PATENT CLAIM ANALYSIS

Application Number: 15861938
Application Type: Utility
Filing Date: 2018-01
Publication Date: 2018-09
Patent Classification: ["356", "338000"]

Abstract:
Methods and systems for robust overlay error measurement based on a trained measurement model are described herein. The measurement model is trained from raw scatterometry data collected from Design of Experiments (DOE) wafers by a scatterometry based overlay metrology system. Each measurement site includes one or more metrology targets fabricated with programmed overlay variations and known process variations. Each measurement site is measured with known metrology system variations. In this manner, the measurement model is trained to separate actual overlay from process variations and metrology system variations which affect the overlay measurement. As a result, an estimate of actual overlay by the trained measurement model is robust to process variations and metrology system variations. The measurement model is trained based on scatterometry data collected from the same metrology system used to perform measurements. Thus, the measurement model is not sensitive to systematic errors, aysmmetries, etc.

Claim (Index 33):
The method of  claim 25 , wherein the estimating of the value of actual overlay involves:\n illuminating each of the plurality of overlay metrology targets at a plurality of different illumination wavelengths; collecting an amount of light scattered from each of the plurality of overlay metrology targets in response to each different illumination wavelength, wherein the amount of light includes +1 and \u22121 diffraction orders; detecting an image of the amount of light collected from each overlay metrology target at each different illumination wavelength onto a plurality of pixels of the optical detector of the scatterometry based metrology system; estimating a first value of actual overlay based on differences between the +1 and \u22121 diffraction orders for each different illumination wavelength; determining a peak value of actual overlay from the first values of actual overlay associated with the different illumination wavelengths; determining a difference in wavelength from the wavelength associated with the peak value that minimizes within-wafer overlay variation; and estimating a second value of actual overlay based on the measurement of overlay at the distance from the peak value.

Metadata:
- Claim Count in Document: 5.0
- Percentile: 86.0
- Lexical Diversity: 2.19178
- Patent Class: 356.0
- Transitional Phrase Type: none
- Component Type: 0
- Foreign Priority: False
- Related Applications: ['14880077', '14704840', '14924308', '14790793', '15671661']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.7945945748150788
- 35 USC 102 Novelty (BERT): 0.5534039598931205
- Combined Prediction Score: 0.770475513322883
- Mean Citation Score: 412.203012
- Max Citation Score: 451.2528
- Similarity Product: 323.2671360774994

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

Dataset: test