Extended Data Fig. 4: DFT results for Sb–MoS2, Bi–MoS2 with sulfur vacancy and Bi–WS2.
From: Ultralow contact resistance between semimetal and monolayer semiconductors
a, PLDOS of MoS2 before (upper) and after (lower) contact with Sb. The valence band (VB) is shaded in light blue and conduction band (CB) in light red. The Fermi level (EF) is shifted from the valence band maximum inside the gap (before Bi contact) into the conduction band (after Bi contact). b, c, LDOS of MoS2 with a sulfur vacancy (b) and WS2 (c) when in contact with Bi. The Fermi level is pinned at the sulfur vacancy defect state inside the bandgap. This implies that a high-quality TMD crystal with a low defect density is critical to form ohmic contact to Bi. The result of LDOS of WS2 in contact with Bi, predicting that ohmic contact can also be formed at the Bi–WS2 interface owing to gap-state saturation.
