| 摘要 |
PURPOSE:To make high speed response feasible by a method wherein a buffer layer meeting specific requirements is laid between a light absorbing layer and an avalanche layer. CONSTITUTION:A buffer layer 4 with the difference DELTAEc of conductive band disconnection to a semiconductor comprizing a light absorbing layer larger than the difference DELTAEv of valence electron band disconnection is laid between a light absorbing layer 2 (InGaAs) and an avalanche doubling layer 3 (InP). In case of an actuation as shown in Fig. (b), electrons will be accumulated on the avalanche layer side interface due to the conductive band disconnection between the avalanche layer 3 and the buffer layer 4 to impress the interface between said two layers 3 and 4 with high electric field. The band of the interface between the avalanche layer 3 and the buffer layer 4 is bent so that the tunnel transmission of the hole carriers accumulated in the buffer layer 4 may be made easier to relieve the accumulating effect of the hole carriers. Therefore the conventional deterioration of high speed response may be improved. |
