Patents by Inventor Lars F. Voss
Lars F. Voss 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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Publication number: 20240120428Abstract: Devices, methods and techniques related to high voltage and high-power diamond transistors are disclosed. In one example aspect, a switch operable under high-voltage and high-power includes a P-type diamond layer doped with an acceptor material, a first N-type diamond layer doped with a donor material and in contact with one side of the P-type diamond layer, a light blocking layer comprising the one or more apertures configured to allow the light to enter the first N-type diamond layer, a source contact and a drain contact that are at least partially in contact with the P-type diamond layer, and the gate in contact with at least an area of the first N-type diamond layer that corresponds to one of the one or more apertures. The gate can be positioned on the backside of the substrate.Type: ApplicationFiled: October 4, 2023Publication date: April 11, 2024Inventors: Qinghui Shao, Lars F. Voss
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Patent number: 11942760Abstract: A high-voltage switch, whose operation leverages the speed of electrons to generate the “on” time of the pulse in combination with the speed of light to generate the “off” time of the pulse, is described. In one example, the high-voltage switch includes a first electrode, a second electrode spaced apart from the first electrode, a region of non-absorbing material occupying a portion of the space between the first and second electrodes and allowing a laser pulse to propagate therethrough without substantial absorption, and a region of absorbing material occupying another portion of the space and producing a charged particle cloud upon receiving the laser pulse. The high-voltage switch remains “on” upon the charged particle cloud reaching an electrode and until it has been collected by the electrode, and where the high-voltage switch remains “off” subsequent to the collection and until another generated charged particle cloud reaches the electrode.Type: GrantFiled: December 19, 2018Date of Patent: March 26, 2024Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLCInventors: Lars F. Voss, Adam M. Conway, John E. Heebner
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Publication number: 20240047516Abstract: An apparatus, in accordance with one embodiment, includes a superjunction device having a voltage sustaining layer formed of a semiconductor material and a dopant in the voltage sustaining layer. The dopant is for distributing an electric field within the voltage sustaining layer. The dopant is more concentrated along a sidewall of the voltage sustaining layer than toward a center of the voltage sustaining layer, the sidewall extending at least a portion of the distance between a top surface and a bottom surface of a voltage sustaining layer. Methods of electric field-enhanced dopant diffusion to form a superjunction device are also presented.Type: ApplicationFiled: August 3, 2022Publication date: February 8, 2024Inventors: Vincenzo Lordi, Noah Patrick Allen, Qinghui Shao, Clint Duncan Frye, Kyoung Eun Kweon, Lars F. Voss, Joel Basile Varley
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Patent number: 11805715Abstract: A photoconductive switch that uses materials that support negative differential mobility, whose operation leverages the pulse compression of a charge could to generate the “on” time of the pulse in combination with the speed of light to generate the “off” time of the pulse, is described. In one example, a method of operating a photoconductive switch, which includes two electrodes and a light absorbing material positioned therebetween, includes selecting a value for one or more parameters comprising a voltage for generation of an electric field, a spot size of a laser pulse, a temporal pulse width of the laser pulse, or an intensity of the laser pulse, wherein the selected value(s) for the one or more parameters enable the switch to operate in a region where the light absorbing material exhibits negative differential mobility, and illuminating the light absorbing material with the laser pulse to generate a charge cloud within the light absorbing material.Type: GrantFiled: October 15, 2021Date of Patent: October 31, 2023Assignees: LAWRENCE LIVERMORE NATIONAL SECURITY, LLC, THE BOARD OF TRUSTEES OF THE UNIVERSITY OF ILLINOISInventors: Lars F. Voss, Adam Conway, Karen Marie Dowling, David Lawrence Hall, Shaloo Rakheja, Kexin Li
