Systems and methods for defect detection using image reconstruction

An inspection system, comprising:

• an illumination sub-system, comprising:
• an illumination source configured to generate a beam of illumination;
• and
• a set of illumination optics to direct the beam of illumination to a sample;
• a collection sub-system, comprising:
• a set of collection optics to collect illumination emanating from the sample;
• and
• a detector configured to receive the collected illumination from the sample;
• and
• a controller communicatively coupled to the detector, the controller including a memory device and one or more processors configured to execute program instructions configured to cause the one or more processors to:
• acquire a test image of the sample;
• detect one or more defects on the sample based on the test image;
• generate one or more patch images associated with the one or more detected defects on the sample;
• estimating a point spread function of the inspection system as a transform of a combination of an illumination aperture and a collection aperture of the inspection system;
• reconstruct the one or more patch images, based on the estimated point spread function, to enhance the resolution of the one or more patch images;
• and
• classify the one or more defects based on the one or more reconstructed patch images.

A multi-mode inspection system, comprising:

• an illumination sub-system, comprising:
• an illumination source configured to generate two or more modes of illumination;
• and
• a set of illumination optics to sequentially direct the two or more modes of illumination to a sample;
• a collection sub-system, comprising:
• a set of collection optics to collect illumination emanating from the sample, wherein the set of collection optics includes an adjustable collection aperture, wherein the adjustable collection aperture is configured to generate two or more collection modes, wherein the illumination sub-system includes two or more system modes formed from the two or more modes of illumination and the two or more collection modes;
• and
• a detector configured to receive the collected illumination from the sample;
• and
• a controller communicatively coupled to the detector, the controller including a memory device and one or more processors configured to execute program instructions configured to cause the one or more processors to:
• acquire two or more test images of the sample based on the two or more system modes;
• estimate a point spread function of the inspection system as a transform of a combination of an illumination aperture and a collection aperture of the inspection system;
• reconstruct the two or more test images, based on the estimated point spread function, to enhance the resolution of the two or more test images based on the estimated point spread function;
• and
• identify one or more defects on the sample based on the two or more reconstructed test images.

An inspection system, comprising:

• an illumination sub-system, comprising:
• an illumination source configured to generate a beam of illumination;
• and
• a set of illumination optics to direct the beam of illumination to a sample;
• a collection sub-system, comprising:
• a set of collection optics to collect illumination emanating from the sample;
• and
• a detector configured to receive the collected illumination from the sample;
• and
• a controller communicatively coupled to the detector, the controller including a memory device and one or more processors configured to execute program instructions configured to cause the one or more processors to:
• configure a defect detection recipe, wherein configuring the defect detection recipe comprises:
• acquiring a configuration image of the sample;
• estimating a point spread function of the inspection system as a transform of a combination of an illumination aperture and a collection aperture of the inspection system;
• and
• reconstructing the configuration image of the sample, based on the estimated point spread function, to enhance the resolution of the configuration image;
• and
• detect one or more defects on the sample based on the defect detection recipe.