| 摘要 |
PURPOSE:To reduce or eliminate the influence of crystal defect on an element structure by a method wherein an InGaAsP/InP buried hetero type laser is provided with a buried layer of a structure wherein an InGaAsP four-element layer is sandwiched by InP crystals. CONSTITUTION:The first crystal part 1' is composed of an InGaAsP active layer 11 on a substrate 3, a P type InGaAsP surface layer 13, and an InP 12; a buried crystal part 2' of a P type InP 21, an N type InP 22, an N type InGaAsP 24, a P type InP 25, and a P type InGaAsP layer 23 in this order from the substrate InP 3. Since the Peierls force of InGaAsP is larger than that of InP, the advancement of dislocation introduced in the wafer process is inhibited by the presence of the four-element layer 24, and accordingly the reactive current flowing through the buried layer can be reduced. |