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Publication number: 20230216469Abstract: Disclosed are apparatuses and methods of tuning a radio frequency circuit using stub tuners and photoconductive switches. In one aspect an electromagnetic stub tuner apparatus is disclosed. the apparatus includes a transmission line, and a photoconductive switch positioned along the length of the transmission line. The photoconductive switch is configured to turn on or turn off, wherein an impedance of the transmission line is changed when the photoconductive switch is turned on compared to when the photoconductive switch is turned off. In another aspect, a method of tuning a radio frequency circuit is disclosed. In yet another aspect, a method of producing a radio frequency tuning circuit is disclosed.Type: ApplicationFiled: December 28, 2021Publication date: July 6, 2023Inventors: Tammy Chang, Lars F. Voss, Joseph D. Schneider
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GYROMAGNETIC NONLINEAR TRANSMISSION LINE FOR RADIO FREQUENCY SIGNAL GENERATION AND PULSE COMPRESSION
Publication number: 20230198116Abstract: Disclosed are non-linear transmission lines using ferromagnetic materials to generate ferromagnetic resonance oscillations. In one aspect, a non-linear transmission line apparatus is disclosed. The apparatus includes an outer conductor having a first side and a second internally facing side, and an inner conductor positioned internal to the non-linear transmission line apparatus. The apparatus further includes a ferromagnetic material surrounding the inner conductor, wherein the ferromagnetic material comprises nanoparticles of an ?-polymorph of iron oxide expressed as ?—Fe2O3. The apparatus also includes a first dielectric material positioned between the outer conductor and the inner conductor, the dielectric material in contact with both the ferromagnetic material and with the second internally facing side of the outer conductor, wherein the outer conductor, the inner conductor, the dielectric material and the ferromagnetic material form the nonlinear transmission line.Type: ApplicationFiled: December 20, 2021Publication date: June 22, 2023Inventors: Joseph Devin Schneider, Alexander Adrian Baker, Jinkyu Han, Lars F. Voss -
Publication number: 20230121080Abstract: In one general embodiment, a structure includes a first diode, comprising: a first layer having a first type of dopant, and a second layer above the first layer, the second layer having a second type of dopant that is opposite to the first type of dopant. A second diode is formed directly on the first diode. The second diode comprises a first layer having a third type of dopant and a second layer above the first layer of the second diode, the second layer of the second diode having a fourth type of dopant that is opposite to the third type of dopant. In another general embodiment, a process includes a repeated sequence of growing a first layer having a first type of electrically active dopant and growing a second layer having a second type of electrically active dopant that is opposite to the first type of dopant.Type: ApplicationFiled: October 17, 2022Publication date: April 20, 2023Inventors: Caitlin Anne Chapin, Lars F. Voss, Luis M. Hernandez, Mark Rader
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Patent number: 11555965Abstract: Methods and devices for illuminating a photoconductive switch consisting of an optically actuated photoconductive material situated between two electrodes are described. Light from a light source is coupled to an optical fiber, which is attached to a frustum, the other side of which is proximate to the photoconductive switch. Light from the optical fiber enters the frustum, spreads out, and enters the photoconductive switch via the top-side electrode. Some of the light is absorbed, while the remaining light reflects off the bottom-side electrode, travels back through the photoconductive switch, and any unabsorbed light reenters the frustum. The geometry of the frustum is configured such that most of the light reflects back into the switch itself with only a negligible fraction escaping from the optical fiber, which advantageously results in near total utilization of the light.Type: GrantFiled: July 9, 2021Date of Patent: January 17, 2023Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLCInventors: Michael Rushford, Adam Conway, Lars F. Voss, Joseph D. Schneider, Tammy Chang, Caitlin Anne Chapin, John Berns Lancaster, Steve Hawkins, Victor Valeryevich Khitrov
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Publication number: 20230011108Abstract: Methods and devices for illuminating a photoconductive switch consisting of an optically actuated photoconductive material situated between two electrodes are described. Light from a light source is coupled to an optical fiber, which is attached to a frustum, the other side of which is proximate to the photoconductive switch. Light from the optical fiber enters the frustum, spreads out, and enters the photoconductive switch via the top-side electrode. Some of the light is absorbed, while the remaining light reflects off the bottom-side electrode, travels back through the photoconductive switch, and any unabsorbed light reenters the frustum. The geometry of the frustum is configured such that most of the light reflects back into the switch itself with only a negligible fraction escaping from the optical fiber, which advantageously results in near total utilization of the light.Type: ApplicationFiled: July 9, 2021Publication date: January 12, 2023Inventors: Michael Rushford, Adam Conway, Lars F. Voss, Joseph D. Schneider, Tammy Chang, Caitlin Anne Chapin, John Berns Lancaster, Steve Hawkins, Victor Valeryevich Khitrov
