Patent application number | Description | Published |
20130182262 | Method for Reducing Wafer Shape and Thickness Measurement Errors Resulted From Cavity Shape Changes - Methods and systems for reducing wafer shape and thickness measurement errors resulted from cavity shape changes are disclosed. Cavity calibration process is performed immediately before the wafer measurement. Calibrating the cavity characteristics every time the method is executed reduces wafer shape and thickness measurement errors resulted from cavity shape changes. Additionally or alternatively, a polynomial fitting process utilizing a polynomial of at least a second order is utilized for cavity tilt estimation. High order cavity shape information generated using high order polynomials takes into consideration cavity shape changes due to temperature variations, stress or the like, effectively increases accuracy of the wafer shape and thickness information computed. | 07-18-2013 |
20130211736 | TIME-VARYING INTENSITY MAP GENERATION FOR RETICLES - An optical reticle inspection tool is used during a first inspection to obtain, for each set of one or more patch areas of the reticle, a reference average of multiple reference intensity values corresponding to light measured from sub-areas of each patch area. After using the reticle in photolithography processes, the optical reticle inspection tool is used during a second inspection to obtain, for each set of one or more patch areas, an average of multiple test intensity values corresponding to light measured from the of sub-areas. The first and second inspections use the same tool setup recipe. A difference intensity map is generated, and such map comprises map values that each corresponds to a difference between each average of the test and reference intensity values for each set of one or more patches. The difference intensity map indicates whether the reticle has degraded over time more than a predefined level. | 08-15-2013 |
20130215420 | Method and System for Determining One or More Optical Characteristics of Structure of a Semiconductor Wafer - Determination of one or more optical characteristics of a structure of a semiconductor wafer includes measuring one or more optical signals from one or more structures of a sample, determining a background optical field associated with a reference structure having a selected set of nominal characteristics based on the one or more structures, determining a correction optical field suitable for at least partially correcting the background field, wherein a difference between the measured one or more optical signals and a signal associated with a sum of the correction optical field and the background optical field is below a selected tolerance level, and extracting one or more characteristics associated with the one or more structures utilizing the correction optical field. | 08-22-2013 |
20130222795 | Optical Metrology Using Targets With Field Enhancement Elements - Methods and systems for enhancing metrology sensitivity to particular parameters of interest are presented. Field enhancement elements (FEEs) are constructed as part of a specimen to enhance the measurement sensitivity of structures of interest present on the specimen. The design of the FEEs takes into account measurement goals and manufacturing design rules to make target fabrication compatible with the overall device fabrication process. Measurement of opaque materials, high-aspect ratio structures, structures with low-sensitivity, or mutually correlated parameters is enhanced by the addition of FEEs. Exemplary measurements include critical dimension, film thickness, film composition, and optical scatterometry overlay. In some examples, a target element includes different FEEs to improve the measurement of different structures of interest. In other examples, different target elements include different FEEs. In some other examples, field enhancement elements are shaped to concentrate an electric field in a thin film deposited over the FEE. | 08-29-2013 |
20140016125 | System and Method for Apodization in a Semiconductor Device Inspection System - An inspection system with selectable apodization includes an illumination source configured to illuminate a surface of a sample, a detector configured to detect at least a portion of light emanating from the surface of the sample, the illumination source and the detector being optically coupled via an optical pathway of an optical system, a selectably configurable apodization device disposed along the optical pathway, wherein the apodization device includes one or more apodization elements operatively coupled to one or more actuation stages configured to selectably actuate the one or more apodization elements along one or more directions, and a control system communicatively coupled to the one or more actuation and configured to selectably control apodization of illumination transmitted along the optical pathway by controlling an actuation state of the one or more apodization elements. | 01-16-2014 |
20140037187 | Inspecting a Wafer and/or Predicting One or More Characteristics of a Device Being Formed on a Wafer - Methods for inspecting a wafer and/or predicting one or more characteristics of a device being formed on a wafer are provided. One method includes acquiring images for multiple die printed on a wafer, each of which is printed by performing a double patterning lithography process on the wafer and which include two or more die printed at nominal values of overlay for the double patterning lithography process and one or more die printed at modulated values of the overlay; comparing the images acquired for the multiple die printed at the nominal values to the images acquired for the multiple die printed at the modulated values; and detecting defects in the multiple die printed at the modulated values based on results of the comparing step. | 02-06-2014 |
