| 摘要 |
<p>PURPOSE:To form one layer in buried layers in a photodetector corresponding to the buried layer limiting a light-emitting section in upper and lower electrodes having different conductivity, to increase a light-receiving area and to reduce dark currents resulting from the buried layers by giving energy smaller than the band gap energy of a light-emitting layer to one layer in the buried layers in the photodetector. CONSTITUTION:A laser section 53 and a light-receiving section 54 isolated by an isola tion trench 52 are formed onto an N-type InP substrate 44, and P-type InGaAsP layers 41, 41' are shaped to each of the sections 53 and 54. P-type InP clad layers 42, 42' are formed, and an InGaAsP light-emitting layer 43 is shaped to the section 53 and an InGaAsP layer 43 to the light-receiving section 54. P-type InP layers 49, 49', N-type InP layers 48, 48' and a P-type InGaAsP gap layer 47 and a P-type InGaAsP light- receiving layer 47 are formed to each of the sections 53, 54. A laser electrode+45 and a laser electrode-46 are shaped to the light-emitting layer 43 emitting laser beams 50, and a light-receiving section electrode+51 and a light-receiving section electrode-45 are formed to the light-receiving section 54. The band gap energy of one layer in the light-receiving section is made smaller than that of the light-emitting layer 43.</p> |
