Top-Gate Graphene-on-UNCD Transistors with Enhanced Performance

摘要

We fabricated a number of top-gate graphene field-effect transistors on the ultrananocrystalline diamond (UNCD) - Si composite substrates. Raman spectroscopy, scanning electron microscopy and atomic force microscopy were used to verify the quality of UNCD and graphene device channels. The thermal measurements were carried out with the "hot disk" and "laser flash" methods. It was found that graphene on UNCD devices have increased breakdown current density by ～50% compared to the reference devices fabricated on Si/SiO_2. The relatively smooth surface of UNCD, as compared to other synthetic diamond films, allowed us to fabricate top gate graphene devices with the drift mobility of up to ～ 2587 cm~2V~(-1)s~(-1).