An integrated electronic device includes a semiconductive film above a buried insulating layer that is situated above a supporting substrate. An active zone is delimited within the semiconductive film. A MOS transistor supported within the active zone includes a gate region situated above the active zone. The gate region includes a rectilinear part situated between source and drain regions. The gate region further includes a forked part extending from the rectilinear part. A raised semiconductive region situated above the active zone is positioned at least partly between portions of the forked part. A substrate contact for the transistor is electrically coupled to the raised semiconductive region.