以電化學原子層沉積Cu薄膜在圖案化基板上的研究

Studies of Cu Thin Film by Electrochemical Atomic Layer Deposition on Pattern Substrates

蘇冠儒(Guan-Ru Su)

指導教授 ： 方昭訓

國立虎尾科技大學/工程學院/材料科學與綠色能源工程研究所/碩士(2015年)

https://doi.org/10.6827/NFU.2015.00083

摘要

近年來電化學原子層沉積技術可以製備出原子層級的薄膜，在填充溝渠具有很大潛力並且可以解決填洞與步階覆蓋性的問題，因此應用在半導體銅製程的合金薄膜具有發展潛力。
本實驗利用電化學原子層沉積Cu薄膜，在直流濺鍍 Ru薄膜的圖案化基板上，藉由欠電位沉積製作一層Cu原子，再利用欠電位沉積誘導Pb原子層，再用Cu原子表面侷限的氧化還原置換反應將Pb原子置換而形成Cu原子層，該置換循環重複50次可形成單層Cu原子層。實驗分析由能譜儀(EDS)分析薄膜成分、IV量測系統量測電性、X光繞射分析儀(XRD)進行結構分析、場發射掃描式電子顯微鏡(FE-SEM)觀察表面形貌。
實驗結果顯示利用電化學原子層沉積可在圖案化基板上製備出Cu薄膜，並且UPD-Pb電位隨越往負的電位時，Cu薄膜品質更好且在線寬200 μm、20 μm和15 μm，最低的阻值分別為3.75 Ω/□, 3.65 Ω/□ 和5.12Ω/□ 。

關鍵字

電化學原子層沉積(EC-ALD) ； 欠電位沉積 ； SLRR

並列摘要

Preparation of the atomic layer films by an electrochemical atomic layer deposition is capable of gap filling. It can be potentially adopted for interconnect manufacturing for integrated circuit.
The copper layer was deposited on a sputter-prepared Ru/Si pattern substrate by an electrochemical atomic layer deposition. A first Cu layer was deposited by an underpotential deposition, followed by a underpotential deposition of Pb. Pb was used as a sacrificial layer on the Cu/Ru/Si pattern substrate, and followed by an open circuit potential for 60s to enable a redox replacement of UPD-Pb layer by Cu2+ in a copper solution. Cu film was formed by repeated for the 50 cycles. The film composition was determined by a energy dispersive spectrometry (EDS), the resistance was measured by a current-voltage curve, crystal structure was analyzed by x-ray diffraction (XRD), and the surface morphology was observed by field emission scanning electron microscope (FE-SEM).
Cu film can be prepared in pattern substrate by ECALD. The results showed that Cu film has a smooth and dense structure when using UPD-Pb at a more negative potential. The lowest resistivity of 3.75 Ω/□, 3.65 Ω/□ and 5.12 Ω/□ for a line width of 200 μm, 20 μm, and 15 μm, respectively.

並列關鍵字

Electrochemical atomic layer deposition ； underpotential deposition (UPD) ； Surface limited redox replacement(SLRR)

參考文獻

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