Patents by Inventor Donald G. Larson

Donald G. Larson 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: 6034978
    Abstract: A gas discharge laser with fast response gas temperature control to maintain laser gas temperature within desired limits during burst mode operation. Preferred embodiments include a passive temperature stabilizer having fins with surface areas exposed to flowing laser gas at least equal to the surface area of the cooling fins of a laser gas heat exchanger. Preferred embodiments utilize heating elements and coolant flow control to regulate laser gas temperatures using processors programmed to anticipate idle periods.
    Type: Grant
    Filed: May 12, 1999
    Date of Patent: March 7, 2000
    Assignee: Cymer, Inc.
    Inventors: Richard C. Ujazdowski, Robert A. Shannon, Dmitry Berger, William N. Partlo, Tom A. Watson, Paul S. Thompson, Toshihiko Ishihara, Carl E. Tedesco, II, Donald G. Larson, Steven M. Harrington, Richard G. Morton, James H. Azzola, I. Roger Oliver, Thomas P. Duffey, Igor V. Fomenkov
  • Patent number: 6021150
    Abstract: Disclosed is a laser useful in, e.g., photolithography or medical surgery. In one embodiment, the laser comprises a discharge chamber and heat-generating electronics that are enclosed in a baffled enclosure that requires less cooling air to reliably cool the components in the enclosure than previous unbaffled enclosures. A method of reducing the amount of conditioned air is also provided. In a further embodiment, the laser has a heat-exchange system that acts quickly in response to changes in laser gas temperature by adjusting a flow-proportioning valve regulating water flow through a heat exchanger, thereby providing a continuously variable rate of heat exchange through the heat exchanger to maintain the lasing gas temperature constant. Methods of providing a laser beam and of improving the uniformity of a laser beam are disclosed, as are photolithography methods utilizing a laser and method of this invention.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: February 1, 2000
    Assignee: Cymer, Inc.
    Inventors: William N. Partio, Donald G. Larson, Igor V. Fomenkov, Anthony J. de Ruyter, Palash P. Das
  • Patent number: 5848089
    Abstract: An electric discharge gas laser having a laser cavity in which is contained a laser gas and a fan for circulating the laser gas. The fan is supported by an active magnetic bearing system and driven by a brushless DC motor in which the rotor of the motor and at least two magnetic bearings sealed within the gas environment of the laser cavity and the motor stator and the coils of the bearing magnets are located outside the gas environment.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: December 8, 1998
    Assignee: Cymer, Inc.
    Inventors: Kamal Sarkar, Richard C. Ujazdowski, Palash P. Das, Donald G. Larson
  • Patent number: 5748656
    Abstract: Disclosed is a laser useful in, e.g., photolithography or medical surgery. In one embodiment, the laser comprises a discharge chamber and heat-generating electronics that are enclosed in a baffled enclosure that requires less cooling air to reliably cool the components in the enclosure than previous unbaffled enclosures. A method of reducing the amount of conditioned air is also provided. In a further embodiment, the laser has a heat-exchange system that acts quickly in response to changes in laser gas temperature by adjusting a flow-proportioning valve regulating water flow through a heat exchanger, thereby providing a continuously variable rate of heat exchange through the heat exchanger to maintain the lasing gas temperature constant. Methods of providing a laser beam and of improving the uniformity of a laser beam are disclosed, as are photolithography methods utilizing a laser and method of this invention.
    Type: Grant
    Filed: January 5, 1996
    Date of Patent: May 5, 1998
    Assignee: Cymer, Inc.
