Embodiments of the invention provide a robust mechanism to isolate transceivers that attempt to train on a FEXT channel during the handshake phase and to abort a false activation. The diffusion barrier comprises a self-assembled monolayer on a semiconductor substrate, where one surface of the SAM is disposed in contact with and covalently bonded to the semiconductor substrate, and one surface of the monolayer is disposed in contact with and covalently bonded to a metal layer. In another embodiment, a horizontal insulating layer located below at least one of the source and drain regions and a vertical insulating layer located below at least one side surface of the gate are realized. Antenna units in the antenna apparatus may be oriented at different angular positions along an array.