AUTOMATIC SYNTHESIS OF EQUIPMENT RECIPES FROM SPECIFIED WAFER-STATE TRANSITIONS

Run-to-run and supervisory control algorithms determine the equipment recipe to produce a desired output wafer state given the incoming wafe r state and the current equipment model. For simple, low-dimensional e quipment models, this problem is not difficult. However, when there ar e multiple responses for the system and the equipment models are nonli near, automated synthesis of recipes is complicated by the potential f or multiple solutions. While there are standard techniques for handlin g such inverse problems in general, each of these techniques is optima l only under certain conditions, We present a framework for performing automated synthesis of recipes that integrates database search, local optimization, and global optimization into a consistent methodology t hat is applicable to a wide range of equipment models and inversion pr oblems in general. The integrated framework imposes quasi-continuity o n the extracted recipes, is scalable to systems of high dimensionality , and can be optimized to minimize the expected synthesis time for any given problem. The framework has been implemented in a system that pe rforms statistical optimization of CMOS transistor designs. The integr ated framework provides a factor of 16 increase in performance over gl obal optimization and a factor of three increase over exhaustive searc h and multiple starts of a local optimizer.