| 摘要 |
PURPOSE:To increase a gate-to-drain breakdown strength, to reduce source resistance and to improve low noise characteristics by controlling a position accurately whereon a gate electrode is formed by a hole which is formed by etching in a third structure layer and by forming a gate electrode near a source region and apart from a drain region. CONSTITUTION:A resist pattern having an opening apart from a side to form a drain and near a side to form a source is formed on an SiN layer 18 corresponding to an etched range of an SiN layer 14. An SiON layer 17 and the SiN layer 18 are etched using it as a mask to expose an n<+>GaAs layer 13. Then, the resist pattern is removed and a hole 21 is formed. A resist pattern 19 having an opening 22 which is larger than the hole 21 is formed to make the hole 21 position inside the opening 22. An SiON layer 17 is side-etched with a specified etchant through the hole 21, the n<+>GaAs layer 13 exposed from the hole is etched to expose an n<+>AlGaAs layer 12, a vertical gate metal 26 such as Al, W is deposited, the resist pattern 19 is removed an the unnecessary gate metal 26 on the resist pattern 19 is lifted off.
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