## 3 Results and Discussion  
Figure 1a shows the scanning electron microscopy (SEM) image of 25 \(\upmu\)m thick Cu foil after graphene growth. Additional SEM and AFM images of the copper foil surface are given in the supporting information (Figure S1a,b). The surface of Cu is smooth, without pits, with an average grain size of 80-150 \(\upmu\)m. The dominant orientation of the copper grains was analyzed using the XRD method (Figure 1b,c). As follows from the X-ray diffraction analysis, the copper catalyst used has a predominant (100) orientation (Figure 1b). The measured XRD 0-20 scan (Figure 1b), shows a Cu (200) peak (20 = 50.37\({}^{\circ}\)). The presence of one diffraction peak indicates a good texture with out-of-plane grain orientation along the \(<\)100\(>\) direction. The inset to Figure 1b shows the Cu (200) peak profile, with a characteristic small width at half maximum (FWHM) of \(\sim\)0.19\({}^{\circ}\). The small value of the FWHM suggests that the Cu film has a high crystalline quality. For additional study of the texture, an incomplete X-ray pole figure (PF) (100) was assembled (Figure 1c). The maximum tilt angle at this PF does not exceed 70\({}^{\circ}\), so only the central maxima are visible. To evaluate the domain sizes and microstructure of the Cu (100) foil, an EBSD analysis was performed (Figure 1d-f). Figure 1d shows a crystallographic map of the Cu film orientation using the inverse pole figure (IPF)-Z component, which correlates spatial crystallographic orientations with respect to the normal sample surface. The color uniformity in Figure 1d (corresponding to the stereographic triangle in Figure 1e) suggests that the normal direction of the sample is \(<\)100\(>\) over the entire map. Figure S1c shows the \(<\)100\(>\) angular deviation orientation map of copper grains. The dominance of one color demonstrates the mutual direction of all copper grains along the direction with a slight misorientation of several degrees (\(\sim\)2\({}^{\circ}\)) (Figure S1d). Figure 1f shows the Cu (100) EBSD PF in the sample normal direction, which is fully consistent with the results of the X-ray diffraction (Figure 1c). After transfer to an amorphous substrate, the graphene samples were analyzed using the SEM and AFM methods to obtain information on the quality of the surface morphology, the presence of contaminants, wrinkles or various defects. Figure 2a-c shows the quality of the SiO\({}_{2}\)/Si surface morphology. The root mean square roughness (RMS) calculated from AFM data is about 0.4 nm. Figure 1: (**a**) SEM image of the 25 \(\upmu\)m Cu foil: (**b,c**) X-ray diffraction 0-20 spectrum and pole figure of a Cu (100) sample after graphene growth; the inset shows the rocking curve for the Cu (100) diffraction; (**d–f**) EBSD analysis of the Cu foil after graphene growth; (**d**) the crystallographic orientation mapping in direction normal to the sample surface; (**e**) The color code for this map is given in the stereographic triangle; (**f**) The corresponding pole figure in [001]-direction (i.e., normal to the sample surface). Contrast changes in the SEM images (Figure 2d) indicate the presence of SLG and few-layer graphene (FLG) regions, which were purposefully obtained in the process of graphene synthesis on Cu (100) by the CVD method. However, the AFM is the main method for directly determining and confirming the thickness and roughness of single- and few-layer graphene [36; 37; 38]. Figure 2e,h shows typical AFM results for transferred graphene on the SiO\({}_{2}\)/Si substrate surface. As a result of the use of liquid transfer and subsequent drying of the sample, graphene can be raised several additional angstroms above the amorphous substrate [37]. According to the measurements of the AFM profiles (Figure 2f), the height of the areas of multi-layer graphene corresponds to 0.7-0.9 nm and can be identified as two-layer graphene [38].