催化劑電漿前處理對奈米碳管於連線應用之研究

Plasma Pretreatment of Catalysts for Carbon Nanotube Interconnect

蔡宗閔(Chung-Min Tsai)

指導教授 ： 游萃蓉

國立清華大學/工學院/材料科學工程學系/碩士(2006年)

https://doi.org/10.6843/NTHU.2006.00500

摘要

本實驗利用電子迴旋共振系統(Electron Cyclotron Resonance System, ECR system)所產生之高密度電漿，於碳管成長前，對碳管成長之催化劑-鎢磷化鈷(CoWP)薄膜-施以各種氣體電漿前處理，並探討對碳管生長的影響。本研究證實純氫氣(H2)電漿前處理對碳管生長之密度及長度有所增進，可應用於半導體之連線(Interconnect)部分。
在電子迴旋共振系統當中，使用氬氣、氦氣、氫氣，或其混合氣體所產生之高密度電漿，對鎢磷化鈷(CoWP)薄膜施以電漿前處理，其後以熱裂解或電子迴旋共振電漿輔助化學氣相沉積法( Chemical Vapor Deposition)，於小於400 ℃的低溫狀態下，通入乙炔(C2H2)/氫氣(H2)或甲烷(CH4)/氫氣(H2)，進行奈米碳管之合成。結果顯示，經過純氫氣電漿前處理之鎢磷化鈷薄膜基板，具有均勻且細緻的奈米島狀尖錐，配合氫氣電漿對催化劑金屬的還原效應，藉此，我們可獲得生長密度更高(DCNT~1011 tubes/cm2)且長度更長(LCNT~400 nm)的奈米碳管。除此之外，更進一步成功地將奈米碳管成長於以鎢磷化鈷為擴散阻障層的銅雙層鑲嵌(Cu/low-k Dual-Damascene)之上下金屬連接窗孔結構中(窗孔大小 = 100 nm)。

關鍵字

電漿 ； 奈米碳管 ； 催化劑 ； 奈米連線 ； 連線窗孔 ； 鎢磷化鈷

並列摘要

In this work, the use of hydrogen plasma-pretreatment to enhance carbon nanotube (CNT) growth is reported for interconnect application. The cobalt tungsten phosphorous (CoWP) catalyst on copper substrate was subjected to the argon, helium and hydrogen plasma pretreatment in electron cyclotron resonance (ECR) system before the CNT growth by chemical vapor deposition from C2H2/H¬2 or CH4/H2 with or without ECR plasma enhancement CVD at 400 ℃. Results show that hydrogen plasma-pretreatment provides reduction effect on catalyst metal oxide, uniform and finer catalyst islands of CoWP substrate, resulting in denser (DCNT~1011 tubes/cm2) and longer (LCNT~400 nm) CNTs grown on the blanket CoWP and in the dual damascene via with CoWP in the via bottom.

並列關鍵字

Plasma ； Carbon Nanotube ； Catalyst ； Interconnect ； Via ； CoWP

參考文獻

[1] International Interconnect Technology Conference, IITC 2004, sponsored by IEEE, San Francisco, June 6-9 (2004)

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[3] M. Nihei, M. Horibe, A. Kawabata, and Y. Awano, Carbon Nanotube for Future LSI Interconnects, IITC 2004, pp.251-253 (2004)

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