| 摘要 |
<p>PURPOSE:To obtain a phototransistor, which is operated at high speed even to weak incident beams and enables optical bistable operation, by forming a second conductivity type base layer onto a multiple quantum well layer shaped onto a first conductivity type collector layer and a first conductivity type emitter layer onto the base layer. CONSTITUTION:A collector layer 2, an I-AlGaAs layer 3, an I-MQW layer 4, an I-AlGaAs layer 5, a base layer 6 and an emitter layer 7 are crystal-grown on an N-GaAs substrate 1. An emitter electrode 8 and a collector electrode 9 are formed, and a hole is shaped to the N-GaAs substrate through etching to form a window 15 for outgoing beams. A well layer consists of AlxwGa1-xwAs and has thickness <= 300Angstrom and a barrier layer is composed of AlxbrGa1-xbrAs and has thickness >20Angstrom in said I-MQW layer 4. The base layer 6 is constituted of P-AlxbGa1-xbAs (where xb>xw) and has thickness < diffusion length of electrons, and the emitter layer 7 is organized of N-AlxeGa1-xeAs and has thickness of 0.2mum.</p> |
