Technical Publications / Granted U.S. Patents

Primary Author Technical Publications
Co-Authored Technical Publications
Granted U.S. Patents


Primary Author on the Following Technical Publications:

“A Decade of Solid State Pulsed Power Development at CYMER Inc.”, Proceedings of the 2004 IEEE Power Modulator Conference, San Francisco, CA, 2004.

“Timing and Synchronization of Solid State Pulsed Power Modules (SSPPM) for Excimer Laser Applications”, Proceedings of the 2002 IEEE Power Modulator Conference, Hollywood, CA, 2002, pp. 525-528.

“Solid State Pulsed Power Module (SSPPM) Design for a Dense Plasma Focus (DPF) for Semiconductor Lithography Applications”, Proceedings of the 13th IEEE Pulsed Power Plasma Science Conference, Las Vegas, NV, 2001, pp. 1268-1271.

“Performance Characterization for an Excimer Laser Solid-State Pulsed Power Module (SSPPM) After 20B Shots”, IEEE Transactions on Plasma Science, Volume 28, Number 5, October 2000, pp. 1324-1328.

“A 350 kW Average Power Thyratron Switched Line-Type Modulator”, Proceedings of the 21st Power Modulator Symposium, Costa Mesa, CA, 1994, pp. 34-38.

“Command Resonant Charging System for a 350 kW Average Power Line-Type Modulator”, Proceedings of the 21st Power Modulator Symposium, Costa Mesa, CA, 1994, pp. 159-163.

“Resonance Transformer Power Conditioners”, IEEE Transactions on Electron Devices, 1991, Volume 38 #4, pp. 796-802.

“Compact, Mega-Volt, Rep-Rated Marx Generators”, IEEE Transactions on Electron Devices, 1991, Volume 38 #4, pp. 803-809.

“Resonance Transformer Power Conditioners”, Proceedings of the 19th Power Modulator Symposium, San Diego, CA, 1990, pp. 38-43.

“Compact, Mega-Volt, Rep-Rated Marx Generators”, Proceedings of the 19th Power Modulator Symposium, San Diego, CA, 1990, pp. 477-482.

“A Compact, High Repetition-Rate Trigger Generator”, Proceedings of the 7th IEEE Pulsed Power Conference, Monterrey, CA, 1989, pp. 290-292.

“0.5 MW 60 kHz Solid State Power Modulator”, Proceedings of the 18th Power Modulator Symposium, Hilton Head, SC, 1988, pp. 43-47.

“Multi-cycle Resonant Energy Recovery for Inductive Energy Storage Systems”, Proceedings of the 6th IEEE Pulsed Power Conference, Arlington, VA, 1987, pp. 38-41.

“High Power Switching Using Power FET Arrays”, Proceedings of the 6th IEEE Pulsed Power Conference, Arlington, VA, 1987, pp. 161-164.

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Co-author on the Following Technical Publications:

“Assessing Lock-On Physics in Semi-Insulating GaAs and InP Photoconductive Switches Triggered by Subbandgap Excitation”, with A. Chowdhury et al, IEEE Transactions on Electron Devices, Vol. 65, No. 9, September 2018.

“Development of a 100 kV Pulse Generator for Driving an Electron Scanner Used in Proton Beam Profile Measurements”, with B. Morris et al, Presented at the IEEE 2017 Pulsed Power Conference, Brighton, UK.

“Toward the Development of an Efficient Bulk Semi-Insulating GaN Photoconductive Switch”, with V. Meyers et al, Presented at the IEEE 2017 Pulsed Power Conference, Brighton, UK.

“Evaluation of GaN:Fe as a High Voltage Photoconductive Semiconductor Switch for Pulsed Power Applications”, with D. Mauch et al, Proc. of IEEE 2015 Pulsed Power Conference, Austin, TX.

“Pulse Sharpening and Soliton Generation with Nonlinear Transmission Lines for Producing RF Bursts”, with J.M. Sanders et al, Proc. of IEEE 2010 International Power Modulator and High Voltage Conference (IPMHVC), Atlanta, GA, pp. 604-607.

