| 摘要 |
<p>PURPOSE:To arrange a photo-transistor to the upper section of a laser diode, and to realize a signal light transmission type optical semiconductor device, in which the position of the input and position of output of a signal are equalized, by using a lattice mismatch graded layer or a P-type substrate. CONSTITUTION:The arrangement of a laser diode and a photo-transistor is exchanged to upper and lower sections, and an electrode functioning as a reflecting mirror in combination is not disposed to a laser diode section. A lattice mismatch graded layer generating extremely large leakage currents is arranged between the P-type mirror section or the laser diode and the N-type collector layer section of the photo-transistor so that breakdown strength characteristics are not generated by a P-N junction generated between the P-type mirror section and the N-type collector layer section at that time. An electrode in the upper section of an emitter layer is formed in a shape having a window, into which signal light is input. Accordingly, a transmission type can be realized as the positions of the input and output of signal light are left as they are equalized.</p> |
