A fabrication process of GaAs power MESFET is developed, and the characteristics of the fabricated devices are studied.
The epitaxial wafer with a buffer layer and a n-type active layer, which has been grown on semi-insulating substrate sequentially by L.P.E. in our laboratory, is used in this work.
The measured carrier concentration and thickness of the active layer are $0.8\times10^{17}cm^{-3}$ and 1um, respectively.
For the improvement of the current capability, a MESFET with an interdigitated gate structure and $SiO_2$ isolation layer is fabricated.
In order to reduce the series resistance, gold electroplating method is employed.
Total gate width of the fabricated MESFET is 1mm, and its DC characteristics show that the current is modulated to some degree.
Further work is needed to obtain the good performance of MESFET.
