壓力、轉速與研磨液流量對鎢金屬化學機械研磨製程中移除率及均勻度之影響

Abstract

摘要 在深次微米到奈米半導體製程中，由於微影暴光解析度的增加，伴隨著景深的縮減，且由於元件的密度增加，多層導體連線的設計使全域平坦化技術成為深次微米到奈米半導體製程中最基本之關鍵技術，化學機械研磨製程(CMP, Chemical Mechanical Polishing)是目前唯一可達全域平坦化技術，為一道非常重要之積體電路平坦化製程。 本篇論文是藉由沈積鎢金屬之晶圓，去探討在化學機械研磨製程中利用調整化學機械研磨頭模組之壓力及轉速，對鎢金屬薄膜之研磨率與均勻度之影響研究。實驗結果指出，在一定範圍下提高研磨頭模組之壓力，對研磨率及均勻度之改善均有幫助。另一方面，提高研磨頭模組之轉速，亦會對鎢金屬薄膜產生影響。於實驗過程中嚐試利用研磨頭模組之壓力及轉速，找出最佳之研磨率及均勻度。最後歸納本實驗之所有數據，得知在一定之條件下， 研磨頭模組之壓力在5 psi，研磨頭模組之轉速為360rpm時，得到之結果最佳。其研磨率大概落在5000A，而均勻度則落在8% - 8.2%範圍之內。

Abstract In the deep-submicro semiconductor manufacturing, such as less then 0.5 mm devices design rule and more than three layer of interconnects, more severe the depth of focus budget of optical lithography techniques, all of these requirement need a globe planarization technique. Chemical mechanical polishing, CMP, is the only way known to achieve the globe planarization. In this experiment, the effects of Down Force and Rotation Speed on improvement of Removal Rate and Non-Uniformity are examined. The results presented distinctly suggest that the wafer Removal Rate and Non-Uniformity can be improved by increasing the wafer Down Force at certain range. Besides, the wafer Rotation Speed is also influences the process result. An attempt is made here to search for the optimal condition for the wafer Removal Rate and Non-Uniformity subjected to the constraints of the present experiment system. In this search wafer Down Force is tested at 5 psi and wafer Rotation Speed tested at 360 rpm, the wafer Removal Rate can be conclude 5000A and wafer Non-Uniformity can be descend to about 8% - 8.2%.