# Electronic and Transport Properties of Epitaxial Graphene on SiC and 3C-SiC/Si: A Review
## 4 Electronic and Transport Properties: Effect of Interactions with the Surroundings
### Epitaxial Graphene-Substrate Interaction
#### 4.1.4 Impact of Growth on (100) and (111) 3C-SiC/Si  
Synthesis of EG on Si substrates received attention primarily due to its compatibility with current micromachining technology and processes, low production cost, and ability to synthesize on large areas of substrates [21, 66]. Thermal decomposition of 3C-SiC was widely adopted to form graphene on silicon substrates using 3C-SiC(111) and 3C-SiC(100) pseudo-substrates [16, 18, 20, 66, 80]. Yet, the formation EG on 3C-SiC via thermal decomposition has a limitation of inconsistent graphene coverage [102]. [PERSON] et al. [21] have overcome the coverage issue of graphene on 3C-SiC by using a liquid-phase Ni/Cu alloy-mediated graphene synthesis approach. Similar to EG formed on SiC(0001), graphitization of (111) type 3C-SiC involves a buffer layer at the EG/3C-SiC interface [18]. Figure 11 shows the presence of the buffer layer in EG/3C-SiC(111) using X-ray photoelectron spectroscopy (XPS) measurements [21], which is also demonstrated in References [103] and [17]. The existence of the buffer layer in the EG/3C-SiC(111) substrate has also been proven by the transmission electron microscopy (TEM) measurements by [PERSON] et al. [104]. Figure 11 also indicates that the EG formed on 3C-SiC(100) does not possess a buffer layer [21]. Graphene layers formed by thermal decomposition on 3C-SiC(111) are Bernal stacked as observed from scanning tunneling microscopy (STM) with a (6\(\sqrt{3}\times\) 6\(\sqrt{3}\)) rotated 30\({}^{\circ}\) construction at the interface similar to the EG on SiC(0001) [86]. On the other hand, the epi-layers on 3C-SiC(100) are rotated \(\pm\)15\({}^{\circ}\) with respect to the substrate from LEED measurements by [PERSON] et al. [105]. Graphene formed by alloy-mediated graphitization on 3C-SiC(100) and 3C-SiC(111) are turbostratic, as observed from Raman spectroscopy [21]. The band structure and electronic properties of EG/3C-SiC(111) determined using ARPES showed linear band dispersion **K** point of the Brillouin zone with the \(\mathbf{E_{\mathrm{F}}}\) -500 meV above the \(\mathbf{E_{\mathrm{D}}}\) indicating n-type monolayer graphene with doping of 10\({}^{13}\) cm\({}^{-2}\)[19; 66]. The n-type doping is also in agreement with the DFT calculations [21]. [PERSON] et al. [16] determined the linear band dispersion for EG/3C-SiC(100) using ARPES with the \(\mathbf{E_{\mathrm{F}}}\) -250 meV above \(\mathbf{E_{\mathrm{D}}}\), which indicated n-type doping. The absence of the buffer layer in EG on 3C-SiC(100) resulted in a weak interaction with the substrate, as evident from \(\mathbf{E_{\mathrm{F}}}\) closer to \(\mathbf{E_{\mathrm{D}}}\) compared to EG on 3C-SiC(111) [16]. Transport measurements of EG/3C-SiC were first obtained using field-effect transistor (FET) -based measurements by [PERSON] et al. [80] and [PERSON] et al. using EG formed by thermal decomposition [20]. However, as mentioned in Section 3.3, these measurements are dependent on geometry and electrostatics, and are influenced by the substrate as well as the graphene that has an issue of inconsistent coverage over the substrate [61; 102]. In addition, [PERSON] et al. reported that the EG grown on 3C-SiC on Si wafers are prone to severe 3C-SiC/Si interface degradation and the lack of large scale continuity of EG over 3C-SiC [106; 107]. The prior attempts by [PERSON] et al. and [PERSON] et al. did not address these limitations. The alloy-mediated graphitization using 3C-SiC synthesized on highly-resistive Si wafers from Reference [21] overcame the interface degradation and continuous graphene coverage issues and enabled the large scale transport properties of EG using vdP Hall effect measurements, as given below. The vdP transport measurements on EG from Reference [21] indicated that the EG-substrate interaction dominates the charge transport within EG.