隨著製程技術不斷地進步，積體電路的架構越來越複雜。一個顯而易見的事實是電路板的複雜度也隨之升高。因此，一個良好的自動化電路板繞線器對於現今的電路板設計需求而言是非常重要的。然而，現今商用的電路板繞線軟體有些問題存在。首先，在當要處理之電路板複雜度太高的情況下，商用軟體不能夠產生一個不違反設計規則的繞線結果。第二，商用軟體似乎較傾向於使用直角線路進行繞線。事實上，在某些技術上，直角繞線會造成製程問題。顯然地，要設計出一套全新的電路板繞線器並且能同時考慮各式各樣的設計規則是非常困難的。因此，我們將電路板繞線問題分成兩個階段:首先，我們使用人工繞線的方式去處理關鍵訊號線，之後再使用自動化的方式去處理不包含線長規則的非關鍵訊號線。此種非關鍵訊號線似乎較關鍵訊號線要容易解決，事實上，在處理完關鍵訊號線之後，非關鍵訊號線所能使用的繞線資源會變得非常的少。在本篇論文中，我們的貢獻可以分為以下幾點: (1) 我們提出一個針對非關鍵訊號線且能識別出各式各樣的障礙物的格點式電路板繞線器。 (2) 一種包含在我們的繞線器中的方式以避免產生直角線路。 (3) 我們將我們的繞線器與商用軟體進行比較，實驗結果顯示我們的繞線結果在短路及直角線路的數量上是優於商用軟體的。

As the manufacturing technology evolves constantly, the structure of an integrated circuit becomes more complex. An obvious fact is that the complexity of a printed circuit board (PCB) dramatically increases. Therefore, automated PCB routers become a great demand for modern PCB layout. However, commercial PCB routing tools do not work very well actually. First, they cannot generate a design rule check (DRC) clean result if the PCB is too complex. Second, they seem to prefer using right angle routes. In fact, the right angle corners would cause manufacturability problems in some technologies. Obviously, it is really hard to design a new PCB router which can consider lots of design rules simultaneously. Thus, we divide the PCB routing problem into two stages: First, we use a manual method to route critical nets. Then, we use an automatic router to focus on only non-critical nets which are not imposed with any length constraints. Such nets seem easy to route than critical nets, but their routing resources would become extremely less after routing for critical nets is done. In this thesis our contributions are: (1) We propose a grid based PCB router, which could catch a wide variety of routing obstacles, for such non-critical nets. (2) A method is included in our router to remove all the right angle corners. (3) We compare our router with a commercial tool and the quality of our routing result is better than that of the commercial tool in terms of the number of shorts and the number of right angle corners.

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