MANUFACTURING METHOD OF FET

摘要

forming AlxGa1-xAs layer (24a) lattice-matched with a GaAs substrate (20); forming an n channel layer (22) in the substrate (20); forming an Al cap metal (25); etching the layer (24a) with the cap metal mask to form a photoresist pattern as an impurity implantation region pattern; forming an AlGaAs dummy gate (24) by using a mesa-etching; removing the pattern and the cap metal to form and aneal an oxide film thereon to activate the layers (24a,24); forming an opening part into the oxide film to form 1st and 2nd electrode (28) ohmic-contacted with the gate (24); removing the dummy gate (24) to form a mesa hole; and forming a gate electrode (32) into the hole thereby forming a dummy gate with fine line width to reduce the effective gate length.