Figure 1

Epitaxial growth of the h-BN and graphene layers and their identification (a) STM topography of a (70 × 70) nm² h-BN covered surface obtained with V_s = 1.0 V, and I_t = 0.15 nA. (b) Scanning tunneling spectra of a clean copper substrate (gray open squares), h-BN grown on Cu(111) (full light-blue squares), graphene grown on Cu(111) (open purple circles), and graphene grown on h-BN/Cu(111) (full red circle). The purple dots represent copper surface peaks, the brown triangles denote Dirac points, and the green arrows indicate moiré potential-induced peaks (c,d) STM topography of a graphene layer grown on an (52 × 26) nm² h-BN surface epitaxially grown on a Cu(111) surface in area obtained with V_s = 4.0 V (c), 0.7 V (d) and I_t = 0.15 nA. Moiré patterns in the h-BN layer are observed at the bias of 4.0 V.