Fig. 2: Mechanical and electrical properties of GGFF and h-BN/GGFF.
a Schematics for the conformal encapsulation by in-situ CVD-grown h-BN (left), and the whole-package encapsulation by ex-situ h-BN and polyimide (PI) film (right). b Photographs of h-BN/GGFF (25 × 120 mm2) under a series of mechanical deformations, showing the high flexibility. c Bending length of GGFF, h-BN/GGFF, PI/GGFF, and PI/h-BN/GGFF. GGFFs used have graphene thickness of ~1.0 nm, and h-BN/GGFF used have graphene and h-BN thickness of ~1.0 nm and ~50.4 nm, respectively. The error bars represent the standard deviations (n = 5). d Sheet resistance of GGFF at varying thickness of graphene. Sheet resistance mappings of GGFF (e) and h-BN/GGFF (f). In e, f, the size of GGFF and h-BN/GGFF is 5 × 5 cm2. GGFF has graphene thickness of ~1.0 nm, and h-BN/GGFF has graphene and h-BN thickness of ~1.0 nm and ~29.5 nm, respectively. Sheet resistance values were measured using a four-point probe with 0.5 cm step size in both x- and y-directions. g Schematics of the test devices based on GGF and h-BN/GGF. h Current flowing through GGF and h-BN/GGF test devices in g under the input voltage of 10 V. i Electrical transport measurements (current-voltage (I-V) curves) of GGF and h-BN/GGF test devices in g for voltages ranging from 0 V to 200 V. In g–i, the length of GGF and h-BN/GGF is ~0.5 cm. GGF has graphene thickness of ~1.0 nm, and h-BN/GGF has graphene and h-BN thickness of ~1.0 nm and ~50.4 nm, respectively.
