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US 2022/0012866 A1Published application
Cross layer common-unique analysis for nuisance filtering
AssigneeKLA-Tencor Corporation
InventorBjorn Brauer
Life of this patent
Estimating the term…
Abstract
Common events between layers on a semiconductor wafer are filtered. Common events should contain the majority of defects of interest. Only nuisance events that are common between layers on the semiconductor wafer remain, which reduces the nuisance rate. Defects that are common across layers can be filtered based on, for example, defect coordinates, a difference image, or defect attributes.
Claims21
A system comprising:
- a light source that generates a beam of light;
- a stage configured to hold a semiconductor wafer in a path of the beam of light;
- a detector that receives the beam of light reflected from the semiconductor wafer;
- and
- a processor in electronic communication with the detector, wherein the processor is configured to report a location of a defect of interest that is common across a first layer and a second layer of the semiconductor wafer based on difference images, and wherein the processor is further configured to:
- receive a difference image of the first layer for each defect location on the first layer, wherein the difference image of the first layer is between neighboring dies on the first layer;
- receive a difference image of the second layer for each defect location on the second layer, wherein the difference image of the second layer is between neighboring dies on the second layer;
- compare the difference image of the first layer and the difference image of the second layer;
- and
- filter defects for which the difference image of the first layer and the difference image of the second layer are similar thereby determining the defect of interest.
7 more elements
A system comprising:
- a light source that generates a beam of light;
- a stage configured to hold a semiconductor wafer in a path of the beam of light;
- a detector that receives the beam of light reflected from the semiconductor wafer;
- and
- a processor in electronic communication with the detector, wherein the processor is configured to report a location of a defect of interest that is common across a first layer and a second layer of the semiconductor wafer based on defect attributes, and wherein the processor is further configured to:
- receive a test image and a reference image for each defect location on the first layer;
- receive a test image and a reference image for each defect location on the second layer;
- calculate one or more attributes using a convolutional neural network operated by the processor, wherein the one or more attributes filter nuisance events and are based on the test image and the reference image for the first layer and the test image and the reference image for the second layer, and wherein the test image and the reference image for the first layer and the test image and the reference image for the second layer are used as channels;
- and
- filter nuisance events with the one or more attributes thereby determining the defect of interest.
7 more elements
A method comprising:
- performing a hot scan of a semiconductor wafer using a wafer inspection system;
- receiving, at a processor, a difference image of a first layer for each defect location on the first layer, wherein the difference image of the first layer is between neighboring dies on the first layer;
- receiving, at the processor, a difference image of a second layer for each defect location on the second layer, wherein the difference image of the second layer is between neighboring dies on the second layer;
- comparing, using the processor, the difference image of the first layer and the difference image of the second layer;
- filtering, using the processor, defects for which the difference image of the first layer and the difference image of the second layer are similar thereby determining the defects of interest;
- and
- reporting, using the processor, a location of a defect of interest on the semiconductor wafer that is common across a first layer and a second layer of the semiconductor wafer based on difference images.
4 more elements
A method comprising:
- performing a hot scan of a semiconductor wafer using a wafer inspection system;
- receiving, at a processor, a test image and a reference image for each defect location on a first layer;
- receiving, at the processor, a test image and a reference image for each defect location on a second layer;
- calculating, using the processor, one or more attributes using a convolutional neural network operated by the processor, wherein the one or more attributes filter nuisance events and are based on the test image and the reference image for the first layer and the test image and the reference image for the second layer, and wherein the test image and the reference image for the first layer and the test image and the reference image for the second layer are used as channels;
- filtering, using the processor, nuisance events with the one or more attributes thereby determining the defect of interest;
- and
- reporting, using the processor, a location of a defect of interest on the semiconductor wafer that is common across a first layer and a second layer of the semiconductor wafer based on defect attributes.
4 more elements
Dependencies are inferred from the claim text.