| 摘要: | 石墨烯有很多優異的特質，如高光穿透率、極佳的載子遷移率、良好機械性質等，被預期為下世代可撓式元件以及電子元件材料。其中化學氣相沉積法(Chemical Vapor Deposition, CVD)為目前合成高質量與大面積石墨烯的主要方法。以往的CVD合成石墨烯技術主要受限於高溫爐體積，造成製程成本提高以及批量生產效率低。本實驗為了提高生產效率以及降低製程成本，研究在有限空間內大規模生產石墨烯的方法。透過將銅箔以及不同材料的隔離層以繞捲方式合成單層與多層石墨烯。並且進一步探討以碳布、碳紙、發泡銅以及發泡鎳不同材料作為隔離層對此繞捲合成石墨烯品質的影響，隔離層其主要目的為避免繞捲銅箔在高溫製程中因堆疊而黏合。其中，因碳布其結構規律並含有孔隙有利於反應氣體擴散，以及在高溫製程中不會參與反應等特性最適合做為合成單層石墨烯的隔離層材料。經由調整環境氣氛、成長溫度、壓力以及成長時間所獲得的單層石墨烯最大合成面積可達900 cm2，片電阻約為0.94 (kΩ/□)，I2D/IG = 1.51 ± 0.21，ID/IG = 0.14 ± 0.04；而發泡鎳具有溶碳的能力，藉由此特性作為合成多層石墨烯的隔離層材料 ；最大合成面積為100 cm2，並藉由光穿透分析為平均厚度為四層至五層的石墨烯。最後，此方法合成石墨烯單位時間內產率最大可達0.234 m2/h，與過去使用平面堆疊銅箔於一寸高溫爐的合成方法相比可以提升約450%；若將此繞捲方法延伸至六吋或八吋，其生產效率能提高到8.69 m2/h以及15.57 m2/h。因此本實驗提出一種能提高產率以及合成高結晶性石墨烯的方法，以利於往後可撓性材料生產應用。;Graphene has many excellent unique features, such as high optical transparency, excellent carrier mobility, and high mechanical strength, etc. and expected for next-generation flexible and electronic devices. Chemical vapor deposition (CVD) is the method for the synthesis of high-quality and large-area graphene; but, the area of as-grown graphene always limits by the size of the reaction furnace, which reduces production efficiency. In this experiment, we provide a developed method that improves production capacity to synthesis large-area monolayer and multilayer graphene using rolled-up copper foil with the spacer within in 1-inch furnace. Furthermore, the different materials such as carbon cloth, carbon paper, copper foam, and nickel foam selected as the spacer and the quality of as-prepared graphene further discussed. The spacer is to avoid the stacking copper foil adhesion during the high-temperature process. Among them, the carbon cloth is the suitable spacer material for synthesis monolayer graphene because of its structure, which allows reaction gas diffusion, and most important is stable during the high-temperature process. The largest area of monolayer graphene can achieve 900 cm2; the sheet resistance is around 0.94 kΩ/□, I2D/IG = 1.51 ± 0.21, ID/IG = 0.14 ±0.04. On the other hand, the nickel foam selected as the spacer for synthesis multilayer graphene, the available area of multilayer graphene is 100 cm2; and the average thickness that examined with the light transmittance is four to five layers. Finally, the production capacity can reach 0.23m2/h with a rolled-up structure, which is about 450% higher than the stacked planar copper foil in a 1-inch furnace. The production efficiency can increase to 8.69 m2/h and 15.57 m2/h when extending to a six or eight-inch furnace. Therefore, this experiment proposes a method to improve the production capacity and synthesize highly crystalline graphene, which is available for the future production and application of flexible materials. |
