| 摘要 |
PURPOSE:To operate a GaAs IC at high speed and increase the performance of the IC by forming the whole or at least a section being in contact with a substrate of a gate electrode in a tungsten nitride film and forming the tungsten nitride film through a reactive sputtering method in a mixed gas of nitrogen gas at a specific partial pressure ratio and argon gas. CONSTITUTION:Si<+> ions are implanted to a semi-insulating GaAs crystal substrate 31 while using a SiO2 film 32 as a mask, and an active layer 33 is formed through heat treatment. A WN film 34 is deposited on the whole surface of the substrate through reactive sputtering. The sputtering is executed in a mixed gas of N2, a partial pressure ratio thereof is brought to 0.03-0.2, and Ar. The WN film 34 is patterned through dry etching while using a photo-resist as a mask to form a gate electrode. Si<+> ions are implanted again while employing the gate electrode as a mask to shape ion implantation layers 35, 36. The whole surface of the substrate is coated with a PSG film 37, and source and drain regions 35', 36' are formed through heat treatment. Openings are bored to the PSG film 37, and source and drain electrodes 38, 39 are formed. |
