Abstract: Methods, and program storage devices, for performing model-based optical lithography corrections by partitioning a cell array layout, having a plurality of polygons thereon, into a plurality of cells covering the layout. This layout is representative of a desired design data hierarchy. A density map is then generated corresponding to interactions between the polygons and plurality of cells, and then the densities within each cell are convolved. An interaction map is formed using the convolved densities, followed by truncating the interaction map to form a map of truncated cells. Substantially identical groupings of the truncated cells are then segregated respectively into differing ones of a plurality of buckets, whereby each of these buckets comprise a single set of identical groupings of truncated cells. A hierarchal arrangement is generated using these buckets, and the desired design data hierarchy enforced using the hierarchal arrangement to ultimately correct for optical lithography.

Abstract: A method for calculating long-range image contributions from mask polygons. An algorithm is introduced having application to Optical Proximity Correction in optical lithography. A finite integral for each sector of a polygon replaces an infinite integral. Integrating over two triangles, rather than integrating on the full sector, achieves a finite integral. An analytical approach is presented for a power law kernel to reduce the numerical integration of a sector to an analytical expression evaluation. The mask polygon is divided into regions to calculate interaction effects, such as intermediate-range and long-range effects, by truncating the mask instead of truncating the kernel function.

Abstract: Methods, and program storage devices, for performing model-based optical lithography corrections by partitioning a cell array layout, having a plurality of polygons thereon, into a plurality of cells covering the layout. This layout is representative of a desired design data hierarchy. A density map is then generated corresponding to interactions between the polygons and plurality of cells, and then the densities within each cell are convolved. An interaction map is formed using the convolved densities, followed by truncating the interaction map to form a map of truncated cells. Substantially identical groupings of the truncated cells are then segregated respectively into differing ones of a plurality of buckets, whereby each of these buckets comprise a single set of identical groupings of truncated cells. A hierarchal arrangement is generated using these buckets, and the desired design data hierarchy enforced using the hierarchal arrangement to ultimately correct for optical lithography.

Abstract: A method for optimizing the number of kernels N used in a sum of coherent sources (SOCS) for optical proximity correction in an optical microlithography process including setting the number of kernels N to a predetermined minimum value Nmin. A determination is made as to whether an accuracy estimate of calculated intensity is within a tolerable value. A determination is also made as to whether an added X/Y asymmetry estimate of the calculated intensity is negligible.

Abstract: A first method to compute a phase map within an optical proximity correction simulation kernel utilizes simulated wavefront information from randomly generated data. A second method uses measured data from optical tools. A phase map is created by analytically embedding a randomly generated two-dimensional array of complex numbers of wavefront information, and performing an inverse Fourier Transform on the resultant array. A filtering function requires the amplitude of each element of the array to be multiplied by a Gaussian function. A power law is then applied to the array. The elements of the array are shuffled, and converted from the phasor form to real/imaginary form. A two-dimensional Fast Fourier Transform is applied. The array is then unshuffled, and converted back to phasor form.

Abstract: Methods, and a program storage device for executing such methods, for performing model-based optical proximity correction by providing a mask matrix having a region of interest (ROI) and locating a plurality of points of interest within the mask matrix. A first polygon having a number of vertices representative of the located points of interest is computed, followed by determining a spatial relation between its vertices and the ROI. The vertices of the first polygon are then pinned to boundaries of and within the ROI such that a second polygon is formed on the ROI. The process is repeated for all vertices of the first polygon such that the second polygon is collapsed onto the ROI. This collapsed second polygon is then used to correct for optical proximity.

Abstract: Methods, and program storage devices, for performing model-based optical proximity correction by providing a region of interest (ROI) having an interaction distance and locating at least one polygon within the ROI. A cut line of sample points representative of a set of vertices, or plurality of cut lines, are generated within the ROI across at least one lateral edge of the polygon(s). An angular position, and first and second portions of the cut line residing on opposing sides of an intersection between the cut line and the lateral edge of the polygon are determined, followed by generating a new ROI by extending the original ROI beyond its interaction distance based on such angular position, and first and second portions of the cut line. In this manner, a variety of new ROIs may be generated, in a variety of different directions, to ultimately correct for optical proximity.

