| 摘要 |
PURPOSE:To reduce the deterioration of noise figure bypassing the current in a superhigh frequency band by a method wherein a high concentration layer is formed on a semiconductor substrate in parallel with an active layer, and an electrostatic capacitor is added in parallel to a parasitic resistor. CONSTITUTION:The high concentration layer 8' to give electrostatic capacitance between the parasitic resistor existent between a source 2 and a gate 3 and a high concentration layer 6' and the high concentration layer 9' to give electrostatic capacitance between the parasitic resistor existent between the gat 3 and a drain 4 and a high concentration layer 7' are formed. Thereby, the current, when it is in the superhigh frequency band, comes to flow through the electrostatic capacitor between the parasitic resistor existent between the source 4 and the gate 3 and the high concentration layer 8' and through the electrostatic capacitor between the parasitic resistor existent between the gate 3 and the drain 4 and the high concentration layer 9', and the impedance by the electrostatic capacitance decreases, therefore the deterioration of noise figure due to the parasitic resistance can be reduced. |
