| 摘要 |
PURPOSE:To enable the FET of high withstand voltage and advantageous circuit matching to be easily obtained, by selecting the quantity of an offset and the thickness of an active layer. CONSTITUTION:In a transistor consisting of a source electrode, a gate electrode provided on the active layer dug in, and a drain electrode, when the active layer thickness is ta and the distance between the drain electrode side end of the gate electrode and its active layer dig-in bottom end on the drain electrode side is LGD, the value of X in ta:LGD=1:X is 9 or more. For example, an active layer 12 having a carrier concentration of -2.5X10<17>cm<-3> and a thickness of -0.5mum vapor-epitaxially grown over a semi-insulation GaAs substrate 11 is dug in by varying the thickness from 510Angstrom to 1,600Angstrom in the wafer. A gate electrode 13 of 0.75mm width and 0.5mum length is formed by offsetting 0.3mum and 0.6mum from the center of the dig-in region or the center to the source electrode side; then, each ohmic electrode of a source electrode 14 and a drain electrode 15 is provided. Thereby, the high-output GaAsMESFET of dig-in structure and offset gate can be obtained. |
