HfSe2(1-X)Te2X alloy channel transistor with semimetal HfTe2 contact electrodes

We have demonstrated series ternary HfSe2(1-x)Te2x single crystalline alloys can be synthesized by a general chemical vapor transport approach. These alloys were verified to exhibit composition-dependent bandgap tunability (from 1.1 to 0 eV) by growth process control. Such characteristic offers a feasible way to construct HfSe2(1-x)Te2x alloy channel transistors using Dirac semimetal HfTe2 as contact electrodes, which shows negligible Schottky barrier height. Notably, the HfSe1.8Te0.2 channel transistor with a channel length of 9.48 μm on a 14 nm h-BN dielectric achieves a balance performance with current Ion/Ioff ratio of 9.5 × 104 and an Ion of 0.828 μA/μm. The current investigation of alloy engineering offers a feasible way of developing high-performance HfSe2-based beyond-silicon electronics.