臺灣博碩士論文加值系統

隨著製程的不斷進步，現在晶圓的密度變得越來越高，加上運行速度也不斷地在上升，使得有越來越多項目會在同時發生轉換，因此造成晶圓上電力供應被干擾的情況變得越來越嚴重。電力供應的不穩，會引發許多嚴重的問題，其中最重要的就是會使整個晶圓的效能降低，更甚者，連功能都會發生錯誤。所以穩定的電力供應在現在的設計上是必須的。

一般來說，最常被用來解決供電干擾的方法是在晶圓上配置一些去耦合電容；去耦合電容的作用如同一個電子銀行，在平時它會儲存著電荷，當單元做轉換有需要時，它便會將其電荷釋放出來供單元做轉換使用，因此能夠有效降低供電干擾。我們發現影響供電干擾的因素，除了單元的位置之外，單元的轉換時間也是相當重要的。

在這篇論文裡，我們提出了兩個解決供電干擾的方法：首先，我們會在佈局之前，先去考慮單元的轉換時間以及單元的位置，預測哪些單元可能會發生很嚴重的供電干擾，在這些供電干擾嚴重的單元旁邊，我們先綁住一些去耦合電容，藉由這些被綁在單元旁邊的去耦合電容，我們可以在佈局之前先解決部分的供電干擾的問題；接下來，在佈局之後，我們提出另一個搬動單元的方法進一步解決供電干擾。在這個方法裡，我們會藉由改變原本單元擺放的位置，去減少原本供電干擾很嚴重的地方的干擾來源，使得整個晶圓上的電力需求變得更平均，因此也就能確實解決供電干擾的問題。

1 Introduction 1

2 Previous Work 6
2.1 Decap Allocation at Floorplan Level 6
2.2 Decap Allocation After Placement 7
2.3 Decap Allocation Before Placement 8

3 Modeling and Analysis of Power Supply Network 11

4 Design Flow 13

5 Algorithms 15
5.1 Decap Padding 15
5.2 CellMoving 20

6 Experimental Result 26

7 Conclusions 32

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