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Patent number: 11522542Abstract: A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideband optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.Type: GrantFiled: June 3, 2019Date of Patent: December 6, 2022Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLCInventors: Lars F. Voss, Adam M. Conway
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Publication number: 20220352889Abstract: A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideb and optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.Type: ApplicationFiled: July 12, 2022Publication date: November 3, 2022Inventors: Lars F. Voss, Adam M. Conway
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Patent number: 11322626Abstract: Devices, methods and techniques are disclosed for providing a multi-layer diode without voids between layers. In one example aspect, a multi-stack diode includes at least two Drift Step Recovery Diodes (DSRDs). Each DSRD comprises a first layer having a first type of dopant, a second layer forming a region with at least ten times lower concentration of dopants compared to the adjacent layers, and a third layer having a second type of dopant that is opposite to the first type of dopant. The first layer of a second DSRD is positioned on top of the third layer of first DSRD. The first layer of the second DSRD and the third layer of the first DSRD are degenerate to form a tunneling diode at an interface of the first DSRD and second DSRD, the tunneling diode demonstrating a linear current-voltage characteristic.Type: GrantFiled: October 27, 2020Date of Patent: May 3, 2022Assignees: Lawrence Livermore National Security, LLC, BAE Systems Land & Armaments L.P., The Government of the United States, as represented by the Secretary of the ArmyInventors: Lars F. Voss, Adam M. Conway, Luis M. Hernandez, Mark S. Rader
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Publication number: 20220123211Abstract: A photoconductive switch that uses materials that support negative differential mobility, whose operation leverages the pulse compression of a charge could to generate the “on” time of the pulse in combination with the speed of light to generate the “off” time of the pulse, is described. In one example, a method of operating a photoconductive switch, which includes two electrodes and a light absorbing material positioned therebetween, includes selecting a value for one or more parameters comprising a voltage for generation of an electric field, a spot size of a laser pulse, a temporal pulse width of the laser pulse, or an intensity of the laser pulse, wherein the selected value(s) for the one or more parameters enable the switch to operate in a region where the light absorbing material exhibits negative differential mobility, and illuminating the light absorbing material with the laser pulse to generate a charge cloud within the light absorbing material.Type: ApplicationFiled: October 15, 2021Publication date: April 21, 2022Inventors: Lars F. Voss, Adam Conway, Karen Marie Dowling, David Lawrence Hall, Shaloo Rakheja, Kexin Li
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Publication number: 20220040463Abstract: A product includes an elongated carbon-containing pillar having a bottom and a tip opposite the bottom. The width of the pillar measured 1 nm below the tip is less than 700 nm. A method includes masking a carbon-containing single crystal for defining masked regions and unmasked regions on the single crystal. The method also includes performing a plasma etch for removing portions of the unmasked regions of the single crystal, thereby defining a pillar in each unmasked region, and performing a chemical etch on the pillars at a temperature between 1200° C. and 1600° C. for selectively reducing a width of each pillar.Type: ApplicationFiled: August 6, 2020Publication date: February 10, 2022Inventors: Clint D. Frye, Mihail Bora, Adam M. Conway, Devin Joseph Funaro, Paulius Vytautas Grivickas, David L. Hall, Lars F. Voss
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Publication number: 20210336131Abstract: A high-voltage switch, whose operation leverages the speed of electrons to generate the “on” time of the pulse in combination with the speed of light to generate the “off” time of the pulse, is described. In one example, the high-voltage switch includes a first electrode, a second electrode spaced apart from the first electrode, a region of non-absorbing material occupying a portion of the space between the first and second electrodes and allowing a laser pulse to propagate therethrough without substantial absorption, and a region of absorbing material occupying another portion of the space and producing a charged particle cloud upon receiving the laser pulse. The high-voltage switch remains “on” upon the charged particle cloud reaching an electrode and until it has been collected by the electrode, and where the high-voltage switch remains “off” subsequent to the collection and until another generated charged particle cloud reaches the electrode.Type: ApplicationFiled: December 19, 2018Publication date: October 28, 2021Inventors: Lars F. Voss, Adam M. Conway, John E. Heebner