    Inventors: Tom A. Watson, William N. Partlo, Donald G. Larson, Igor V. Fomenkov, Anthony J. de Ruyter, Palash P. Das
  • Patent number: 5586134
    Abstract: A housing in a laser system encloses a cathode and a displaced anode and gases ionizable and reactive chemically when a voltage pulse produces a cathode-anode electrical discharge. Moving air cools the components (capacitors, thyratron and triggering circuitry) for producing the voltage pulses. The laser gas temperature is continuously regulated at a particular value whether or not there is an electrical discharge. The concentration of one of the gases in the chamber is regulated to values alternately on opposite sides of an optimal value to provide an optimal energy in each chemical reaction of the gases. The gases are recirculated as by a fan driven on a shaft by a pair of motors and are filtered during such recirculation. The shaft speed is regulated at a particular value and the motor currents are regulated to be equal. Any ozone formed in a compartment holding the high voltage terminals is purged by passing a neutral gas (nitrogen) through the compartment to the atmosphere.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: December 17, 1996
    Assignee: Cymer Laser Technologies
    Inventors: Palash P. Das, Donald G. Larson
  • Patent number: 5377215
    Abstract: A housing in a laser system encloses a cathode and a displaced anode and gases ionizable and reactive chemically when a voltage pulse produces a cathode-anode electrical discharge. Moving air cools the components (capacitors, thyratron and triggering circuitry) for producing the voltage pulses. The laser gas temperature is continuously regulated at a particular value whether or not there is an electrical discharge. The concentration of one of the gases in the chamber is regulated to values alternately on opposite sides of an optimal value to provide an optimal energy in each chemical reaction of the gases. The gases are recirculated as by a fan driven on a shaft by a pair of motors and are filtered during such recirculation. The shaft speed is regulated at a particular value and the motor currents are regulated to be equal. Any ozone formed in a compartment holding the high voltage terminals is purged by passing a neutral gas (nitrogen) through the compartment to the atmosphere.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: December 27, 1994
    Assignee: Cymer Laser Technologies
    Inventors: Palash P. Das, Donald G. Larson
  • Patent number: 5337330
    Abstract: An anode and a cathode in a laser are spaced in a first direction. A voltage difference between these members produces an electrical discharge which ionizes gases in the laser to react chemically and produce coherent radiation. First and second tubes made from a dielectric material are spaced in the laser in a second direction transverse (preferably perpendicular) to the first direction. The anode, the cathode and the tubes extend through the laser in a direction transverse (preferably perpendicular) to the first and second directions. The tubes are preferably at least a 99.9% pure polycrystalline aluminum oxide ceramic with traces of other metallic elements than aluminum. Bushings made from a material homogeneous (preferably identical) to the tube material are integral with the tube near the opposite tube ends. First electrical conductors extend through the tubes.
    Type: Grant
    Filed: October 9, 1992
    Date of Patent: August 9, 1994
    Assignee: Cymer Laser Technologies
    Inventor: Donald G. Larson
  • Patent number: 5048041
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: September 10, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5033055
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure an with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: July 16, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5029177
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: July 2, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5027366
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: June 25, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5023884
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member. The main insulator member is formed of ceramic material and is located intermediate to the one wall of the housing and the other electrode but is spaced from the one wall of the housing to have the main insulator member floating relative the housing structure.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: June 11, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5018161
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: May 21, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 5018162
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: May 21, 1991
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom
  • Patent number: 4959840
    Abstract: A compact excimer laser, including a housing structure having a plurality of walls forming an internal laser cavity. A gas is located within the laser cavity and with the gas capable of lasing action. A pair of spaced electrodes are located within the laser cavity and form an electrical discharge area between the electrodes for stimulating gas within the discharge area to lasing action in accordance with an electrical discharge between the electrodes. One of the pair of electrodes is located along a central position within the cavity and is grounded to the housing structure. The other of the pair of electrodes is located adjacent to but spaced from one of the walls of the housing structure and with the other electrode mounted on a main insulator member.
    Type: Grant
    Filed: January 15, 1988
    Date of Patent: September 25, 1990
    Assignee: Cymer Laser Technologies
    Inventors: Robert P. Akins, Donald G. Larson, Uday K. Sengupta, Richard L. Sandstrom