant cavity and operates to detect an input optical pulse (or input electrical pulse) and produce an output optical pulse via laser emission in response to the detected input pulse. The heterojunction thyristor device includes a channel region that is coupled to a current source that draws current from the channel region. Time delay between the input pulse and output optical pulse may be varied by configuring the current source to draw constant current from the channel region and modulating the intensity of the input pulse, or by varying the amount of current drawn from the channel region by the current source. The heterojunction thyristor device may be formed from a multilayer structure of group III-V materials, or from a multilayer structure of strained silicon materials.
    Type: Application
    Filed: October 25, 2002
    Publication date: April 29, 2004
    Inventors: Rohinton Dehmubed, Geoff W. Taylor, Daniel C. Upp, Jianhong Cai
  • Publication number: 20040079961
    Abstract: A photonic digital-to-analog converter employing a plurality of heterojunction thyristor devices that are configured to convert a digital word encoded by a parallel digital optical signal (e.g., a plurality of synchronous optical bits) to an output analog electrical signal whose magnitude corresponds to the digital word. Each heterojunction thyristor device is configured to convert an optical bit in the digital word to a corresponding digital electrical signal. The voltage levels (e.g., magnitudes) of the ON state of the digital electrical signals produced by the heterojunction thyristor devices may be supplied by voltage divider networks coupled between the cathode terminal of the devices and ground potential or voltage reference sources coupled to the input terminals of the heterojunction thyristor devices. In this manner, electrical signals whose magnitude corresponds to contribution of each optical bit in the digital word are produced.
    Type: Application
    Filed: December 19, 2002
    Publication date: April 29, 2004
    Applicants: The University of Connecticut, OPEL, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai
  • Publication number: 20040079963
    Abstract: An optoelectronic circuit employing a heterojunction thyristor device that is configured as an optically-controlled (or electrically-controlled) sampling/switching device. First and second channel regions are disposed between the anode terminal and the cathode terminal of the device, and an electrical input terminal and an electrical output terminal are coupled to opposite ends of the first channel region. At least one control signal is supplied to the device. When the control signal corresponds to a predetermined ON condition, sufficient charge is stored in the second channel region to cause the heterojunction thyristor device to operate in an ON state whereby current flows between the anode terminal and the cathode terminal and the electrical input terminal is electrically coupled to the electrical output terminal.
    Type: Application
    Filed: December 19, 2002
    Publication date: April 29, 2004
    Applicants: The University of Connecticut, OPEL, Inc.
    Inventors: Geoff W. Taylor, Jianhong Cai