本研究是利用調配鎢磷化鈷(CoWP)催化劑成分及結構，以及改變無電鍍的成長條件，來增加碳奈米線成長的密度，做為半導體連線(interconnect)。在此，選用Cu / Ti / SiO2基座來調配CoWP，以及TSMC提供之含有下銅導線及直徑約70 nm大小之連接窗口（via-hole）之晶片，以作為成長碳奈米線via用的基座及後續電性量測。在無電鍍鎢磷化鎢方面，本研究改變酸鹼值(pH)，電鍍的溫度、及時間，進而改變沉積鎢磷化鎢的表面形貌及成分，以達到成長高密度碳奈米線的目的，此外，亦利用，改變鎢在無電鍍溶液中的濃度(0 - 0.18 mol/L)，來調配CoWP成分，進而探討其對碳奈米線成長的影響。隨後利用本實驗室(BNE Lab)的化學氣相沉積系統，以乙炔(C2H2)為氣源，以氬氣(Ar)稀釋及以氫氣(H2)為活化催化劑，在分壓為0.05-2.5 Torr，≦400 oC下成長碳奈米線，經過不斷的實驗，來調配出成長奈米線的最佳化條件，其碳奈米線密度可達1.1x1011 / cm2
而在電性量測方面，則在上下之via上，利用聚焦離子束電子顯微鏡沈積白金(Pt)，作為量測用的電極，隨後再利用多探針奈米電性量測系統量測奈米線via的電性。目前可量到的via阻值為7.2k Ω / via。此阻值仍偏高，須進一步改進，以達半導體金屬連線之需求。

This work is focused on the optimization on the composition and structure of electroless CoWP catalyst to enhance the carbon nanowire growth for interconnect application. The blanket (Cu/Ti/SiO2/Si) wafers were used to optimize the electroless plating process of CoWP for carbon nano-wire (CNW) growth. The structure wafers (provided by TSMC) with 70 nm via and Cu line underneath were used to measure via- resistance after CNW growth. The pH value, plating temperature, and plating time were optimized to modify the morphology of CoWP for CNW growth. Besides, the effect of W concentration on CNW growth was also investigated. The CNWs were grown by the chemical vapor deposition (CVD) at 400 oC, using C2H2 as a reaction gas at 0.05 – 2.5 Torr with Ar as a carrier gas and H2 to activate the catalyst.
For CNW-via resistance measurement, Pt was deposited on the CNW-via by focus-ion-beam technique. The CNW-via resistance was measured by Multi-Probe Nano-Electronics Measurement (MPNEM) system. The ohmic behavior and a resistance of 7.2k Ω/via of CNW-vias was measured, which needs further improvement for future interconnect application.

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