Non-Alloyed Ohmic Contacts on GaAs Using Metal-Interlayer-Semiconductor Structure With SF₆ Plasma Treatment

摘要

We demonstrate the effect of SF plasma passivation with a ZnO interlayer in a metal-interlayer-semiconductor (MIS) structure to reduce source/drain (S/D) contact resistance. The interface trap states and the metal-induced gap states causing the Fermi-level pinning problem are effectively alleviated by passivating the GaAs surface with SF plasma treatment and inserting a thin ZnO interlayer, respectively. Specific contact resistivity exhibits reduction when the GaAs surface is treated with SF plasma, followed by ZnO interlayer deposition, compared with the Ti-GaAs ( cm) S/D contact. This result proposes the promising non-alloyed S/D ohmic contact for III–V semiconductor-based transistors.