Figure 1
The control of domain shape and size of h-BN flakes.
(a) to (d) are the OM images of h-BN domain grown on Cu foil with Ar gas (30 sccm) pre-annealing time varying from 1 hour, 2 hours, 3 hours and 4 hours and then grow under H2 gas (10 sccm) and show different kinds of h-BN domain shapes. (e) to (h) are the OM images of triangle-shape h-BN domain grown under different H2 gas flow, varying from 5 sccm, 20 sccm, 30 sccm and 40 sccm, after 1 hour of Ar gas pre-annealing. (i) is the diagram to show the change of the percentage of different shapes of h-BN varying with Ar (30 sccm) gas pre-annealing time; (j) is the diagram to show the change of domain size of triangle-shape h-BN varying with hydrogen gas flow; (k) is the diagram to show the percentage of parallel domains varying with flake density; (l) is the diagram to show the portion of parallel direction of different h-BN domain shapes. The counted h-BN domains show in diagram of (i,k,l) are within the area of 60 μm × 50 μm; All the scale bars in (a–g) are 10 μm and in (h) is 20 μm.
