PATENT CLAIM ANALYSIS

Application Number: 15761664
Application Type: Utility
Filing Date: 2018-03
Publication Date: 2018-12
Patent Classification: ["356", "369000"]

Abstract:
A method for measuring thickness variations in a first layer of a semiconductor structure includes: —acquiring an image of at least one zone of the surface of the structure —processing the acquired image so as to determine a map of the thickness variations of the first layer, and comparing the intensity of each pixel of the image with a predetermined calibration curve, the calibration curve being determined for a given thickness of a second layer of the, structure, and —measuring the thickness of the second layer in the at least one zone, —if the measured thickness is different from the thickness of the second layer considered in the calibration curve, and using a correction curve to determine a corrected map of thickness variations of the first layer.

Claim (Index 11):
A system for measuring thickness variations in a first layer of a multilayer semiconductor structure, comprising:\n a device for illuminating the structure, adapted for emitting a quasi-monochromatic light flux towards the surface of the structure, wherein the wavelength of the light flux corresponds to a minimum of the sensitivity of the reflectivity with respect to a second layer of the structure different from the first layer, the sensitivity of the reflectivity with respect to a layer being equal to the ratio between:\n (i) the difference between the reflectivities of two multilayer structures for which the considered layer has a given thickness difference, and \n (ii) the given thickness difference, the thicknesses of the other layers being identical in both multilayer structures, \n an image acquisition system laid out so as to acquire at least one image of a zone of the surface of the structure by reflection of the quasi-monochromatic light flux, a device for measuring, in particular by ellipsometry, the thickness of the second layer to be measured in the at least one zone of the surface of the structure, a memory wherein a calibration curve defining a relationship between intensity of a pixel in the acquired image and a local thickness of the first layer is stored, the calibration curve being determined for a given thickness of the second layer, a processing system configured for, from the at least one acquired image, determining from the intensity variations of the light reflected by the surface, a map of the variations of the thickness of the first layer by comparing the intensity of each pixel of the acquired image with the calibration curve, a computation system configured to receive thickness measurement data from the measuring device and for, if the measured thickness is different from the thickness of the second layer considered in the calibration curve, applying a correction curve to the map of the thickness variations, wherein the correction curve defines, for the measured thickness of the second layer, a relationship between a thickness of the first layer and a correction factor to apply to the map of the thickness variations of the first layer, so as to determine a corrected map of thickness variations of the first layer.

Metadata:
- Claim Count in Document: 44.0
- Percentile: 90.0
- Lexical Diversity: 2.41071
- Patent Class: 356.0
- Transitional Phrase Type: open
- Component Type: 1
- Foreign Priority: True
- Related Applications: ['14442081', '11819838', '15401831', '14909933', '15223424']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.6783372490265908
- 35 USC 102 Novelty (BERT): 0.5313327974511863
- Combined Prediction Score: 0.6636368038690503
- Mean Citation Score: 211.63471
- Max Citation Score: 369.191
- Similarity Product: 321.98300036156184

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

Dataset: test