20140071437 | Monitoring Incident Beam Position in a Wafer Inspection System - Methods, systems, and structures for monitoring incident beam position in a wafer inspection system are provided. One structure includes a feature formed in a chuck configured to support a wafer during inspection by the wafer inspection system. The chuck rotates the wafer in a theta direction and simultaneously translates the wafer in a radial direction during the inspection. An axis through the center of the feature is aligned with a radius of the chuck such that a position of the axis relative to an incident beam of the wafer inspection system indicates changes in the incident beam position in the theta direction. | 03-13-2014 |
20140098363 | SYSTEM AND METHOD FOR DETERMINING SIZE AND LOCATION OF MINIMUM BEAM SPOT - The disclosure is directed to a system and method for determining at least one characteristic of an illumination beam emanating from an illumination source. A substrate having a plurality of apertures may be actuated through an illumination beam so that apertures at different spatial offsets are scanned through the illumination beam at one or more levels of focus. Portions of illumination directed through scanned apertures may be received by at least one detector. At least one characteristic of the illumination beam may be extracted from data points associated with intensity levels associated with detected portions of illumination. Furthermore, multiple determinations of a beam characteristic made over a period of time may be utilized to calibrate the illumination source. | 04-10-2014 |
20140105482 | Detecting Defects on a Wafer Using Defect-Specific Information - Methods and systems for detecting defects on a wafer using defect-specific information are provided. One method includes acquiring information for a target on a wafer. The target includes a pattern of interest formed on the wafer and a known DOI occurring proximate to or in the pattern of interest. The information includes an image of the target on the wafer. The method also includes searching for target candidates on the wafer or another wafer. The target candidates include the pattern of interest. The target and target candidate locations are provided to defect detection. In addition, the method includes detecting the known DOI in the target candidates by identifying potential DOI locations in images of the target candidates and applying one or more detection parameters to images of the potential DOI locations. | 04-17-2014 |
20140107998 | System and Method to Emulate Finite Element Model Based Prediction of In-Plane Distortions Due to Semiconductor Wafer Chucking - Systems and methods for prediction of in-plane distortions (IPD) due to wafer shape in semiconductor wafer chucking process is disclosed. A process to emulate the non-linear finite element (FE) contact mechanics model based IPD prediction is utilized in accordance with one embodiment of the present disclosure. The emulated FE model based prediction process is substantially more efficient and provides accuracy comparable to the FE model based IPD prediction that utilizes full-scale 3-D wafer and chuck geometry information and requires computation intensive simulations. Furthermore, an enhanced HOS IPD/OPD prediction process based on a series of Zernike basis wafer shape images is also disclosed. | 04-17-2014 |
20140114597 | Systems, Methods and Metrics for Wafer High Order Shape Characterization and Wafer Classification Using Wafer Dimensional Geometry Tool - Systems and methods for improving results of wafer higher order shape (HOS) characterization and wafer classification are disclosed. The systems and methods in accordance with the present disclosure are based on localized shapes. A wafer map is partitioned into a plurality of measurement sites to improve the completeness of wafer shape representation. Various site based HOS metric values may be calculated for wafer characterization and/or classification purposes, and may also be utilized as control input for a downstream application. In addition, polar grid partitioning schemes are provided. Such polar grid partitioning schemes may be utilized to partition a wafer surface into measurement sites having uniform site areas while providing good wafer edge region coverage. | 04-24-2014 |
20140118729 | Illumination Energy Management in Surface Inspection - The disclosure is directed to a system and method of managing illumination energy applied to illuminated portions of a scanned wafer to mitigate illumination-induced damage without unnecessarily compromising SNR of an inspection system. The wafer may be rotated at a selected spin frequency for scanning wafer defects utilizing the inspection system. Illumination energy may be varied over at least one scanned region of the wafer as a function of radial distance of an illuminated portion from the center of the wafer and the selected spin frequency of the wafer. Illumination energy may be further applied constantly over one or more scanned regions of the wafer beyond a selected distance from the center of the wafer. | 05-01-2014 |
20140125978 | Film Thickness, Refractive Index, and Extinction Coefficient Determination for Film Curve Creation and Defect Sizing in Real Time - The present disclosure is directed to a method for inspecting a wafer, the wafer including a film deposited on a surface of the wafer. The film may have a thickness that varies over the surface of the wafer. The method includes the step of measuring the thickness, refractive index, and extinction coefficient of the film across the surface of the wafer. With this data a film curve is created in real time. The method also includes the step of determining a size of a defect on the surface based on at least the film curve. | 05-08-2014 |
