Patents by Inventor Arthur M. Howald

Arthur M. Howald 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: 6400458
    Abstract: A method for monitoring a device fabrication process. The method includes etching into a wafer disposed inside a chamber and detecting the intensity of a portion of a light reflected from a surface of the wafer and further scattered at a scattering inside surface of the chamber.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: June 4, 2002
    Assignee: Lam Research Corporation
    Inventor: Arthur M. Howald
  • Patent number: 6265831
    Abstract: A tendency for a discontinuity to occur in the amount of power reflected back to an r.f. bias source of a vacuum plasma processor is overcome by controlling the r.f. bias source output power so the power delivered to plasma in a vacuum processing chamber remains substantially constant. The r.f bias source output power is changed much faster than changes in capacitors of a matching network connecting the r.f. bias power source to an electrode of a workpiece holder processor. A capacitive impedance component of the plasma is determined by optically measuring the thickness of a plasma sheath in the chamber.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: July 24, 2001
    Assignee: Lam Research Corporation
    Inventors: Arthur M. Howald, John P. Holland, Christopher Olson
  • Patent number: 6259334
    Abstract: Disclosed are methods and devices for tuning an impedance matching network to a tune point where power reflection is at a minimum. The impedance matching network is coupled between an rf generator and a load to transmit rf power to the load. The impedance matching network includes a set of variable impedance elements. The method includes measuring a network impedance value of the impedance matching network including the load at current values of the variable impedance elements. The method further includes computing directions (i.e., increasing or decreasing) and relative rates of change for the variable impedance element values in response to the network impedance of the network such that the directions and relative rates of change for the variable impedance elements are adapted to change the reflected power in the direction of the most rapid decrease in reflected power.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: July 10, 2001
    Assignee: Lam Research Corporation
    Inventor: Arthur M. Howald
  • Patent number: 6125025
    Abstract: A glass workpiece processed in a vacuum plasma processing chamber is dechucked from a monopolar electrostatic chuck by gradually reducing the chucking voltage during processing while maintaining the voltage high enough to clamp the workpiece. The chucking voltage during processing is controlled in response to flow rate of a heat transfer fluid flowing to the chuck to maintain the chucking force and the flow rate approximately constant. A reverse polarity voltage applied to the chuck at the end of processing assists in dechucking. The workpiece temperature is maintained at a high value at the end of processing to assisting in dechucking. Peak current flowing through the chuck during workpiece lifting from the chuck controls the amplitude and/or duration of the reverse polarity voltage during the next dechucking operation. An inert plasma in the chamber removes residual charge from the workpiece after workpiece lifting from the chuck.
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: September 26, 2000
    Assignee: LAM Research Corporation
    Inventors: Arthur M. Howald, John P. Holland
  • Patent number: 6074516
    Abstract: A window of a plasma processing chamber. The window includes a first dielectric portion having a first electrical thickness and a first resistivity to an etching plasma that is formed within the plasma processing chamber. There is further included a second dielectric portion disposed within the first dielectric portion. The second dielectric portion has a second electrical thickness that is less than the first electrical thickness. The second dielectric portion is formed of a substantially transparent material and has a second resistivity to the etching plasma. The second resistivity is higher than the first resistivity.
    Type: Grant
    Filed: June 23, 1998
    Date of Patent: June 13, 2000
    Assignee: Lam Research Corporation
    Inventors: Arthur M. Howald, Anthony L. Chen, Alan M. Schoepp
  • Patent number: 4186508
    Abstract: A line guide for a fishing rod having a circular laminate (14) of resin-impregnated graphite fibers and a linear foot laminate (13) of resin-impregnated graphite fibers. The foot is attached to the circular laminate by winding some of the fibers (14) of the circular laminate underlying the foot and others (14') overlying the foot, and then heat-curing the assembly to produce a monolithic line guide and foot structure (12).
    Type: Grant
    Filed: November 14, 1978
    Date of Patent: February 5, 1980
    Assignee: Shakespeare Company
    Inventor: Arthur M. Howald