A semiconductor device includes a semiconductor substrate having a resistor region, an isolation layer disposed in the resistor region, the isolation layer defining active regions, first conductive layer patterns disposed on the active regions, a second conductive layer pattern covering the first conductive layer patterns and disposed on the isolation layer, the second conductive layer pattern and the first conductive layer patterns constituting a load resistor pattern, an upper insulating layer disposed over the load resistor pattern, and resistor contact plugs disposed over the active regions, the resistor contact plugs penetrating the upper insulating layer to contact the load resistor pattern.