“XLA-300: the Fourth-Generation ArF MOPA Light Source for Immersion Lithography”, with Fedor Trintchouk et al, Proc. of SPIE Vol. 6154, Optical Microlithography XIX, Donis G. Flagello; Ed., pp. 719-727, (April 2006).

“Evaluation of Nanocrystalline Materials, Amorphous Metal Alloys, and Ferrites for Magnetic Pulse Compression Applications”, with R. Burdt, et al, Journal of Applied Physics, Volume 99, #8, April 26, 2006.

“Loss Estimation of Capacitors in High Rep-Rate Pulsed Power System”, with Chaofeng Huang, et al, Proceedings of the 15th IEEE Pulsed Power Conference, Monterrey, CA, 2005, p. 1077-1080.

“Evaluation of Nanocrystalline Materials, Amorphous Alloys, and Ferrites for Repetitive Magnetic Pulse Compression Applications”, with R. Burdt, et al, Proceedings of the 15th IEEE Pulsed Power Conference, Monterrey, CA, 2005, p. 843-847.

“EUV Discharge Light Source Based on a Dense Plasma Focus Operated with Positive and Negative Polarity”, with Igor Fomenkov, et al, Journal of Physics D Applied Physics, Volume 37, #23, December 7, 2004, pp. 3266-3276.

“IGBT and Diode Loss Measurements in Pulsed Power Operating Conditions”, with Chaofeng Huang, et al, Proceedings of the 2004 IEEE Power Modulator Conference, San Francisco, CA, 2004.

“Performance and Scaling of a Dense Plasma Focus Light Source for EUV Lithography”, with Igor Fomenkov et al, Proc. of SPIE Vol. 5374, Emerging Lithographic Technologies VIII, R. Scott Mackay; Ed., pp. 168-182, (May 2004).

“Low Jitter and Drift High Voltage IGBT Gate Driver”, with Chaofeng Huang, et al, Proceedings of the 14th IEEE Pulsed Power Conference, Dallas, TX, 2003, p. 127-130.

“Evaluation of Magnetic Materials and Insulation Systems for Repetition-Rate Pulse Compression Applications”, with Kenneth McDonald, et al, Proceedings of the 14th IEEE Pulsed Power Conference, Dallas, TX, 2003, p. 603-606.

“Performance and Scaling of a Dense Plasma Focus Light Source for EUV Lithography”, with Igor Fomenkov et al, Proc. of SPIE Vol. 5037, Emerging Lithographic Technologies VII, Roxann L. Engelstad; Ed., pp. 807-821, (Jun 2003).

“Optimization of a Dense Plasma Focus Device as a Light Source for EUV Lithography”, with Igor Fomenkov et al, Proc. of SPIE Vol. 4688, Emerging Lithographic Technologies VI, Roxann L. Engelstad; Ed., pp. 634-647, (Jul 2002).

“Lifetime and Reliability Data of Commercial Excimer Laser Power Systems Modules”, with P. Melcher, et al, Proceedings of the 13th IEEE Pulsed Power Plasma Science Conference, Las Vegas, NV, 2001, pp. 1539-1542.

“Progress Toward Use of a Dense Plasma Focus Device as a Light Source for Production EUV Lithography”, with Bill Partlo et al, Proc. of SPIE Vol. 4343, Emerging Lithographic Technologies V, Elizabeth A. Dobisz, Ed., pp. 232-248, (Aug 2001).

“Timing Compensation for an Excimer Laser Solid-State Pulsed Power Module (SSPPM)”, with D. Johns, et al, IEEE Transactions on Plasma Science, Volume 28, Number 5, October 2000, pp. 1329-1332.

“Comparison of ArF and KrF Laser Performance at 2 kHz for Microlithography”, with Herve Besaucele et al, Proc. SPIE Vol. 4000, Optical Microlithography XIII, Christopher J. Progler; Ed., pp. 1476-1480, (July 2000).

“High Voltage Capacitors Designed to Avoid Catastrophic Failure Modes”, with Fred MacDougall et al, Proceedings of the 12th IEEE Pulsed Power Conference, Monterey, CA, 1999.

