隨著積體電路製程技術進步，積體電路元件密集度大幅增加，電子元件尺寸越作越小，這使得電流密度逐漸增大，和產生局部的電流壅塞現象，此皆會對元件的可靠度造成不利的影響。本實驗擬藉由氫電漿的表面處理來調整銅/鉭間的接觸電阻，並利用電腦的模擬來分析銅/鉭的接觸電阻對電流壅塞的影響，
本實驗利用黃光微影製程製備試片，來探討銅/鉭接觸電阻受表面處理、電流和溫度的影響。首先利用Kelvin測試結構量測接觸電阻，接點尺寸由20×20μm2到4×4μm2。研究發現表面處理對銅/鉭間的接觸電阻有很直接的影響，表面處理可明顯的降低接觸電阻。此外接觸電阻亦會受到電流和溫度的影響，當電流越大或溫度越高時接觸電阻會有下降的趨勢。
在模擬方面，使用模擬軟體FlexPDE來分析在Blech結構中接觸電阻對電流分佈的影響。模擬結果顯示，接觸電阻的存在的確會改變電流的分佈，當接觸電阻越大，則銅膜所能達到的最大電流密度會越小，且銅導線內的電流壅塞效應越不明顯。

With the evolution of VLSI process technology, continuous scaling of integrated circuit(IC) leads to increasing density of integrated circuits(IC) regime. High current density and current crowding phenomenon associated with the scaling may cause severe reliability problems. In the experiment, we modulate the Cu/Ta contact resistance by using hydrogen plasma for Ta surface pretreatment and explore the effect of contact resistance on current crowding behavior in Cu metallization.
The samples used to study the influence of current density and surface pretreatment on the electrical/thermal properties of Cu/Ta contacts were prepared by conventional photolithography technique. A four-terminal Kelvin test structure were employed to measure the resistance of the contacts which have the contact size ranging from 4×4μm2 to 20×20μm2. It is found that the contact resistance is strongly affected by surface pretreatment conditions. Hydrogen plasma pretreatment was able to reduce the contact resistance significantly. Furthermore, the contact resistance was also affect by applied current and temperature, which decreased with increasing temperature and applied current.
In the part of simulation, an commercial software, FlexPDE, were utilized to analyze the current distribution in Blech test structure. The simulation shows that the maximum current flowing into Cu strip decrease as the contact resistance increases. Besides, high contact resistance tends to spread out the current and reduce current crowding.

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