摘要
配合著製程技術迅速發展與改良的腳步，近年來積體電路之設計製作持續地以穩定的速度朝著微小化與高集積度的方向發展。在這同時，半導體元件主動區域內缺陷密度之控制顯然是在產品良率穩定保持上至為重要的一件工作。以深次微米元件為例，單一金屬雜質粒子的沉積即足以造成元件預設電子性質的嚴重扭曲，並導致元件失效。因此，唯有有效地控制積體電路元件內之雜質含量方可能提高產品良率；而欲達此一目的，我們必須對半導體製程中雜質進入底材的途徑與行為作更深入的探討。

受到先前有趣實驗研究結果的啟發，在本研究中我們針對半導體微影製程中金屬雜質在底材及光阻劑內的擴散行為進行理論研究；特別是要探討金屬雜質擴散率與烘烤溫度及邊界效應影響之間的關係。同時，本文中我們透過理論研究與實驗數據分析方法之擬定及應用，試圖對金屬雜質在底材及光阻劑內的擴散係數與其在二者界面上的分離係數作定量的推定；更進一步地利用分析結果重建整體擴散系統內之數據。本文所獲得的成果可用來指引將來實驗之設計規劃與數據之收集整理原則，並且用來增進實際微影製程中金屬雜質污染控制之效率。

Abstract

The increasing complexity and miniaturization of modern integrated circuits (ICs) demand a higher device yield, and hence lower defect density in the active region of silicon devices. For a deep-sub-micrometer device, a single metal precipitate could cause a distortion of electrical properties, resulting in a faulty IC. Therefore, a better knowledge of the diffusion route and behavior of metallic impurities introduced into the silicon substrate during device fabrication is essential for contamination control and for promoting the circuit yield.

Inspired by interesting previous experimental results, in this project we conduct a theoretical investigation into the problem of metallic impurity diffusion across the photoresist/substrate interface in lithographical processes for semiconductor devices. In particular, the temperature dependence of the impurity diffusion ratio, i.e., the ratio of the amount of impurities diffused into the substrate to that originally in the photoresist, is studied. Furthermore, here we quantify how much the temperature dependence of impurity diffusion ratio is altered by the effects of finite photoresist thickness. Even more aggressively, in order to fully exploit experimental results, analytical methods for extracting the values of the mass diffusion coefficients of various impurities in the substrate and photoresist, and their segregation coefficients at the interface, from experimental data are devised. It is expected that the results of this thesis will be useful for future experimental planning and for contamination control in realistic lithographical processes.

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