| 摘要 |
PURPOSE:To emit light by injecting currents to an emitter-base junction, to suck out carriers stored in an active layer forcibly by applying a reverse bias to a base-collector junction and to increase a modulation rate by forming the active layer as a light-emitting layer between an emitter layer and a base layer. CONSTITUTION:Holes are injected to an active layer 14 from an emitter layer 15 and electrons from a buried layer 17 (one part is injected through a base layer 13), and injected holes and electrons recombine in the active layer 14 and emit light. Carriers injected to the active layer 14 are sucked out in such a manner that a depletion layer in the base layer 13 is extended until it reaches to the emitter layer 15 by reverse-biassing a junction between a collector layer 12 and the base layer 13 and sections among the emitter layer 15, the active layer 14, the base layer 13 and the collector layer 12 are brought to the state of a punch- through. Accordingly, the limit of the speed of operation by the recombination rate of carriers in the active layer which has been generated by a conventional BH laser is eliminated, and modulation at high speed is enabled. |
