| 摘要 |
PURPOSE:To obtain the thyristor of a low on-state voltage by sufficiently thickening a thickness of a P-type layer of the lowest impurity concentration compared with other P-type layers and N-type layers in the thyristor and using GaAs as a principal material so as to increase a dependable temperature over 150 deg.C. CONSTITUTION:As a thermal excitation current of GaAs is exceedingly small compared with that of Si and also a value of off-state current is low, if it is assumed that the permissible off-state currents are the same, the thyristor of GaAs is capable of operating at higher temperature. However, if GaAs is used as a principal material while keeping a conventional structure, the sufficient on-state characteristics can not be obtained as an on-state voltage is high. When a thickness of a PB layer 3 is large sufficiently compared with other layers and the impurity concentration is made lowest, a reverse voltage is blocked by the junction J3 of an NE layer 4 and the PB layer 3 and an off-state voltage forward direction is blocked by the junction J2 of the PB layer 3 and an NB layer 2. A gate electrode 7 is arranged on the NB layer 2 and a forward voltage which makes an anode 5 positive is applied to a cathode 6. Then a negative bias voltage which makes the gate electrode 7 negative is applied to the anode 5, thereby enabling turn-on. |
