| 摘要 |
PURPOSE:To implement low noises and high gain in an FET, by making the thickness of a channel provided in the active layer in the FET thinner along the path from a source electrode to a drain electrode as the drain electrode is approached. CONSTITUTION:A channel 10 is formed in an asymmetrical shape so that the thickness of an active layer 3 becomes thinner toward the side of a drain elec trode 5 from the side of a source electrode 4 as the drain electrode 5 is approached. The minimum thickness is about 1,200Angstrom . In this structure, the source resistance is made lower than the conventional value by about 50%. The gate withstanding voltage can be increased by about twice. The impurity concentration of the active layer 3 is 2-4 X 10<17> cm<-3>, and the gate length is 0.5-1mum. |