20140133737 | Unbiased Wafer Defect Samples - Methods and systems for generating unbiased wafer defect samples are provided. One method includes selecting the defects detected by each of multiple scans performed on a wafer that have the most diversity in one or more defect attributes such that a diverse set of defects are selected across each scan. In addition, the method may include selecting the defects such that any defect that is selected and is common to two or more of the scans is not selected twice and any defects that are selected are diverse with respect to the common, selected defect. Furthermore, no sampling, binning, or classifying of the defects may be performed prior to selection of the defects such that the sampled defects are unbiased by any sampling, binning, or classifying method. | 05-15-2014 |
20140139822 | Multi-Spectral Defect Inspection for 3D Wafers - Multi-spectral defect inspection for 3D wafers is provided. One system configured to detect defects in one or more structures formed on a wafer includes an illumination subsystem configured to direct light in discrete spectral bands to the one or more structures formed on the wafer. At least some of the discrete spectral bands are in the near infrared (NIR) wavelength range. Each of the discrete spectral bands has a bandpass that is less than 100 nm. The system also includes a detection subsystem configured to generate output responsive to light in the discrete spectral bands reflected from the one or more structures. In addition, the system includes a computer subsystem configured to detect defects in the one or more structures on the wafer using the output. | 05-22-2014 |
20140151551 | METHODS AND APPARATUS FOR MEASUREMENT OF RELATIVE CRITICAL DIMENSIONS - One embodiment relates to a method of measuring a relative critical dimension (RCD) during electron beam inspection of a target substrate. A reference image is obtained. A region of interest is defined in the reference image. A target image is obtained using an electron beam imaging apparatus. The target and reference images are aligned, and the region of interest is located in the target image. Measurement is then made of the RCD within the region of interest in the target image. Another embodiment relates to a method of measuring a RCD which involves scanning along a scan length that is perpendicular to the RCD. Point RCDs along the scan length are measured. A filter is applied to the point RCDs, and an average of the point RCDs is computed. Other embodiments, aspects and features are also disclosed. | 06-05-2014 |
20140151552 | TILT-IMAGING SCANNING ELECTRON MICROSCOPE - One embodiment relates to a tilt-imaging scanning electron microscope apparatus. The apparatus includes an electron gun, first and second deflectors, an objective electron lens, and a secondary electron detector. The first deflector deflects the electron beam away from the optical axis, and the second deflector deflects the electron beam back towards the optical axis. The objective lens focuses the electron beam onto a spot on a surface of a target substrate, wherein the electron beam lands on the surface at a tilt angle. Another embodiment relates to a method of imaging a surface of a target substrate using an electron beam with a trajectory tilted relative to a substrate surface. Other embodiments and features are also disclosed. | 06-05-2014 |
20140168758 | CARBON AS GRAZING INCIDENCE EUV MIRROR AND SPECTRAL PURITY FILTER - A mirror for reflecting extreme ultraviolet light (EUV) comprising: a substrate layer; and an upper layer above the substrate layer, that reflects EUV wavelengths and refracts longer wavelengths, said upper layer being dense and hard carbon having an Sp2 to Sp3 carbon bond ratio of 0 to about 3 and a normal incidence EUV mirror comprising an optical coating on an uppermost surface which permits transmission of EUV and protects the surface from environmental degradation, said coating being dense and hard and having an Sp2 carbon bond ratio of 0 to about 3 and a thickness of 0.1 to about 5 nanometers. The invention also includes EUV mirror systems protected by a dense carbon layer and includes a multilayer EUV reflecting system having an out of band absorbing layer. | 06-19-2014 |
20140168774 | Generating an Array of Spots on Inclined Surfaces - A system which may be used to generate a plurality of spots on a surface is provided. The spots may be aligned with the incident plane of oblique illumination. The system may include a diffractive optical element configured to split a beam into a plurality of beams by generating a plurality of diffraction orders. The system may also include a focusing lens configured to focus at least some of the plurality of beams on the surface in the plurality of spots. At least some of the plurality of beams may be focused on the surface at an oblique illumination angle. The system may also include an illumination source positioned off-axis relative to an optical axis of the diffractive optical element. Using the system, a plurality of spots may be generated on an inclined surface. | 06-19-2014 |
