本研究中藉由化學氣相沉積法(Chemical Vapor Deposition, CVD)在銅箔表面上沉積石墨烯量子點(Graphene Quantum Dots, GQDs)，藉由不同溼式轉移(Wet transfer method)次數來改善玻璃表面上石墨烯量子點的密度與均勻度。本實驗中的參數分別為通入甲烷氣體的時間、流率以及溼式轉移的次數，最後得到最佳的光學以及電學性質的條件。本研究中無論經過多少次溼式轉移，石墨烯量子點皆為(110)的晶格取向。由拉曼光譜實驗中可以得知在不同溼式轉移次數下，驗證出本實驗中石墨烯量子點為類石墨材料(graphite-like material)。在不同溼式轉移次數下拉曼光譜中之G-band與石墨烯量子點表面密度成正比。跳躍缺陷(Hopping defect)與邊界缺陷(Edge defect)都是屬於石墨烯量子點中的缺陷。而拉曼光譜中之D-band代表著缺陷強度，此強度會隨著溼式轉移次數增加而下降。隨著溼式轉移次數增加會造成石墨烯量子點平均粒徑的上升，進而導致氧空缺(oxygen vacancies)的增加，最後造成載子濃度(Carrier concentration)上升以及載子遷移率(Carrier mobility)的下降；而不同溼式轉移次數下電阻率(Resistivity)會與石墨烯量子點表面密度反比。能階則會隨著溼式轉移次數增加而下降，能階的下降造成了在綠光以及紅光波段螢光強度的下降，而平均穿透率會隨著溼式轉移次數增加而下降。而在第2次溼式轉移條件下，石墨烯量子點擁有最低的電阻率以及第二高的穿透率；石墨烯量子點的添加使得表面電阻率相較於沒有添加石墨烯量子點的玻璃基板低。

In the present study, graphene quantum dots (GQDs) are grown on the copper foil substrate by the chemical vapor deposition (CVD) synthesis. 1~3 wet transfer numbers are then used in the preparations of the GQDs/glass substrates in order to improve the density and uniformity of GQDs via the stacking of multiple layers. The CH4 input time, flow rate, and the number of wet transfer are determined in sequence to obtain the optimum conditions in electrical (resistivity) and optical (transmittance) properties. All particles, irrespective of the number of wet transfer, are identified to be the graphene(110). The multilayered graphene is characteristically close to the graphite-like material. The G-band peak intensity in Raman analyses is varied proportional to the density of GQDs. The hopping and edge defects are identified to be existing in GQDs and the D-band related to the edge defect is lowered by increasing the number of wet transfer. Increasing the wet transfer number can lead to the rise of the mean diameter of GQDs and the amount of oxygen vacancies, thus resulting in the increase of carrier concentration and the drop of carrier mobility. The resistivity varying with the number of wet transfer is inversely proportional to the density of GQDs. Bandgap energy is slightly lowered by increasing the number of wet transfer. A bandgap reduction can bring in the lowering of photoluminescence peak intensities of green and red. The mean transmittance of specimen is slightly lowered by increasing the number of wet transfer. The specimen with 2 wet transfers has the lowest resistivity and the second highest transmittance of these specimens. GQDs can bring in a significant reduction of resistivity compared to the same substrate but without GQD.

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