Hidden defect detection and epe estimation based on the extracted 3d information from e-beam images

A method for improving a process model for a patterning process, the method comprising:

• obtaining a) a captured image of a printed pattern from an image capture device, b) a simulated image generated by the process model, and c) a combined image of the captured image and the simulated image;
• determining three-dimensional features of the printed pattern from the combined image;
• and
• improving the process model based on the determined three-dimensional features.

A computer program product comprising a non-transitory computer readable medium having instructions recorded thereon, the instructions when executed by a computer implementing a method comprising:

• obtaining a) a captured image of a printed pattern from an image capture device, and b) a simulated image of the printed pattern generated by a process model;
• generating a combined image as a weighted combination of portions of the captured image and the simulated image;
• and
• determining whether a defect exists in the printed pattern based on the combined image.

A computer program product comprising a non-transitory computer readable medium having instructions recorded thereon, the instructions when executed by a computer implementing a method comprising:

• obtaining a) a captured image of a printed pattern from an image capture device, b) a simulated image generated by the process model, and c) a combined image of the captured image and the simulated image;
• determining three-dimensional features of the printed pattern from the combined image;
• and
• improving the process model based on the determined three-dimensional features.