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Patent number: 11133190Abstract: According to one embodiment, a method includes performing a plasma etching process on a masked III-V semiconductor, and forming a passivation layer on etched portions of the III-V semiconductor. The passivation layer includes at least one of a group III element and/or a metal from the following: Ni, Cr, W, Mo, Pt, Pd, Mg, Ti, Zr, Hf, Y, Ta, and Sc.Type: GrantFiled: May 4, 2018Date of Patent: September 28, 2021Assignee: Lawrence Livermore National Security, LLCInventors: Sara E. Harrison, Clint Frye, Rebecca J. Nikolic, Qinghui Shao, Lars F. Voss
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Publication number: 20210126136Abstract: Devices, methods and techniques are disclosed for providing a multi-layer diode without voids between layers. In one example aspect, a multi-stack diode includes at least two Drift Step Recovery Diodes (DSRDs). Each DSRD comprises a first layer having a first type of dopant, a second layer forming a region with at least ten times lower concentration of dopants compared to the adjacent layers, and a third layer having a second type of dopant that is opposite to the first type of dopant. The first layer of a second DSRD is positioned on top of the third layer of first DSRD. The first layer of the second DSRD and the third layer of the first DSRD are degenerate to form a tunneling diode at an interface of the first DSRD and second DSRD, the tunneling diode demonstrating a linear current-voltage characteristic.Type: ApplicationFiled: October 27, 2020Publication date: April 29, 2021Inventors: Lars F. Voss, Adam M. Conway
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Patent number: 10992105Abstract: A coating having a mismatched coefficient of thermal expansion is applied to an underlying light emitting diode (LED) or laser diode (LD), such that as the temperature of the device changes, a varying level of strain is introduced to the underlying LED or LD. Because strain can also adjust the effective bandgap energy (and hence emission wavelength) of the device, the external strain-inducing coating can act to either compensate for the wavelength shift due to temperature (resulting in reduced d?/dT) or accentuate it (resulting in increased d?/dT). By proper selection of coating material and geometry, full control over d?/dT can be achieved.Type: GrantFiled: June 7, 2019Date of Patent: April 27, 2021Assignee: LAWRENCE LIVERMORE NATIONAL SECURITY, LLCInventors: Lars F. Voss, Paul O. Leisher
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Publication number: 20200382118Abstract: A high-voltage switch is adapted for use as a medium-voltage direct current circuit breaker, which provides a low-cost, small-footprint device to mitigate system faults. In one example, a method for operating a wideband optical device includes illuminating the wide bandgap optical device with a light within a first range of wavelengths and a first average intensity, allowing a current to propagate therethrough without substantial absorption of the current, illuminating the wide bandgap optical device with light within the first range of wavelengths and a second average intensity that is lower than the first average intensity to allow a sustained current flow though the wide bandgap optical device, and illuminating the wide bandgap optical device with light within a second range of wavelengths to stop or substantially restrict propagation of the current through the wide gap material.Type: ApplicationFiled: June 3, 2019Publication date: December 3, 2020Inventors: Lars F. Voss, Adam M. Conway
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Patent number: 10699820Abstract: According to one embodiment, a product includes an array of three dimensional structures, where each of the three dimensional structure includes a semiconductor material; a cavity region between each of the three dimensional structures; and a first material in contact with at least one surface of each of the three dimensional structures, where the first material is configured to provide high energy particle and/or ray emissions.Type: GrantFiled: March 14, 2014Date of Patent: June 30, 2020Assignee: Lawrence Livermore National Security, LLCInventors: Rebecca J. Nikolic, Adam P. Conway, Roger A. Henderson, Victor P. Karpenko, Qinghui Shao, Dawn A. Shaughnessy, Mark A. Stoyer, Lars F. Voss