The field effect transistor comprises a substrate successively comprising an electrically conducting support substrate, an electrically insulating layer and a semiconductor material layer. The counter-electrode is formed in a first portion of the support substrate facing the semi-conductor material layer. The insulating pattern surrounds the semi-conductor material layer to delineate a first active area and it penetrates partially into the support layer to delineate the first portion. An electrically conducting contact passes through the insulating pattern from a first lateral surface in contact with the counter-electrode through to a second surface. The contact is electrically connected to the counter-electrode.