Semiconductor device having diffusion barrier covering source/drain and forming method thereof

PURPOSE: A semiconductor device having a diffusion barrier covering a source/drain and a forming method thereof are provided to simplify the fabrication process by forming a conductive layer pattern for playing a role of a contact as well as a role of the source/drain. CONSTITUTION: A semiconductor device having a diffusion barrier covering a source/drain includes a gate pattern, a recessed region, a channel part, and a diffusion barrier. A top part and a sidewall of the gate pattern are covered by a capping layer pattern. The recessed region(17) is formed on a semiconductor substrate(1) of both sides of the gate pattern. The channel part(C) is formed on an upper part of a sidewall of the recessed region corresponding to a lower part of the gate pattern. The diffusion barrier(19) is formed on a bottom of the recessed region except for the channel part and a part of a sidewall connected to the bottom of the recessed region.