Abstract: A method for manufacturing a power transistor. The method includes: applying a first epitaxial layer including a first doping concentration to a front side of a semiconductor substrate, producing an expansion layer, which is situated inside the first epitaxial layer, producing various implanted areas starting from the front side of the semiconductor substrate, producing a trench structure starting from the front side of the semiconductor substrate, producing first isolation areas in the surroundings of the trench structure, producing transistor heads, and applying metal layers.