積體電路製程之微小孔洞電鍍銅沉積技術的研究

The Study of Copper Electroplating on Sub-micron Contacts

林明頡(Ming-Jie Lin)

指導教授 ： 鄭俊麟

中原大學/工學院/化學工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500032

摘要

本研究中，我們以界面化學理論結合極化曲線量測，來探討JGB (Janus green B)與N-N雙乙基硫尿(1,3-diethyl-2-thiourea)作為化學添加劑，應用在電鍍銅沉積所扮演的角色；並研究微小孔洞之銅金屬沉積的填洞機制。
由研究結果顯示，加入JGB於含有N-N雙乙基硫尿之電鍍液中，會造成固液界面能提升，降低極化的效應，並增加銅表面之粗糙度。反之，加入N-N雙乙基硫尿於含有JGB添加劑之電鍍液中，則會造成固液界面能降低，增加極化能力，並且會增加銅晶粒之細緻性。
當電鍍溶液含有JGB 10 ppm與N-N雙乙基硫尿25 ppm時，此電鍍銅膜具有相當強之(111)/(200) 晶格強度比值與極低的表面粗糙度值；並能成功地將銅沉積於一個0.18 μm且具有深寬比為4之微小孔洞內。

關鍵字

接觸角 ； 極化曲線 ； 化學添加劑 ； 電鍍銅 ； 表面張力

並列摘要

In this study, two chemical additives, Janus green B. (JGB) and
1,3-diethyl-2-thiourea, were employed in copper electroplating. The electroplating mechanism was illustrated using interfacial theory together with polarization measurement.
Based on our studies, addition of JGB into an electroplating solution with 1,3-diethyl-2-thiourea electrolyte would increase the surface energy of liquid-solid interface, decrease the polarization, and make copper surface much more rough. On the other hand, adding 1,3-diethyl-2-thiourea into a solution containing JGB additives would decrease the surface energy, increase the polarization, and reduce the grain size of copper.
A very high intensity ratio of copper (111)/(200) and a much more smooth surface of copper have been achieved when the electroplating solution contains 10 ppm of JGB and 25 ppm of 1,3-diethyl-2-thiourea. Finally, a void-free structure with a 0.18 μm dimension of contact is demonstrated when a mixture of JGB and 1,3-diethyl-2-thiourea are used as chemical additives in copper electroplating.

並列關鍵字

polarization ； surface tension ； contact angle ； additives ； electroplated ； copper

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