However, practical use of this technique requires careful considerations in the use of the obtained pixilated or composite source and mask solutions, along with accurate modeling of mask, resist, and optics, including scanner scalar and. Osa hotspotaware fast source and mask optimization. Incorporating these more advanced models into the cadence smo software provides powerful new capabilities to the entire user community. The nikon designforyield program will include open. Optipng is a free open source batch image optimizer software for windows. Robust source and mask optimization compensating for mask. Source mask optimization study based on latest nikon. Custom source and mask optimization for 20nm sram and. Gradientbased fast source mask optimization smo juechin yu and peichen yu department of photonics and institute of electrooptical engineering, national chiao tung university, 1001 dahsueh rd.
These optimization methods, as well as other traditional rets, fix the source during the optimization and limit the degrees of freedom that can be optimized in the mask patterns. Controllable pixelated illumination opens up new regimes in control of proximity effects. Source mask optimization smo is required to extend the use of 193 water immersion lithography to the 22nm technology node. Computational lithography has come to the forefront of photolithography in 2008 as the semiconductor industry grappled with the challenges associated with the transition to 22 nanometer. Sourcemask optimization smo in optical lithography has in recent years been the subject of increased exploration as an enabler of 2220nm and beyond technology nodes 16. Process window optimization for mask aligner lithography. The use of optimization software requires that the function f is defined in a suitable programming language and connected at compile or run time to the optimization software. It has been shown that intensive optimization of the fundamental degrees of freedom in the optical system allows for the creation of nonintuitive solutions in both the source and mask, which yields improved lithographic. To realize mature smo solutions in production, the intelligent illuminator, which is an illumination system on a nikon scanner, is useful because it can provide generation of freeform sources with high fidelity to the target. Opc design, for instance, is usually limited by the competing requirements of lithography optimization and has to strike a balance between image contrast and pattern. The pixelbased method permits a large solution space, but involves a timeconsuming optimization procedure because of the large number of pixel variables.
The user may click on a check box to have the code also improve the efficiency while improving the uniformity. Abstract as optical lithography feature size shrinks further, resolution enhancement technologies rets are pushed more aggressively and often have to be considered simultaneously. In this paper, we introduce the zernike polynomials as basis functions to represent the. It has been shown that intensive optimization of the fundamental degrees of freedom in the optical system allows for the creation of nonintuitive solutions in both the source and mask, which yields improved. Pdf simulationbased euv source and mask optimization. The software also has an optimizer that allows uniformity and mask efficiency to be improved by adjusting the parameters that affect it. In various implementations, the lagrange method of optimization is employed to optimize the radiation source, wherein an optimum intensity for each pixel of the source is determined.
Whereas an entire layout design may be a few hundred millimeters squared. Combining optimization of mask layouts and the light source source mask optimization, a procedure from projection lithography, makes it possible to reduce pattern inaccuracies due to illumination errors, processing artifacts and diffraction. Delivery optimization will clear the cache when the device is running low on disk space. Computational lithography also known as computational scaling is the set of mathematical and algorithmic approaches designed to improve the resolution attainable through photolithography. In this work, a weighted smo scheme incorporating both an awareness of the hotspots and. Effective source mask optimization requires that the full degrees of freedom and actual constraints of the illumination design are incorporated into the design algorithms. For example, source position and planetary height may be adjusted to maximize uniformity for any given plume distribution m. A method and apparatus for generating a source illuminator profile and a mask design, subsequently optimizing the source illuminator profile and mask design based upon a set of target intensity profiles. Custom source and mask optimization for 20nm sram and logic michael c. Specifies the maximum size in gb of delivery optimization cache. Applicability of global source mask optimization to 22. Constrained optimization with max and absolute values in objective function. Together with mo exposure optics, lab simulation software is the enabling technology for mask aligner sourcemask optimization.
