Claims
- 1. A method for inspecting a specimen, comprising the steps of:
illuminating said specimen using broadband brightfield illumination and darkfield illumination; sensing both broadband brightfield illumination and darkfield illumination of said specimen with a single sensor; and detecting defects for said specimen using combined data from the broadband brightfield illumination and the darkfield illumination from said illuminating step.
- 2. A system for inspecting a specimen, said system comprising:
a broadband brightfield illuminator; a plurality of lasers for providing darkfield illumination of said specimen; a fourier filtering device for removing repeating patterns from images produced by said broadband brightfield illuminator and said plurality of lasers; and a sensor for sensing data received from said fourier filtering device.
- 3. The system of claim 2, wherein sensor comprises a time delay integration sensor.
- 4. The system of claim 2, wherein said plurality of lasers have a predetermined azimuth offset from one another and energy emitted from said plurality of lasers is angularly adjustable.
- 5. A system for adjusting a beam from a laser to provide illumination of a specimen to achieve a desired position and ellipticity of said beam on said specimen, comprising:
a rotating cylindrical lens; and an adjustable mirror; wherein said beam passes through said rotating cylindrical lens and off said adjustable mirror onto said specimen.
- 6. The system of claim 5, further comprising a pixel size changer disposed between said rotating cylindrical lens and said adjustable mirror.
- 7. The system of claim 5 wherein adjustment of said adjustable mirror requires modification of said cylindrical lens to provide compensation and elliptically orient said beam.
- 8. A method for adjusting a beam from a laser to provide illumination of a specimen to achieve a desired position and ellipticity of said beam on said specimen, said beam being redirected by a rotating cylindrical lens and reflected off an adjustable mirror having a first orientation, comprising the steps of:
adjusting said first orientation of said adjustable mirror to a second orientation; and modifying the position of the rotating cylindrical lens.
- 9. The method of claim 8, wherein said adjusting step comprises translating said adjustable mirror in a vertical direction, said vertical direction being normal to said specimen.
- 10. The method of claim 9, wherein said modifying step comprises:
rotating the cylindrical lens to orient the beam; and moving said cylindrical lens to shape said beam into an acceptable ellipse.
- 11. A light level control system for controlling a laser beam used to inspect a specimen into a plurality of equal intensity beams, comprising:
a first polarizer for receiving and polarizing the laser beam; a second polarizer for receiving and polarizing the beam received from said first polarizer; a filter for absorbing a portion of the beam transmitted by said second polarizer; and a polarizing beamsplitter for dividing the beam received from said filter into a plurality of equal intensity beams.
- 12. The system of claim 11, further comprising a reflector and polarizer for at least one equal intensity beam received from said polarizing beamsplitter.
- 13. The system of claim 11, further comprising a laser power sensor for measuring polarizing beamsplitter transmission and controlling system light level.
- 14. An apparatus for inspecting a specimen, comprising:
a brightfield illumination arrangement; a darkfield illumination arrangement; and a combined brightfield and darkfield advantageous beamsplitter arrangement, said brightfield and darkfield advantageous beamsplitter arrangement providing beamsplitting capability for said brightfield illumination arrangement and relatively unobstructed performance for said darkfield illumination arrangement.
- 15. The system of claim 14, wherein said combined brightfield and darkfield advantageous beamsplitter arrangement comprises a removable beamsplitter which may be replaced by a blank such as a piece of glass.
- 16. The system of claim 14, wherein said combined brightfield and darkfield advantageous beamsplitter arrangement comprises transmitting light in said brightfield illumination arrangement in a spectrum in a first color spectrum, and transmitting light in said darkfield illumination arrangement in a second color spectrum, said first and second color spectrums having different frequencies.
Parent Case Info
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 08/884,467, entitled “Optical Inspection of a Specimen Using Multi-Channel Responses from the Specimen,” filed on Jun. 27, 1997, which is a continuation of U.S. patent application Ser. No. 08/489,019, filed on Jun. 6, 1995, now abandoned.
Continuations (2)
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Number |
Date |
Country |
Parent |
08991927 |
Dec 1997 |
US |
Child |
09907295 |
Jul 2001 |
US |
Parent |
08489019 |
Jun 1995 |
US |
Child |
08884467 |
Jun 1997 |
US |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
08884467 |
Jun 1997 |
US |
Child |
08991927 |
Dec 1997 |
US |