Abstract: A semiconductor device having a semiconductor body includes a field effect transistor and an active transistor region with two electrode zones, one of which surrounds the other, and an island zone which is situated therebetween. These zones enclose channel regions over which there are provided gate electrodes, the first one of which surrounds the second. The gate electrodes are connected to bond pads present outside the active transistor region. The first gate electrode is interrupted at the area of the connection from the second gate electrode to a bond pad, both its ends being connected to another bond pad. Even at very high frequencies, the transistor exhibits a high gain, a high transconductance and a low input attenuation.

Abstract: Method of manufacturing a semiconductor device, in particular a capacitance diode, a zener diode or an avalanche diode, by using only one masking step. According to the invention, a first masking layer, for example a silicon oxide layer, is provided on a substrate of one conductivity type the etching rate of which at the surface is increased, for example, by an argon bombardment. A second masking layer is provided on the first masking layer and a window is etched therein. Via said window a first zone preferably of the same conductivity type as the substrate is implanted while using the second masking layer as a mask. The first masking layer is etched via the same window so that a bevelled edge is formed. By ion implantation via the window and a part of the bevelled edge, a second zone is formed which forms a p-n junction preferably with the first zone and the substrate.