Surface inspection system
AssigneeOnto Innovation Inc.
InventorsJian Ding, Ju Jin
Life of this patent
Estimating the term…
Abstract
A surface inspection system can be provided with a laser spot size or a laser line width that is selectable based on a measurable aspect of the objects under test that project upward or downward from a surface under test. The larger laser spot size or line width can be selected to cover a larger area of the surface under test at a time, which can increase scanning speed over the surface under test and enhance system measurement throughput.
Claims20
An apparatus to measure a characteristic of a surface feature on a substrate with improved speed, comprising:
- a light source to emit an interrogating beam onto a surface of the substrate comprising at least one surface feature, wherein the interrogating beam has a beam width selected to be equal to or greater than a measurable dimension of the at least one surface feature, wherein the interrogating beam is configured to simultaneously interact with a plurality of spatially distinct portions of the at least one surface feature at each of a plurality of sample positions to form a plurality of reflections, each reflection being derived from a different spatial portion of the interrogating beam;
- a sensor to capture the plurality of reflections at each of the plurality of sample positions to generate a corresponding captured image for each sample position;
- and
- one or more processors configured to analyze the captured images from the plurality of sample positions to determine a measurable characteristic of the at least one surface feature.
A method for determining a characteristic of a surface feature on a surface of a substrate, the method comprising:
- shining the surface with at least one light source, wherein the at least one light source emits an interrogating beam with a beam width selected to be equal to or greater than a measurable dimension of the surface feature that simultaneously interacts with a plurality of spatially distinct portions of the surface feature at each of a plurality of sample positions to form a plurality of reflections, wherein each reflection is derived from a different spatial portion of the interrogating beam;
- capturing the plurality of reflections to generate a plurality of captured images, wherein each captured image is derived from a unique sample position relative to the interrogating beam;
- and
- processing at least a portion of the plurality of captured images to determine a measurable characteristic of the surface feature.
A non-transitory computer-readable medium containing instructions that, when executed by one or more processors of a machine, cause the machine to perform operations comprising:
- moving at least one light source with respect to a surface of a substrate, wherein the at least one light source emits an interrogating beam with a beam width selected to be equal to or greater than a measurable dimension of a surface feature that simultaneously interacts with a plurality of spatially distinct portions of the surface feature on the surface to form a plurality of reflections, and wherein each reflection is derived from a different spatial portion of the interrogating beam;
- capturing the plurality of reflections to generate a plurality of captured images, wherein each captured image is derived from a unique sample position relative to the interrogating beam;
- and
- processing at least a portion of the plurality of captured images to determine a measurable characteristic of the surface feature.
Dependencies are inferred from the claim text.