Researchers from brion and asml presented a paper on smo at another spie event last november. In fact, performing source mask optimization on an entire integrated circuit design file would take years to complete. Although smo is being aggressively pushed in volume production the layout design implications of this technology have not been openly discussed. Source mask optimization techniques are gaining increasing attention as ret computational lithography techniques in sub32nm design nodes. In this work, we explored a pointsource approach for sourcemask optimization. Introduction the concept of lithographic process window optimization2,3 goes back to the late 80s. Demonstrating the benefits of sourcemask optimization and.
As the introduction of euv lithography is at least delayed to the 22 nm technology. Osa efficient source mask optimization with zernike. Impact of realistic source shape and flexibility on source. Optimization flows of source, mask and projection optics. They plug directly into analytica optimizer with full integration of all features, including uncertainty, dynamic simulation, and intelligent arrays.
In this paper, we show, smo software is effective for current 45. Us8151223b2 source mask optimization for microcircuit. In order to produce optimum imaging fidelity with respect to. Software simulation of critical features and shortenings, optimized with customized illumination and opc. During smo, critical layout constructs are intensively optimized in both the mask and source domain, resulting in a solution for maximum lithographic entitlement. From the hardware side, advances in source technology have enabled freeform illumination. The optimization software will deliver input values in a, the software module realizing f will deliver the computed value fx and, in some cases, additional information. Customer specific illumination shaping and mask layouts. In recent years the potential of sourcemask optimization smo as an enabling technology for 22nmandbeyond lithography has been explored. The plug and play manager can use the various masters software capabilities in conjunction with recipe, mask, and wafer data to deliver optimized scanner exposure parameters left image. Beeing a multi stop route optimization software, patherizerev may be used by multiple calls to calculate and optimize routes for multiple. Route optimization api for electric vehicles ev patherizerev a solution to electric vehicles routing problem is a cross browsers rest api supporting now a maximum of 100 stops per route or request including the start destination and the end destination.
Besides png, it does not support any other image format. Pointsource approach of sourcemask optimization in this work, we explored a pointsource approach for sourcemask optimization smo for use with complex low k1 mask patterns. Layout content analysis for source mask optimization. Mask topography effects need to be taken into consideration for a more accurate solution of source mask optimization smo in advanced optical lithography. Image optimization of this software is really good as it does not deteriorate the image quality after the optimization. Us patent for discrete source mask optimization patent.
Cats mask data preparation mdp software for semiconductor, tft, hdd, mems and photonics mask and direct write equipment data preparation, is a highly scalable, easy to use, featurerich product suite which provides data prep modules for data fracture, data verification, mrc, pec, jobdeck processing, layer operations, and data sizing. In fact, if you are already using one of these solvers with their standard algebraic, try with analytica for a more visual and flexible way to. We have developed smo software, and study the efficiency of the software. A method for optimizing an illumination source for a mask illumination comprising the steps of. According to an abstract of the paper, a study of source and mask optimization for arf scanners, nikon researchers developed several prototypes of smo software and contend that even restricted smo is effective for expanding process windows. This paper presents recent experimental evidence of the performance advantage gained by intensive optimization, and enabling technologies like pixelated illumination. For example, it often takes a few days to perform source mask optimization on layout design sections as small as a few hundred square nanometers. Feasibility studies of source and mask optimization. Using this software, you can easily optimize or compress multiple png images at a time. In 22nm optical lithography and beyond, source mask optimization smo becomes vital for the continuation of advanced arf technology node development.
Source mask optimization smo is one such route to realize these image fidelity improvements. Another source and mask optimization method and system that involves optimizing the source by adjusting pixels of the source is described in u. A source and mask design layout optimization method and system that allow for simultaneous optimization of the source and mask using a cost function without constraints and within a practicable amount of time is described in a commonly assigned international patent application no. Source mask optimization smo is a useful technique for printing the integrated circuit ic on a wafer with increasingly smaller feature size. Source mask optimization smo is widely used to make stateoftheart semiconductor devices in highvolume manufacturing. Source and mask optimization has become a promising technique to push the limits of 193 nm immersion lithography.
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