Patent ID: 7193255

Claim:
A semiconductor device comprising: a compound semiconductor substrate; a first field effect and a second field effect transistor, each of the transistors being formed on the substrate and comprising an operating region and a gate electrode, a source electrode and a drain electrode that are connected with the operating region; a common input terminal pad connected with the source or drain electrode of the first transistor and connected with the source or drain electrode of the second transistor; a first output terminal pad connected with the source or drain electrode of the first transistor that is not connected with the common input terminal pad; a second output terminal pad connected with the source or drain electrode of the second transistor that is not connected with the common input terminal pad; a first control terminal pad; a first electric connection connecting the first control terminal pad and the gate electrode of the first transistor; a second control terminal pad; a second electric connection connecting the second control terminal pad and the gate electrode of the second transistor; a conducting region disposed in or on the substrate that is in electric contact with one of the common input terminal pad, the first and second output terminal pads and the first and second control terminal pads, or a wiring connected with one of the common input terminal pad, the first and second output terminal pads and the first and second control terminal pads, or a wiring connected with one of the operating regions; and floating conducting region that is configured not to receive any electric potential, the floating conducting region being disposed between one of the operating regions and the conducting region, between the operating region of the first transistor and the operating region of the second transistor, between one of the first and second electric connections and one of the operating regions, between the first and second electric connections or between the common input terminal pad and one of the first and second electric connections.