Evaluation of surface and subsurface characteristics of a sample
AssigneeTherma-Wave, Inc.
InventorsAllan Rosencwaig, Jon Opsal
Life of this patent
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Abstract
A method and apparatus is disclosed for evaluating surface and subsurface features in a sample by detecting scattering of a probe beam. More particularly, the subject invention relates to the detection of thermal and/or plasma waves through the phenomenon of optical scattering. The apparatus includes a periodic excitation source for supplying energy to the surface of the sample to generate thermal and/or plasma waves. A radiation probe is directed to the surface of the sample within the area that is being periodically excited and in a manner that the probe beam is scattered from the excited area. Variations of the intensity of the scattered probe beam are detected and processed to evaluate surface and subsurface characteristics of the sample.
Claims12
An apparatus for evaluating surface and subsurface features in a sample comprising:
- a periodic excitation source for supplying energy to the surface of the sample;
- a radiation probe beam;
- means for directing said probe beam within at least a portion of the area on the surface of the sample which is being periodically excited such that a portion of said probe beam is scattered from the periodically excited area;
- means for monitoring intensity changes of the scattered probe beam radiation and generating an output signal corresponding thereto;
- and
- means for processing the output signal corresponding to the measured intensity changes of the scattered probe beam to evaluate the sample.
A method for evaluating surface and subsurface features in a sample comprising
- supplying periodic energy to the surface of the sample;
- directing a radiation probe onto at least a portion of the area on the surface of the sample which is being periodically excited, such that a portion of the probe beam is scattered from the periodically excited area;
- monitoring intensity changes of the scattered probe beam radiation;
- generating an output signal corresponding to the measured intensity changes;
- and
- processing the output signal corresponding to the measured intensity changes of the scattered probe beam to evaluate the sample.
Dependencies are inferred from the claim text.