| In the last several decades, the fast developing of microelectronic technology and growing requirements from the various kind of applications make the modern integrated circuit (IC) more complicated in scale and functionality. These will inevitably lead to the higher demands for manufacturing techniques of IC systems. As far as the state of the art of IC manufacturing systems, the technique of so called Resolution Enhancement Techniques (RETs) make it possible to product features 2 or even 3 times smaller than the wavelength of illumination system. The limits of optics have been pushed well beyond what was expected just a few years ago. As for now, illumination of 193nm wavelength is used in 45nm IC production. Among all kinds of RETs, Optical Proximity Correction (OPC) is the most sophisticated and widely used technique. It achieves the aim of canceling out distortion and improving the print-ability by modifying mask patterns. Sophisticated correction algorithm, good layout design style and accurate model of lithography system are three keys of successful OPC. In this thesis we will introduce our efforts on all these three aspects.Model-based OPC (MBOPC) is an iterative process. Its convergence depends on both the initial values and the selected direction of iteration. In this thesis, a new kind of MBOPC algorithm is introduced to improve the convergent speed and convergent range, which is based on generalized intensity distribution functions and takes the interactions between edges into account. To make the new algorithm faster, a few methods to accelerate the Jacobian matrix calculation and linear system solving process is also introduced.An edge bias modeling method is developed in this thesis, which has very fast correction speed and moderate correction accuracy. Better initial values for the iterative process of conventional model-based OPC algorithm can be provided by this method, with a little run-time penalty. The number of iterations is reduced because of the better initial values. Thus the total run-time is reduced efficiently.Successful optical proximity correction also relies on layout design style. Some pattern configurations are harder to be corrected to get enough process margin, which are usually called "OPC-unfriendly" for a particular lithographic process. To save design spin time, it is necessary to find out such patterns and fix them as many as possible by the designer before layout is sent to manufacturer. This kind of OPC-aware layout design is usually called as Litho-friendly Design (LfD). In this thesis, two OPC methods based on edge bias modeling method are introduced, which are good candidates for trial-OPC in LfD.Lithography system modeling based on partial coherence imaging theory was proposed several decades ago, and widely used in the industry. However with minimum feature sizing down, more advanced configurations are used in lithography systems. When it happens, more physical phenomena in the model should be considered to keep modeling accuracy. For example vector model should be used instead of scalar model to describe systems with extremely high NA. This reality brings RET engineers a heavy task that they should build new models for new lithographic configurations, not only by changing the model parameters but also changing the model structure itself. Usually this step is not easy and time consuming. In this thesis, a new lithography modeling environment is introduced, besides implementing the conventional modeling flow, it also provides a set of handy tools to easily customize and build models for lithography system with advanced configurations. Users can build up the model by writing a concise Tcl/Tk script using tools provided by this environment, which can greatly improve the model building efficiency.
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