Abstract: Disclosed concepts include a method, program product and apparatus for generating assist features for a pattern to be formed on the surface of a substrate by generating an image field map corresponding to the pattern. Characteristics are extracted from the image field map, and assist features are generated for the pattern in accordance with the characteristics extracted in step. The assist features may be oriented relative to a dominant axis of a contour of the image field map. Also, the assist features may be polygon-shaped and sized to surround the contour or relative to the inside of the contour. Moreover, the assist features may be placed in accordance with extrema identified from the image field map. Utilizing the image field map, a conventional and complex two-dimensional rules-based approach for generating assist feature can be obviated.

Abstract: A method of forming a mask having optical proximity correction features, which includes the steps of obtaining a target pattern of features to be imaged, expanding the width of the features to be imaged, modifying the mask to include assist features which are placed adjacent the edges of the features to be imaged, where the assist features have a length corresponding to the expanded width of the features to be imaged, and returning the features to be imaged from the expanded width to a width corresponding to the target pattern.

Abstract: Disclosed is a method of optimizing a design to be formed on a substrate. The method includes approximating rounding of at least one corner of an image of the design; generating a representation of the design further to the approximate rounding of the at least one corner; generating an initial representation of a mask utilized to image the design based on the representation; and performing Optical Proximity Correction (OPC) further to the initial representation of the mask.

Abstract: Disclose is a method, program product and apparatus for optimizing numerical aperture (“NA”) and sigma of a lithographic system based on the target layout. A pitch or interval analysis is performed to identify the distribution of critical pitch over the design. Based on the pitch or interval analysis, a critical dense pitch is identified. NA, sigma-in, sigma-out parameters are optimized such that the critical feature will print with or without bias adjustment. For features other than the critical dense features, adjustments are made in accordance with OPC, and lithographic apparatus settings are further mutually optimized. Accordingly, lithographic apparatus settings may be optimized for any pattern concurrently with OPC.

Abstract: Model Based Optical Proximity Correction (MOPC) biasing techniques may be utilized for optimizing a mask pattern. However, conventional MOPC techniques do not account for influence from neighboring features on a mask. This influence may be factored in the following manner—first, generating a predicted pattern from a target pattern and selecting a plurality of evaluation points at which biasing may be determined. Next, a set of multivariable equations are generated for each evaluation point, each equation representing influence of neighboring features on a mask. The equations are solved to determine that amount of bias at each evaluation point, and the mask is optimized accordingly. This process may be repeated until the mask pattern is further optimized.

Abstract: A method for modeling a photolithography process which includes the steps of generating a calibrated model of the photolithography process capable of estimating an image to be produced by the photolithography process when utilized to image a mask pattern containing a plurality features; and determining an operational window of the calibrated model, which defines whether or not the calibrated model can accurately estimate the image to be produced by a given feature in the mask pattern.

Abstract: Disclosed concepts include a method of optimizing polarization of an illumination of a pattern to be formed in a surface of a substrate. Polarized illumination is optimized by determining an illumination intensity for at least one point on an illuminator for at least two polarization states, determining image log slope for the at least one point on the illuminator for the at least two polarization states, determining a maximum image log slope (ILS) where the ILS is near zero for the at least one point on the illuminator, and selecting an optimal polarization state corresponding to the at least two polarization states that minimizes an ILS for the at least one point on the illuminator. This may be repeated for a plurality of points on the illuminator.

Abstract: Disclosed concepts include a method of optimizing polarization of an illumination of a pattern to be formed in a surface of a substrate. Polarized illumination is optimized by determining an illumination intensity for at least one point on an illuminator for at least two polarization states, determining image log slope for the at least one point on the illuminator for the at least two polarization states, determining a maximum image log slope (ILS) where the ILS is near zero for the at least one point on the illuminator, and selecting an optimal polarization state corresponding to the at least two polarization states that minimizes an ILS for the at least one point on the illuminator. This may be repeated for a plurality of points on the illuminator.