“Testing of the SSC DTL and CCL Klystron Modulators”, with B. L. Thomas et al, Proceedings of the 21st Power Modulator Symposium, Costa Mesa, CA, 1994, pp. 144-146.

“Computer Control of High Power Klystron Modulators”, with B. L. Thomas et al, Proceedings of the 21st Power Modulator Symposium, Costa Mesa, CA, 1994, pp. 189-192.

“Thyratron Modulators for the Superconducting Supercollider Drift Tube and Coupled Cavity Linacs”, with B. L. Thomas et al., Proceedings of the 9th IEEE Pulsed Power Conference, Albuquerque, NM, 1993, pp. 873-875.

“An Innovative Fast-Response, Co-axial, Capacitive High Voltage Probe”, with J. R. Cooper et al., Proceedings of the 7th IEEE Pulsed Power Conference, Monterrey, CA, 1989, pp. 390-392.

“Modeling of Self-Breakdown Voltage Statistics in High-Energy Spark Gaps”, with A. L. Donaldson et al., Journal of Applied Physics, 57 #11, pp. 4981-4990, 1985.

“Surface Studies of Dielectric Materials Used in Spark Gaps”, with G. L. Jackson et al., Journal of Applied Physics, 55 #1, pp. 262-268, 1984.

“Modeling of Spark Gap Performance”, with A. L. Donaldson et al., Proceedings of the 4th IEEE Pulsed Power Conference, Albuquerque, NM, 1983, pp. 525-529.

“Surface Studies of Electrodes Used in Spark Gaps”, with G. L. Jackson et al., Proceedings of the 4th IEEE Pulsed Power Conference, Albuquerque, NM, 1983, pp. 534-537.

“Surface Studies of Dielectric Materials Used in Spark Gaps”, with G. L. Jackson et al., Proceedings of the 4th IEEE Pulsed Power Conference, Albuquerque, NM, 1983, pp. 687-690.

“Material Studies in a High Energy Spark Gap”, with L. B. Gordon et al., IEEE Transactions on Plasma Science, PS-10, #4,1982, pp. 286-293.

“Electrode Erosion in High Power Spark Gaps”, with A. L. Donaldson et al., Proceedings of the 15th  Power Modulator Symposium, Boston, MA, 1982.

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Granted U.S. Patents:

U.S. Patent 8,855,166. “6 KHz and Above Gas Discharge Laser System”, with Richard Ujazdowski, Martin Algots, Vladimir Fleurov, Frederick Palenschat, Walter Gillespie, Bryan Moosman, Thomas Steiger, Brett Smith, and Thomas McKelvey, October 7, 2014.

U.S. Patent RE42,588. “Control System for a Two Chamber Gas Discharge Laser System”, with John Fallon, Richard Sandstrom, William Partlo, Alexander Ershov, Toshihiko Ishihara, John Meisner, Paul Melcher, John Rule, and Robert Jacques, August 2, 2011.

U.S. Patent 7,852,899. “Timing Control for Two-Chamber Gas Discharge Laser System”, with Alexander Ershov, December 14, 2010.

U.S. Patent 7,706,424. “Gas Discharge Laser System Electrodes and Power Supply for Delivering Electrical Energy to Same”, with Yoshiho Amada, James Carmichael, and Richard Morton, April 27, 2010.

U.S. Patent 7,596,164. “Control System for a Two Chamber Gas Discharge Laser”, with John Fallon, John Rule, Robert Jacques, Jacob Lipcon, William Partlo, Alexander Ershov, Toshihiko Ishihara, John Meisner, and Paul Melcher, September 29, 2009.

U.S. Patent 7,567,607. “Very Narrow Band, Two Chamber, High Rep-Rate Gas Discharge Laser System”, with David Knowles, Daniel Brown, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Richard Sandstrom, Palash Das, Stuart Anderson, Igor Fomenkov, Richard Ujazdowski, Eckehard Onkels, Scott Smith, William Hulburd, and Jeffrey Oicles, July 28, 2009.

U.S. Patent 7,368,741. “Extreme Ultraviolet Light Source”, with Stephan Melnychuk, William Partlo, Igor Fomenkov, Roger Oliver, Norbert Bowering, Oleh Khodykin, Curtis Rettig, Gerry Blumenstock, Timothy Dyer, Rodney Simmons, Jerzy Hoffman, and Mark Johnson, May 6, 2008.

