Temperature dependence of carrier mobility in chemical vapor deposited graphene on high-pressure, high-temperature hexagonal boron nitride

Abstract

The temperature dependence of the electrical properties of graphene grown by chemical vapor deposition (CVD) on high-pressure high-temperature (HPHT) hexagonal boron nitride (h-BN) was evaluated to understand the carrier scattering mechanism of CVD graphene. The effect of the thickness of HPTH h-BN on the carrier mobilities was also discussed. Carrier mobility was found to depend on HPHT h-BN thickness for the temperature range of 80–473 K. Coulomb scattering due to charged impurities present between HPHT h-BN and SiO2 was suppressed by increasing the HPHT h-BN thickness. The results did not confirm any temperature dependence of the carrier mobility of CVD graphene on HPHT h-BN (thickness = 6 and 11 nm). For CVD graphene on HPHT h-BN (thickness = 19 and 23 nm), the carrier mobility was limited by the phonon scattering of graphene for low temperatures and by surface phonon scattering of h-BN for high temperatures. Intrinsic graphene electrical properties were obtained using thicker HPHT h-BN.