Homogeneous MoTe2 CMOS inverters enabled by work function-engineered van der Waals contacts

We demonstrate that homogeneous MoTe2 complementary metal–oxide–semiconductor (CMOS) inverters can be constructed through a simple work function engineering strategy using van der Waals contacts. Polarity control of MoTe2 transistors is achieved by employing high-work function degenerated semiconductor SnSe2 and low-work function semimetal Bi as source/drain electrodes for p-type and n-type operation, respectively. Both types of transistors operate in enhance-mode and exhibit on/off current ratios exceeding 106. The resulting homogeneous MoTe2 CMOS inverter, incorporating an h-BN flake as the gate dielectric, achieves a high voltage gain of 78 at a supply voltage of 4 V. These results highlight the potential of this simplified device architecture for realizing high-performance homogeneous MoTe2 CMOS logic circuits.