**Conflict of interest**

The authors declare that there is no conflict of interest.

*Controllable Synthesis of Few-Layer Graphene on β-SiC(001) DOI: http://dx.doi.org/10.5772/intechopen.86162*

*Silicon Materials*

**5. Conclusions**

**Acknowledgements**

**Conflict of interest**

on-off current ratio of 104

.

coupling can be induced by the curvature of the ripples [116].

desirable number of graphene layers (e.g., 1, 2, or 3 ML) is synthesized.

A.A. Zakharov, B.E. Murphy, A. Locatelli, T.O. Menteş, S.L. Molodtsov,

sions and help in the preparation of this manuscript.

The authors declare that there is no conflict of interest.

and 100 μS at larger voltages when the electric current start to flow. This gives a high

This successful demonstration of the transport gap opening in the nanostructured trilayer graphene (**Figure 12**) became possible because the NBs were uniformly aligned with the step direction of the vicinal β-SiC(001) substrate (**Figure 11**), i.e., perpendicular to the current direction in the electric measurements. Note that although the NBs with asymmetrical rotation of the graphene lattices were most frequently observed, boundaries with other atomic structures were also resolved in detailed atomic resolution STM studies of several few-layer graphene/β-SiC/Si(001) samples [85, 87, 93, 101, 102]. Despite the differences in the atomic structure, STM images generally revealed extreme distortions of the overlayer near the NBs (e.g., **Figures 1(g)** and **12**). The graphene overlayer in these areas was usually bent upward and downward, forming semi-tubes with typical diameters of several nanometers. According to the STM data, the radii of curvature of the ripples in the few-layer graphene on β-SiC/Si(001) wafers were typically in the range of 2–5 nm [101]. As revealed the theoretical calculations and recent experimental studies [101], the ripples formed at the NBs could also be responsible for the opening transport gap in graphene/β-SiC/Si(001). The self-aligned nanodomain boundaries with ripples can also be utilized to add the spin degree of freedom to graphene [101], since spin-orbit

We have summarized the results of high-resolution studies of the atomic and electronic structure of few-layer graphene synthesized in UHV on β-SiC thin films epitaxially grown on the technologically relevant Si(001) wafers. LEEM, μ-LEED, ARPES, and STM studies revealed that graphene overlayer on the β-SiC/Si(001) substrates consists of nanodomains with six preferential lattice orientations and two preferential nanodomain boundary directions. The number of the boundary directions can be reduced to one using vicinal wafers with small miscuts from the Si(001) plane. Thus, self-aligned graphene nanoribbon system supported by a wide-gap semiconductor substrate could be fabricated using 2°-off Si(001) wafer. *In-situ* studies of the few-layer graphene synthesis on the β-SiC/Si(001) wafers performed in UHV using micro-spectroscopic methods demonstrate that thickness of the graphene overlayer can be controlled in the course of the high-temperature synthesis and the procedure can be stopped when a

This work was carried out within the state task of ISSP RAS and supported by the Russian Foundation for Basic Research (Grant nos. 17-02-01139, 17-02-01291) and Erasmus plus mobility grant (2016-1-IE02-KA107-000479). We thank our colleagues S.V. Babenkov, H.-C. Wu, S.N. Molotkov, D. Marchenko, A. Varykhalov,

D.V. Potorochin, J. Buck, O. Seeck, M. Hoesch, and J. Viefhaus for fruitful discus-

**148**
