PATENT CLAIM ANALYSIS

Application Number: 15967861
Application Type: Utility
Filing Date: 2018-05
Publication Date: 2018-11
Patent Classification: ["355", "018000"]

Abstract:
An overlay metrology target (600, 900, 1000) contains a plurality of overlay gratings (932-935) formed by lithography. First diffraction signals (740(1)) are obtained from the target, and first asymmetry values (As) for the target structures are derived. Second diffraction signals (740(2)) are obtained from the target, and second asymmetry values (As′) are derived. The first and second diffraction signals are obtained using different capture conditions and/or different designs of target structures and/or bias values. The first asymmetry signals and the second asymmetry signals are used to solve equations and obtain a measurement of overlay error. The calculation of overlay error makes no assumption whether asymmetry in a given target structure results from overlay in the first direction, in a second direction or in both directions. With a suitable bias scheme the method allows overlay and other asymmetry-related properties to be measured accurately, even in the presence of two-dimensional overlay structure.

Claim (Index 84):
The metrology target of  claim 81 , wherein five or more of the target structures are arranged in a closed ring.

Metadata:
- Claim Count in Document: 32.0
- Percentile: 93.0
- Lexical Diversity: 2.18072
- Patent Class: 355.0
- Transitional Phrase Type: none
- Component Type: 0
- Foreign Priority: True
- Related Applications: ['15834763', '15013340', '15186031', '15875156', '15032507']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.7484782420350788
- 35 USC 102 Novelty (BERT): 0.5160800033816736
- Combined Prediction Score: 0.7252384181697383
- Mean Citation Score: 291.46837000000005
- Max Citation Score: 308.44202
- Similarity Product: 141.153776603325

Labels:
- Claim Label 101: 1
- Claim Label 102: 0
- Claim Label 103: 1
- Claim Label 112: 1
- Combined Label: 0
- Label 101 Adjusted: 1

Dataset: test