| 摘要 |
PURPOSE:To facilitate the formation of mixing FETs by forming a plurality of normally ON and OFF FET channels on a semi-insulating substrate, respectively forming source and drain electrodes, then etching and removing part of a gate electrode forming part in the channel of the normally OFF FET and forming a gate electrode at the part. CONSTITUTION:The first insulating film 12a of the prescribed shape is formed on a semi-insulating substrate 11, a resist 13a is covered, and normally ON and OFF MESFET channels 15, 16a are formed by ion implantation on the surface layer of the exposed substrate 11. Then, the resist 13a is removed, annealed in AsH3 gas to activate N type impurity in the channels 15, 16a, and source and drain electrodes 17, 18 are respectively formed at the periphery of the surfaces. Thereafter, the center of the region 16a of the normally OFF is etched and removed, a gate electrode 19a is buried, and a gate electrode 19b is formed on the surface of the region 16. |
