本論文主要是研究石墨烯與石墨烯的接觸電阻。我們使用高溫退火碳/鎳薄膜製作兩個2 mm寬的石墨烯線條，藉由兩次轉移，將石墨烯重疊成十字的圖案，然後量測這重疊的石墨烯之線電阻與接觸電阻。
我們剛開始使用非轉移的方式進行石墨烯的堆疊，但不成功，因為此方式都會產生石墨烯的裂痕及破洞。之後，我們改用文獻上常使用的傳統轉移方式去堆疊石墨烯線條，雖然可以成功地重疊石墨烯成十字的圖案，但是我們發現2 mm寬的石墨烯線條其邊緣的石墨烯厚度都會比中間的石墨烯厚，且樣品在第二次轉移浸泡水時，線條邊緣之石墨烯都會被漂浮到水面。這肇因源自於不均勻的鎳薄膜形成不均勻的石墨烯，線條外圍之石墨烯較厚因此有較差的附著力，造成外圍的石墨烯被漂浮到水面。
我們最後利用膠帶與改善遮光罩黏貼方式來改善鎳蒸鍍之均勻度，並使用均勻的鎳薄膜製作出均勻的2 mm寬石墨烯線條。經二次轉移，最後製作出十字重疊的石墨烯結構，這些 2 mm寬的石墨烯，其平均線電阻為2.275 kΩ/mm，平均接觸電阻為1.03 kΩ/mm2。

In this thesis, we investigated graphene to graphene contact resistance. Two 2-mm-wide graphene stripes were fabricated using high temperature annealing of patterned C/Ni thin films. We transferred one graphene stripe at a time on a SiO2 coated silicon wafer substrate such that the stripes cross each other. The individual stripe’s resistance and the contact resistance were measured from the fabricated samples.
At beginning, non-transfer method to stack the graphene stripes was attempted. Unfortunately, it caused lot defects such as cracks and pin holes (or missing graphene). We then use traditional graphene transfer technique to fabricate the samples. The transfer was successful, but the thickness of graphene at the stripe’s edge is thicker than the central area. Furthermore, graphene at the stripe’s edge area floated off easily when the sample soaked in the DI-water for the second transfer. The reason for graphene floated off is that a non-uniform Ni thin film causes non-uniform graphene growth across the stripe. As a result, thicker graphene was grown at the stripe’s edge which had a weaker adhesion and caused the float off.
Finally, the non-uniform Ni film was improved by a better Ni deposition method with a scotch-tape or a patterned shadow mask and the synthesized graphene stripes were uniform. The average line resistance of the 2-mm wide graphene stripe is 2.275 kΩ/mm and the average contact resistance is 1.03 kΩ/mm2.

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