20140185919 | Detecting Defects on a Wafer - Methods and systems for detecting defects on a wafer are provided. One method includes identifying one or more characteristics of first raw output generated for a wafer that correspond to one or more geometrical characteristics of patterned features formed on the wafer and assigning individual output in second raw output generated for the wafer to different segments based on the identified one or more characteristics of the first raw output and based on the individual output in the second raw output and individual output in the first raw output that were generated at substantially the same locations on the wafer such that the one or more geometrical characteristics of the patterned features that correspond to each of the different segments in the second raw output are different. | 07-03-2014 |
20140193065 | Detecting Defects on a Wafer Using Template Image Matching - Various embodiments for detecting defects on a wafer are provided. Some embodiments include matching a template image, in which at least some pixels are associated with regions in the device having different characteristics, to output of an electron beam inspection system and applying defect detection parameters to pixels in the output based on the regions that the pixels in the output are located within to thereby detect defects on the wafer. | 07-10-2014 |
20140195992 | Determining a Position of Inspection System Output in Design Data Space - Systems and methods for determining a position of output of an inspection system in design data space are provided. One method includes merging more than one feature in design data for a wafer into a single feature that has a periphery that encompasses all of the features that are merged. The method also includes storing information for the single feature without the design data for the features that are merged. The information includes a position of the single feature in design data space. The method further includes aligning output of an inspection system for the wafer to the information for the single feature such that positions of the output in the design data space can be determined based on the design data space position of the single feature. | 07-10-2014 |
20140199618 | METHODS OF MEASURING OVERLAY ERRORS IN AREA-IMAGING E-BEAM LITHOGRAPHY - One embodiment relates to a method of measuring overlay errors for a programmable pattern, area-imaging electron beam lithography apparatus. Patterned cells of an overlay measurement target array may be printed in swaths such that they are superposed on patterned cells of a first (base) array. In addition, the overlay array may have controlled-exposure areas distributed within the swaths. The superposed cells of the overlay and base arrays are imaged. The overlay errors are then measured based on distortions between the two arrays in the image data. Alternatively, non-imaging methods, such as using scatterometry, may be used. Another embodiment relates to a method for correcting overlay errors for an electron beam lithography apparatus. Overlay errors for a pattern to be printed are determined based on within-swath exposure conditions. The pattern is then pre-distorted to compensate for the overlay errors. Other embodiments, aspects and features are also disclosed. | 07-17-2014 |
20140240951 | Systems for Providing Illumination in Optical Metrology - The disclosure is directed to systems for providing illumination to a measurement head for optical metrology. In some embodiments of the disclosure, illumination beams from a plurality of illumination sources are combined to deliver illumination at one or more selected wavelengths to the measurement head. In some embodiments of the disclosure, intensity and/or spatial coherence of illumination delivered to the measurement head is controlled. In some embodiments of the disclosure, illumination at one or more selected wavelengths is delivered from a broadband illumination source configured for providing illumination at a continuous range of wavelengths. | 08-28-2014 |
20140253910 | System and Method for Reviewing a Curved Sample Edge - The disclosure is directed to a system and method for reviewing a curved edge of a sample. A line scan detector is actuated along an actuation path defined by the edge of the sample to scan a plurality of locations along the sample edge. The scan data is assembled to generate at least one review image of at least a portion of the edge of the sample. In some embodiments a substantially normal angle of incidence is maintained between the sample edge and the scanning illumination. In some embodiments, brightfield and darkfield images may be collected utilizing a common objective with separately operable illumination sources directing illumination along a first and second illumination path to the sample edge for review. | 09-11-2014 |
20140260640 | Interleaved Acousto-Optical Device Scanning For Suppression Of Optical Crosstalk - A method of scanning a sample includes simultaneously forming a plurality of co-linear scans. Each scan is formed by a sweep of a spot by an acousto-optical device (AOD). The co-linear scans are separated by a predetermined spacing. A first plurality of swaths are formed by repeating the simultaneous forming of the plurality of co-linear scans in a direction perpendicular to the co-linear scans. The first plurality of swaths have an inter-swath spacing that is the same as the predetermined spacing. A second plurality of swaths can be formed adjacent to the first plurality of swaths. Forming the second plurality of swaths can be performed in an opposite direction to that of the first plurality of swaths or in a same direction. An inspection system can implement this method by including a diffractive optical element (DOE) path after a magnification changer. | 09-18-2014 |
