高導電率的奈米銅導線具有高效率的訊號傳遞能力，可以應用在高性能半導體晶片上。半導體工業依循莫爾定律的演進，不斷地縮小各元件的特徵尺寸。對銅導線而言，微縮特徵尺寸會增加比表面積，電子傳輸過程與擴散阻障層的異質界面之非彈性散射現象變得明顯，導致銅導線的導電性質下降。另外，傳統的擴散阻障層材料也面臨電阻過大、厚度難以減小等困境。
本研究以石墨烯取代傳統的擴散阻障層，在奈米銅導線表面合成石墨烯，形成一被石墨烯包覆的銅導線結構，以拉曼光譜檢測石墨烯的品質，透過直流量測計算電阻率，利用計算相關係數("ρ" )與等效介電係數(k)分析漏電流，判斷石墨烯包覆效果與銅離子擴散程度，以及剖面銅元素成分分析觀察銅離子擴散的情形。
在真空環境下，高溫"900℃" 持溫3分鐘成長石墨烯，在"750℃" 以前控制降溫速率"-10℃/s" ，以表面析出的方式繼續成長，延長成長時間同時避免銅導線發生反濕潤現象，並利用拉曼光譜觀察到石墨烯的G、2D特徵峰值，其中"I" _"2D" ⁄"I" _"G" 在0.5~1間，表示合成出多層石墨烯，"I" _"D" ⁄"I" _"G" "在2~3" 間，帶有結構缺陷。由直流量測電壓-電流曲線，計算出包覆石墨烯後電阻率減少了21.5%，顯示石墨烯有效地減少電子在表面的非彈性散射。在銅離子擴散檢測方面，分別將樣品在"200℃、350℃、500℃" 退火兩小時，提供銅離子擴散進入氧化層所需能量與時間。不論是漏電流分析或剖面銅元素成分分析，結果皆顯示石墨烯有良好的阻擋銅離子擴散能力，但在"350-500℃" 間失效。本研究發現，石墨烯可以有效降低奈米銅導線的電阻率，並在低於"350℃" 的環境下有效阻絕銅離子擴散進入氧化層中，製備出一個具有高傳導性能與阻障銅離子擴散的奈米銅導線結構，針對半導體工業在特徵尺寸微縮上遭遇的瓶頸，提供了一個解決方案。

Copper nanowires are made by bi-layer liftoff process using e-beam lithography and e-beam evaporation. Graphene-coated copper nanowires are synthesized by the rapid thermal process with "900℃" growth temperature for 3 minute and control cooling rate until "750℃" . The raman spectrum show the G and 2D band, and the "I" _"D" "/" "I" _"G" is near 2. It represent that there is graphene with defects on the copper nanowires. The XPS spectrum show the sp2 bonded which represent the carbon-carbon bonded of graphene at binding energy 284.6 eV.
With the direct current-voltage measurent, we find that graphene reduce the resistivity of copper nanowires about 21.5%, compared to the no graphene-coated sample. It represent graphene reduce the surface scattering of electrons at the copper nanowires surface. For the purpose of analyzing the barrier property, we deposite 350nm silicon oxide layer on the sample by HDPCVD, and anneal at 200, 350, "500℃" for two hours. Using leakage current and EDS line scan measurement to analyze the barrier property. We find that the graphene will fail to diffusion barrier until 350 to "500℃" .

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