Back to results
US 10,656,098 B2Granted
Wafer defect inspection and review systems
AssigneeKLA-Tencor Corporation
InventorShiyu Zhang
Life of this patent
Estimating the term…
Abstract
Imaging objectives and inspection systems equipped with such imaging objectives are disclosed. The imaging objective may include a front objective configured to produce a diffraction limited intermediate image. The imaging objective may also include a relay configured to receive the intermediate image produced by the front objective. The relay may include three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane.
Claims22
An imaging objective, comprising:
- a front objective configured to produce an intermediate image of a portion of a semiconductor wafer disposed on a sample holder, wherein the intermediate image is formed from illumination from a laser-induced plasma source reflected from the portion of the semiconductor wafer disposed on the sample holder, wherein the front objective comprises:
- a lens with a plano side serving as a reflecting surface;
- a meniscus lens;
- a concave mirror;
- and
- a series of refractive fused silica and calcium fluoride lenses;
- and
- a relay configured to receive the intermediate image produced by the front objective, the relay comprising three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane.
5 more elements
An inspection system, comprising:
- an illumination source, wherein the illumination source includes a laser-induced plasma source;
- a sample holder configured to hold a semiconductor wafer;
- a detector positioned at a fixed location within the inspection system;
- and
- an imaging objective configured to image the semiconductor wafer onto the detector, wherein the imaging objective comprises a front objective and a relay,
- wherein the front objective is configured to produce a diffraction limited intermediate image of a portion of the semiconductor wafer,
- wherein the relay is configured to receive the intermediate image produced by the front objective, the relay comprising three spherical mirrors positioned to deliver a projection of the intermediate image to the detector positioned at the fixed location.
4 more elements
An imaging objective, comprising:
- a front objective configured to produce a diffraction-limited intermediate image of a portion of a semiconductor wafer disposed on a sample holder, wherein the intermediate image is formed from illumination from a laser-induced plasma source reflected from the portion of the semiconductor wafer disposed on the sample holder;
- and
- a relay configured to receive the intermediate image produced by the front objective, the relay comprising three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane, the three spherical mirrors being all reflective mirrors with substantially no obscuration, the three spherical mirrors being further configured to have different curvatures with respect to each other.
An imaging objective, comprising:
- a front objective configured to produce an intermediate image of a portion of a semiconductor wafer disposed on a sample holder, wherein the intermediate image is formed from illumination from a laser-induced plasma source reflected from the portion of the semiconductor wafer disposed on the sample holder;
- and
- a relay configured to receive the intermediate image produced by the front objective, the relay comprising three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane, wherein the three spherical mirrors are moveable at least axially or vertically while still maintaining the projection of the intermediate image to the fixed image plane.
Dependencies are inferred from the claim text.