基於影像對光學鄰近修正(OPC)後之佈局間隔檢測之前置過濾方法

Abstract

近年來光學鄰近修正廣泛的應用在半導體工業，並且有許多軟體被使用在模擬光學鄰近修正後之蝕刻結果，由於光罩蝕刻後需要針對電路圖形檢測是否符合製程限制，例如電路元件寬度、間距，這些製程限制用於避免電路元件發生擠壓或者橋接的情況。本論文提出了一個有效率的演算法針對光學鄰近修正後之模擬結果做間隔檢測。首先我們設置了前置過濾器針對低解析度影像做快速的檢查。對於距離可能發生橋接的區域，再以內插的方式提高解析度，以量測更精確的距離。一些初步的實驗結果顯示這個系統流程是同時具備高效率與高準確率的。

In recent years, optical proximity correction (OPC) technology has been widely used in semiconductor industry. Some software has been applied to simulate the exposure results for OPC photomask while other software has been used to check the (simulated) etched circuit for process constraints such as minimum spacing/width. These constraints are defined to avoid electrical failures such as bridge and pinch. This thesis research proposes an efficient algorithm to check the spacing of the OPC simulation results. The algorithm first applies a pre-filter to rapidly check minimum the spacing using low-resolution image. Sub-images for areas which may cause bridges are then restored with high resolution, through interpolation, to facilitate more precise examination of the spacing. Some preliminary experimental results show that the proposed system can provide required analyses satisfactorily in terms of accuracy and speed.