Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/2583
標題: 奈米級磨粒粒徑對晶圓銅膜化學機械拋光效應之實驗探討
An Experimental Study on Size Effects of Nano Powder on Chemical-Mechanical Polishing of Copper Film
作者: 高進峰
關鍵字: 化學機械研磨;cmp;粒徑
出版社: 機械工程學系
摘要: 
隨著積體電路製程的發展,銅由於具較低的電阻值和較高的電致遷移阻抗,故在製程中逐漸取代鋁金屬,同時在多層金屬化導体連線製作日趨複雜的需求下,晶圓表面必須提高平坦度以滿足曝光製程的需求,化學機械拋光是目前唯一能達到全面性平坦化的關鍵技術,然而現有的製程條件,欠缺對於奈米級拋光粉體粒徑對製程影響的探討。故本文以實驗的方式探討銅膜在不同拋光液的環境下,化學機械拋光粉體粒徑大小對於拋光效果的影響。
文中實驗規劃二次粒徑約為26nm與40nm之氧化鋁表面改質矽膠粉體100S與200S和粒徑90nm氧化鋁粉體三種不同粉體,分別在以硝酸添加檸檬酸以及添加苯基疊氮為拋光液的環境下進行平坦化拋光,實驗結果顯示(1)以硝酸添加檸檬酸為拋光液的環境下,銅膜移除率會隨著拋光粉體二次粒徑增加而提高,同時表面粗糙度隨之變差;(2)以硝酸添加苯基疊氮為拋光液的環境下,採用氧化鋁粉體相對於氧化鋁表面改質矽膠粉體移除率明顯較高,但是銅膜移除不隨著拋光粉體二次粒徑增加而變化,同時表面粗糙度隨粒徑增加有降低的趨勢;(3)銅膜移除率隨粉體粒徑增加而提升的效果,在硝酸添加檸檬酸的拋光液中較在添加苯基疊氮的拋光液中為強烈;(4)利用Hertz接觸理論之機械磨耗模式,在硝酸添加檸檬酸溶液的拋光液中仍具良好適用性。

Copper has gradually substitute aluminum in the integrated circuit (IC) fabrication process owing to its low electrical resistivity and high electron-migration resistance. Moreover, due to the increasing complexity of IC devices at multi-level metallization, the wafer must be further planarized to satisfy the requirement of the lithography process. Currently chemical mechanical polishing (CMP) is the only process to achieve globe planarization. However, there is lacking of study on the size effects of polishing powders on the process. In this thesis, experiments are designed and conducted to investigate the effects of polishing powders with various diameters in nanometer scale for CMP of copper film under different polishing slurries.
Alumina Modified Colloidal Silica 100S (26nm) and 200S (40nm), and Al2O3 abrasive (90nm), are used as polishing powders in this study. Experiments showed the following results. (1) The removal rate (RR) of the film increases with diameters of the polishing powder under an additive of Citric Acid in HNO3. Surface quality becomes worse at the same time. (2) With benzotriazole (BTA) as an additive, RR of the film using Al2O3 powder is higher, but RR does not increase with the powder size in general. Surface quality becomes worse at the same time though it is not as strong as that in the slurry with additive of Citric Acid. (3) The size effect of powders on RR with additive of Citric Acid is stronger than that with BTA. (4) The mechanical wear model based on Hertz contact theory can be employed in the CMP process when Citric Acid is used as an additive in the slurry.
URI: http://hdl.handle.net/11455/2583
Appears in Collections:機械工程學系所

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