Jeffrey T Fanton

US Patent:

6411385, Jun 25, 2002

Filed:

Jun 21, 2001

Appl. No.:

09/886514

Inventors:

David E. Aspnes - Apex NC
Jon Opsal - Livermore CA
Jeffrey T. Fanton - Los Altos CA

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01J 400

US Classification:

356369

Abstract:

An optical measurement system for evaluating a reference sample that has at least a partially known composition. The optical measurement system includes a reference ellipsometer and at least one non-contact optical measurement device. The reference ellipsometer includes a light generator, an analyzer and a detector. The light generator generates a beam of quasi-monochromatic light having a known wavelength and a known polarization for interacting with the reference sample. The beam is directed at a non-normal angle of incidence relative to the reference sample to interact with the reference sample. The analyzer creates interference between the S and P polarized components in the light beam after the light beam has interacted with reference sample. The detector measures the intensity of the light beam after it has passed through the analyzer. A processor determines the polarization state of the light beam entering the analyzer from the intensity measured by the detector, and determines an optical property of the reference sample based upon the determined polarization state, the known wavelength of light from the light generator and the composition of the reference sample.

US Patent:

6515746, Feb 4, 2003

Filed:

May 3, 2002

Appl. No.:

10/138984

Inventors:

Jon Opsal - Livermore CA
Jeffrey T. Fanton - Los Altos CA
Craig Uhrich - Redwood City CA

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01J 400

US Classification:

356369, 356630

Abstract:

An optical measurement system for evaluating a reference sample that has at least a partially known composition. The optical measurement system includes a reference ellipsometer and at least one non-contact optical measurement device. The reference ellipsometer includes a light generator, an analyzer and a detector. The light generator generates a beam of quasi-monochromatic light having a known wavelength and a known polarization for interacting with the reference sample. The beam is directed at a non-normal angle of incidence relative to the reference sample to interact with the reference sample. The analyzer creates interference between the S and P polarized components in the light beam after the light beam has interacted with reference sample. The detector measures the intensity of the light beam after it has passed through the analyzer. A processor determines the polarization state of the light beam entering the analyzer from the intensity measured by the detector, and determines an optical property of the reference sample based upon the determined polarization state, the known wavelength of light from the light generator and the composition of the reference sample.

US Patent:

6707056, Mar 16, 2004

Filed:

Apr 26, 2002

Appl. No.:

10/132959

Inventors:

Jeffrey T. Fanton - Los Altos CA
Craig Uhrich - Redwood City CA

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01N 2100

US Classification:

25055944, 3562372

Abstract:

A method for operating an optical measurement system is disclosed which permits measurements to be made more uniformly in regions close the edge of a wafer. The optical measurement system includes a probe beam which is focused to an elliptically shaped spot on the surface of the wafer. Improved measurements near the wafers edge are obtained by rotating the wafer with respect to the measurement spot to insure that the short axis of the ellipse is perpendicular to the wafer edge.

US Patent:

6744850, Jun 1, 2004

Filed:

Oct 24, 2001

Appl. No.:

10/053373

Inventors:

Jeffrey T. Fanton - Los Altos CA
Craig Uhrich - Redwood City CA
Louis N. Koppel - San Jose CA

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01T 136

US Classification:

378 83, 378 82, 378 70

Abstract:

An x-ray reflectometry system for measuring thin film samples. The system includes an adjustable x-ray source, such that characteristics of an x-ray probe beam output by the x-ray source can be adjusted to improve the resolution of the measurement system. The x-ray probe beam can also be modified to increase the speed of evaluating the thin film sample, for situations where some degree of resolution can be sacrificed. In addition, or alternatively, the system can also provide an adjustable detector position device which allows the position of the detector to be adjusted to increase the resolution of the system, or to reduce the time it takes to evaluate the thin film material.

US Patent:

6753962, Jun 22, 2004

Filed:

Dec 17, 2002

Appl. No.:

10/320907

Inventors:

Jon Opsal - Livermore CA
Jeffrey T. Fanton - Los Altos CA
Craig Uhrich - Redwood City CA

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01J 400

US Classification:

356369, 356630

Abstract:

An optical measurement system for evaluating a reference sample that has at least a partially known composition. The optical measurement system includes a reference ellipsometer and at least one non-contact optical measurement device. The reference ellipsometer includes a light generator, an analyzer and a detector. The light generator generates a beam of quasi-monochromatic light having a known wavelength and a known polarization for interacting with the reference sample. The beam is directed at a non-normal angle of incidence relative to the reference sample to interact with the reference sample. The analyzer creates interference between the S and P polarized components in the light beam after the light beam has interacted with reference sample. The detector measures the intensity of the light beam after it has passed through the analyzer. A processor determines the polarization state of the light beam entering the analyzer from the intensity measured by the detector, and determines an optical property of the reference sample based upon the determined polarization state, the known wavelength of light from the light generator and the composition of the reference sample.

US Patent:

6885019, Apr 26, 2005

Filed:

Jan 28, 2004

Appl. No.:

10/766125

Inventors:

Jeffrey T. Fanton - Los Altos CA, US
Craig Uhrich - Redwood City CA, US

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01N021/00

US Classification:

25055944, 2562372

Abstract:

Systems and methods for operating an optical measurement system are disclosed which permit measurements to be made more uniformly in regions close the edge of a sample, such as a wafer. An optical measurement system can include a probe beam that is focused to an elliptically shaped spot on the surface of the sample. Improved measurements near the edge of the sample can be obtained by rotating the wafer with respect to the measurement spot to ensure that the short axis of the ellipse is perpendicular to the wafer edge.

US Patent:

6934025, Aug 23, 2005

Filed:

May 5, 2004

Appl. No.:

10/839049

Inventors:

Jon Opsal - Livermore CA, US
Jeffrey T. Fanton - Los Altos CA, US
Craig Uhrich - Redwood City CA, US

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01J004/00

US Classification:

356369, 356630

Abstract:

An optical measurement system for evaluating a reference sample, having at least a partially known composition, includes a reference ellipsometer and at least one non-contact optical measurement device. The ellipsometer includes a light generator, an analyzer, and a detector. The light generator generates a beam of quasi-monochromatic light of known wavelength and polarization, which is directed at a non-normal angle of incidence relative to the reference sample. The analyzer creates interference between S and P polarized components in the beam after interaction with the sample. The detector then measures the intensity of the beam, which a processor uses to determine the polarization state of the beam and, subsequently, an optical property of the reference sample. The processor then can calibrate an optical measurement device by comparing a measured optical parameter from the optical measurement device to the determined optical property from the reference ellipsometer.

US Patent:

7054006, May 30, 2006

Filed:

Feb 19, 2004

Appl. No.:

10/782321

Inventors:

Haiming Wang - Fremont CA, US
Jeffrey T. Fanton - Los Altos CA, US
Lanhua Wei - Fremont CA, US

Assignee:

Therma-Wave, Inc. - Fremont CA

International Classification:

G01N 21/00

US Classification:

356369

Abstract:

A real-time calibration method for beam profile ellipsometry systems includes projecting an electromagnetic probe beam having a known polarization state though an objective lens onto the surface of a subject and collecting the reflected probe beam using the same objective. The reflected probe beam is then passed through a rotating compensator and analyzer before being received by a detector. A processor performs a harmonic analysis on the detector output to determine normalized Fourier coefficients. The processor uses Fourier coefficients to measure the retardation δand the azimuth angle Qof the objective lens; and uses the retardation δand the azimuth angle Qto identify the ellipsometric effects of the objective lens.