Schottky diode via dielectrophoretic assembly of reduced graphene oxide sheets between dissimilar metal contacts

We demonstrate the fabrication of reduced graphene oxide (RGO) Schottky diodes via dielectrophoretic (DEP) assembly of RGO between two dissimilar metal contacts. Titanium (Ti) was used to make a Schottky contact, while palladium (Pd) was used to make an Ohmic contact. From the current-voltage characteristics, we obtain rectifying behavior with a rectification ratio of up to 600. The ideality factor was high (4.9), possibly due to the presence of a large number of defects in the RGO sheets. The forward biased turn-on voltage was 1V, whereas the reverse biased breakdown voltage was 3.1 V, which improved further upon mild annealing at 200°C and can be attributed to an increase in the work function of RGO due to annealing.