Back to results
US 8,896,832 B2Granted
Discrete polarization scatterometry
AssigneeKLA-Tencor Corporation
InventorsAndrew V. Hill, Amnon Manassen, Daniel Kandel, Vladimir Levinski, Joel Seligson, Alexander Svizher, David Y. Wang, Lawrence D. Rotter, Johannes D. de Veer
Life of this patent
Estimating the term…
Abstract
Systems and methods for discrete polarization scatterometry are provided.
Claims35
An optical subsystem of a scatterometer, comprising:
- one or more light sources configured to produce light having different polarizations;
- a polarizing beam splitter configured to separate the light into two different light beams having orthogonal and mutually exclusive polarizations;
- two or more first optical elements configured to direct the two different light beams to a wafer;
- one or more second optical elements configured to control which one of the two different light beams illuminates the wafer during measurements;
- and
- a detection subsystem configured to separately detect two different scattered light beams resulting from illumination of the wafer with only the one of the two different light beams and to separately generate output responsive to the two different scattered light beams, wherein the two different scattered light beams have orthogonal and mutually exclusive polarizations, and wherein all optical surfaces of the optical subsystem used for the measurements are stationary during the measurements.
3 more elements
A scatterometer, comprising:
- one or more light sources configured to produce light having different polarizations;
- a polarizing beam splitter configured to separate the light into two different light beams having orthogonal and mutually exclusive polarizations;
- two or more first optical elements configured to direct the two different light beams to a wafer;
- one or more second optical elements configured to control which one of the two different light beams illuminates the wafer during measurements;
- a detection subsystem configured to separately detect two different scattered light beams resulting from illumination of the wafer with only the one of the two different light beams and to separately generate output responsive to the two different scattered light beams, wherein the two different scattered light beams have orthogonal and mutually exclusive polarizations, and wherein all optical surfaces used for the measurements are stationary during the measurements;
- and
- a computer subsystem configured to determine one or more characteristics of features formed on the wafer using the output.
4 more elements
A scatterometry method, comprising:
- producing light having different polarizations;
- separating the light into two different light beams having orthogonal and mutually exclusive polarizations;
- directing the two different light beams to a wafer;
- controlling which one of the two different light beams illuminates the wafer during measurements;
- separately detecting two different scattered light beams resulting from illuminating the wafer with only the one of the two different light beams;
- separately generating output responsive to the two different scattered light beams, wherein the two different scattered light beams have orthogonal and mutually exclusive polarizations, and wherein all optical surfaces used for steps of the method are stationary during the measurements;
- and
- determining a characteristic of features formed on the wafer using the output.
5 more elements
Dependencies are inferred from the claim text.