Resist and Transfer Free Patterned CVD Graphene Growth on ALD Molybdenum Carbide Nano Layers

Multilayer graphene (MLG) films were grown by chemical vapour deposition (CVD) on molybdenum carbide ($MoC_{x}$) substrates. We fabricated the catalytic $MoC_{x}$ films by plasma enhanced atomic layer deposition (PEALD). The mechanism of graphene growth is studied and analysed for amorphous and crystalline $MoC_{x}$ films. In addition, the unique advantages of catalytic substrate PEALD are demonstrated in two approaches to graphene device fabrication. First, we present a complete bottom up, resist-free patterned graphene growth (GG) on pre-patterned $MoC_{x}$ PEALD performed at 50$^{\circ}C$. Selective CVD GG eliminates the need to pattern or transfer the graphene film to retain its pristine, as grown, qualities. Furthermore, we fabricated MLG directly on PEALD $MoC_{x}$ on 100 nm suspended SiN membrane. We characterise the MLG qualities using Raman spectroscopy, and analyse the samples by optical microscopy, scanning electron microscopy and X-ray diffraction measurements. The techniques of graphene device manufacturing demonstrated here pave the path for large scale production of graphene applications.