We have developed an expert system based on statistical knowledge and photolithographic knowledge. The philosophy of our system is to minimize the number and the cost of the experiments to reach a final objective or to show that the process will never achieve it. The system suggests intermediate objectives to test stability of the resist sensitivity before testing the final objective i.e., an optimized process point for the photolithography of a specific level. When a partial objective is completed the system proposes a goal involving more expensive experiments, and so on, until the final objective is reached. In this paper we demonstrate the capability of our system on the more advanced photolithographic processes. The first example is the study of delay time effect on positive deep UV resists. The second example is the optimization of a deep UV negative process for the gate level. As a conclusion, a comparison between the necessary steps required for this study and a standard approach is done.
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