Phosphorus oxide gate dielectric for black phosphorus field effect transistors (original) (raw)

The environmental stability of the layered semiconductor black phosphorus (bP) remains a challenge. Passivation of the bP surface with phosphorus oxide, PO x , grown by a reactive ion etch with oxygen plasma is known to improve photoluminescence efficiency of exfoliated bP flakes. We apply phosphorus oxide passivation in the fabrication of bP field effect transistors using a gate stack consisting of a PO x layer grown by reactive ion etching followed by atomic layer deposition of Al 2 O 3. We observe room temperature top-gate mobilities of 115 cm 2 V À1 s À1 in ambient conditions, which we attribute to the low defect density of the bP/PO x interface. V