A semiconductor device including a doped substrate of a first doping polarity and a doped semiconductor material of a second doping polarity. The semiconductor material is on, or in, the substrate, and the second doping polarity is opposite the first doping polarity such that the semiconductor material and the substrate form a diode. The semiconductor device further includes an inductor on or above the semiconductor material, and a pattern in the semiconductor material for reducing eddy currents. The pattern includes a doped semiconductor material of the first doping polarity and a least one trench within the doped semiconductor material of the first doping polarity, wherein, at least at a depth at which the trench is closest to the inductor, the doped semiconductor material of the first doping polarity fully surrounds the trench so that, at least at the depth, the trench does not touch the doped semiconductor material of the second doping polarity.