Abstract: Systems and methods for automatic test pattern generation (ATPG) for parametric faults are described. A model may be constructed to predict a measurement margin for an integrated circuit (IC) design based on a random sample of random variables. A set of failure events may be determined for the IC design using the model, where each failure event may correspond to a set of values of the random variables that is expected to cause a metric for the IC design to violate a threshold.

Abstract: Systems and methods for automatic test pattern generation (ATPG) for parametric faults are described. A model may be constructed to predict a measurement margin for an integrated circuit (IC) design based on a random sample of random variables. A set of failure events may be determined for the IC design using the model, where each failure event may correspond to a set of values of the random variables that is expected to cause a metric for the IC design to violate a threshold.

Abstract: A system for measuring an overlay error of a sample is disclosed. The system may include a broadband illumination source configured to emit broadband illumination. The system may also include one or more optical elements configured to direct the broadband illumination to a target disposed on the sample, wherein the one or more optical elements are configured to collect illumination from the target and direct it to a spectrometer, wherein the spectrometer is configured to disperse multiple wavelengths of the illumination collected from the sample to multiple elements of a sensor to generate a plurality of signals. The system may also include a controller configured to calculate an overlay error between a first structure and a second structure of the target by comparing the plurality of signals with a plurality of calculated signals.

Abstract: A system for measuring an overlay error of a sample is disclosed. The system may include a broadband illumination source configured to emit broadband illumination. The system may also include one or more optical elements configured to direct the broadband illumination to a target disposed on the sample, wherein the one or more optical elements are configured to collect illumination from the target and direct it to a spectrometer, wherein the spectrometer is configured to disperse multiple wavelengths of the illumination collected from the sample to multiple elements of a sensor to generate a plurality of signals. The system may also include a controller configured to calculate an overlay error between a first structure and a second structure of the target by comparing the plurality of signals with a plurality of calculated signals.

Abstract: Provided are scatterometry techniques for evaluating a 3D diffracting structure. In one embodiment, a method involves providing a 3D spatial model of the diffracting structure and discretizing the model into a 3D spatial mesh. The method includes approximating 3D fields for each element of the 3D mesh using 3D spatial basis functions and generating a matrix including coefficients of the 3D spatial basis functions approximating the fields. The coefficients of the 3D spatial basis functions are computed and used in computing spectral information for the model. The computed spectral information for the model is compared with measured spectral information for the diffracting structure. If the model is a good model fit, the method involves determining a physical characteristic of the diffracting structure based on the model of the diffracting structure.

Abstract: Disclosed is a method for manufacturing an artificial plant, comprising: manufacturing a three-dimensional fixation frame, and burying a part of the three-dimensional fixation frame into the ground; providing a plurality of temporary annular growing zones, in a bottom-up manner, on an outer peripheral surface of a part of the three-dimensional fixation frame which is out of ground; grafting saplings in a preset shape, to form a grafted sapling unit; planting a plurality of the grafted sapling units in each of the plurality of temporary annular growing zones, and fixing the grafted sapling units onto the three-dimensional fixation frame; forming a re-grafted sapling unit by grafting the grafted sapling units of the adjacent temporary annular growing zones; and forming an artificial plant when the re-grafted sapling units mature after a preset period of time.

Abstract: Provided are optimized scatterometry techniques for evaluating a diffracting structure. In one embodiment, a method includes computing a finite-difference derivative of a field matrix with respect to first parameters (including a geometric parameter of the diffracting structure), computing an analytic derivative of the Jones matrix with respect to the field matrix, computing a derivative of the Jones matrix with respect to the first parameters, and computing a finite-difference derivative of the Jones matrix with respect to second parameters (including a non-geometric parameter). In one embodiment, a method includes generating a transfer matrix having Taylor Series approximations for elements, and decomposing the field matrix into two or more smaller matrices based on symmetry between the incident light and the diffracting structure.

Abstract: Provided are techniques for numerically integrating an intensity distribution function over a numerical aperture in a manner dependent on a determination of whether the numerical aperture spans a Rayleigh singularity. Where a singularity exists, Gaussian quadrature (cubature) is performed using a set of weights and points (nodes) that account for the effect of the Wood anomaly present within the aperture space. The numerical aperture may be divided into subregions separated by curves where the Wood anomaly condition is satisfied. Each subregion is then numerically integrated and a weighted sum of the subregion contributions is the estimate of the integral. Alternatively, generalized Gaussian quadrature (cubature) is performed where an analytical polynomial function which accounts for the effect of the Wood anomaly present within the aperture space is integrated. Points and nodes generated from a fit of the analytical polynomial function are then used for integration of the intensity distribution function.

Abstract: Provided are techniques for numerically integrating an intensity distribution function over a numerical aperture in a manner dependent on a determination of whether the numerical aperture spans a Rayleigh singularity. Where a singularity exists, Gaussian quadrature (cubature) is performed using a set of weights and points (nodes) that account for the effect of the Wood anomaly present within the aperture space. The numerical aperture may be divided into subregions separated by curves where the Wood anomaly condition is satisfied. Each subregion is then numerically integrated and a weighted sum of the subregion contributions is the estimate of the integral. Alternatively, generalized Gaussian quadrature (cubature) is performed where an analytical polynomial function which accounts for the effect of the Wood anomaly present within the aperture space is integrated. Points and nodes generated from a fit of the analytical polynomial function are then used for integration of the intensity distribution function.

Abstract: Provided are techniques for numerically integrating an intensity distribution function over a numerical aperture in a manner dependent on a determination of whether the numerical aperture spans a Rayleigh singularity. Where a singularity exists, Gaussian quadrature (cubature) is performed using a set of weights and points (nodes) that account for the effect of the Wood anomaly present within the aperture space. The numerical aperture may be divided into subregions separated by curves where the Wood anomaly condition is satisfied. Each subregion is then numerically integrated and a weighted sum of the subregion contributions is the estimate of the integral. Alternatively, generalized Gaussian quadrature (cubature) is performed where an analytical polynomial function which accounts for the effect of the Wood anomaly present within the aperture space is integrated. Points and nodes generated from a fit of the analytical polynomial function are then used for integration of the intensity distribution function.

Abstract: Provided are optimized scatterometry techniques for evaluating a diffracting structure. In one embodiment, a method includes computing a finite-difference derivative of a field matrix with respect to first parameters (including a geometric parameter of the diffracting structure), computing an analytic derivative of the Jones matrix with respect to the field matrix, computing a derivative of the Jones matrix with respect to the first parameters, and computing a finite-difference derivative of the Jones matrix with respect to second parameters (including a non-geometric parameter). In one embodiment, a method includes generating a transfer matrix having Taylor Series approximations for elements, and decomposing the field matrix into two or more smaller matrices based on symmetry between the incident light and the diffracting structure.