Abstract: A method for calculating long-range image contributions from mask polygons. An algorithm is introduced having application to Optical Proximity Correction in optical lithography. A finite integral for each sector of a polygon replaces an infinite integral. Integrating over two triangles, rather than integrating on the full sector, achieves a finite integral. An analytical approach is presented for a power law kernel to reduce the numerical integration of a sector to an analytical expression evaluation. The mask polygon is divided into regions to calculate interaction effects, such as intermediate-range and long-range effects, by truncating the mask instead of truncating the kernel function.

Abstract: Methods, and program storage devices, for performing model-based optical lithography corrections by partitioning a cell array layout, having a plurality of polygons thereon, into a plurality of cells covering the layout. This layout is representative of a desired design data hierarchy. A density map is then generated corresponding to interactions between the polygons and plurality of cells, and then the densities within each cell are convolved. An interaction map is formed using the convolved densities, followed by truncating the interaction map to form a map of truncated cells. Substantially identical groupings of the truncated cells are then segregated respectively into differing ones of a plurality of buckets, whereby each of these buckets comprise a single set of identical groupings of truncated cells. A hierarchal arrangement is generated using these buckets, and the desired design data hierarchy enforced using the hierarchal arrangement to ultimately correct for optical lithography.

Abstract: A method for calculating density maps in hierarchical designs includes the steps of deoverlapping objects in the design, providing an area of interest in the design, generating a grid in the area of interest to partition the area of interest into grid elements, determining whether the local properties of each object within the grid elements have been previously calculated, if previously calculated, adding the previously calculated value for the local properties to a corresponding grid element, otherwise, calculating the local properties of the object and summing the local properties of the objects for each associated grid element such that the local properties are calculated only once for a given object throughout the design. A system is also includes for implementing the method.

Abstract: An adaptive noise cancellation device comprises: convolution logic (10) for convolving the signal from a reference input (x) with a discretized L-tap filter to form a filtered reference signal; and logic (20) for subtracting the filtered reference signal from a signal input to form an output signal; logic for generating the filter taps as a linear combination of N basis functions each having a corresponding coefficient C.sub.k ; and logic for repeatedly determining the coefficients C.sub.k which minimize the power in the output signal (z), characterized in that N is less than the number of filter taps L and the basis functions have respective values over a portion of finite width, outside of which portion the functions are substantially zero, both in the frequency and time domains, in an embodiment they are gaussian. A full-duplex speakerphone is disclosed including such a noise cancellation device.

Abstract: A system and method for processing a stream of video image data so as to create a video representation that multiplexes data corresponding to resolution or bitstream scales. This representation is such that the identity of the basic MacroBlock (MB) structure of the MPEG-1 ISO standard is preserved across all resolution and bitstream scales, e.g. by scaling across four levels of resolution. A MacroBlock is associated with a series of attributes which contribute to the amount of overhead data incorporated in an MPEG-1 compressed data stream, so that by preserving the MacroBlock identify across multiple resolutions and bitstream scales, these scales can share this overhead, thus requiring it to be included only once in the data stream. Preserving the MacroBlock identify also simplifies significantly the derivation of motion estimation vector data for all resolution scales other than the highest resolution.

Abstract: A method of partitioning design shapes, in an E-beam lithography system, into subshapes such that a constant dose may be applied to an E-beam sensitive resist within each subshape. Within each subshape the constant dose corresponds to an approximation to an indicator function, indicative of the degree of the proximity effect, such as the effective exposure of the resist from backscattered electrons or the required dose. The error of the approximation is equal to a predetermined value for each subshape, and can depend upon the position of the subshape within the shape and the influence of errors in the applied dose at that position on the position, on development, of the edge of the shape.

Abstract: A method of proximity correction in an E-beam lithography system wherein each design shape is contracted by a predetermined bias and the E-beam dose required at any given point of the design is determined such that each of the design shapes is enlarged, on development, by the value of the predetermined bias, the determination of the E-beam dose being made in accordance with a predetermined relationship between an indicator, such as the electron backscatter, and the required E-beam dose, the indicator being defined for a plurality of points arranged on a coarse grid on the design and being indicative of the degree of the proximity effect at the respective point, the determination of the required dose being made by solving, at each of the plurality of points on the design, an integral equation relating the indicator to the E-beam dose distribution.