Patents by Inventor James C. Gallagher
James C. Gallagher 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: 11817318Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: GrantFiled: March 1, 2023Date of Patent: November 14, 2023Assignee: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20230207323Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: ApplicationFiled: March 1, 2023Publication date: June 29, 2023Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Patent number: 11532478Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: GrantFiled: November 8, 2021Date of Patent: December 20, 2022Assignee: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Patent number: 11415518Abstract: A method for mapping and analyzing a GaN substrate to identify areas of the substrate suitable for fabrication of electronic devices thereon. Raman spectroscopy is performed over the surface of a GaN substrate to produce maps of the E2 and A1 peaks at a plurality of areas on the substrate surface, the E2 and A1 peaks being associated with known concentrations of defects and charge carriers, so that areas of the GaN substrate having relatively high resistivity or conductivity which make those areas suitable or unsuitable for fabrication of electronic devices can be identified. The devices can then be fabricated only on suitable areas of the substrate, or the size of the devices can be tailored to maximize the yield of devices fabricated thereon. Substrates not meeting a threshold level of defect and/or charge carrier concentration can be discarded without fabrication of poor-quality devices thereon.Type: GrantFiled: June 19, 2020Date of Patent: August 16, 2022Assignee: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, Jennifer K. Hite, James C. Gallagher, Karl D. Hobart
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Publication number: 20220254639Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: ApplicationFiled: January 26, 2022Publication date: August 11, 2022Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20220059352Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: ApplicationFiled: November 8, 2021Publication date: February 24, 2022Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20220059353Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: ApplicationFiled: November 8, 2021Publication date: February 24, 2022Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20210389126Abstract: An improved method for evaluating GaN wafers. RMS analysis of wafer heights obtained by optical interferometric profilometry is combined with an extreme Studentized deviate (ESD) analysis to obtain a map of the wafer surface that more accurately identifies areas on the surface of a GaN wafer having defects that making those areas unsuitable for fabrication of a vertical electronic device thereon such as bumps and/or pits that can lower the breakdown voltage, increase the on-resistance, and increase the ideality factor.Type: ApplicationFiled: June 11, 2021Publication date: December 16, 2021Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: James C. Gallagher, Travis J. Anderson, Jennifer K. Hite, Karl D. Hobart
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Patent number: 11201058Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: GrantFiled: July 13, 2020Date of Patent: December 14, 2021Assignee: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20210028020Abstract: A method for activating implanted dopants and repairing damage to dopant-implanted GaN to form n-type or p-type GaN. A GaN substrate is implanted with n- or p-type ions and is subjected to a high-temperature anneal to activate the implanted dopants and to produce planar n- or p-type doped areas within the GaN having an activated dopant concentration of about 1018-1022 cm?3. An initial annealing at a temperature at which the GaN is stable at a predetermined process temperature for a predetermined time can be conducted before the high-temperature anneal. A thermally stable cap can be applied to the GaN substrate to suppress nitrogen evolution from the GaN surface during the high-temperature annealing step. The high-temperature annealing can be conducted under N2 pressure to increase the stability of the GaN. The annealing can be conducted using laser annealing or rapid thermal annealing (RTA).Type: ApplicationFiled: July 13, 2020Publication date: January 28, 2021Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, James C. Gallagher, Marko J. Tadjer, Alan G. Jacobs, Boris N. Feigelson
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Publication number: 20200400578Abstract: A method for mapping and analyzing a GaN substrate to identify areas of the substrate suitable for fabrication of electronic devices thereon. Raman spectroscopy is performed over the surface of a GaN substrate to produce maps of the E2 and A1 peaks at a plurality of areas on the substrate surface, the E2 and A1 peaks being associated with known concentrations of defects and charge carriers, so that areas of the GaN substrate having relatively high resistivity or conductivity which make those areas suitable or unsuitable for fabrication of electronic devices can be identified. The devices can then be fabricated only on suitable areas of the substrate, or the size of the devices can be tailored to maximize the yield of devices fabricated thereon. Substrates not meeting a threshold level of defect and/or charge carrier concentration can be discarded without fabrication of poor-quality devices thereon.Type: ApplicationFiled: June 19, 2020Publication date: December 24, 2020Applicant: The Government of the United States of America, as represented by the Secretary of the NavyInventors: Travis J. Anderson, Jennifer K. Hite, James C. Gallagher, Karl D. Hobart
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Patent number: 5005101Abstract: An improved apparatus for generating a negative charge effect in the environment, in which opposite charged spaced electrically conductive plates are dielectric material. A relatively high alternating voltage is applied between alternate spaced plates with sufficient dielectric strength and dielectric constant to withstand the generation of a cold glow discharge or plasma, and withstand the deposit of dirt on them, and withstand exposure to corrosion, humidity, high temperatures, corrosive gases and fumes. A process is disclosed for the separation of undesirable gases and particulates in polluted areas or airstreams. The present invention relates to the excitation, dissociation, and breakdown of gases and other pollutants.Type: GrantFiled: January 31, 1989Date of Patent: April 2, 1991Inventors: James C. Gallagher, Michael K. Gallagher
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Patent number: 4109290Abstract: An improved means for generating a negative charge effect in the environment, in which oppositely charged electrically conductive plates are coated with secondary emissive material and are enclosed in a sealed container such as glass that is preferably filled with an inert gas such as argon.Type: GrantFiled: April 18, 1977Date of Patent: August 22, 1978Assignee: APSEE, IncorporatedInventor: James C. Gallagher