Different configurations of microwave monolithic amplifiers are shown. The first one works between 0. 5 to 7 GHz with a gain of 10 db. The second one is a distributed amplifier having a gain of 6 db and a noise factor of 6 db between 0. 5 and 7 GHz. A third circuit having an arborescent structure which is best suited to a power amplifier is presented. Its gain is 14 db and the output power is 400 mW between 5. 9 and 6. 4 GHz. All these circuits include 1 mu m gate length, silicon nitride overlay capacitors, active layer or metallic resistances and air bridges.