| 摘要 |
PURPOSE:To improve the current gain in the region operating with high current, by equalizing the energies on the bottoms of the upper valleys of the semiconductor used for a base and of the semiconductor of a barrier layer or providing a lower energy on the bottom of the upper valley of the semiconductor of the barrier layer. CONSTITUTION:An N-type In0.53Ga0.47As collector layer 5, an undoped InP or Al0.48In0.52As barrier layer 4, an N-type In0.53Ga0.47As base layer 3, an undoped InP or Al0.48In0.52As barrier layer 2 and an N-type In0.53Ga0.47As emitter layer 1 are formed on an InP substrate 6 in that order with their lattices aligned. Emitter, base and collector electrodes 7, 8 and 9 are formed with AuGs/Au. When the device operates with high current with the bias between the emitter and the base increased, electrons whose speed has been decreased as a result of their climbing on an upper valley can reach the collector if they merely pass through the base 3 since there is no barrier in the upper valley. As a result, the current gain can be improved. |