U.S. Patent 7,218,661. “Line Selected F2 Two Chamber Laser System”, with David Knowles, Daniel Brown, Richard Sandstrom, German Rylov, Eckehard Onkels, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Igor Fomenkov, Richard Ujazdowski, Scott Smith, and William Hulburd, May 15, 2007.

U.S. Patent 7,203,216. “Timing Control for Two-Chamber Gas Discharge Laser System”, with Alexander Ershov, April 10, 2007.

U.S. Patent 7,079,564. “Control System for a Two Chamber Gas Discharge Laser”, with John Fallon, John Rule, Robert Jacques, Jacob Lipcon, William Partlo, Alexander Ershov, Toshihiko Ishihara, John Meisner, and Paul Melcher, July 18, 2006.

U.S. Patent 7,061,961. “Very Narrow Band, Two Chamber, High Reprate Gas Discharge Laser System”, with David Knowles, Daniel Brown, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Richard Sandstrom, Palash Das, Stuart Anderson, Igor Fomenkov, Richard Ujazdowski, Eckehard Onkels, Scott Smith, William Hulburd, and Jeffrey Oicles, June 13, 2006.

U.S. Patent 7,058,107. “Line Selected F2 Two Chamber Laser System”, with David Knowles, Daniel Brown, Richard Sandstrom, German Rylov, Eckehard Onkels, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Igor Fomenkov, Richard Ujazdowski, Scott Smith, and William Hulburd, June 6, 2006.

U.S. Patent 7,039,086. “Control System for a Two Chamber, Gas Discharge Laser”, with John Fallon, John Rule, Robert Jacques, Jacob Lipcon, Richard Sandstrom, William Partlo, Alexander Ershov, Toshihiko Ishihara, John Meisner, and Paul Melcher, May 2, 2006.

U.S. Patent 7,002,443. “Method and Apparatus for Cooling Magnetic Circuit Elements”, with William Partlo, Paul Melcher, George Ferguson, and Robert Saethre, February 21, 2006.

U.S. Patent 6,985,508. “Very Narrow Band, Two Chamber, High Reprate Gas Discharge Laser System”, with David Knowles, Daniel Brown, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Richard Sandstrom, Palash Das, Stuart Anderson, Igor Fomenkov, Richard Ujazdowski, Eckehard Onkels, Scott Smith, William Hulburd, and Jeffrey Oicles, January 10, 2006.>

U.S. Patent 6,972,421. “Extreme Ultraviolet Light Source”, with Stephan Melnychuk, William Partlo, Igor Fomenkov, Roger Oliver, Norbert Bowering, Oleh Khodykin, Curtis Rettig, Gerry Blumenstock, Timothy Dyer, Rodney Simmons, Jerzy Hoffman, and Mark Johnson, December 6, 2005.

U.S. Patent 6,914,919. “Six to Ten kHz, or Greater Gas Discharge Laser System”, with Tom Watson, Richard Ujazdowski, Alex Ivaschenko, Richard Sandstrom, Robert Shannon, Kyle Webb, Frederick Palenschat, Thomas Hofmann, Curtis Rettig, Paul Melcher, and Alexander Ershov, July 5, 2005.

U.S. Patent 6,882,674. “Four kHz Gas Discharge Laser System”, with Christian Wittak, William Partlo, Richard Sandstrom, Paul Melcher, David Johns, Robert Saethre, Curtis Rettig, Robert Shannon, Richard Ujazdowski, Shahryar Rokni, Scott Smith, Stuart Anderson, John Algots, Ronald Spangler,
Igor Fomenkov, Thomas Steiger, Jerome Emilo, Clay Titus, Alex Ivaschenko, Gamaralalage Padmabandu, Paolo Zambon, Mark Branham, Sunjay Phatak, and Raymond Cybulski, April 19, 2005.

U.S. Patent 6,865,210. “Timing Control for Two-Chamber Gas Discharge Laser System”, with Alexander Ershov, March 8, 2005.

