Fig. 4: The properties of transferred graphene.
a Typical transfer curves of as-transferred graphene after encapsulation by hBN and one-dimensional contacting at 300 K (navy blue) and at 4 K (red). Inset: Illustration of the measured Hall bar devices of encapsulated graphene. b The statistics of obtained carrier mobilities of the encapsulated graphene at 300 K (navy blue) and at 4 K (red). c Rxx (navy blue) and Rxy (red) as a function of magnetic field (B) at a fixed gate voltage (−50 V). Inset: Rxx as a function of B scanning from −0.2 to −2 T. Rxx is the longitude resistance, which can be obtained according to the equation: Rxx = Vxx/Ids, and Rxy is the Hall resistance which can be obtained by Rxy = Vxy/Ids. d Raman spectra of as-transferred graphene encapsulated by hBN. e Sheet resistance statistics of graphene on PET substrates doped by PEDOT:PSS. Inset: Corresponding A4-sized sheet resistance mapping of the doped graphene. f Ultraviolet-visible (UV-Vis) transmittance spectra of graphene films (black) and doped graphene films by PEDOT:PSS on PET substrates (red). Note that graphene in (a, c) was transferred by cedrol (10 wt%)/PMMA; devices No. 1, 2 were transferred by borneol (10 wt%)/PMMA; devices No. 3, 4, and 5 were transferred by alpha-terpineol (10 wt%)/PMMA; devices No. 6, 7, 8 were transferred by linalool (10 wt%)/PMMA and devices No.9, 10 were transferred by cedrol (10 wt%)/PMMA. Their corresponding Raman spectra were shown in (d). Note that the mass fraction of borneol in n-heptane should not be higher than 10% to avoid precipitating from the PMMA solution.
