Symmetry Engineering in a 2D Transition Metal Enables Reconfigurable P- and N-Type FETs.

Two-dimensional (2D) transition metals enable the elimination of metal-induced gap states and Fermi-level pinning in field-effect transistors (FETs), offering an advantage over conventional metal contacts. However, transition metal substrates typically exhibit nonoriented behaviors, leading to the inability to achieve monolingual responses with P- or N-type semiconductors. Here we devise symmetry engineering in an oxidized architectural MXene, termed OXene, which implements the exploiting and coupling of additional out-of-plane electron conduction and built-in polar structures. OXene combines oriented inhibitory and excitatory characteristics to achieve reconfigurable FET substrates, leveraging the modulation carrier dynamics at the metal-semiconductor interface. By coupling OXene with MXene, we achieve complementary semiconductor responses that introduce an additional dimension of programmability in logic configurations.