Applying association rules to strengthen EWMA controller of Chemical Mechanical Polishing
| Autor: | Min-Ru Zhan, 詹旻儒 |
|---|---|
| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 At present, it is important for our country to produce wafer. Howerver, saving superiority of yield and price can maintain the leader in the world. With the decrease of the feature size, flatness on the wafer is necessary. Chemical mechanical polishing is the only technique to achieve global flat. If we can enhance the performance of Chemical mechanical polishing, we can improve the quality of the wafer. Statistical Process Control (SPC) adapts to static systems. Probability distributions will change with time, and SPC does not prescribe control actions, so it is not suitable to control. Fackback control brings up control actions, but unsuitable controller leads to instable system. Run-by-Run combine two method. Exponentially weighted moving average (EWMA) be widely applied to semiconductor manufacturing processes. Because EWMA does not have good performance in aging process, we make use of the association rule to strengthen EWMA. In our research, we use association rule to extract error model. By dependence of error model, we forecast error in the future and suggest recipes to reduce error between output and goal. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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