本文主要探討IGZO產品疊構中TiN在非等向性乾蝕刻機台的反應下，觀察TiN SEM Profile角度的變化。如果Profile角度過陡的情況下，在搭接下一層膜質時會有層膜龜裂的問題，導致電性異常發生。
第一步驟使用一般產品的製程參數做實驗，我們可以很明顯的發現TiN角度有過陡的情形發生，從SEM照片來看有些幾乎接近70度情況，我們希望改善角度保持在50度左右，進而提升產品良率。
第二步驟我們利用田口實驗方法L18 (2^1×3^7 )表，找出控制因子中影響Profile角度最為重要因子，再依照這些因子而設計不同的數值來進行實驗。
最後我們依田口實驗法找到最佳優化TiN角度製程參數，經實驗分析得到品質特性之顯著因子和減少變異之因子，依這些因子組合出最佳設計，使變異因素的干擾降低至最小，來達到我們想要的目的。

IGZO-TFT is included in Taiwan's panel industry by the founder of the Foxconn Technology Group - Terry Gou who had subscribed for 66% of Sharp's shares in 2016. The main technology is IGZO (Indium Gallium Zinc Oxide), which can reduce the size of transistors compared to amorphous silicon (a-Si), increase the aperture ratio of liquid crystal panel pixels, and increase the resolution.
In this study, we are looking at the change of TiN profile angle in the IGZO product stack under the response of non-isotropic dry etching machine. If the profile angle is too steep, there will be a problem of film cracking while lapping the next layer of film, resulting in electric abnormalities. The first step is to use the general product process parameters for the experiment. We can obviously find that the TiN angle is too steep, and some of them are almost 70 degrees from the SEM photos. We would like to improve the angle to keep it around 50 degrees to further improve the yielding product. In the second step, we used Taguchi's experimental method L18 table to find out the most important factors among the control factors that affect the profile angle, and then designed different values according to these factors to conduct the experiment. Finally, we found the optimized TiN angle process parameters by Taguchi's experimental method to get the significant factors of quality characteristics and to reduce variation factors by the experimental analysis. Using these combined factors creates an optimal design that minimizes the interference of variables to achieve our desired goal, and to minimize the interference of variation factors to achieve the purpose we want.

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