A fully ion implanted GaAs FET technology has been developed that allows the fabrication of a state-of-the-art power transistor for general purpose applications. The fabrication technology employs an LPE buffer layer on a semi-insulating substrate with an implanted channel layer and implanted n+sub-drain and sub-source regions. Success was achieved through the development of a self-aligned fabrication process. The device itself is a 1.5 mm wide by 1.5 µm long gate FET. Output power performance of more than 1 watt with 5 db gain and a power added efficiency of 34% has been achieved at 6 GHz. The high source to drain breakdown voltage attributable to the implanted n+structures enable the device to run at higher voltage and higher efficiency. The device is designed for use in broadband amplifiers with bandwidths greater than an octave.