在積體電路製程技術不斷進步之下，電子元件的積集度大幅增加，而尺寸則越做越小，此時線路訊號之傳導遲滯(RC Delay)效應將越來越明顯而限制了製程技術的發展，故傳統的鋁導線製程已不符時代需求。銅導線因具有較低的電阻係數(Resistivity)及良好的抗電遷移(Electromigration)能力等優點而成為下一世代製程導線的主流，然而其容易氧化的特性卻會嚴重影響到製程的可靠度(Reliability)，故銅導線的氧化效應是目前發展銅製程所需面對的一大課題。
本實驗主要利用電性測試的方法量測銅薄膜試片，研究試片在不同溫度下持溫，其電阻值變化與溫度、時間的關係，並對其動力學機制進行深入的探討。研究發現，結構較為鬆散的銅薄膜試片在低於100°C的溫度下持溫時，其電阻值會隨著時間呈現拋物線下降的趨勢，而結構緻密的試片其電阻值隨時間則只略為下降，二者的氧化現象皆不明顯。另一方面，將試片保持在大氣環境及200°C以下的溫度，可以估算得到低溫時銅氧化的活化能值約為0.85 0.09eV。由估算的氧化物厚度與時間之關係曲線來推測，當在大氣環境下，銅薄膜的氧化將以擴散控制機制為主；而在純氧環境下，則以反應控制機制為主。故由此可知銅薄膜會因為不同測試條件的改變，而轉換其氧化物生成的控制機制，或是介於這兩種控制機制之間。
另外，經由X光繞射分析(XRD)發現，在低溫時，不管是結構較鬆散或較緻密的銅薄膜試片，其氧化物主要成份皆為Cu2O，而若從微結構的觀點來看，銅氧化掃描式電子顯微鏡(SEM)觀測中發現氧化物係以一種孤島狀的形式生長，符合文獻報告之成長模式。

With the evolution of VLSI process technology, the continuous shrinkage device feature size leads to an increase in the density of integrated circuits (ICs). The effect of RC delay in ICs will become significant and limit the advance of process technology. Traditional Al metallization can not meet the demand and will be replaced by Cu metallization, due to the advantages of low resistivity and high electromigration resistance. However, the characteristic of Cu oxidation may seriously damage the reliability of Cu interconnects. The effect of oxidation in Cu wiring is an important problem and need to be solved in the future development of Cu process technology.
In the experiment the in-situ resistivity measurement was utilized to study the oxidation kinetics of Cu thin films. The relation between the change of Cu thin film resistance as a function of annealing temperature and time was investigated. The temperature dependence of Cu oxidation kinetics was also discussed. The experimental results show that the resistance of Cu thin films with lousy microstructure which were annealed below 100°C will drop parabolically with increasing annealing time, but decreased slightly for dense Cu thin films. Both two samples did not show obvious oxidation. In addition, when Cu is annealed below 200°C in atmosphere, the activation energy of Cu oxide growth was found to be 0.85 0.09eV according to the oxide thickness calculated from the resistance curve with respect to time. It seems that diffusion control would be the primary mechanism for Cu oxidation in atmosphere, and reaction control in dry O2. Therefore, Cu oxide formation mechanism may change or have a mixed control mechanism in different environments.
Finally, the XRD analysis revealed that the Cu oxides were found to be Cu2O at low oxidation temperature for both Cu samples. Besides, the SEM observation indicated that the Cu oxide grew up with isolated island shape, which agrees with the literature reported.

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