無電鍍銅錳合金薄膜抑制高溫誘發團聚行為研究

Investigation of Electroless Cu-Mn Alloy to Suppress Thermal-induced Copper Agglomeration Behaviors

陳松德(Sung-Te Chen) ； 陳錦山(Giin-Shan Chen) ； 呂育霖(Yu-Lin Lu)

《修平學報》 27期 (2013/09) Pp. 155-163

摘要

本研究以真空電漿／化學溶液雙重表面改質，採用全程濕式之無電鍍（Electroless Plating）製程，在SiO2介電層表面生長具自我強化的銅錳（Cu-Mn）合金薄膜。在無電鍍銅鍍液添加的微量Mn（0.4 at.%）元素，以共沉積方式生長的此種銅錳合金薄膜用於探討錳異質摻雜物對抑制高溫銅薄膜球狀化之影響。經高溫快速退火處理的無電鍍Cu-Mn（0.4 at.%）合金薄膜除因溫度誘發的晶粒成長外，薄膜仍能維持其連續性與完整性，但無電鍍Cu薄膜卻會有嚴重的團聚島狀化現象。同步輻射XAS能譜分析證實，經熱處理之無電鍍Cu-Mn（0.4 at.%）合金薄膜之Mn元素會因高溫偏析及氧化，並以MnO型態存在於Cu-Mn薄膜與SiO2界面處。這使得Cu-Mn（0.4 at.%）合金薄膜具有較純Cu薄膜佳的抑制高溫誘發薄膜團聚行為。

關鍵字

真空電漿表面改質 ； 無電鍍 ； 銅錳合金薄膜 ； 高溫誘發團聚

並列摘要

In this work, a nano-seeding process step, involving dual (vacuum plasma/chemical solution) surface pre-treatment, is applied for the dense growth of ultrafine (≤3 nm) seed particles on SiO2 dielectric layer, facilitating the electroless deposition of barrier-free Cu-Mn alloy thin films. The electroless Cu-Mn thin films were incorporated very minute amounts (0.4 at.%) of manganese. The synchrotron radiation XAS analysis reveals that manganese can be segregated to form an interfacial oxide layer at the SiO2/Cu interface upon high temperature annealing in an Ar-H2 atmosphere. This study demonstrated that the capacity of the electroless Cu-Mn layer in maintaining the integrity of the copper metallization layer by retarding its agglomeration into isolated islands after high temperature annealing treatment.

並列關鍵字

Vacuum Plasma ； Electroless Plating ； Cu-Mn Alloy ； Agglomeration

參考文獻

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