Silicon Nitride as Top Gate Dielectric for Epitaxial Graphene
Silicon nitride (SiN) was deposited by plasma enhanced chemical vapor deposition (PECVD) as a top gate dielectric on epitaxial graphene on 6H-SiC(0001). We compare x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and transport measurements which were performed before and after the SiN deposition. We demonstrate that closed layers of SiN are formed without the need for surface activation and that the plasma process leads only to a minor degradation of the graphene. The SiN layer induces strong n-type doping. For a limited gate voltage range, a small hysteresis of 0.2 V is observed in top-gated field effect devices.
Alexander A. Lebedev, Sergey Yu. Davydov, Pavel A. Ivanov and Mikhail E. Levinshtein
P. Wehrfritz et al., "Silicon Nitride as Top Gate Dielectric for Epitaxial Graphene", Materials Science Forum, Vols. 740-742, pp. 149-152, 2013