| 摘要 |
PURPOSE:To obtain the excellent FET characteristics for the titled semiconductor device by a method wherein the surface of a substrate is formed by providing three layers thereon, an aperture part is provided by selectively removing the surface layer in such a manner that it is made wider as going deeper to the underlayer, and a gate metal layer is formed on the region ranging from the aperture part on the surface to the substrate located directly below the aperture, thereby enabling to reduce the effect of the depletion layer on the surface. CONSTITUTION:The N type working layer 21 is formed on a semiinsulative GaAs substrate, an Al layer 22 is formed thereon, and an SiO2 layer 23 is formed on said layer 22. Then, photoresist layer 24 is applied, and an aperture 25 of 1.0mum in length for formation of electrode pattern is provided. Subsequently, an aperture 27 which is wider than said aperture 26 is provided by performing a side-etching on an Al layer 22. Then, a gate electrode 29 is formed as a gate metal 28 by vapor-depositing an Al layer 28 of 0.3mum in thickness. Then, the gate electrode 28 located on a photoresist film 24 is removed by dissolving the photoresist film 24 using acetone. Then SiO is vapor-deposited on the gate electrode 29 as the first coating film 30, and subsequently SiO2 is vapor-deposited thereon as the second coating film 31. |