U.S. Patent 6,815,700. “Plasma Focus Light Source With Improved Pulse Power System”, with Stephan Melnychuk, William Partlo, Igor Fomenkov, Roger Oliver, Norbert Bowering, and Oleh Khodykin, November 9, 2004.

U.S. Patent 6,801,560. “Line Selected F2 Two Chamber Laser System”, with David Knowles, Daniel Brown, Richard Sandstrom, German Rylov, Eckehard Onkels, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Igor Fomenkov, Richard Ujazdowski, Scott Smith, and William Hulburd, October 5, 2004.

U.S. Patent 6,757,316. “Four KHz Gas Discharge Laser”, with Peter Newman, Thomas Duffey, William Partlo, Richard Sandstrom, Paul Melcher, David Johns, Robert Saethre, Vladimir Fleurov, Curtis Rettig, Robert Shannon, Richard Ujazdowski, Shahryar Rokni, Xiaojiang Pan, Vladimir Kulgeyko, Scott Smith, Stuart Anderson, John Algots, Ronald Spangler, and Igor Fomenkov, June 29, 2004.

U.S. Patent 6,744,060. “Pulse Power System for Extreme Ultraviolet and X-Ray Sources”, with Igor Fomenkov and Bill Partlo, June 1, 2004.

U.S. Patent 6,690,704. “Control System for a Two Chamber, Gas Discharge Laser”, with John Fallon, Richard Sandstrom, Bill Partlo, Alexander Ershov, Toshihiko Ishihara, John Meisner, Paul Melcher, John Rule, and Robert Jacques, February 10, 2004.

U.S. Patent 6,625,191. “Very Narrow Band, Two Chamber, High Rep Rate Gas Discharge Laser System”, with David Knowles, Daniel Brown, Herve Besaucele, David Myers, Alexander Ershov, William Partlo, Richard Sandstrom, Palash Das, Stuart Anderson, Igor Fomenkov, Richard Ujazdowski, Eckehard Onkels, Scott Smith, William Hulburd, and Jeffrey Oicles, September 23, 2003.

U.S. Patent 6,590,922. “Injection Seeded F2 Laser with Line Selection and Discrimination”, with Eckehard Onkels, Richard Sandstrom, William Partlo, Alexander Ershov, and Choonghoon Oh, July 8, 2003.

U.S. Patent 6,586,757. “Plasma Focus Light Source with Active and Buffer Gas Control”, with Stephan Melnychuk, William Partlo, Igor Fomenkov, Daniel Birx, Richard Sandstrom, and John Rauch, July 1, 2003.

U.S. Patent 6,567,450. “Very Narrow Band, Two Chamber, High Rep Rate Gas Discharge Laser System”, with David Myers, Herve Besaucele, Alexander Ershov, William Partlo, Richard Sandstrom, Palash Das, Stuart Anderson, Igor Fomenkov, Richard Ujazdowski, Xiaojiang Pan, Eckehard Onkels, and Daniel Brown, May 20, 2003.

U.S. Patent 6,566,668. “Plasma Focus Light Source with Tandem Ellipsoidal Mirror Units”, with John Rauch, William Partlo, Igor Fomenkov, Daniel Birx, Richard Sandstrom, and Stephan Melnychuk, May 20, 2003.

U.S. Patent 6,566,667. “Plasma Focus Light Source with Improved Pulse Power System”, with William Partlo, Igor Fomenkov, Roger Oliver, and Daniel Birx, May 20, 2003.

U.S. Patent 6,556,600. “Injection Seeded F2 Laser with Centerline Wavelength Control”, with Richard Sandstrom, William Partlo, Alexander Ershov, Eckehard Onkels, and Choonghoon Oh, April 29, 2003.

U.S. Patent 6,549,551. “Injection Seeded Laser with Precise Timing Control”, with Richard Sandstrom, William Partlo, and Alexander Ershov, April 15, 2003.

U.S. Patent RE38,054. “Reliable, Modular, Production Quality Narrow-Band High Rep Rate F2 Laser”, (Re-issue of 6,018,537) with Thomas Hofmann, Jean-Marc Hueber, Palash Das, Toshihiko Ishihara, Thomas Duffey, John Melchior, Herve Besaucele, Richard Morton, Peter Newman, William Partlo, Daniel Rothweil, and Richard Sandstrom, April 1, 2003.

