| 摘要 |
PROBLEM TO BE SOLVED: To provide a high precision mode field region by forming a mesa construction comprising a stripe portion and a taper portion for an upper clad layer above an active layer of a quantum well and by thermally treating a ZnO/SiO2 layer vapor which is deposited on the active layer of the quantum well around the upper clad layer. SOLUTION: A lower clad layer 12, and an active layer 13, containing a quantum well and a light confinement layer, are sequentially grown on a substrate 11 and, on this active layer 13, a ZnO layer 14 and SiO2 layer 15 are formed by sputtering, and this ZnO/SiO2 layer is turned into a mask pattern 16 by patterning. Next, a mesa comprising a taper portion on a taper region 22 and a stripe portion on a stripe region 21 with the shape restricted by the mask pattern 16 is formed. During a selective growth of mesa comprising the upper clad layer 17 and the cap layer 18, the Zn which consists of ZnO/SiO2 layer is scattered below the mask, depending on the growing temperature and the active layer 13 is disordered, thereby forming a Zn-diffused region 19. |
