COMPOUND SEMICONDUCTOR DEVICE

PURPOSE:To design an LSI and VLSI composed of a plurality of elements, and to contribute to the design of an analog element particularly by inhibiting mutual intervention between the two elements. CONSTITUTION:The drain 2, source 3 and gate 4 of a first MESFET are formed onto a GaAs substrate 1, and the source 5, drain 6 and gate 7 of a second MESFET are shaped. A control electrode 8 to which negative potential must be applied to the source of the first MESFET is shaped between the two elements through Be ion implantation, etc. A second novel doping layer and a P diffusion layer 9 are formed by using the same doping technique. The relative positional relationship is positioned between the first element, which must prevent deterioration, and the control electrode 8. A proper value exists between the P diffusion layer (a channel stopper) and the source 3 as the first element at that time and takes 2.0mum or more in normal cases, but it depends upon the characteristics of the substrate and is not necessarily kept constant.