Abstract: A method of generating a mask design having optical proximity correction features disposed therein. The methods includes the steps of obtaining a desired target pattern having features to be imaged on a substrate; determining an interference map based on the target pattern, the interference map defining areas of constructive interference and areas of destructive interference between at least one of the features to be imaged and a field area adjacent the at least one feature; and placing assist features in the mask design based on the areas of constructive interference and the areas of destructive interference.

Abstract: A method of printing a pattern having vertically oriented features and horizontally oriented features on a substrate utilizing dipole illumination, which includes the steps of: identifying background areas contained in the pattern; generating a vertical component mask comprising non-resolvable horizontally oriented features in the background areas; generating a horizontal component mask comprising non-resolvable vertically oriented features in the background areas; illuminating said vertical component mask utilizing an X-pole illumination; and illuminating said horizontal component mask utilizing a Y-pole illumination.

Abstract: A method for generating models for simulating the imaging performance of a plurality of exposure tools. The method includes the steps of: generating a calibrated model for a first exposure tool capable of estimating an image to be produced by the first exposure tool for a given photolithography process, where the calibrated model includes a first set of basis functions; generating a model of a second exposure tool capable of estimating an image to be produced by the second exposure tool for the photolithography process, where the model includes a second set of basis functions; and representing the second set of basis functions as a linear combination of the first set of basis functions so as to generate an equivalent model function corresponding to the second exposure tool, where the equivalent model function produces a simulated image corresponding to the image generated by the second exposure tool for the photolithography process.

Abstract: A method of generating masks for printing a pattern including a plurality of features having varying critical dimensions. The method includes the steps of: (1) obtaining data representing the pattern; (2) defining a plurality of distinct zones based on the critical dimensions of the plurality of features; (3) categorizing each of the features into one of the plurality of distinct zones; and (4) modifying the mask pattern for each feature categorized into a predefined distinct zone of the plurality of distinct zones.

Abstract: Disclosed concepts include a method of, and program product for, optimizing an intensity profile of a pattern to be formed in a surface of a substrate relative to a given mask using an optical system. Steps include mathematically representing resolvable feature(s) from the given mask, generating a mathematical expression, an eigenfunction, representing certain characteristics of the optical system, modifying the mathematical the eigenfunction by filtering, generating an interference map in accordance with the filtered eigenfunction and the mathematical expression of the given mask, and determining assist features for the given mask based on the interference map. As a result, undesired printing in the surface of the substrate may be minimized.

Abstract: A method of generating masks for printing a pattern including a plurality of features having varying critical dimensions. The method includes the steps of: (1) obtaining data representing the pattern; (2) defining a plurality of distinct zones based on the critical dimensions of the plurality of features; (3) categorizing each of the features into one of the plurality of distinct zones; and (4) modifying the mask pattern for each feature categorized into a predefined distinct zone of the plurality of distinct zones.

Abstract: A method of generating complementary masks for use in a multiple-exposure lithographic imaging process.

Abstract: A method for generating a photolithography mask for optically transferring a pattern formed in the mask onto a substrate utilizing an imaging system.

Abstract: A method of generating complementary masks for use in a multiple-exposure lithographic imaging process.

Abstract: A method of automatically applying optical proximity correction techniques to a reticle design containing a plurality of features. The method comprises the steps of: (1) generating a first set of rules for applying scatter bar assist features to the plurality of features for a given illumination setting; (2) generating a second set of rules for applying biasing to the plurality of features for said given illumination setting; (3) forming a look-up table containing the first set of rules and the second set of rules; and (4) analyzing each of the plurality of features with the first set of rules and the second set of rules contained in the look-up table to determine if either the first set of rules or the second set of rules is applicable to a given feature. If either the first set of rules or the second set of rules is applicable to the given feature, the given feature is modified in accordance with the applicable rule.

Abstract: A method of optimizing a process for use with a plurality of lithography systems.

Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.