Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Materials and Devices, Soochow University , 199 Renai Road, Suzhou, Jiangsu 215123, China.
ACS Nano. 2015 Jan 27;9(1):594-601. doi: 10.1021/nn505913v. Epub 2015 Jan 2.
High-quality and wafer-scale graphene on insulating gate dielectrics is a prerequisite for graphene electronic applications. For such applications, graphene is typically synthesized and then transferred to a desirable substrate for subsequent device processing. Direct production of graphene on substrates without transfer is highly desirable for simplified device processing. However, graphene synthesis directly on substrates suitable for device applications, though highly demanded, remains unattainable and challenging. Here, we report a simple, transfer-free method capable of synthesizing graphene directly on dielectric substrates at temperatures as low as 600 °C using polycyclic aromatic hydrocarbons as the carbon source. Significantly, N-doping and patterning of graphene can be readily and concurrently achieved by this growth method. Remarkably, the graphene films directly grown on glass attained a small sheet resistance of 550 Ω/sq and a high transmittance of 91.2%. Organic light-emitting diodes (OLEDs) fabricated on N-doped graphene on glass achieved a current density of 4.0 mA/cm(2) at 8 V compared to 2.6 mA/cm(2) for OLEDs similarly fabricated on indium tin oxide (ITO)-coated glass, demonstrating that the graphene thus prepared may have potential to serve as a transparent electrode to replace ITO.
在绝缘栅介质上获得高质量、晶圆级的石墨烯是石墨烯电子应用的前提。对于此类应用，石墨烯通常是先合成，然后再转移到理想的衬底上，以便进行后续的器件加工。如果能够直接在衬底上生成石墨烯而无需转移，将极大地简化器件加工过程。然而，直接在适合器件应用的衬底上合成石墨烯虽然需求很高，但却难以实现。在这里，我们报告了一种简单的无转移方法，该方法使用多环芳烃作为碳源，能够在低至 600°C 的温度下在介电衬底上直接合成石墨烯。重要的是，通过这种生长方法可以很容易地同时实现对石墨烯的氮掺杂和图案化。值得注意的是，直接在玻璃上生长的石墨烯薄膜的方阻低至 550 Ω/sq，透光率高达 91.2%。与同样在 ITO 涂覆玻璃上制备的有机发光二极管（OLED）相比，在氮掺杂石墨烯上制备的 OLED 在 8 V 时的电流密度达到了 4.0 mA/cm(2)，而在 ITO 涂覆玻璃上制备的 OLED 为 2.6 mA/cm(2)，这表明所制备的石墨烯有望成为替代 ITO 的透明电极。
