A semiconductor device includes a semiconductor substrate having a principal plane on which gate, source, and drain electrodes are located. A film made of a polymer with a low dielectric constant is over the gate and drain electrodes to insulate the gate and drain electrodes from the source electrodes. A chip surface electrode located over the low-dielectric-constant polymer film and the source electrode, and connected to ground potential. The source electrode is provided with the ground potential through the chip surface electrode.
