| 摘要 |
PURPOSE:To reduce a thermal resistance by forming a gate electrode and a drain electrode on the upper surface and a source electrode on the lower surface of a wafer, providing a striped groove and connecting an active layer with a substrate by a metal layer. CONSTITUTION:A high purity epitaxial growth GaAs layer 32 and an N-type epitaxial growth GaAs layer 33 are formed on a high ability N-type GaAs substrate 31. A striped groove 35 which arrives through the layer 33 at the layer 32 is formed. A metal layer 36' which exhibits ohmic characteristic and electrically connects the layer 33 with the substrate 31 is provided in the groove 15. A gate electrode 34 and a drain electrode 36 are provided on the layer 33, and a source electrode 37 is provided on the back surface of the wafer. A drain current passes from the electrode 36 through the layer 33, the layer 36' and the substrate 31 to the electrode 37 as designated by an arrow. With this construction, the substrate 31 can be reduced in thickness, the electrode 37 is plated with Au to improve the heat sink property, and a thermal resistance is improved. |
