| 摘要 |
PURPOSE:To obtain a field effect transistor used as a high efficiency 2-terminal oscillating or amplifying element by setting the distribution to an abnormal value so that the region wherein an active layer is disposed in a high resistance region higher than the lower part of a gate electrode between a source electrode and a gate electrode. CONSTITUTION:An n type low density buffer layer 12 and an n type high density active layer 13 are formed on a semi-insulating GaAs substrate 11, and the layer 13 is formed to be narrower in width than the active layer 132 lower than the gate electrode in width of the part 131 between the source and the gate electrodes of the layer 13. Thus, the active layer partly becomes high resistance, thereby forming an FET 10. This structure can be obtained merely by varying the planar shape of the active layer of the conventional FET. When a source electrode 14 and a gate electrode 16 are covered on the semi-insulating semiconductor substrate 11 in a common connection such as by a metal film 17, the terminal to be connected with the external circuit of the FET 10 become two of gate and drain electrodes 16, 15, and one can be reduced as compared with the conventional FET. |
