Cryogenic Operation of Junctionless Ambipolar MOSFET Fabricated on Intrinsic Si Substrate

Abstract

It has been reported that the work function of a metal can be modulated by the electric dipole layer formed at the interface when graphene is contacted to the metal. This suggests that one type of metal can be used as a gate electrode for both n- and p-channel metal oxide semiconductor field effect transistor (MOSFET) with a graphene layer accompanied properly. We fabricate Schottky Barrier MOSFET structures which can work in cryogenic environment by using an Al gate metal and a graphene interlayer inserted selectively underneath the gate metal, together with silicide source/drain contacts. The operational characteristics of fabricated device is investigated by measuring its transfer curves in wide temperature range, 5~300K. The unique properties expected for the designed structure, ambipolar transport and threshold voltage shift, are observed clearly at low temperatures. These properties ensure the possibility of constructing the cryogenic complementary MOS (CMOS) circuitry composed of n- and p-channel MOSFETs just by using the single metallization process.

NRF- 2023R1A2C1006519