Control of Graphene Layer Thickness Grown on Plasma Enhanced Atomic Layer Deposition of Molybdenum Carbide

Multilayer graphene (MLG) films were grown on molybdenum carbide ($MoC_{x}$) substrates. We fabricated the catalytic $MoC_{x}$ films by plasma enhanced atomic layer deposition (PEALD) and grown the MLG by low pressure chemical vapour depostion (CVD). We show the merits of ALD catalytic substrate for CVD graphene growth with high quality MLG on large area, excellent uniformity and layer homogeneity. Moreover, we demonstrate how to achieve control of graphene layers thickness and properties, by varying the specific catalytic film chemical and physical properties. The control of growth is not digital, but is broad ranged from few layer graphene to a graphitic film of $\sim{75}$ graphene layers grown on the respective ALD catalytic substrates. Characterisation of the MLG has been performed using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), spectral ellipsometry (SE), and scanning low-energy electron microscopy (SLEEM). By varying MLG thickness in a uniform homogeneous way, we can tailor the desired MLG properties for different application needs. Furthermore, the PEALD process can be readily adapted to high volume manufacturing processes, and combined with existing production lines.