Breakdown analysis of geometry induced overlay and utilization of breakdown analysis for improved overlay control
Granted: December 17, 2019
Patent Number:
10509329
Systems and methods for providing improved measurements and predictions of geometry induced overlay errors are disclosed. Information regarding variations of overlay errors is obtained and analyzed to improve semiconductor processes as well as lithography patterning. In some embodiments, a cascading analysis process is utilized to breakdown the wafer geometry induced overlay into various components. The breakdown analysis may also be utilized to determine effectiveness factors for the…
Target location in semiconductor manufacturing
Granted: December 10, 2019
Patent Number:
10504802
A method of overlay control in silicon wafer manufacturing comprises firstly locating a target comprising a diffraction grating on a wafer layer; and then measuring the alignment of patterns in successive layers of the wafer. The location of the target may be done by the pupil camera rather than a vision camera by scanning the target to obtain pupil images at different locations along a first axis. The pupil images may comprise a first order diffraction pattern for each location. A…
Semiconductor metrology with information from multiple processing steps
Granted: December 10, 2019
Patent Number:
10504759
Methods and systems for measuring process induced errors in a multiple patterning semiconductor fabrication process based on measurements of a specimen and process information from one or more previous process steps employed to fabricate the specimen are presented herein. A metrology tool is employed after a number of process steps have been executed. The metrology tool measures structural parameters of interest of metrology targets on the wafer based on measured signals and process…
Wafer noise reduction by image subtraction across layers
Granted: December 10, 2019
Patent Number:
10504213
Noise reduction in a difference image of an optical inspection tool is provided by calculating a difference image across layers of a multi-layered wafer. A first wafer image of a first wafer layer and a second wafer image of a second wafer layer are used. The first wafer image and the second wafer image are at a same planar location on the multi-layered wafer, but of different layers and/or after different process steps. A first difference image is calculated between the first wafer…
Criticality analysis augmented process window qualification sampling
Granted: December 10, 2019
Patent Number:
10503078
Techniques are provided that can select defects based on criticality of design pattern as well as defect attributes for process window qualification (PWQ). Defects are sorted into categories based on process conditions and similarity of design. Shape based grouping can be performed on the random defects. Highest design based grouping scores can be assigned to the bins, which are then sorted. Particular defects can be selected from the bins. These defects may be reviewed.
Methods and apparatus for patterned wafer characterization
Granted: December 10, 2019
Patent Number:
10502694
Disclosed are apparatus and methods for characterizing a plurality of structures of interest on a semiconductor wafer. A plurality of spectra signals are measured from a particular structure of interest at a plurality of azimuth angles from one or more sensors of a metrology system. A difference spectrum is determined based on the spectra signals obtained for the azimuth angles. A quality indication of the particular structure of interest is determined and reported based on analyzing the…
Automated metrology system selection
Granted: December 10, 2019
Patent Number:
10502692
Methods and systems for evaluating and ranking the measurement efficacy of multiple sets of measurement system combinations and recipes for a particular metrology application are presented herein. Measurement efficacy is based on estimates of measurement precision, measurement accuracy, correlation to a reference measurement, measurement time, or any combination thereof. The automated the selection of measurement system combinations and recipes reduces time to measurement and improves…
Model-based single parameter measurement
Granted: December 10, 2019
Patent Number:
10502549
Methods and systems for building and using a parameter isolation model to isolate measurement signal information associated with a parameter of interest from measurement signal information associated with incidental model parameters are presented herein. The parameter isolation model is trained by mapping measurement signals associated with a first set of instances of a metrology target having known values of a plurality of incidental model parameters and known values of a parameter of…
System and method for reducing the bandwidth of a laser and an inspection system and method using a laser
Granted: December 3, 2019
Patent Number:
10495582
A DUV laser includes an optical bandwidth filtering device, such as etalon, which is disposed outside of the laser oscillator cavity of the fundamental laser, and which directs one range of wavelengths into one portion of a frequency conversion chain and another range of wavelengths into another portion of the frequency conversion train, thereby reducing the bandwidth of the DUV laser output while maintaining high conversion efficiency in the frequency conversion chain.
