Diversifying sem measurement scheme for improved accuracy
AssigneeASML Netherlands B.V.
InventorsAlexandru ONOSE, Tiago BOTARI, Anagnostis TSIATMAS, Markus Gerardus Martinus Maria VAN KRAAIJ
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Abstract
A charged particle beam inspection method includes measuring a sample under multiple different signal acquisition modalities. Each modality may comprise a different set of inspection parameters that may be optimized for different purposes such as high resolution or high acquisition speed. Measurements from the different signal acquisition modalities may be combined to form a synthesized image using a deconvolution or other optimization task. The synthesized image may achieve superior resolution at higher throughput than is achievable with a single high-resolution or high-speed scan.
Claims20
A non-transitory computer-readable medium that stores a set of instructions that is executable by at least one processor of a charged particle beam apparatus to cause the charged particle beam apparatus to perform operations comprising:
- measuring a first region of a sample under a first signal acquisition modality to obtain a first signal profile;
- measuring a second region of the sample under a second signal acquisition modality to obtain a second signal profile, the second signal acquisition modality being different from the first signal acquisition modality in an inspection parameter of the charged particle beam apparatus;
- and
- generating, using an optimization task, an inspection image based on a synthesis of the first signal profile and the second signal profile.
A charged particle beam apparatus, comprising:
- a charged particle beam source configured to generate a beam of primary charged particles;
- a charged particle optical system configured to direct the beam of primary charged particles at a sample surface to inspect the sample surface;
- a charged particle detector configured to detect charged particles returned from the sample surface;
- and
- a controller comprising one or more processors and configured to cause the charged particle beam apparatus to perform operations comprising:
- measuring a first region of a sample under a first signal acquisition modality to obtain a first signal profile;
- measuring a second region of the sample under a second signal acquisition modality to obtain a second signal profile, the second signal acquisition modality being different from the first signal acquisition modality in an inspection parameter of the charged particle beam apparatus;
- and
- generating, using an optimization task, an inspection image based on a synthesis of the first signal profile and the second signal profile.
Dependencies are inferred from the claim text.