Reply to the ‘Comment on “Electron-interfered field-effect transistors as a sensing platform for detecting a delicate surface chemical reaction”’ by M. Micjan and M. Weis, J. Mater. Chem. C, 2026,14, DOI: 10.1039/D5TC02689J

초록

Michal Micjan and Martin Weis argue that electron-interfered FET (EIFET) cannot detect surface reactions via threshold-voltage shifts (ΔVth) because charge produced at the interference electrode (IE) must manifest primarily as a gate current (IG); they further suggest that the reported Vth dynamics arise from bias-stress and interfacial trapping rather than chemistry at the IE. We rebut these claims on three grounds. First, a capacitive-network analysis shows that the transient displacement current, IG, is quantitatively and operationally negligible, while the quasi-static Vth modulation is the only relevant observable. Charge transiently accumulated at the IE modulates the effective gate bias through capacitive coupling and produces a measurable, reversible Vth(t) signal. Second, the characteristic Vth(t) signature co-varies with an independent surface-science observable—the IE surface energy γs(t)—and survives stringent controls (dielectric substitution, solvent/ionic solutions, and preformed SAMs) that a trap-only hypothesis cannot explain. Third, the magnitude and time scale of ΔVth are quantitatively consistent with small, transient IE charge densities (1011–1012 cm−2), far below monolayer coverages and fully compatible with the proposed mechanism. This journal is © The Royal Society of Chemistry, 2026