Metrology recipe generation using predicted metrology images
Granted: December 3, 2019
Patent Number:
10496781
A metrology system includes a controller communicatively coupled to a metrology tool. The controller may generate a three-dimensional model of a sample, generate a predicted metrology image corresponding to a predicted analysis of the sample with the metrology tool based on the three-dimensional model, evaluate two or more candidate metrology recipes for extracting the metrology measurement from the one or more predicted metrology images, select, based on one or more selection metrics, a…
System and method for compensation of illumination beam misalignment
Granted: December 3, 2019
Patent Number:
10495579
A system includes a beam steering assembly configured to adjust an incident beam to form a corrected beam; a beam monitoring assembly configured to generate monitoring data for the corrected beam including one or more offset parameters of the corrected beam; and a controller configured to store one or more zero parameters of the corrected beam, calculate at least one difference between the one or more zero parameters and the one or more offset parameters of the corrected beam, determine…
Methods and apparatus for measuring height on a semiconductor wafer
Granted: December 3, 2019
Patent Number:
10495446
Disclosed are apparatus and methods for determining height of a semiconductor structure. The system includes an illumination module for directing one or more source lines or points towards a specimen having multiple surfaces at different relative heights and a collection module for detecting light reflected from the surfaces. The collection module contains at least two detectors with one slit or pinhole in front of each detector that that are positioned to receive light reflected from…
Nanocrystal-based light source for sample characterization
Granted: December 3, 2019
Patent Number:
10495287
A broadband illumination source is disclosed. The broadband illumination source may include a pump source configured to generate pump illumination. The broadband illumination also includes an active medium containing nanocrystals. The broadband illumination source includes pump illumination optics configured to direct pump illumination into the active medium. The active medium is configured to emit broadband illumination by down-converting a portion of the pump illumination via…
Metrology systems and methods for process control
Granted: November 26, 2019
Patent Number:
10490462
Methods and systems for estimating values of parameters of interest based on repeated measurements of a wafer during a process interval are presented herein. In one aspect, one or more optical metrology subsystems are integrated with a process tool, such as an etch tool or a deposition tool. Values of one or more parameters of interest measured while the wafer is being processed are used to control the process itself. The measurements are performed quickly and with sufficient accuracy to…
Wafer inspection
Granted: November 26, 2019
Patent Number:
10488348
Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered…
Self directed metrology and pattern classification
Granted: November 19, 2019
Patent Number:
10483081
Methods and systems for determining parameter(s) of a process to be performed on a specimen are provided. One system includes one or more computer subsystems configured for determining an area of a defect detected on a specimen. The computer subsystem(s) are also configured for correlating the area of the defect with information for a design for the specimen and determining a spatial relationship between the area of the defect and the information for the design based on results of the…
Method and system for defect classification
Granted: November 19, 2019
Patent Number:
10482590
Defect classification includes acquiring one or more images of a specimen, receiving a manual classification of one or more training defects based on one or more attributes of the one or more training defects, generating an ensemble learning classifier based on the received manual classification and the attributes of the one or more training defects, generating a confidence threshold for each defect type of the one or more training defects based on a received classification purity…
Calibration of a small angle X-ray scatterometry based metrology system
Granted: November 19, 2019
Patent Number:
10481111
Methods and systems for calibrating the location of x-ray beam incidence onto a specimen in an x-ray scatterometry metrology system are described herein. The precise location of incidence of the illumination beam on the surface of the wafer is determined based on occlusion of the illumination beam by two or more occlusion elements. The center of the illumination beam is determined based on measured values of transmitted flux and a model of the interaction of the beam with each occlusion…
Automatic determination of fourier harmonic order for computation of spectral information for diffraction structures
Granted: November 19, 2019
Patent Number:
10481088
Automatic determination of Fourier harmonic order for computation of spectral information for diffraction structures described. An embodiment of a method includes automatically determining a Fourier harmonic order for computation of spectral information for periodic structures, wherein the determination of the Fourier harmonic order is based at least in part on the pitches in each of multiple directions of the periodic structures, material properties of the periodic structures, and…
Dual mode inspector
Granted: November 12, 2019
Patent Number:
10475173
A dual mode inspector includes an optical inspector configured to detect a defect located at a first location on a sample, a microscope configured to capture an image of the defect at the first location on the sample, and a platform that is configured to support the sample. The sample is not removed from the platform between the detecting of the defect located at the first location on the sample and the capturing of the image of the defect at the first location on the sample. The dual…
