English
In this study, the potential of 2D semimetallic PtSe2 as a source/drain (S/D) contact for 2D material field-effect transistors (FETs) is explored through theoretical and experimental studies. According to density functional theory (DFT) calculations, the semimetallic PtSe2 can inject electrons and holes into MoS2 and WSe2, respectively, suggesting that PtSe2 contacts can be used in n- and p-metal oxide semiconductor FETs (n-/p-MOSFETs). In fact, the contact resistance of experimentally fabricated thin-scale MoS2 n-MOSFETs and WSe2 p-MOSFETs with semi-metallic PtSe2 contacts was significantly reduced compared to conventional Ti/Au contacts. To demonstrate its suitability for large-area electronic devices, MoS2 n-MOSFETs and semi-metallic PtSe2 contacts were fabricated using chemical vapor deposition-grown MoS2 and PtSe2 films. These devices exhibit excellent performance specifications, including high on-current (≈10−7 A/µm) and large on/off ratio (>107). Furthermore, vertically stacked n-MOS inverters were successfully demonstrated using these high-performance MoS2 n-MOSFETs, demonstrating that 3D integration of 2D material FETs is possible using semi-metallic PtSe2 contacts.
