Robert C Frazier

Address:

1504 Harold St, Houston, TX 77006

Phone:

7135240828

VIN:

JM1NC25F880139679

Make:

MAZDA

Model:

MX-5 MIATA

Year:

2008

Address:

1504 Harold St, Houston, TX 77006

VIN:

1M5BA202571E16764

Make:

Lincoln

Model:

Continental 4dr Sedan Si

Year:

2007

US Patent:

44866461, Dec 4, 1984

Filed:

Apr 1, 1982

Appl. No.:

6/364173

Inventors:

Robert F. Frazier - San Francisco CA

International Classification:

B23K 910

US Classification:

2191301

Abstract:

Apparatus and a method for generating a ramp voltage for use as a control signal in the electrode circuit of an arc welder. The generator includes an integrator whose input is coupled to a current generator by a switching network controlled by switch logic responsive to the output voltage of the integrator itself. The current generator supplies negative and positive currents alternately to the input of the integrator as a function of the actuation of the switching network so that a ramp voltage characteristic can be obtained in which the ramp voltage, once it reaches a maximum value, will fluctuate at a frequency above 20 kHz between upper and lower limits on either side of a mean value such that the mean value will be constant over time. The output voltage of the integrator is compared with an adjustable reference voltage and the result of the comparison is to provide signals applied to the switching network to ultimately cause negative and positive currents from the current generator to be applied to the integrator at a relatively high frequency, such as a frequency of 50 kHz. One of the signals is amplified to decrease the response time of switching from a first current to the second current and bias means is provided to decrease the response time in switching back from the second current to the first current.

US Patent:

55693563, Oct 29, 1996

Filed:

May 19, 1995

Appl. No.:

8/445292

Inventors:

Eric H. Lenz - San Jose CA
Michael L. Calvisi - Union City CA
Ivo A. Miller - San Jose CA
Robert A. Frazier - Fremont CA

Assignee:

LAM Research Corporation - Fremont CA

International Classification:

H01L 2100

US Classification:

1566431

Abstract:

An electrode clamping assembly for a plasma reaction chamber wherein processing of a single wafer can be carried out. The electrode assembly includes a support member, an electrode such as a silicon showerhead electrode in the form of a disk having uniform thickness and a clamping ring which provides a resilient clamping force pressing against the showerhead electrode. The clamping member can be a ring of elastically deformable material and the clamping member can be tightened by a plurality of elastic spaced-apart bolts such that the clamping member is compressed and provides the resilient clamping force throughout temperature cycling of the electrode assembly during wafer processing. Heat conduction between the showerhead electrode and the support member can be improved by supplying pressurized process gas to a gap therebetween. The clamping member also provides plasma confinement in an area between the electrode and the wafer being processed.