A power MOSFET device includes a semiconductor body having a first main surface. The semiconductor body includes an active area facing the first main surface. The power MOSFET device includes an isolated-gate structure, which extends over the active area and includes a gate-oxide layer, which is made of insulating material and extends over the first main surface, and a gate region buried in the gate-oxide layer so as to be electrically insulated from the semiconductor body. The gate region includes a gate layer of polysilicon and at least one first silicide electrical-modulation region and one second silicide electrical-modulation region, which extend in the gate layer so as to face a top surface of the gate layer and to be arranged alongside one another and spaced apart from one another in a first plane.