U.S. Patent 6,442,181. “Extreme Repetition Rate Gas Discharge Laser”, with Roger Oliver, William Partlo, Richard Sandstrom, Stuart Anderson, Alex Ivaschenko, James Howey, Vladimir Kulgeyko, Jean-Marc Hueber, and Daniel Birx, August 27, 2002.

U.S. Patent 6,330,261. “Reliable, Modular, Production Quality, Narrow-Band High Rep Rate ArF Excimer Laser”, with Toshihiko Ishihara, Thomas Duffey, John Melchior, Herve Besaucele, Richard Morton, Peter Newman, William Partlo, Daniel Rothweil, and Richard Sandstrom, December 11, 2001.

U.S. Patent 6,327,286. “High Speed Magnetic Modulator Voltage and Temperature Timing Compensation Circuit”, with William Partlo, Richard Sandstrom, and David Johns, December 4, 2001.

U.S. Patent 6,240,112. “High Pulse Rate Pulse Power System With Liquid Cooling”, with William Partlo, Daniel Birx, Deborah Birx, Daniel Rothweil, Paul Melcher, and Brett Smith, May 29, 2001.

U.S. Patent 6,151,346. “High Pulse Rate Pulse Power System With Fast Rise Time and Low Leakage Current”, with William Partlo, Daniel Birx, Daniel Rothweil, Paul Melcher, and Brett Smith, November 21, 2000.

U.S. Patent 6,128,323. “Reliable Modular Production Quality Narrow-Band High Rep Rate Excimer Laser”, with David Myers, Herve Besaucele, Palash Das, Thomas Duffey, Alexander Ershov, Igor Fomenkov, Thomas Hofmann, Richard Morton, Peter Newman, Robert Ozarski, G.G. Padmabandu, William Partlo, Daniel Rothweil, Richard Sandstrom, Paul Thompson, Richard Ujazdowski, Tom Watson, Kyle Webb, and Paolo Zambon, October 3, 2000.

U.S. Patent 6,028,872. “High Pulse Rate Pulse Power System with Resonant Power Supply”, with William Partlo, Daniel Birx, Daniel Rothweil, Paul Melcher, and Brett Smith, February 22, 2000.

U.S. Patent 6,018,537. “Reliable, Modular, Production Quality Narrow-Band High Rep Rate F2 Laser”, with Thomas Hofmann, Jean-Marc Hueber, Palash Das, Toshihiko Ishihara, Thomas Duffey, John Melchior, Herve Besaucele, Richard Morton, Peter Newman, William Partlo, Daniel Rothweil, and Richard Sandstrom, January 25, 2000.

U.S. Patent 6,016,325. “Magnetic Modulator Voltage and Temperature Timing Compensation Circuit”, with William Partlo and Richard Sandstrom, January 18, 2000.

U.S. Patent 5,991,324. “Reliable, Modular, Production Quality Narrow-Band KrF Excimer Laser”, with David Knowles, James Azzola, Herve Besaucele, Palash Das, Alexander Ershov, Igor Fomenkov, Tibor Juhasz, Robert Ozarski, William Partlo, Daniel Rothweil, Richard Sandstrom, Richard Ujazdowski, and Tom Watson, November 23, 1999.

U.S. Patent 5,949,806. “High Voltage Cable Interlock Circuit”, with William Partlo and Richard Sandstrom, September 7, 1999.

U.S. Patent 5,940,421. “Current Reversal Protection Circuit for a Pulsed Gas Discharge Laser”, with William Partlo, and Daniel Birx, August 17, 1999.

U.S. Patent 5,936,988. “High Pulse Rate Pulse Power System”, with William Partlo, Daniel Birx, Daniel Rothweil, Paul Melcher, and Brett Smith, August 10, 1999.

U.S. Patent 5,914,974. “Method and Apparatus for Eliminating Reflected Energy Due to Stage Mismatch in Nonlinear Magnetic Compression Modules”, with William Partlo, Richard Sandstrom, and Daniel Birx, June 22, 1999.

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