現今科技為了追求摩爾定律，持續不斷地將電晶體尺寸微縮，企圖增加晶片上可容納電晶體的數量，進而提升電腦的運算速度，然而摩爾定律終將會迎來尺寸微縮的物理極限，需要透過單純將電晶體微縮以外的方式來達到MORE THAN MOORE的效益。將半導體製程的後段製程銅導線上以化學氣相沈積法沉積石墨烯，除了能夠提高銅電路的耐用性，可抑制銅線氧化物的形成，還能夠提升銅導線的電流傳導效率。不須增加電晶體數量，即能達到提升IC運算速度的目的。
以化學氣相沈積法沉積高品質石墨烯通常需要高達1000oC的退火溫度或生長溫度，若要應用在半導體製程中，會因為合成石墨烯所需高溫而影響前段的製程，因此以單純化學氣相沈積法在後段銅導線上生長石墨烯遲遲無法實現，而電漿增強化學氣相沉積法(Plasma-enhanced chemical vapor deposition, PECVD)雖能夠實現低溫合成石墨烯，但因為高缺陷密度而導致電路效能不彰。
為改進上述問題，本實驗主要是使用PECVD以更高活性的自由基克服了低溫下碳在金屬催化劑上的溶解度差的問題，並以苯作為生長石墨烯的碳源、銅箔作為金屬催化劑基板，全程以不影響元件性能的溫度400oC，更低溫、更節能地在銅箔上合成出連續石墨烯薄膜。實驗進一步再經由CO2連續雷射預處理銅箔，能夠將銅箔上的小銅粒、氧化銅、雜質微粒去除，並將銅箔表面處理至更加平整，藉此降低石墨烯成核密度，提升石墨烯的品質，使電流傳遞效率更進一步優化。
本實驗做了兩項實驗分析不同低溫PECVD合成石墨烯的品質變化的比較。第一項實驗為使用相同CVD生長石墨烯的參數下，將不同基板放置位置對於石墨烯品質的比較。第二項實驗為在找到最佳生長位置後，將銅箔放置在相同位置下，以相同CVD生長參數在雷射預處理銅箔前與雷射預處理銅箔後之石墨烯的品質比較。
根據實驗結果顯示，並不是距離電漿越近能量越強就越好，但若距離電漿太遠確實會因為能量不足而無法合成出石墨烯，最佳的放置位置為距離電漿約20cm處，能合成最佳品質的石墨烯。將銅箔放置在最佳位置，經過雷射預處理銅箔後，Raman圖ID/IG下降61.3%，SEM、TEM可清楚看出銅箔變得更加平整，石墨烯也更加均勻，AFM圖Rq值經雷射後也有37.38%改善幅度，C-AFM顯示出在經由雷射後生長石墨烯，電流大大提升了22倍。以上數據證明了經由CO2連續雷射來對銅箔進行預處理後，對於生長石墨烯品質有幫助，並能夠有效提升電導率，這對未來微縮晶片的趨勢具高度應用潛力。

This study proposed a synthesis strategy of high-quality graphene films on the copper foil at a temperature of 400 °C throughout the graphene growth process without employing high-temperature annealing. By subjecting the copper foil to the continuous CO2 laser pretreatment, the surface smoothness of the copper foil was improved, and copper particles and copper oxide were removed, resulting in fewer defects on the copper foil. As a result, the nucleation density of graphene was reduced, leading to a more uniform and continuous graphene film and showing an outstanding quality of graphene with low defects and low resistivity compared with other groups. We successfully overcome the challenge of high defects in graphene synthesis at a low temperature, making graphene growth compatible with existing CMOS back-end processes and accelerating the miniaturization of advanced chips.

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