打線接合是目前最廣泛被使用的封裝內連接技術，用於將晶片內的引角與封裝作連接。儘管手指 (bonding finger) 的擺置位置和旋轉方向，對於晶片的成本和性能皆有重大的影響，在目前的設計流程中卻還是只能依賴經驗豐富的工程師以手動的方式來處理。隨著封裝內部需要被焊線的數量急遽增加，工程師將會花費更多的時間才能完成這項工作，因此，半導體封裝業界都相當期望能開發出一個快速且有效的手指擺置器來加速這個流程。開發一個自動手指擺置演算法是一件困難的任務，由於手指的形狀是非矩形的並且可以被旋轉到任意角度作，因此也無法直接透過已知的擺置演算法來解決。更重要的是，手指的擺置位置和旋轉方向皆需要滿足設計規則，以維持封裝產品的良率。因此，本篇提出了一種全新的雙正方模型來模擬一個手指，基於該模型，本篇提出了一個包含三個階段的擺置方法來解決此問題。實驗結果顯示，基於我們所開發的雙正方模型方法，可以獲得比簡單模型 (透過單一矩形模擬手指) 的方法獲得更短的線長與更小的平均旋轉角度。

Wire bonding is the most widely used interconnection technique to connect the pins of a die to a package. Although the locations and orientations of fingers have a great impact on the cost and performance of a chip, current design flow still relies on experienced engineers to handle this problem. As the number of bonding wires grows, it will require more runtime to complete this task. Thus, the semiconductor industry looks forward to developing an efficient and effective bond placement tool to speed up this procedure. Because the shapes of fingers are non-rectangular and can be rotated to arbitrary degrees, finger placement is a difficult problem and cannot be handled by existing placement algorithms directly. More importantly, the resulting placement has to meet design rules in order to increase the yield. Hence, this thesis proposes a novel double square model to approximate a finger and then presents a three-stage approach to resolve this problem based on this model. Experimental results show that our approach with the double square model can get shorter wirelength and a small finger to net rotation degree than that a model which simply uses a rectangle to represent a finger.

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