Transistor gating by polar molecular monolayers

摘要

In order to determine the role of polar monolayers in molecular-gated transistors we combine Kelvin probe force microscopy and current-voltage measurements of hybrid silicon-on-insulator metal-oxide-semiconductor field-effect transistors. Layers having alternating net-dipole direction were self-assembled on the top dielectric layer of the transistors. Nonzero field-effect was observed only with an amine-terminated monolayer and is attributed to the protonation of the amine groups. No correlation between the field-effect and the net-dipole of the molecular layers was found; this effect is discussed and explained.