20140264051 | SEGMENTED MIRROR APPARATUS FOR IMAGING AND METHOD OF USING THE SAME - An apparatus for inspecting a photomask, comprising an illumination source for generating a light which illuminates a target substrate, objective optics for receiving and projecting the light which is reflected from the target substrate, the objective optics includes a first mirror arranged to receive and reflect the light which is reflected from the target substrate, a second mirror which is arranged to receive and reflect the light which is reflected by the first mirror, a third mirror which is arranged to receive and reflect the light which is reflected by the second mirror, and a segmented mirror which is arranged to receive and reflect the light which is reflected by the third mirror. The segmented mirror includes at least two mirror segments. The apparatus further includes at least one sensor for detecting the light which is projected by the objective optics. | 09-18-2014 |
20140268117 | SYSTEM AND METHOD TO DETERMINE DEPTH FOR OPTICAL WAFER INSPECTION - A computer-based method for inspecting a wafer, including: storing, in a memory element for at least one computer, computer readable instructions; detecting a first light beam rotating in a first spiral about a first central axis; and executing, using a processor for the at least one computer, the computer readable instructions to generate, using the detected first light beam, an image including at least one shape, determine an orientation of the at least one shape or a size of the at least one shape, and calculate a depth of a defect in the wafer according to the orientation or the size. | 09-18-2014 |
20140268118 | Multi-Spot Defect Inspection System - The disclosure is directed to a system and method for inspecting a spinning sample by substantially simultaneously scanning multiple spots on a surface of the sample utilizing a plurality of illumination beams. Portions of illumination reflected, scattered, or radiated from respective spots on the surface of the sample are collected by at least one detector array. Information associated with at least one defect of the sample is determined by at least one computing system in communication with the detector array. According to various embodiments, at least one of scan pitch, spot size, spot separation, and spin rate is controlled to compensate pitch error due to tangential spot separation. | 09-18-2014 |
20140270469 | Method and System for Reference-Based Overlay Measurement - The present invention may include acquiring a plurality of reference measurement images from a plurality of reference overlay target sites of a wafer via a reference image sampling process, wherein the reference image sampling process includes acquiring one or more images at each of a plurality of reference overlay target sites of the at least one wafer, generating a reference image by combining the plurality of reference measurement images acquired from the plurality of reference overlay target sites of the wafer of the reference image sampling process; acquiring one or more measurement images from an overlay target site of the wafer via a measurement image sampling process and measuring a virtual overlay of the one or more measurement images by comparing the one or more measurement images acquired from the overlay target site of the wafer to the generated reference image. | 09-18-2014 |
20140270474 | Detecting Defects on a Wafer - Methods and systems for detecting defects on a wafer are provided. One method includes determining difference values for pixels in first output for a wafer generated using a first optics mode of an inspection system and determining other values for pixels in second output for the wafer generated using a second optics mode of the inspection system. The first and second optics modes are different from each other. The method also includes generating a two-dimensional scatter plot of the difference values and the other values for the pixels in the first and second output corresponding to substantially the same locations on the wafer. The method further includes detecting defects on the wafer based on the two-dimensional scatter plot. | 09-18-2014 |
20140270475 | Single Die Inspection on a Dark Field Inspection Tool - Systems and methods for detecting defects on a wafer are provided. One method includes generating output for a wafer by scanning the wafer with a dark field inspection system. The method also includes generating first image data for the wafer using the output and a first cell size and second image data for the wafer using the output and a second cell size. In addition, the method includes combining the first image data and the second image data corresponding to substantially the same locations on the wafer thereby creating additional image data for the wafer. The method further includes detecting defects on the wafer using the additional image data. | 09-18-2014 |
20140313516 | Reducing Registration Error of Front and Back Wafer Surfaces Utilizing a See-Through Calibration Wafer - A calibration wafer and a method for calibrating an interferometer system are disclosed. The calibration method includes: determining locations of the holes defined in the calibration wafer based on two opposite intensity frame; comparing the locations of the holes against the locations measured utilizing an external measurement device; adjusting a first optical magnification or a second optical magnification at least partially based on the comparison result; defining a distortion map for each of the first and second intensity frames based on the comparison of the locations of the holes; generating an extended distortion map for each of the first and second intensity frames by map fitting the distortion map; and utilizing the extended distortion map for each of the first and second intensity frames to reduce at least one of: a registration error or an optical distortion in a subsequent measurement process. | 10-23-2014 |