An integrated circuit transistor is formed on a substrate. A trench in the substrate is at least partially filed with a metal material to form a source (or drain) contact buried in the substrate. The substrate further includes a source (or drain) region in the substrate which is in electrical connection with the source (or drain) contact. The substrate further includes a channel region adjacent to the source (or drain) region. A gate dielectric is provided on top of the channel region and a gate electrode is provided on top of the gate dielectric. The substrate may be of the silicon on insulator (SOI) or bulk type. The buried source (or drain) contact makes electrical connection to a side of the source (or drain) region using a junction provided at a same level of the substrate as the source (or drain) and channel regions.