A semiconductor transistor device includes a substrate having an active area and a trench isolation region surrounding the active area, a gate oxide layer, a gate, a spacer on a sidewall of the gate, a doping region on one side of the gate, an insulating cap layer covering the gate, the spacer and the doping region, and a redistributed contact layer (RCL) on the insulating cap layer. The RCL extends from the active area to the trench isolation region. A contact plug is disposed above the trench isolation region and is electrically connected to the gate or the doping region through the RCL.