Abstract: A mask layout containing a non-Manhattan pattern is received. The received mask layout is processed. An edge of the non-Manhattan pattern is identified. A plurality of two-dimensional kernels is generated based on a set of processed pre-selected mask layout samples. The two-dimensional kernels each have a respective rotational symmetry. The two-dimensional kernels are applied to the edge of the non-Manhattan pattern to obtain a correction field for the non-Manhattan pattern. A thin mask model is applied to the non-Manhattan pattern. The thin mask model contains a binary modeling of the non-Manhattan pattern. A near field of the non-Manhattan pattern is determined by applying the correction field to the non-Manhattan pattern having the thin mask model applied thereon. An optical model is applied to the near field to obtain an aerial image on a wafer. A resist model is applied to the aerial image to obtain a final resist image on the wafer.

Abstract: Examples of synchronized parallel tile computation techniques for large area lithography simulation are disclosed herein for solving tile boundary issues. An exemplary method for integrated circuit (IC) fabrication comprises receiving an IC design layout, partitioning the IC design layout into a plurality of tiles, performing a simulated imaging process on the plurality of tiles, generating a modified IC design layout by combining final synchronized image values from the plurality of tiles, and providing the modified IC design layout for fabricating a mask. Performing the simulated imaging process comprises executing a plurality of imaging steps on each of the plurality of tiles. Executing each of the plurality of imaging steps comprises synchronizing image values from the plurality of tiles via data exchange between neighboring tiles.

Abstract: A mask layout containing a non-Manhattan pattern is received. The received mask layout is processed. An edge of the non-Manhattan pattern is identified. A plurality of two-dimensional kernels is generated based on a set of processed pre-selected mask layout samples. The two-dimensional kernels each have a respective rotational symmetry. The two-dimensional kernels are applied to the edge of the non-Manhattan pattern to obtain a correction field for the non-Manhattan pattern. A thin mask model is applied to the non-Manhattan pattern. The thin mask model contains a binary modeling of the non-Manhattan pattern. A near field of the non-Manhattan pattern is determined by applying the correction field to the non-Manhattan pattern having the thin mask model applied thereon. An optical model is applied to the near field to obtain an aerial image on a wafer. A resist model is applied to the aerial image to obtain a final resist image on the wafer.

Abstract: A mask layout is received. An interaction-free mask model is applied to the mask layout. An edge interaction model is applied to the mask layout. The edge interaction model describes an influence due to a plurality of combinations of two or more edges interacting with one another. A thin mask model is applied to the mask layout. A near field is determined based on the applying of the interaction-free mask model, the applying of the edge interaction model, and the applying of the thin mask model.

Abstract: A technique for calculating a second aerial image associated with a photo-mask that can be used to determine whether or not the photo-mask (which may include defects) is acceptable for use in a photolithographic process is described. In particular, using a first aerial image produced by the photo-mask when illuminated using a source pattern and an inspection image of the photo-mask, a mask pattern corresponding to the photo-mask is determined. For example, the first aerial image may be obtained using an aerial image measurement system, and the inspection image may be a critical-dimension scanning-electron-microscope image of the photo-mask. This image, which has a higher resolution than the first aerial image, may indicate spatial-variations of a magnitude of the transmittance of the photo-mask. Then, the second aerial image may be calculated based on the determined mask pattern using a different source pattern than the source pattern.

Abstract: A technique for calculating a second aerial image associated with a photo-mask that can be used to determine whether or not the photo-mask (which may include defects) is acceptable for use in a photolithographic process is described. In particular, using a first aerial image produced by the photo-mask when illuminated using a source pattern and an inspection image of the photo-mask, a mask pattern corresponding to the photo-mask is determined. For example, the first aerial image may be obtained using an aerial image measurement system, and the inspection image may be a critical-dimension scanning-electron-microscope image of the photo-mask. This image, which has a higher resolution than the first aerial image, may indicate spatial-variations of a magnitude of the transmittance of the photo-mask. Then, the second aerial image may be calculated based on the determined mask pattern using a different source pattern than the source pattern.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: A method for determining a surface in a material is described. During this method, arrival times of a wavefront at a first depth in the material are calculated using an Eikonal equation. Note that the first depth is proximate to an outer surface of the material. Next, arrival times of the wavefront at a second depth in the material are calculated using the Eikonal equation and the calculated arrival times at the first depth. Then, the surface in the material is determined based on the calculated arrival times at the first depth, the calculated arrival times at the second depth, and a given time interval. Note that arrival times at a given depth in the material, which includes the first depth or the second depth, are calculated by directly determining a steady-state solution of the Eikonal equation.

Abstract: A method for determining a mask pattern to be used on a photo-mask in a photolithographic process is described. During the method, a target pattern that includes at least one continuous feature is provided. Then a mask pattern that includes a plurality of distinct types of regions corresponding to the distinct types of regions of the photo-mask is determined. Note that the mask pattern includes at least two separate features corresponding to at least the one continuous feature. Furthermore, at least the two separate features are separated by a spacing having a length and the spacing overlaps at least a portion of at least the one continuous feature.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: A method for determining a mask pattern to be used on a photo-mask in a photolithographic process is described. During the method, a target pattern is partitioning into subsets, which are distributed to processors. Then, a set of second mask patterns, each of which corresponds to one of the subsets, is determined. Moreover, at least one of the second set of mask patterns may be determined by: providing a first mask pattern that includes distinct types of regions corresponding to distinct types of regions of the photo-mask, calculating a gradient of a function, and determining a second mask pattern based, at least in part, on the gradient. Note that the function may depend on the first mask pattern and an estimate of a wafer pattern that results from the photolithographic process, and that the gradient may be calculated in accordance with a formula obtained by taking a derivative of the function.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by mask functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks. An accurate, slower merit function may be used to determine adjustment parameters for a faster, approximate merit function. The faster merit function may be used for iteration and adjusted based on the adjustment parameters.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.

Abstract: Photomask patterns are represented using contours defined by level-set functions. Given target pattern, contours are optimized such that defined photomask, when used in photolithographic process, prints wafer pattern faithful to target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic process, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns), robustness against process variations, as well as restrictions imposed relating to practical and economic manufacturability of photomasks.