A semiconductor device includes an isolation pattern disposed on a substrate, the isolation pattern defining an active part, a gate pattern crossing the active part on the substrate, the gate pattern including a dielectric pattern and a first conductive pattern, and the dielectric pattern being between the active part and the first conductive pattern, a pair of doping regions in the active part adjacent to side walls of the gate pattern, the gate pattern being between the pair of doping regions, and a diffusion barrier element injection region disposed in an upper region of the active part.