| 摘要 |
PURPOSE:To increase gate withstand voltage by forming a P-N junction gate in a field effect transistor, which is operated at high speed by utilizing a secondary electron gas and has the same conduction type hetero-junction. CONSTITUTION:A non-doped GaAs layer 1, an N type AlGaAs layer 2, an N type AlGaAs layer 3, the ratio of Al therein is decreased gradually, an N type GaAs layer 4 and lastly a P type AlGaAs layer 5 are grown on an insulating substrate in order from the lowermost section. A mesa is formed for an isolation. A gate electrode section is patterned by using a resist 6, and gate gold layers 7 and 8 are applied in vacuum, thus forming the gate electrode 8. Only the P type AlGaAs layer 5 is etched selectively. A P-N junction gate shorter than the gate length of the gate electrode 8 can be obtained extremely easily through a side etching up to the lower section of the gate electrode 8 at that time. |
